Accessing Data with Flex

Accessing Data with Flex
Accessing Data with
ADOBE® FLEX® 4.6
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Contents
Chapter 1: Accessing data services overview
Data access in Flex compared to other technologies
Using Flash Builder to access data services
Data access components
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Chapter 2: Building data-centric applications with Flash Builder
Creating a Flex project to access data services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Connecting to data services
........................................................................................... 8
Installing Zend Framework
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Using a single server instance
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Building the client application
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Configuring data types for data service operations
Testing service operations
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
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Managing the access of data from the server
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Flash Builder code generation for client applications
Deploying applications that access data services
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
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Chapter 3: Implementing services for data-centric applications
Action Message Format (AMF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Client-side and server-side typing
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Implementing ColdFusion services
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Implementing PHP services
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Debugging remote services
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Example implementing services from multiple sources
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Chapter 4: Accessing server-side data
Using HTTPService components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Using WebService components
Using RemoteObject components
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Explicit parameter passing and parameter binding
Handling service results
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
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Chapter 1: Accessing data services
overview
Data access in Flex compared to other technologies
The way that Flex works with data sources and data is different from applications that use HTML for their user
interface.
Client-side processing and server-side processing
Unlike a set of HTML templates created using JSPs and servlets, ASP, PHP, or CFML, Flex separates client code from
server code. The application user interface is compiled into a binary SWF file that is sent to the client.
When the application makes a request to a data service, the SWF file is not recompiled and no page refresh is required.
The remote service returns only data. Flex binds the returned data to user interface components in the client
application.
For example, in Flex, when a user clicks a Button control in an application, client-side code calls a web service. The
result data from the web service is returned into the binary SWF file without a page refresh. Thus, the result data is
available to use as dynamic content in the application.
<?xm l version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/halo" minWidth="1024" minHeight="768"
xmlns:employeesservice="services.employeesservice.*" xmlns:valueObjects="valueObjects.*">
<fx:Declarations>
<s:WebService
id="RestaurantSvc"
wsdl="http://examples.adobe.com/flex3app/restaurant_ws/RestaurantWS.xml?wsdl" />
<s:CallResponder id="getRestaurantsResult"
result="restaurants = getRestaurantsResult.lastResult as Restaurant"/>
</fx:Declarations>
<fx:Script>
<![CDATA[
import mx.controls.Alert;
protected function b1_clickHandler(event:MouseEvent):void {
getRestaurantsResult.token = RestaurantWS.getRestaurantss();
}
]]>
</fx:Script>
. . .
<s:Button id="b1" label="GetRestaurants" click="button_clickHandler(event)"/>
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ACCESSING DATA WITH FLEX
Accessing data services overview
Compare this Flex example to the following example, which shows JSP code for calling a web service using a JSP
custom tag. When a user requests the JSP, the web service request is made on the server instead of on the client. The
result is used to generate content in the HTML page. The application server regenerates the entire HTML page before
sending it back to the user's web browser.
<%@ taglib prefix="web" uri="webservicetag" %>
<% String str1="BRL";
String str2="USD";%>
<!-- Call the web service. -->
<web:invoke
url="http://www.itfinity.net:8008/soap/exrates/default.asp"
namespace="http://www.itfinity.net/soap/exrates/exrates.xsd"
operation="GetRate"
resulttype="double"
result="myresult">
<web:param name="fromCurr" value="<%=str1%>"/>
<web:param name="ToCurr" value="<%=str2%>"/>
</web:invoke>
<!-- Display the web service result. -->
<%= pageContext.getAttribute("myresult") %>
Data source access
Another difference between Flex and other web application technologies is that you never communicate directly with
a data source in Flex. You use a data access component to connect to a remote service and to interact with the serverside data source.
The following example shows a ColdFusion page that accesses a data source directly:
...
<CFQUERY DATASOURCE="Dsn"
NAME="myQuery">
SELECT * FROM table
</CFQUERY>
...
To get similar functionality in Flex, use an HTTPService, a web service, or a RemoteObject component to call a serverside object that returns results from a data source.
Events, service calls, and data binding
Flex is an event driven technology. A user action or a program event can trigger access to a service. For example, a user
clicking a button is a user action event that can be used to trigger a service call. An example of a program event is when
the application completes the creation of a user interface component such as a DataGrid. The creationComplete event
for the DataGrid can be used to call a remote service to populate the DataGrid.
Service calls in Flex are asynchronous. The client application does not have to wait for returned data. Asynchronous
service calls are useful when retrieving or updating large sets of data. The client application is not blocked waiting for
the data to be retrieved or updated.
Data returned from a service call is stored in a CallResponder that you associate with the service call. User interface
components then use data binding to retrieve the returned data from the CallResponder.
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ACCESSING DATA WITH FLEX
Accessing data services overview
Data binding in Flex allows you to dynamically update a user interface component with a data source. For example, a
Flex component can associate its text attribute with the lastResult attribute of a CallResponder. When the data in the
CallResponder changes, the Flex component automatically updates.
Flex also implements two-way data binding. With two-way data binding, when data changes in either the Flex
component or the data source, the corresponding data source or Flex component automatically updates. Two-way
data binding is useful when updating remote data from user inputs to a Form component or a Flex data component.
More Help topics
“Building data-centric applications with Flash Builder” on page 7
Using Flash Builder to access data services
In Flex Builder 3, you implement remote procedure calls to data services using Flex data access components. However,
Flash Builder simplifies this process.
Flash Builder provides wizards and other tools that:
• Provide access to data services
• Configure data returned by the data service
• Assist in paging of data returned from the service
• Assist in data management functionality that synchronizes multiple updates to server data
• Generates client code for accessing data services
• Bind data returned from the service to user interface components
Flash Builder workflow for accessing services
Use the following workflow when using Flash Builder to create an application that accesses data services.
1 Depending on your circumstances, you start by connecting to a data service or by building the user interface.
Connect to remote service. If you start by connecting to the remote service, you then build the user interface.
Build user interface. If you start by building the user interface, you then connect to the remote service.
Note: Where you start is a matter of personal preference. For example, if you already have a user interface design
planned, you can build the user interface first. Conversely, you can connect to the data first and let Flash Builder assist
you in generating application components.
2 Bind data operations to application components.
3 (Optional) Manage the retrieval and update of data.
Flash Builder tools allow you to implement the paging of returned data and coordinate the update of sets of data.
When returning large amounts data records, you typically implement paging to retrieve a set of records on an “as
needed” basis.
For applications that updates several records, you can implement data management features. Data Management
features include:
• Commit functionality to update changed records simultaneously
• An undo mechanism to revert changes before they are written to the server
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ACCESSING DATA WITH FLEX
Accessing data services overview
• Code generation that automatically updates user interface components as records are added, deleted, or changed
4 Run the application and monitor the data flow.
When the application is complete, run the application to view it in operation. Use the Flash Builder Network
Monitor to view data passed between the application and the service. The Network Monitor is useful for diagnosing
errors and analyzing performance.
Flash Builder also provides robust debugging and profiling environments. The Network Monitor and Flash Profiler
are available with Flash Builder Premium.
More Help topics
“Building data-centric applications with Flash Builder” on page 7
Extending services supported by Flash Builder
Flash Builder wizards and tools support access to the following type of service implementations:
• PHP services
• ColdFusion services
• BlazeDS
• LiveCycle Data Services
• HTTP (REST-style) services
• Web services (SOAP)
• Static XML files
If you need tooling support for additional types of services, such as Ruby on Rails, you can extend the Flash Builder
implementation. See Flash Builder Extensibility Reference.
Data access components
Data access components let a client application call operations and services across a network. Data access components
use remote procedure calls to interact with server environments. The three data access components are the
RemoteObject, HTTPService, and WebService components.
Data access components are designed for client applications in which a call and response model is a good choice for
accessing external data. These components let the client make asynchronous requests to remote services that process
the requests, and then return data to your application.
A data access component calls a remote service. It then stores response data from the service in an ActionScript object
or any other format the service returns. Use data access components in the client application to work with three types
of services:
• remote object services (RemoteObject)
• SOAP-based web services (WebService)
• HTTP services, including REST-based web services (HTTPService)
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ACCESSING DATA WITH FLEX
Accessing data services overview
Adobe® Flash® Builder™ provides wizards and tools to wrap the implementation of a data access component into a
service wrapper. The service wrapper encapsulates the functionality of the data access component, shielding you from
much of the lower-level implementation. This allows you to concentrate on implementing services and building client
applications to access the services. For more information on using Flash Builder to access data services, see “Building
data-centric applications with Flash Builder” on page 7.
Providing access to services
By default, Adobe Flash Player blocks access to any host that is not exactly equal to the one used to load an application.
If you do not use a server side application, such as LiveCycle Data Services or BlazeDS, to proxy requests, an HTTP
service or web service must either be on the server hosting your application, or the remote server that hosts the HTTP
or web service must define a crossdomain.xml file. A crossdomain.xml file provides a way for a server to indicate
that its data and documents are available to SWF files served from certain domains, or from all domains. The
crossdomain.xml file must be in the web root of the server that the application is contacting.
HTTPService components
Use HTTPService components to send HTTP GET or POST requests and include the data from HTTP responses in a
client application. If you are using Flex to build desktop applications (runs in Adobe AIR®), HTTP PUT and DELETE
are supported.
If you use LiveCycle Data Services or BlazeDS, you can use an HTTPProxyService, which allows you to to use
additional HTTP methods. With an HTTPProxyService, you can send GET, POST, HEAD, OPTIONS, PUT, TRACE,
or DELETE requests.
An HTTP service can be any HTTP URI that accepts HTTP requests and sends responses. Another common name for
this type of service is a REST-style web service. REST stands for Representational State Transfer and is an architectural
style for distributed hypermedia systems.
HTTPService components are a good option when you cannot expose the same functionality as a SOAP web service
or a remote object service. For example, you can use HTTPService components to interact with JavaServer Pages
(JSPs), servlets, and ASP pages that are not available as web services or Remoting Service destinations.
When you call the HTTPService object’s send() method, it makes an HTTP request to the specified URI, and an
HTTP response is returned. Optionally, you can pass arguments to the specified URI.
Flash Builder provides workflows that allow you to interactively connect to HTTP services. For more information, see
“Accessing HTTP services” on page 11.
More Help topics
“Accessing HTTP services” on page 11
Dissertation: Representational State Transfer (REST) by Roy Thomas Fielding
WebService components
WebService components let you access SOAP web services, which are software modules with methods. Web service
methods are commonly called operations. Web service interfaces are defined using Web Services Description
Language (WSDL). Web services provide a standards-compliant way for software modules that are running on various
platforms to interact with each other. For more information about web services, see the web services section of the
World Wide Web Consortium website at www.w3.org/2002/ws/.
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Accessing data services overview
Client applications can interact with web services that define their interfaces in a Web Services Description Language
(WSDL) document, which is available as a URL. WSDL is a standard format for describing the messages that a web
service understands, the format of its responses to those messages, the protocols that the web service supports, and
where to send messages.
Flex supports WSDL 1.1, which is described at www.w3.org/TR/wsdl. Flex supports both RPC-encoded and
document-literal web services.
Flex supports web service requests and results that are formatted as SOAP messages and are transported over HTTP.
SOAP provides the definition of the XML-based format that you can use for exchanging structured and typed
information between a web service client, such as an application built with Flex, and a web service.
You can use a WebService component to connect to a SOAP-compliant web service when web services are an
established standard in your environment. WebService components are also useful for objects that are within an
enterprise environment, but not necessarily available on the source path of the web application.
Flash Builder provides workflows that allow you to interactively connect to web services. For more information, see
“Accessing web services” on page 15.
RemoteObject components
Remote object services let you access business logic directly in its native format rather than formatting it as XML, as
you do with REST-style services or web services. This saves you the time required to expose existing logic as XML.
Another benefit of remote object services is the speed of communication across the wire. Data exchanges still happen
over HTTP or https, but the data itself is serialized into a binary representation. Using RemoteObject components
results in less data going across the wire, reduced client-side memory usage, and reduced processing time.
ColdFusion, PHP, BlazeDS, and LiveCycle Data Services can use server-side typing when accessing data on the server.
The client application accesses a Java object, ColdFusion component (which is a Java object internally), or PHP class
directly by remote invocation of a method on a designated object. The object on the server uses its own native data
types as arguments, queries a database with those arguments, and returns values in its native data types.
When server-side typing is not available, Flash Builder has tools to implement client-side typing. Use the Flash Builder
to configure and define types for data returned from the service. Client-side typing allows the client application to
query a database and retrieve properly typed data. Client-side typing is required for any service that does not define
the type of data returned by the service.
Flash Builder provides workflows that allow you to interactively connect to remote object services. For more
information, see “Connecting to data services” on page 8.
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Chapter 2: Building data-centric
applications with Flash Builder
Flash Builder tools can assist you in creating applications that access data services. You start by creating a Flex project
for your applications. You can then connect to a data service, configure the access of data from the service, and build
a user interface for an application. In some cases, you first create the user interface and then access the data service.
Creating a Flex project to access data services
Flex accesses data services as a remote object, an HTTP (REST-style) service, or a SOAP web service.
You use a remote object to access the following types of data services:
• ColdFusion services
• AMF-based PHP services
• BlazeDS
• LiveCycle Data Services
For information on using the LiveCycle Service Discovery wizard, see Using LiveCycle Discovery.
For any service accessed as a remote object, create a Flex project configured for the appropriate application server type.
The New Flex Project wizard guides you through configuring a project for the application server types listed below:
Server Type
Remote Object Services Supported
PHP
•
AMF-based PHP services
ColdFusion
•
ColdFusion Flash Remoting
•
BlazeDS
•
LiveCycle Data Services
•
BlazeDS
•
LiveCycle Data Services
J2EE
You can connect to HTTP (REST-style) services and SOAP web services from any Flex project configuration,
including projects that do not specify a server technology.
A project configured to access a remote object can only access a remote object service for which it is configured. For
example, you cannot access an AMF-based PHP service from a project configured for ColdFusion. However, you could
connect to a PHP service from this project if you connect to the PHP service as a web service or HTTP service.
More Help topics
“Accessing data services overview” on page 1
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Building data-centric applications with Flash Builder
Changing the server type of a project
Flash Builder notifies you if you attempt to access a service for which a Flex project is not configured. If the Flex project
does not specify the correct server configuration, Flash Builder provides a link to the Project Properties dialog. In the
Project Properties dialog, you can configure the project to access the data service. For example, Flash Builder warns
you if you attempt to access an AMF-based PHP service from a project that does not specify a server configuration.
If the Flex project has previously been configured to access a different type of service, configure a new Flex project or
change the configuration of the current project. If you change the server configuration of a project, then you can no
longer access any services previously configured. For example, if you change a project configuration from ColdFusion
to PHP, any ColdFusion services you access in the project are no longer available.
If you want to access different types of services from the same project, you can access the services as either HTTP
services or web services.
Cross-domain policy file
A cross-domain policy file is necessary when accessing services that are on a different domain from the SWF file for
the application. Typically, AMF-based services do not need a cross-domain policy file because these services are on the
same domain as the application.
Connecting to data services
Use the Flash Builder Service wizard to connect to data services.
For remote object services, you typically create a Flex project with the corresponding application server type. Flash
Builder introspects the service and can configure return types for data returned by the service.
Remote object services include data services implemented in ColdFusion, PHP, BlazeDS, and LiveCycle Data Services.
For information on using the LiveCycle Service Discovery wizard, see Using LiveCycle Discovery.
More Help topics
“Creating a Flex project to access data services” on page 7
Accessing ColdFusion services
Use the Flash Builder Service wizard to access a ColdFusion data service that has been implemented as a ColdFusion
component (CFC). Flex accesses these services as remote objects.
Use a Flex project that specifies ColdFusion as the application server type. When creating the Flex project, specify Use
Remote Object Access Service and use ColdFusion Flash Remoting.
Connecting to ColdFusion data services
This procedure assumes that you have implemented a ColdFusion service and have created a Flex project for accessing
ColdFusion services.
1 From the Flash Builder Data menu, select Connect to ColdFusion to open the Service window.
2 In the Configure ColdFusion Service dialog, browse to the location of the CFC implementing the service.
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Note: If you have not implemented a ColdFusion service, Flash Builder can generate a sample service from a single
database table. Use the generated sample as an example of how to access data services. See “Generating a sample
ColdFusion service from a database table” on page 9.
3 (Optional) Modify the service details.
Service Name
Specify a name for the service.
Flash Builder generates a name for the service, based on the filename for the service.
There are restrictions to names you can use for a service. See “Naming data services” on page 19.
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Data Types Package
Specify a name for the package that contains generated ActionScript class files that define data types
retrieved from the service.
By default, Flash Builder creates the valueObjects package.
4 (Optional) Click Next to view the service operations.
5 Click Finish to generate ActionScript files that access the service.
Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
Next step: “Configuring data types for data service operations” on page 25.
Generating a sample ColdFusion service from a database table
Flash Builder can generate a sample ColdFusion service that you can use as a prototype for your own services. The
sample service accesses a single database table and has methods for create, read, update, and delete.
Flash Builder configures return data types for the generated services and enables data access functionality such as
paging and data management.
Important: Use the generated service only in a trusted development environment. The generated code allows anyone with
network access to your server to be able to access, modify, or delete data in the database table. Before deploying this
service, be sure to increase security and restrict access appropriately. For information on writing secure services, see
Securing Data Services.
The following procedure assumes that you have created a Flex project for accessing ColdFusion services and have
ColdFusion data sources available.
1 From the Flash Builder Data menu, select Connect to ColdFusionto open the Service wizard.
2 In the Configure ColdFusion Service dialog, click the link to generate a sample service.
3 Select Generate from RDS Datasource and specify a ColdFusion Data Source and Table.
If the table does not define a primary key, select a Primary Key for the table.
Note: If you do not have ColdFusion data source available, select Generate from Template. Flash Builder writes a
sample ColdFusion component (CFC) with typical service operations. Uncomment specific functions in the CFC and
modify the operations to create a sample service that you can use as a prototype.
4 Use the default location or specify a new location. Click OK.
Flash Builder generates the sample service. Modify the Service Name and package locations to override the default
values.
5 (Optional) Click Next to view operations in the service.
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ACCESSING DATA WITH FLEX
Building data-centric applications with Flash Builder
6 Click Finish.
Flash Builder generates ActionScript files that access the sample service. Flash Builder also opens the sample service
in an editor on your system that is registered to edit ColdFusion CFC files.
Accessing PHP services
Use the Flash Builder Service wizard to connect to data services implemented in PHP. Flex uses Action Message
Format (AMF) to serialize data between the client application and the data service. Flash Builder installs the Zend AMF
framework to provide access to services implemented in PHP. See “Installing Zend Framework” on page 19.
Access PHP data services from a Flex project that specifies PHP as the application server type. The data service must
be available under the web root you specified when configuring the project for PHP. Place the service in a services
directory, as listed below:
<webroot>/MyServiceFolder/services
More Help topics
“Creating a Flex project to access data services” on page 7
Connecting to PHP data services
This procedure assumes that you have implemented a PHP service and have created a Flex project for accessing PHP
services.
1 From the Flash Builder Data menu, select Connect to PHPto open the Service wizard.
2 In the Configure PHP Service dialog, browse to the PHP file implementing the service:
Note: If you have not implemented a PHP service, Flash Builder can generate a sample service from a single database
table. Use the generated sample as an example of how to access data services. See “Generating a sample PHP service
from a database table” on page 11.
3 (Optional) Modify the service details.
Service Name
Specify a name for the service.
Flash Builder generates a name for the service, based on the filename for the service.
There are restrictions to names you can use for a service. See “Naming data services” on page 19.
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Data Types Package
Specify a name for the package that contains generated ActionScript class files that define data types
retrieved from the service.
By default, Flash Builder creates the valueObjects package.
4 Click Next to view the service operations.
If you do not have the supported version of the Zend Framework for accessing PHP services, Flash Builder prompts
you to install the minimal version of the Zend Framework. See “Installing Zend Framework” on page 19.
5 Click Finish.
Flash Builder generates ActionScript files that access the service.
Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
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Next step: “Configuring data types for data service operations” on page 25.
Generating a sample PHP service from a database table
Flash Builder can generate a sample PHP service that you can use as a prototype for your own services. The sample
service accesses a single MySQL database table and has methods for create, read, update, and delete.
Flash Builder configures return data types for the generated services and enables data access functionality such as
paging and data management.
Important: Use the generated service only in a trusted development environment. The generated code allows anyone with
network access to your server to be able to access, modify, or delete data in the database table. Before deploying this
service, be sure to increase security and restrict access appropriately. For information on writing secure services, see
Securing Data Services.
The following procedure assumes that you have created a Flex project for accessing PHP services and have a MySQL
data source available.
1 From the Flash Builder Data menu, select Connect to PHP to open the Service wizard.
2 In the Configure PHP Service dialog, click the link to generate a sample service.
3 Select Generate from Database and specify the information to connect to a database. Click Connect to Database.
Note: If you do not have PHP data source available, select Generate from Template. Flash Builder writes a sample
project with typical service operations. Uncomment specific areas of the project and modify the operations to create a
sample service that you can use as a prototype.
4 Select a table in the database and specify the primary key.
5 Use the default location or specify a new location. Click OK.
If you do not have the supported version of the Zend Framework for accessing PHP services, Flash Builder prompts
you to install the minimal version of the Zend Framework. See “Installing Zend Framework” on page 19.
Flash Builder generates the sample service. Modify the Service Name and package locations to override the default
values.
6 (Optional) Click Next to view operations in the service.
7 Click Finish.
Flash Builder generates ActionScript files that access the sample service. Flash Builder also opens the sample service
in an editor on your system that is registered to edit PHP files.
Accessing HTTP services
Use the Flash Builder Service wizard to connect to REST-based HTTP services. You can connect to HTTP services
from any Flex project. You do not have to specify a server technology for the project.
A cross-domain policy file is necessary when accessing services that are on a different domain from the SWF file for
the client application. See Using cross-domain policy files.
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Configuring HTTP services
When accessing REST-based HTTP services, there are various ways to configure access to the service. The Configure
HTTP Service wizard supports the following:
• Base URL as prefix
Base URL as prefix is convenient if you are accessing multiple operations from a single service. If you specify a base
URL to the service, then for each operation you specify only the relative path to the HTTP operations.
If you want access to multiple services, then you cannot use Base URL.
• URLs with query parameters
When specifying a URL to an operation, you can include the query parameters for the service operations. The
Configure HTTP Service wizard fills the Parameter table with each parameter included in the operation URL.
• RESTful services with delimited parameters
Flash Builder supports access to RESTful services that use delimited parameters instead of GET query parameter.
For example, suppose you use the following URL to access a RESTful service:
http://restfulService/items/itemID
Use curly brackets ({}) to specify the parameters in the operation URL. For example:
http://restfulService/{items}/{itemID}
Then the Configure HTTP Service wizard populates the Parameter Table:
Name
Data Type
Parameter Type
items
String
URL
itemID
String
URL
When specifying RESTful service parameters, the Data Type and Parameter Type are always configured as String
and URL respectively.
Note: You can mix RESTful service parameters with query parameters when specifying the URL to an operation.
• Path to a local file for an operation URL
For an operation URL, you can specify a path to a local file that implements HTTP services. For example, specify
the following for an operation URL:
c:/MyHttpServices/MyHttpService.xml
• Adding GET and POST operations
You can add additional operations when configuring an HTTP service. Click Add in the Operations table to add
operations.
Specify GET or POST for the operation method.
• Adding parameters to an operation
You can add parameters to selected operations in the Operations table. Select the operation in Operations table and
click Add in the Parameters table.
Specify a name and Data Type for the added parameter. The Parameter Type, GET or POST, corresponds to the
operation method.
• Content type for POST operations
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For POST operations, you can specify the content type. The content type can be either application/x-www-formurlencoded or application/xml.
If you choose applicaton/xml for the content type, Flash Builder generates a query parameter that cannot be
edited. strXML is the default name. You specify the actual parameter at runtime.
Name
Data Type
Parameter Type
strXML
String
POST
You cannot add additional parameters for application/xml content type.
Connecting to HTTP services
1 From the Flash Builder Data menu, select Connect to HTTP to open the Service wizard.
2 (Optional) Specify a base URL to use as a prefix to all operations.
3 Under Operations, specify the following for each operation you want to access:
• Specify the operation method (GET or POST)
• URL to the service operation
Include any parameters to the operation in the URL. Use curly brackets ({}) to specify REST-style service
parameters.
Flash Builder supports access to the following protocols:
http://
https://
Standard absolute paths, such as C:/ or /Applications/
• A name for the operation
4 For each operation parameter in a selected URL, specify the Name and Data Type of the parameter
5 (Optional) Click Add or Delete to add or remove parameters to the selected operation.
6 (Optional) Modify the service details.
Service Name
Specify a name for the service.
Flash Builder generates a name for the service, based on the filename for the service.
There are restrictions to names you can use for a service. See “Naming data services” on page 19
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Data Types Package
Specify a name for the package that contains generated ActionScript class files that define data types
retrieved from the service.
By default, Flash Builder creates the valueObjects package.
7 (Optional) Modify the generated package name for the service.
8 Click Finish.
Flash Builder generates ActionScript files that access the service.
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After connecting to the HTTP service, configure the return types for service operations. When configuring the return
type, you also configure the type for parameters to the operation. See “Configuring data types for data service
operations” on page 25.
Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
Next step: “Configuring data types for data service operations” on page 25.
Accessing an XML file implementing HTTP services
You can access a static XML file that implements an HTTP service. The static XML file can be a local file or available
as a URL.
The service uses a GET method that returns an XML response. This feature is useful for learning about HTTP services
in Flex and for prototyping mock data in client applications.
When accessing the service, you specify the node returning the XML response. Flash Builder uses this node to
automatically configure a return type for the data. After connecting to the service, you can bind operations to the
service to user interface components.
Connecting to an XML service file
1 From the Flash Builder Data menu, select HTTP to open the Service wizard.
2 Specify Local File or URL and browse to the file.
3 Select a node in the file that contains the response you want.
Indicate if the response is an Array.
Flash Builder configures a return type for the selected node.
4 Modify the service details.
Service Name
Specify a name for the service.
Flash Builder generates a name for the service, based on the filename for the service.
There are restrictions to names you can use for a service. See “Naming data services” on page 19
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Data Types Package
Specify a name for the package that contains generated ActionScript class files that define data types
retrieved from the service.
By default, Flash Builder creates the valueObjects package.
5 (Optional) Modify the generated package name for the service.
6 Click Finish.
Flash Builder generates ActionScript files that access the service.
Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
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Accessing web services
Use the Flash Builder Service wizard to connect to web services (SOAP). You can connect to web services from any
Flex project. You do not have to specify a server technology for the project.
A cross-domain policy file is necessary when accessing services that are on a different domain from the SWF file for
the client application.
More Help topics
Using cross-domain policy files
Connecting to web services
1 From the Flash Builder Data menu, select Web Service to open the Service wizard.
2 (BlazeDS/Data Services) If you have installed LiveCycle Data Services or BlazeDS, you can access the web service
through a proxy.
Select Through a BlazeDS/Data Services proxy destination.
Specify a destination. Click Next and proceed to step 5.
Note: Accessing web services through a proxy is only enabled if your Flex project specifies J2EE as the application
server type.
3 Enter a URI to the SOAP service.
4 (Optional) Modify the service details.
Service Name
Specify a name for the service.
Flash Builder generates a name for the service, based on the WSDL URI.
There are restrictions to names you can use for a service. See “Naming data services” on page 19
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Data Types Package
Specify a name for the package that contains generated ActionScript class files that define data types
retrieved from the service.
By default, Flash Builder creates the dataValues package.
5 (Optional) Configure the code generation for the service:
Service
Select a service from the services available.
Port
Flash Builder generates a name for the service, based on the WSDL URI.
Operation List
Select the operations from the service that you want to access in your client application.
6 Click Finish.
Flash Builder generates ActionScript files that access the service.
Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
‘After connecting to the web service, configure the return types for service operations. See “Configuring data types for
data service operations” on page 25 for details.
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Accessing BlazeDS
You can only access BlazeDS services if you have installed Adobe® BlazeDS and configured a Remote Development
Services (RDS) server. See the LiveCycle Data Services ES documentation for information on installing and
configuring BlazeDS.
You typically access BlazeDS data services from a Flex project configured with J2EE as the application server type.
More Help topics
“Creating a Flex project to access data services” on page 7
Connecting to BlazeDS services
This procedure assumes that you have installed BlazeDS, configured a Remote Development Server, and have created
a Flex project for accessing BlazeDS services.
1 From the Flash Builder Data menu, select Connect to BlazeDS to open the Service wizard.
2 Select a destination to import.
3 (Optional) Modify the service details.
Service Name
Specify a name for the service.
Flash Builder generates a name for the service, based on the destination.
There are restrictions to names you can use for a service. See “Naming data services” on page 19
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Data Types Package
Specify a name for the package that contains generated ActionScript class files that define data types
retrieved from the service.
By default, Flash Builder creates the valueObjects package.
4 Click Finish.
Flash Builder generates ActionScript files that access the service.
Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
Accessing LiveCycle Data Services
You can only access services available from LiveCycle Data Services if you have installed LiveCycle Data Services and
configured a Remote Development Services (RDS) server. See the LiveCycle Data Services documentation for
information.
You can access LiveCycle Data Services from a Flex project configured with either J2EE or ColdFusion as the
application server type.
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Service types for LiveCycle Data Services
When connecting to LiveCycle Data Services, the following types of data services are available as destinations:
• Remoting service
Remoting services are implemented using AMF typing. These services do not provide server-side data
management. You can use Flash Builder tools to configure client side data management. See “Enabling data
management” on page 31.
• Data service
Data services are services that implement server-side data management. For more information, see your LiveCycle
Data Services documentation.
• Web service
Web services available through a LiveCycle Data Services proxy that is configured as an LiveCycle Data Services
destination. Server-side typing is not typically provided when connecting to a web service.
Data type configuration and data management
Flash Builder provides tools for client side data configuration and client side data management. The Flash Builder tools
that are available depends on the type of the LiveCycle Data Services destination:
• Remoting service
Remoting services implement AMF typing on the service. You do not configure return data types for remoting
service destinations.
However, you can use Flash Builder to generate code for client side data management. See “Enabling data
management” on page 31.
• Data service
Data services implement server-side data types. You do not configure return data type for data service destinations.
Data service destinations also provide server-side data management. You do not use client side data management
with data service destinations.
• Web service
Web service destinations available through a LiveCycle Data Service proxy typically do not implement server side
typing. You can use Flash Builder tools to configure return types for web service operations. See “Configuring data
types for data service operations” on page 25.
You can use Flash Builder to generate code for client side data management. See “Enabling data management” on
page 31.
Connecting to LiveCycle Data Service destinations (Data service and remoting service
destinations)
This procedure assumes that you have installed LiveCycle Data Services, configured a Remote Development Server,
and have created a Flex project for accessing LCDS services.
1 From the Flash Builder Data menu, select Connect to Data/Service to open the Service wizard.
2 In the Select Service Type dialog, select LCDS. Click Next.
3 Provide login credentials, if needed.
4 (Optional) Modify the service details.
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Service Name
You do not provide a service name. Flesh Builder generates a service name. Flash Builder generates a
name for the service, based on the destination.
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Destinations
Specify one or more destinations available from the LiveCycle Data Services server.
Data Types Package
Specify a name for the data type package. this package contains generated ActionScript class files
that define data types retrieved from the service.
By default, Flash Builder creates the valueObjects package.
5 Click Finish.
Flash Builder generates ActionScript files that access the service.
Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
Connecting to LiveCycle Data Service destinations (Web service destinations)
This procedure assumes that you have installed LiveCycle Data Services, configured a Remote Development Server,
and have created a Flex project for accessing DS services.
1 From the Flash Builder Data menu, select Connect to Data/Service to open the Service wizard.
2 In the Select Service Type dialog, select Web Service. Click Next.
3 Select through a LCDS/BlazeDS proxy destination.
4 Provide login credentials, if needed.
5 Select the destination.
6 (Optional) Modify the service details. Click Next.
Service Name
Specify a name for the service.
Flash Builder generates a name for the service, based on the destination name.
There are restrictions to names you can use for a service. See “Naming data services” on page 19
Service Package
Specify a name for the package that contains generated ActionScript files that access the service.
Flash Builder generates a package based on the service name and places it in a services package.
Data Types Package
Specify a name for the package that contains generated ActionScript class files that define data types
retrieved from the service.
By default, Flash Builder creates the dataValues package.
7 (Optional) Configure the code generation for the service:
Service
Select a service and Port from the services and ports available.
Port
Operation List
Select the operations from the service that you want to access in your client application.
8 Click Finish.
Flash Builder generates ActionScript files that access the service.
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Note: After connecting to a service, you can modify the service properties. Select the service in the Data/Services view.
From the context menu, select Properties.
More Help topics
“Creating a Flex project to access data services” on page 7
Naming data services
Data services that are accessed from Flash Builder have restrictions on the names allowed for the service. Some of these
restrictions are not apparent until you compile your application.
The naming guidelines for services are:
• The initial letter of the service cannot be a number.
• Service names cannot be ActionScript keywords.
• Do not use any ActionScript class name, including custom classes, as a service name.
• (PHP only) If a service name contains underscores, Flash Builder cannot import the service.
Note: It is good practice to use service names that are different from the names of your MXML files.
Installing Zend Framework
When initially accessing PHP services, Flash Builder determines if the supported version of the Zend Framework is
installed. If the supported version of the Zend Framework is not found, Flash Builder prompts you to confirm
installation of the Zend Framework. If you accept, then Flash Builder installs a minimal version of the Zend
Framework. If you decline, then manually install the Zend Framework if you are going to access PHP services.
Default Flash Builder installation
Flash Builder installs the Zend Framework into a ZendFramework folder in the root directory of your web server.
<web root>/ZendFramework/
For Flex projects that access PHP services, Flash Builder creates the following configuration files in the project output
folder:
•
amf_config.ini
•
gateway.php
Production servers
For productions servers, Adobe recommends that you move the ZendFramework folder outside the web root. Update
the zend_path variable defined in amf_config.ini.
If the zend_path variable is commented out, uncomment the zend_path variable. Specify the location of your Zend
Framework installation.
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Manual installation of Zend Framework
You can choose to manually install the Zend Framework.
1 Download the latest release of the Zend Framework.
You can install either the minimal or full package. Flash Builder installs the minimal package.
2 Extract the downloaded version to a location on your system.
3 In the Flex project folder for accessing PHP services, update the zend_path variable defined in amf_config.ini.
If the zend_path variable is commented out, uncomment the zend_path variable. Specify the absolute path to the
location of your Zend Framework installation.
Troubleshooting a Zend Framework installation
If you get an error connecting to the Zend Framework, here are some tips in resolving the error.
Manual installation of the Zend Framework
If you manually installed the Zend Framework, examine the zend_path variable in amf_config.ini.
amf_config.ini is in the project output folder.
Check the following:
• Make sure zend_path is uncommented.
• The specified path to your Zend Framework installation is correct:
• The path is an absolute path to a destination on the local files system. You cannot specify a path to a mapped
network resource.
• The path is to the library folder of your Zend Framework installation. Typically, the library folder is in the
following locations:
(Windows) C:\apache\PHPFrameworks/ZendFramework/library
(Mac OS) /user/apache/PHP/frameworks/ZendFramework/library
Flash Builder installation of the Zend Framework
If Flash Builder installed the Zend Framework, check the following:
• The location of the web root folder
Flash Builder installs the Zend Framework in the project’s web root folder. Check the location of the web root
folder. Select Project > Properties> Flex Server.
• Ensure that the web server is configured to use PHP.
• Examine the zend_path variable in amf_config.ini.
amf_config.ini is in the project output folder.
Check the following:
•
zend_path is uncommented.
• The specified path points to the Zend Framework installation at the project’s web root
• The path is an absolute path to a destination on the local files system. You cannot specify a path to a mapped
network resource.
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Using a single server instance
After you connect to a data service, each application in a project can access the service. By default, each application
creates its own service instance when accessing the server.
You can modify this behavior so that there is only a single service instance in a project. Each application in the project
accesses the same service instance. Typically, you create a single server instance when you want to coordinate the
access of data from multiple applications.
You can specify to access a single service instance on a project basis or as a preference for all projects.
Access a single server instance for a project
1 Select Project > Properties > Data/Services
2 Enable the check box for using a single server instance. Click OK.
Specify single server instance as a preference
1 Open the Preferences dialog.
2 Select Flash Builder > Data/Services
3 Enable the check box for using a single server instance. Click OK.
Building the client application
You use the MXML code editor to create a user interface.
After defining the components for the application using the code editor, you can bind data returned from the service
to user interface components. Generate event handlers as needed for user interaction with the application.
You can also generate a Form from service operations that are available in the Data/Services view.
Binding service operations to controls
Use the Bind To Data dialog to bind a service operation to a user interface component.
The Bind to Data dialog is available from the Data menu in toolbar in the Data/Services view.
When you bind a service operation to a component, Flash Builder generates MXML and ActionScript code to access
the service operation from the client application.
Return types for service operations
When binding a service operation to a control, Flash Builder uses the data type of the data returned by the operation.
Often, you configure the return type for a service operation before binding it to a component.
If the return type for a service operation has not been configured, the Bind to Data dialog prompts you to complete
this step.
See “Configuring data types for data service operations” on page 25.
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Bind a DataGrid control to a service operation (Bind to Data dialog)
This procedure assumes that you have connected to a data service.
1 In the Outline view, select the DataGrid control. Or, place your cursor within the <s:DataGrid> tag in the MXML
editor.
2 With the DataGrid selected, open the Bind to Data dialog by selecting Bind to Data from the Flash Builder Data menu.
3 Select New Service Call, then select a Service and Operation.
If you previously bound a service operation to a component, you can use those results. In this case, specify Existing
Call Result and select the operation to use.
4 (Optional) Select Change Return Type:
Select Change Return Type if you want to reconfigure the return type for the service operation.
If the return type for the operation has not been previously configured, select Configure Return Type.
See “Configuring data types for data service operations” on page 25.
5 Click OK.
The DataGrid component changes to show the fields retrieved from the database.
See Configure DataGrid and AdvancedDataGrid components.
6 Save and run the application.
Generating a service call to an operation
Flash Builder can generate an ActionScript method that calls an operation of a service. The method is not bound to a
user interface component, but is available to use in your application code.
In addition to generating the ActionScript method, Flash Builder creates a CallResponder that provides access to the
data returned from the service call. See “Call Responder” on page 35.
Generate a service call to an operation
This procedure assumes that you have connected to a data service.
1 In Data/Services view, select an operation.
2 From the context menu for the operation, select Generate Service Call.
Flash Builder generates a method for calling the operation and displays the generated method in Source mode of
the MXML editor. Flash Builder creates a CallResponder to hold the results of the service call.
This option is also available from the Data/Services toolbar.
Generating a Form for an application
Forms are one of the most common methods that web applications use to collect information from users. Flash Builder
can generate forms for data retrieved from service calls or for custom data types used to access remote data.
When generating a form, Flash Builder creates a Form layout container and adds components to display or edit the
specific data retrieved from the service.
Flash Builder generates the following types of forms.
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Form
Description
Data type
Contains components representing the fields of a data type.
Master-detail Form
The “master” component is typically a data control listing data retrieved from a service.
The “detail” form represents individual items selected in the master component.
Service call
Create two forms. One form specifies the inputs to an operation. The other form displays the returned
data.
When generating a form, specify which fields to include, the type of user interface control to represent each field, and
whether to make the form editable.
Generating a form
This procedure shows how to generate a form for a service call. The procedures for generating other types of forms are
similar.
1 To run the Generate Form wizard, fom the Data/Services view, select an operation. Then, do one of the following:
• From the context menu for the operation, select Generate Form.
• From the Flash Builder Data menu, select Generate Form.
2 In the Generate Form wizard, select Generate Form for Service Call.
3 Select New Service Call or Existing Call Result.
Specify Existing Call Result to use the code previously generated for a service call.
Otherwise, specify New Service Call and select a Service and Operation for the Form.
4 (Optional) Depending on the operation, you have several options on the Form that is generated.
If the Operation accepts parameters, then you can choose to include a form for the parameters.
If the Operation returns a value, then you can choose to include a form for the return value.
You can choose whether to make the form editable or read-only.
5 (Optional) Configure the Input Types or Return Types.
If the operation you select has input parameters or returns a value, you can configure the input type or return types.
Configure the input types and return type for the operation before you can generate the form. If you previously
configured these types, you have the option to configure them again.
See “Configuring data types for data service operations” on page 25.
6 Click Next. In the Property Control Mapping dialog, select which fields to include in the form and the type of
control to represent the data.
7 Click Finish.
When Flash Builder generates Forms, one Form can be placed on top of another Form. To rearrange the generated
Forms, make sure that you select and move a Form, and not a component of the Form.
When Flash Builder places one Form on top of another, it can be confusing on how to select the Form. In the code
editor, select the tag for one of the Forms.
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Generating a master-detail form
To create a master-detail form, first add a data control component to the application and bind the results of an
operation to the control.
For example, add a DataGrid component and bind the results of an operation such as getItems_paged() to the
DataGrid.
1 In the Outline view, select a data control, such as a DataGrid.
2 From the Data menu, select Generate Details Form.
3 Continue generating the Form, as described in Generating a Form.
Generating a form for a data type
To generate a form with components representing the fields of a custom data type, first configure the data type. See
“Configuring data types for data service operations” on page 25.
1 In the Data/Services view, select a custom data type.
2 From the context menu, select Generate Form.
3 Make sure that Generate Form for Data Type is selected.and choose a Data Type.
4 (Optional) You can choose whether to make the form editable.
5 Click Finish.
Generating event handlers to retrieve remote data
When you bind a data service operation to a component, Flash Builder generates an event handler that retrieves data
from the service to populate the component.
For example, if you bind an operation such as getAllItems() to a DataGrid, Flash Builder generates a
creationComplete event handler. The DataGrid references the generated event handler. The results of the call
become the data provider for the DataGrid.
. . .
protected function dataGrid_creationCompleteHandler(event:FlexEvent):void
{
getAllItemsResult.token = productService.getAllItems();
}
. . .
<mx:DataGrid creationComplete="dataGrid_creationCompleteHandler(event)"
dataProvider="{getAllItemsResult.lastResult}">
. . .
</mx:DataGrid>
. . .
When you run the application, after the DataGrid has been created the event handler populates the DataGrid with data
retrieved from the service.
When generating event handlers, you can accept the generated handlers or replace them with others according to your
needs. For example, you can replace the creationComplete event handler on the DataGrid with a
creationComplete handler on the Application.
You can also generate or create event handlers for controls that accept user input, such as Buttons or Text.
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Generate an event handler for a user interface component
1 Create an application that contains a user interface component, such as a DataGrid or a Button.
2 Flash Builder provides Content Assist to help you generate the event handler. Press Control+Space or Cmd+Space
( Mac) and select Generate Event Handler.
3 Flash Builder generates a unique name for the event handler and places the event handler in the Script block.
Flash Builder highlights the generated stub for the event handler in the code editor. Fill in the remaining code for
the event handler. Use Content Assist to help you code the event handler.
Configuring data types for data service operations
When connecting to a data service, Flash Builder needs to know the data type for the data returned by a service
operation. The data types supported are those types recognized by AMF to exchange data with a data service or remote
service.
Many data services define the type of returned data on the server (server-side typing). However, if the server does not
define the type, then the client application must configure the type for returned data (client-side typing).
Service operations that specify parameters must also specify a type corresponding to data accessed on the service. With
client-side typing, you configure the type for input parameters.
When configuring types for client-side typing, Flash builder recognizes only AMF data types. The type can also be a
custom data type representing complex data, or void to indicate the operation does not return any data.
You can configure user-defined types for service operations that return complex data. For example, if you are
retrieving records from an employee database, then you would define a complex data return as Employee. In this case,
the custom data type for Employee would contain entries for each field in the database record.
Data Types for client side typing
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Data Type
Description
ActionScript types
Boolean
Boolean[]
ByteArray
ByteArray[]
Date
Date[]
int
int[]
Number
Number[]
Object
Object[]
String
String[]
No data returned
void
User-defined type
CustomType
CustomType[]
User-defined type (Employee)
Field
Data Type
emp_no
Number
first_name
String
last_name
String
hire_date
Date
birth_date
Date
Authenticating access to services
Typically data services require user authentication before allowing access to the services. PHP, BlazeDS, and
ColdFusion services that provide access using the HTTP protocol can require additional authentication. In some cases,
these types of services require both HTTP and remote authentication.
Flash Builder provides an option for service authentication when you are doing the following:
• Configuring the return type for an operation
See “Configuring the return type for data from an operation” on page 27.
• Using the Test Operation interface
See “Testing service operations” on page 29.
When you specify Authentication Required, Flash Builder opens the Service Authentication dialog. Depending on the
type of service you are accessing, you can specify Basic Authentication or Remote Authentication.
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Basic authentication
Basic authentication provides access to HTTP and web services. Provide the user name and password for access to
these services.
Specify Remember Username and Password if you want Flash Builder to use the specified credentials throughout the
session.
Remote authentication
Remote authentication provides access to remote object services. Remote object services are services implemented as
remote objects using ColdFusion, PHP, BlazeDS, or LiveCycle Data Services.
Flash Builder does not provide the remote authentication login interface for projects that do not implement remote
object services.
Provide the user name and password for access to the remote object services.
Specify Remember Username and Password if you want Flash Builder to use the specified credentials throughout the
session.
Configuring input parameters to an operation
For client side typing, you configure input parameters to operations available from the data service.
The following procedure assumes that you have connected to a data service in Flash Builder, and the data service has
operations that require configurable input parameters.
1 In the Data/Services view, select an operation that contains configurable input parameters. From the context menu
for the operation, select Configure Input Types.
2 In the Configure Input Types dialog, for each argument to the operation, select a data type from the list of available
type. Click OK.
If you previously defined custom return data types for the service, those types are available for selection.
For server-side typing, the service specifies the data type for input parameters.
Configuring the return type for data from an operation
A service that defines data types returned by an operation provides server-side typing. If a service does not define the
data type returned by an operation, then Flash Builder uses client-side typing to define the returned data type.
Flash Builder introspects the data returned from a service operation to determine the data type. When you configure
the return type of an operation, you have two options:
• Auto-detect the Return Type from Sample Data.
If the service implements server-side typing, Flash Builder detects the data type defined by the service.
If the service does not implement server-side typing, Flash Builder creates a custom type for the client application.
For client-side typing, you provide a name for the custom type. Typically, the name describes the data returned. For
example, if the operation returns an array of books from a database table, then you name the type Book.
• Use an existing type
An existing type can be a type defined by the service, an ActionScript type, or a previously defined custom type.
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The procedures Flash Builder uses for introspecting data differs slightly, depending on the type of data service. For
example, the procedure to introspect and configure the return type for an HTTP service differs from the procedure for
PHP or ColdFusion services.
Merging and changing data types
During the introspection of server data, you can merge fields from another data type or create a data type based on an
existing data type. Here are some of the way you can modify a custom data type:
• Use a new name for an existing data type
Use a new name if you plan to use returned data in different ways in the client application.
For example, retrieving employee data that can be used in employee summary and employee detail tables in the
client application.
• Merge fields
You can add returned fields to an existing data type. Adding additional fields is useful when associating data from
multiple sources. For example, for a JOIN operation that returns data retrieved from multiple database tables.
Another example is data received from different services. For example, merging Book data received from both an
HTTP service and a ColdFusion service.
Configuring a custom data type (PHP or ColdFusion services)
This procedure assumes that you have connected to a data service implemented with PHP or ColdFusion.
1 In the Data/Services view, from the context menu for an operation, select Configure Return Type.
2 If the operation has arguments, enter the argument values. Specify the correct data type for the argument.
3 (New or Modified Custom Type) Select Auto Detect Type of Data Returned by this Operation.
If the service requires authentication, select Authentication Required and provide credentials as needed. See
“Authenticating access to services” on page 26.
Flash Builder introspects the operation and builds a custom data type.
Specify a name for the custom data type.
If you have previously defined a custom data type, you can choose to add the returned fields to the definition of the
existing custom data type.
4 (Use Existing Type) Use this option to specify an ActionScript type or a type you previously configured.
5 Click Finish.
Configuring a custom data type (HTTP service)
This procedure assumes that you have connected to an HTTP service.
1 In the Data/Services view, from the context menu for an operation, select Configure Return Type.
2 (New Custom Type) Select Auto Detect Type of Data Returned by this Operation.
If the service requires authentication, select Authentication Required and provide credentials as needed.
Flash Builder introspects the operation and builds a custom data type. Choose a method for Flash Builder to pass
parameter values for the operation and click Next:
• (Enter Parameter Values) For each parameter, specify a value.
You can also specify the data type for a parameter. Flash Builder automatically selects the default data type.
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• (Enter Service URL) Enter the URL to the HTML service, including parameters and values in the URL. For
example:
http://httpserviceaddress/service_operation?param1=94105
• (Enter XML/JSON Response) Copy the XML/JSON response to the text box.
Use this option if you are offline, or if the HTTP service is still under development, but you know the response
from the server.
3 (New Custom Type, continued) Specify a name for a custom data type or select a node from the returned data.
If you select a node for the returned data, Flash Builder creates a custom data type for data returned for that node.
Indicate if the returned data is returned as an array.
If the service returns an XML file, the Select Root drop-down list is enabled. Select a node from the XML file to
specify a data type.
4 (Use Existing Type) Use this option to specify an ActionScript type or a type you previously configured.
5 Click Finish.
Testing service operations
You can use Flash Builder to test service operations and view data returned from an operation. This feature is useful
to verify the behavior of services.
Important: Some operations, such as update and delete, modify data on the server.
Test a service operation
This procedure assumes you connected to a data service.
1 In the Data/Service view, select an operation in a service. From the context menus, select Test Operation.
The Test Operation view opens, displaying the selected operation. If the operation requires input parameters, the
Test Operation view lists the parameters.
2 For any required input parameters, click the Enter Value field and specify a value for the parameter.
If the parameter requires a complex type, click the Ellipsis button in the field to open an Input Argument Editor.
Specify the value in editor.
The Input Argument Editor accepts JSON notation for representing complex types in ActionScript.
3 If authentication is needed from the server, select Authentication Required. Click Test.
Provide authentication credentials as needed. See “Authenticating access to services” on page 26.
Flash Builder displays the data returned from the service.
4 (Optional) In the Test Operation view, select additional services and operations that are available to test.
Managing the access of data from the server
Paging Paging is the incremental retrieval of large data sets from a remote service.
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For example, suppose you want to access a database that has 10,000 records and then display the data in a DataGrid
that has 20 rows. You can implement a paging operation to fetch the rows in 20 set increments. When the user requests
additional data (scrolling in the DataGrid), the next page of records is fetched and displayed.
Data management In Flash Builder, data management is the synchronization of updates to data on the server from
the client application. Using data management, you can modify one or more items in a client application without
making any updates to the server. You then commit all the changes to the server with one operation. You can also
revert the modifications without updating any data.
Data management involves coordinating several operations (create, get, update, delete) to respond to events from the
client application, such as updating an Employee record.
When enabling data management with Flash Builder, Flash Builder also generates code that automatically updates user
interface components. For example, Flash Builder generates code to keep DataGrids synchronized with data on the
server.
Enabling paging
You can enable paging for a data service that implements a paging function with the following signature:
getItems_paged(startIndex:Number, numItems:Number): myDataType
function name
You can use any valid name for the function.
startIndex
The initial row of data to retrieve.
Define the data type for startIndex as Number in the client operation.
numItems
The number of rows of data to retrieve in each page.
Define the data type for numItems as Number in the client operation.
myDataType
The data type returned by the data service.
When implementing paging from a service, you can also implement a count()operation. A count()operation returns
the number of items returned from the service. Flash Builder requires that the count()operation implement the
following signature:
count(): Number
function name
You can use any valid name for the function.
Number
The number of records retrieved from the operation.
Flex uses the count operation to properly display user interface components that retrieve large data sets. For example,
the count() operation helps determine the thumb size for a scroll bar of a DataGrid.
Some remote services do not provide a count()operation. Paging still works, but the control displaying the paged data
does not properly represent the size of the data set.
Paging operations for filtered queries
You can enable paging for queries that filter results from the database. When filtering results in the query, use these
signatures for the paging and count functions.
getItems_pagedFiltered(filterParam1:String, filterParam2:String, startIndex:Number,
numItems:Number): myDataType
countFiltered(filterParam1:String, filterParam2:String)
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filterParam1
Optional filter parameter. This parameter is the same in getItems_PagedFiltered() and countFiltered().
filterParam2
Optional filter parameter. This parameter is the same in getItems_PagedFiltered() and countFiltered().
Here is a code snippet of a getItems_pagedFiltered() function that is implemented in PHP to access a MySQL
database. The code snippet shows how to use the optional filter parameter.
get_Items_paged($expression, $startIndex, $numItems) {
. . .
SELECT * from employees where name LIKE $expression LIMIT $startIndex, $numItems;
. . .
}
Enable paging for an operation
This procedure assumes that you have coded both getItems_paged()and count() operations in your remote service.
It also assumes that you have configured the return data type for the operation, as explained in “Configuring data types
for data service operations” on page 25.
1 In the Data/Services view, from the context menu for the getItems_paged() operation, select Enable Paging.
2 If you have not previously identified a unique key for your data type, specify the attributes that uniquely identify an
instance of this data type. Click Next.
Typically, this attribute is the primary key.
3 (Optional) Specify the number of items to fetch to define a custom page size.
If you do not specify a custom page size, a default page size is set at the service level. The default page size is 20
records per page.
4 (Optional) Specify the count() operation. Click Finish.
The count() operation allows Flash Builder to properly display user interface elements, such as the thumb size for
a scroll bar.
Paging is now enabled for that operation.
In Data/Services View, the signature of the function that implements paging no longer includes the startIndex and
numItems parameters. Flash Builder now dynamically adds these values. Flash Builder determines these values
based on a custom page size you provided or the default page size of 20 records per page.
Enabling data management
To enable data management for a service, the service implements one or more of the following functions. The Data
management feature uses these functions to synchronize updates to data on the remote server:
• Add (createItem)
createItem(item: myDatatype):int
createItem(item: myDatatype):String
createItem(item: myDatatype):myDataType
The return type for createItem() is the type of the primary key of the database.
• Get All Properties (getItem)
getItem(itemID:Number): myDatatype
• Update (updateItem)
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updateItem((item: myDataType):void
updateItem((item: myDataType, originalItem: myDataType):void
updateItem((item: myDataType, originalItem: myDataType, changes: String[]):void
• Delete (deleteItem)
deleteItem(itemID:Number):void
Flash Builder requires these functions to have the following signatures:
function name
You can use any valid name for the function.
item
An item of the data type returned by the data service.
originalItem
itemID
A unique identifier for the item, usually the primary key in the database.
changes[]
An array corresponding to fields in a specified Item. This argument is only used in one version of
updateItem().
myDataType
The data type of the item available from the data service. Typically, you define a custom data type when
retrieving data from a service.
autoCommit flag
Data management allows you to synchronize updates to data on the server. Changes to data made in the client
application are not updated on the server until you call the service.commit() method.
However, if you want to disable this feature, set the autoCommit flag to true. If autoCommit is true, then updates to
server data are not cached, but are made immediately. See “Enabling data management for a service” on page 38.
deleteItemOnRemoveFromFill flag
When you delete items with data management enabled, use the deleteItemOnRemoveFromFill flag. By default, this
flag is set to true. When you delete an item, the item is immediately removed from the database.
Set deleteItemOnRemoveFromFill to false to defer the deletion until the commit() method is called. The following
example shows the code for a creation complete event handler for a DataGrid. If the user deletes a selected Employee
item in the DataGrid, the selected item is not removed from the database until the commit() method is called.
protected function dg_creationCompleteHandler(event:FlexEvent):void
{
employeeService.
getDataManager(employeeService.DATA_MANAGER_EMPLOYEE).autoCommit=false;
employeeService.getDataManager( e m p l
oyeeService.DATA_MANAGER_EMPLOYEE).deleteItemOnRemoveFromFill=
true;
getAllEmployeesResult.token = employeeService.getAllEmployees();
}
Enable data management for an operation
This procedure assumes that you have implemented the required operations in your remote service. It also assumes
that you have configured the return data type for the operations that use a custom data type. See “Configuring data
types for data service operations” on page 25.
1 In the Data/Services view, expand the Data Types node.
2 From the context menu for a data type, select Enable Data Management.
3 If you have not previously identified a unique key for your data type, specify the attributes that uniquely identify an
instance of this data type. Click Next.
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Typically, this attribute is the primary key.
4 Specify the Add, Get All Properties, Update, and Delete operations that you have implemented. Click Finish.
Note: You do not have to implement all of these functions. Implement only those functions required for your
application.
Data management is now enabled for that operation.
Flash Builder code generation for client applications
Flash Builder generates client code that provides access to remote service operations. Flash Builder generates code in
the following circumstances:
• Connecting to a data service
• Refreshing the data service in Data/Services View
• Configuring a return type for an operation
• Binding a service operation to a user interface control
• Enabling paging for a service operation
• Enabling data management for a service
• Generating an event handler or a service call
Service classes
Use the Service wizard to connect to a data service. When you connect to a service, Flash Builder generates an
ActionScript class file that provides access to the service operations.
For services that access a RemoteObject, the generated class extends the RemoteObjectServiceWrapper class. Services
implemented with PHP, ColdFusion, BlazeDS, and LiveCycle Data Services typically access a RemoteObject.
For HTTP services, the generated class extends the HTTPServiceWrapper class.
For web services, the generated class extends WebServiceWrapper class.
Flash Builder bases the name of the generated class file on the name you provided for the service in the Service wizard.
By default, Flash Builder places this class in the main source folder for a project. Typically, this folder is src. The name
of the package is based on the service name. For example, Flash Builder generates the following ActionScript classes
for an EmployeeService class.
- project
|
- src
|
+ (default package)
|
+ services
|
|
|
+employeeservice
|
|
|
+ _Super_EmployeeService.as
|
|
|
+ EmployeeService.as
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The super class contains the implementation for the EmployeeService class.
Never edit the super class, which is a generated class. Modifications you make to the super class can be overwritten.
Any changes you make to the implementation can result in undefined behavior.
In this example, use EmployeeService.as to extend the generated super class and add your implementation.
More Help topics
“Connecting to data services” on page 8
Classes for custom data types
Many remote data services provide server-side typing. These services return complex data as a custom data type.
For remote data services that do not return typed data, Flash Builder provides client-side typing. With client-side
typing, you use the Flash Builder Connect wizard to define and configure the data type for complex data returned by
the service. For example, for a service that returns employee database records, you define and configure an Employee
data type.
Flash Builder generates an ActionScript class for the implementation of each custom data type returned by the service.
Flash Builder uses this class to create value objects, which it then uses to access data from the remote service.
For example, Flash Builder generates the following ActionScript classes for an EmployeeService class that contains an
Employee data type:
- project
|
- src
|
+ (default package)
|
+ services
|
|
|
+employeeservice
|
|
|
+ _Super_EmployeeService.as
|
|
|
+ EmployeeService.as
|
+ valueObjects
|
+ _Super_Employee.as
|
+ Employee.as
The super classes contain the implementation for the EmployeeService and the Employee data type, respectively.
Never edit a generated super class. Modifications you make to the super class can be overwritten. Any changes you
make to the implementation can result in undefined behavior.
In this example, use EmployeeService.as and Employee.as to extend the generated super class and add your
implementation.
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Binding a service operation to a user interface control
“Binding service operations to controls” on page 21 shows how you can bind data returned from service operations to
a user interface control. When you bind a service operation to a control, Flash Builder generates the following code:
• Declarations tag containing a CallResponder and service tag
• Event handler for calling the service call
• Data binding between the control and the data returned from the operation
Declarations tag
A Declarations tag is an MXML element that declares non-default, non-visual properties of the current class. When
binding a service operation to a user interface, Flash Builder generates a Declarations tag containing a CallResponder
and a service tag. The CallResponder and generated service class are properties of the container element, which is
usually the Application tag.
The following example shows a Declarations tag providing access to a remote EmployeeService:
<fx:Declarations>
<s:CallResponder id="getAllEmployeesResult"/>
<employeesservice:EmployeesService id="employeesService"
fault="Alert.show(event.fault.faultString + '\n'
+ event.fault.faultDetail)" showBusyCursor="true"/>
</fx:Declarations>
Call Responder
A CallResponder manages results for calls made to a service. It contains a token property that is set to the Async token
returned by a service call. The CallResponder also contains a lastResult property, which is set to the last successful
result from the service call. You add event handlers to the CallResponder to provide access to the data returned
through the lastResult property.
When Flash Builder generates a CallResponder, it generates an id property based on the name of the service operation
to which it is bound. The following code sample shows CallResponders for two operations of an EmployeeService. The
getAllItems() operation is bound to the creationComplete event handler for a DataGrid. The delete operation is
bound to the selected item in the DataGrid. The DataGrid displays the items retrieved from the getAllItems()
service call immediately after it is created. The Delete Item Button control removes the selected record in the DataGrid
from the database.
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<fx:Script>
<![CDATA[
import mx.events.FlexEvent;
import mx.controls.Alert;
protected function dg_creationCompleteHandler(event:FlexEvent):void
{
getAllItemsResult.token = employeesService.getAllItems();
}
protected function button_clickHandler(event:MouseEvent):void
{
deleteItemResult.token =
employeesService.deleteItem(dg.selectedItem.emp_no);
}
]]>
</fx:Script>
<fx:Declarations>
<s:CallResponder id="getAllItemsResult"/>
<employeesservice:EmployeesService id="employeesService"
fault="Alert.show(event.fault.faultString + '\n'
+ event.fault.faultDetail)" showBusyCursor="true"/>
<s:CallResponder id="deleteItemResult"/>
</fx:Declarations>
<mx:DataGrid id="dg" editable="true"
creationComplete="dg_creationCompleteHandler(event)"dataProvider="{getAllItemsResult.lastRes
ult}">
<mx:columns>
<mx:DataGridColumn headerText="emp_no" dataField="emp_no"/>
<mx:DataGridColumn headerText="last_name" dataField="last_name"/>
<mx:DataGridColumn headerText="hire_date" dataField="hire_date"/>
</mx:columns>
</mx:DataGrid>
<s:Button label="Delete Item" id="button" click="button_clickHandler(event)"/>
Event handlers
When you bind a service operation to a user interface component, Flash Builder generates an event handler for the
CallResponder. The event handler manages the results of the operation. You can also create an event handler in an
ActionScript code block, and reference that event handler from a property of a user interface component.
Typically, you populate controls such as Lists and DataGrids with data returned from a service. Flash Builder, by
default, generates a creationComplete event handler for the control that fires immediately after the control is created.
For other controls, Flash Builder generates a handler for the control’s default event. For example, for a Button, Flash
Builder generates an event for the Button’s click event.
The control’s event property is set to the generated event handler. The following example shows the generated creation
complete event handler for a DataGrid:
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<fx:Script>
<![CDATA[
import mx.events.FlexEvent;
import mx.controls.Alert;
protected function dg_creationCompleteHandler(event:FlexEvent):void
{
getAllItemsResult.token = employeesService.getAllItems();
}
]]>
</fx:Script>
. . .
<mx:DataGrid id="dg" editable="true"
creationComplete="dg_creationCompleteHandler(event)"
dataProvider="{getAllItemsResult.lastResult}">
<mx:columns>
<mx:DataGridColumn headerText="emp_no" dataField="emp_no"/>
<mx:DataGridColumn headerText="last_name" dataField="last_name"/>
<mx:DataGridColumn headerText="hire_date" dataField="hire_date"/>
</mx:columns>
</mx:DataGrid>
You can generate event handlers for controls that respond to user events, such as Buttons. The following example
shows a generated event handler for a Button that populates a DataGrid:
<fx:Script>
<![CDATA[
import mx.events.FlexEvent;
import mx.controls.Alert;
protected function button_clickHandler(event:MouseEvent):void
{
deleteItemResult.token =
employeesService.deleteItem(dg.selectedItem.emp_no);
}
]]>
</fx:Script>
. . .
<s:Button label="Delete Item" id="button" click="button_clickHandler(event)"/>
Data binding
When you build a user interface, you bind service operations to controls. See “Binding service operations to controls”
on page 21.
Flash Builder generates code that binds the data returned from a service operation to the user interface control that
displays the data.
The following example shows the code that Flash Builder generates to populate a DataGrid control. The
getAllItems() operation returns a set of employee records for the custom data type, Employee.
The dataProvider property of the DataGrid is bound to the results stored in the CallResponder, getAllItemsResult.
Flash Builder automatically updates the DataGrid with DataGridColumns corresponding to each field returned for an
Employee record. The headerText and dataField properties of each column are set according to the data returned in
an Employee record.
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<mx:DataGrid creationComplete="datagrid1_creationCompleteHandler(event)"
dataProvider="{getAllItemsResult.lastResult}" editable="true">
<mx:columns>
<mx:DataGridColumn headerText="gender" dataField="gender"/>
<mx:DataGridColumn headerText="emp_no" dataField="emp_no"/>
<mx:DataGridColumn headerText="birth_date" dataField="birth_date"/>
<mx:DataGridColumn headerText="last_name" dataField="last_name"/>
<mx:DataGridColumn headerText="hire_date" dataField="hire_date"/>
<mx:DataGridColumn headerText="first_name" dataField="first_name"/>
</mx:columns>
</mx:DataGrid>
Enabling paging for a service operation
When you enable paging, Flash Builder modifies the implementation of the generated service. When you populate a
data control (such as a DataGrid or a List) with paged data, Flash Builder determines the number of records visible in
the data control and the total number of records in the database. Flash Builder provides these values as arguments to
the service operation that you used to implement paging.
You do not have to modify any client application code after paging is enabled.
See “Enabling paging” on page 30 for more information.
Enabling data management for a service
In Flash Builder, data management is the synchronization of a set of updates to data on the server. You can enable data
management for custom data types returned from the service. With data management enabled, you can modify one or
more items in a client application without making any updates to the server. You can then commit all the changes to
the server with one operation. You can also revert the modifications without updating any data on the server.
“Enabling data management” on page 31 shows how to implement this feature.
When you enable data management, Flash Builder modifies the implementation of the generated service class and the
generated class for custom data types. Flash Builder creates a DataManager to implement this functionality.
Synchronizing updates to server data
When you call service operations for a managed data type, the changes are reflected in the client application. However,
you can specify that data on the server is not updated until you call the DataManager’s commit() method.
When data management is enabled for a service, the service has an autoCommit flag. By default, autoCommit is false.
The autoCommit flag determines whether to commit changes immediately or to wait until service.commit() is
called.
If autoCommit is false, all updates to the service in the client application are cached until you call service.commit().
You can call the service’s revertChanges() method to discard changes.
If autoCommit is true, then updates are sent to the server immediately. You cannot call revertChanges() to discard
changes.
The deleteItemOnRemoveFromFill flag determines whether a deleted item is immediately removed from the database.
If set to true, then the item is not deleted until service.commit() is called.
The following code disables data management synchronization of updates to server data. Changes to data for the
managed type are updated immediately on the server.
bookService.getDataManager(bookService.DATA_MANAGER__BOOK).autoCommit = true;
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The following code enables data management synchronization of updates to server data. Changes to data for the
managed type are not updated until commit() is called for the service. Additionally, deleted items are not removed
from the database until commit() is called.
bookService.getDataManager(bookService.DATA_MANAGER__BOOK).autoCommit = false;
bookService.getDataManager(bookService.DATA_MANAGER__BOOK).deleteItemOnRemoveFromFill= true;
Reverting changes
The DataManager provides a revertChanges() method. The revertChanges() method restores the data displayed
in the client application to the values retrieved from the server before the last commit call.
Call revertChanges() before calling commit()to reverts changes to a managed data type in the client application:
bookService.getDataManager (bookService.DATA_MANAGER_BOOK).revertChanges();
To commit changes made for the managed data type, call the commit() method.
bookService.getDataManager (employeeService.DATA_MANAGER_EMPLOYEE).commit();
You can also call the commit() method directly from the bookService instance. Calling the commit method directly
from the service instance commits all changes for all managed data types.
bookService.commit();
Note: You cannot call revertChanges() directly from the service instance to revert changes to all managed data types.
You can only call it for a specific managed data type.
If you want to override the default behavior for data management, and disable the ability to revert changes, set the
autoCommit to true. For example, if you have an instance of bookService and enabled data management for the Book
data type, set autoCommit to true:
bookService.getDataManager(bookService.DATA_MANAGER__BOOK).autoCommit = true;
Now, changes made to data for the managed type are updated immediately on the server.
Deploying applications that access data services
There are many factors to consider when moving your application from a development environment to a deployment
environment. The process of deploying an application is dependent on your application, your application
requirements, and your deployment environment.
For example, the process of deploying an application on an internal website that is only accessible by company
employees is different from the process for deploying the same application on a public website.
Deploying applications provides an overview of things to consider and includes a Deployment checklist. The checklist
discusses some common system configuration issues that customers have found when deploying applications for
production. The documentation also contains troubleshooting tips to diagnose common deployment problems.
Best practices for coding access to services
Using Flash Builder tools, you can generate client code to access data in a database. This feature is available for both
PHP and ColdFusion. However, this code is for prototyping only. Do not use this code as a template for writing secure
applications.
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By default, this code allows anyone with network access to your server to insert, select, update, or delete from the
database table. Here are some best practices to consider when modifying the generated code or writing any code that
accesses services. See Securing Data Services for additional information.
Remove functions that are not used
Delete or comment out any functions that you do not plan to use within your application.
Add authentication
Add user authentication to ensure that only trusted users can access your database information.
Add authorization checks
If authentication is necessary, then add authorization checks. Even though you authenticated users to your application,
you want to ensure that they are authorized to make specific queries.
For example, you can allow everyone to select but restrict which users have the authority to delete.
Another example is authorizing user A to retrieve their own information using a select query. But prevent user A from
using a select query to access user B’s information.
Data validation
Be sure to add data validation. For example, validate the data provided to any insert statement to ensure that bad or
malicious data does not get accepted by the database.
Client side validation is not able to protect you from someone sending manual requests to your web server. Data
validation protects against hackers and ensures the quality of the information that is stored.
Restrict the amount of data that is retrieved
Select methods can select everything from a table. In some cases, this practice leads to too much information going
over the network. Only retrieve the data that you need.
For example, SELECT * from a user table can return the user name and password over the network.
Consider SSL for sensitive data
Using a secure protocol ensures the privacy of the information you are sending.
Exporting source files with release version of an application
When you export a release build of an application, Flash Builder provides the option Enable View Source. This option
allows users to view the source files that implement the application. For server projects, the source files include the
services folder, which contains the files providing access to your service implementation.
Important: Use caution when including service files with the View Source option. The service files expose details on
accessing your database, and possibly include sensitive information such as user names and password. If services are
included in the View Source option, anyone who has access to the launched application has access to sensitive data.
More Help topics
Flex Security
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Writing secure services
The examples in Adobe documentation, including the tutorials and applications created using Flash Builder code
generation, are instructive in nature. They illustrate how to access data services from a client application. However,
because these examples are designed to ensure clarity, they do not illustrate best practices for secure access to data.
The Flash Builder documentation contains examples, including applications created from generated code. These
examples are to be deployed in a trusted development environment. A trusted development environment can be a local
machine or location inside a firewall. Without additional security measures, anyone with network access also has
access to your database.
Some best practices when writing services include:
• Authenticate the user before calling any method on a service
• Use service authentication to allow only certain users to perform certain actions.
For example, suppose you have an application that allows employee data to be modified through a RemoteObject
call. In this case, use RemoteObject authentication to make sure that only managers can change the employee data.
• Use programmatic security to limit access to services.
• Apply declarative security constraints to entire services.
• When accessing a web service (<mx:WebService>) or HTTP service (<mx:HTTPService>) one of the following
must be true:
• The service implementation is in the same domain as the application that calls it.
• The host system for the service has a crossdomain.xml file that explicitly allows access from the application’s
domain.
More Help topics
Flex Security
Securing Data Services
Writing secure applications
Adobe® Flash® Player runs applications built with Flash. Content is delivered as a series of instructions in binary format
to Flash Player over web protocols in a precisely described SWF file format. The SWF files themselves are typically
hosted on a server and then downloaded to, and displayed on, the client computer when requested. Most of the content
consists of binary ActionScript instructions. ActionScript is the ECMA standards-based scripting language that Flash
uses. ActionScript features APIs designed to allow the creation and manipulation of client-side user interface elements
and for working with data.
The security model for Flex protects both client and the server. Consider the following two general aspects to security:
• Authorization and authentication of users accessing a server’s resources
• Flash Player operating in a sandbox on the client
Flex supports working with the web application security of any J2EE application server. In addition, precompiled
applications in Flex can integrate with the authentication and authorization scheme of any underlying server
technology to prevent users from accessing your applications. The Flex framework also includes several built-in security
mechanisms that let you control access to web services, HTTP services, and server-based resources such as EJBs.
Flash Player runs inside a security sandbox that prevents hijacking of the client by malicious application code.
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Note: SWF content running in Adobe AIR follows different security rules than content running in the browser. For details,
see the Air Security topic in the AIR documentation.
For links to various security topics, see the Security Topic Center at the Adobe Developer Connection.
More Help topics
Flex Security
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Chapter 3: Implementing services for datacentric applications
Action Message Format (AMF)
Flex uses remote object services and AMF to access services implemented in ColdFusion, PHP, BlazeDS, and LiveCycle
Data Services. AMF provides the messaging for exchanging data between a database and the client application.
ColdFusion, BlazeDS, and LiveCycle Data Services each provide an AMF framework for remote object services. For
services implemented in PHP, Flash Builder uses the Zend AMF framework.
ColdFusion and PHP services can provide server-side typing. In server-side typing, the service defines the type of data
returned. However, if the service implementation does not define the return data type, Flash Builder provides clientside typing. Flash Builder samples data from the service, allowing you to configure the return type in the client
application.
Client-side and server-side typing
In Flex, a client application uses the data type of data returned from a service call in methods that access and display
the data.
However, the services examples listed below return untyped data.
• “Implementing ColdFusion services” on page 43
• “Implementing PHP services” on page 50
• “Example implementing services from multiple sources” on page 64
For example, for the getAllEmployees() operation, the service returns an array of untyped objects that represent
records from the database. Flash Builder provides tools that enable client-side typing. Using Flash Builder tools, you
introspect the returned data and define a custom data type for the data.
For the returned object of employee records, you define the custom data type, Employee. Each column of the record
becomes a property of the Employee data type.
Using the Employee custom data type, the client application can access the returned data and display it properly in the
client application.
Flash Builder can also access services that implement server-side typing. For examples of server-side typing, see Flash
Builder server-side type examples.
Implementing ColdFusion services
When implementing services in ColdFusion, implement the services as ColdFusion component (CFC) files. Each CFC
contains functions that provide the service operations.
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You can create ColdFusion services in any IDE, such as Adobe ColdFusion® Builder™. Flash Builder does not provide
an editor optimized for editing ColdFusion files. However, if you open a ColdFusion file in Flash Builder, Flash Builder
launches the application on your system that is associated with ColdFusion files.
Example ColdFusion services
You can implement a basic ColdFusion service by creating a ColdFusion component (CFC) that contains functions
for the service operations. The following example, employeeService.cfc, illustrates an EmployeeService that
implements two functions. The getAllIEmployees() function retrieves all employee records in the database. The
getEmployees() function returns a single employee record based on the emp_no argument to the function.
This example illustrates client-side typing. The service returns untyped data. Flash Builder uses client-side typing to
introspect the returned data and define a data type.
Subsequent examples illustrate how to implement services for paging and data management.
You can also use Flash Builder to access services that implement server-side typing. See “Client-side and server-side
typing” on page 43.
Examples illustrating server-side typing were not available at the time this document was completed. For server-side
typing examples, see Flash Builder server-side type examples.
ColdFusion example implementing a basic service
This example shows how to implement a basic service in ColdFusion. The example is based on code that Flash Builder
generates when accessing a database table. See “Generating a sample ColdFusion service from a database table” on
page 9.
This example implements client-side typing. See “Client-side and server-side typing” on page 43.
For examples of server-side typing, see Flash Builder server-side type examples.
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. Before deploying this service, be sure to increase security and restrict access appropriately. For information
on writing secure ColdFusion services, see the ColdFusion documentation About User Security.
<cfcomponent output="false">
<!--This sample service contains functions that illustrate typical service operations.
This code is for prototyping only.
Authenticate the user prior to allowing them to call these methods. You can find more
information at http://www.adobe.com/go/cf9_usersecurity
--->
<cffunction name="getAllemployees" output="false" access="remote" returntype="any" >
<!--- Retrieve set of records and return them as a query or array.
Add authorization or any logical checks for secure access to your data --->
<cfset var qAllItems="">
<cfquery name="qAllItems" datasource="employees">
SELECT * FROM employees
</cfquery>
<cfreturn qAllItems>
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</cffunction>
<cffunction name="getemployees" output="false" access="remote" returntype="any" >
<cfargument name="emp_no" type = "numeric" required="true" />
<!--- Retrieve a single record and return it as a query or array.
Add authorization or any logical checks for secure access to your data --->
<cfset var qItem="">
<cfquery name="qItem" datasource="employees">
SELECT *
FROM employees
WHERE emp_no = <CFQUERYPARAM CFSQLTYPE="CF_SQL_INTEGER"
VALUE="#ARGUMENTS.emp_no#">
</cfquery>
<cfreturn qItem>
</cffunction>
</cfcomponent>
Highlights of EmployeeService:
• Connects to the employees database and accesses the employees table in the database.
• Returns an array of objects.
When programming using the Flex framework, services return data only. The client application handles the
formatting and presentation of the data. This model differs from traditional ColdFusion CFM applications that
return data formatted in an HTML template.
Flex handles returned recordsets as an array of objects. Each row represents a retrieved record from the database.
Each column of the database record becomes a property of the returned object. The client application can now
access the returned data as objects with a set of properties.
Configure the data type for the returned object. See “Client-side and server-side typing” on page 43.
• The ColdFusion server provides error handling.
The error handling provided by ColdFusion is useful when debugging a service. In the ColdFusion Administrator,
modify the Debugging and Logging settings to provide robust debugging information.
The Flash Builder Test Operation interface displays information returned by ColdFusion server.
See “Debugging remote services” on page 61 for more information on testing services.
• Uses cfqueryparam for constructing database queries.
cfqueryparam is a defense against SQL injection statements in calls to the server. For more information, see
Enhancing security with cfqueryparam in the ColdFusion documentation.
• Authenticate users before providing access to the functions in this service.
The sample code does not illustrate how to authenticate users. See the ColdFusion documentation, About User
Security.
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More Help topics
“Configuring data types for data service operations” on page 25
“Accessing ColdFusion services” on page 8
“Generating a sample ColdFusion service from a database table” on page 9
ColdFusion example implementing paging
Flash Builder tools allow you to implement paging of data retrieved from a remote service. Paging is the incremental
retrieval of large data sets.
Flash Builder requires specific function signatures to implement paging. The following code example provides an
example of one way to implement a ColdFusion service for paged data.
The EmployeeServicePaged example is based on the code generated by Flash Builder when accessing a database table.
See “Generating a sample ColdFusion service from a database table” on page 9.
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. The example allows anyone with network access to your server to be able to access, modify, or delete data
in the database table. Before deploying this service, be sure to increase security and restrict access appropriately. For
information on writing secure ColdFusion services, see the ColdFusion documentation About User Security.
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<cfcomponent output="false">
<!--This sample service contains functions that illustrate typical service operations.
This code is for prototyping only.
Authenticate the user prior to allowing them to call these methods. You can find more
information at http://www.adobe.com/go/cf9_usersecurity
--->
<cffunction name="count" output="false" access="remote" returntype="numeric" >
<!---
Return the number of items in your table.
Add authorization or any logical checks for secure access to your data --->
<cfquery name="qread" datasource="employees">
SELECT COUNT(emp_no) AS itemCount FROM employees
</cfquery>
<cfreturn qread.itemCount>
</cffunction>
<cffunction name="getemployees_paged" output="false" access="remote" returntype="any" >
<cfargument name="startIndex" type="numeric" required="true" />
<cfargument name="numItems" type="numeric" required="true" />
<!---Return a page of numRows number of records as an array or
query from the database for this startRow.
Add authorization or any logical checks for secure access to your data --->
<!---The LIMIT keyword is valid for mysql database only.
Modify it for your database --->
<cfset var qRead="">
<cfquery name="qRead" datasource="employees">
SELECT * FROM employees LIMIT #startIndex#, #numItems#
</cfquery>
<cfreturn qRead>
</cffunction>
</cfcomponent>
The EmployeeServicePaged service returns untyped data. Use the Flash Builder tools to configure the return type for
getEmployees_Paged(). After configuring the return type, enable paging on the getEmployees_Paged() operation.
More Help topics
“Example ColdFusion services” on page 44
“Configuring data types for data service operations” on page 25
“Managing the access of data from the server” on page 29
ColdFusion example implementing data management operations
Flash Builder tools allow you to implement data management functionality for remote services. Data management is
the synchronization of updates to data on a server from the client application.
Flash Builder requires a combination of specific function signatures to implement data management. The following
code example provides an example of one way to implement a ColdFusion service for data management.
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The following EmployeeServiceDM example is based on the code generated by Flash Builder when accessing a
database table. See “Generating a sample ColdFusion service from a database table” on page 9.
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. Before deploying this service, be sure to increase security and restrict access appropriately. For information
on writing secure ColdFusion services, see the ColdFusion documentation About User Security.
<cfcomponent output="false">
<!--This sample service contains functions that illustrate typical service operations.
This code is for prototyping only.
Authenticate the user prior to allowing them to call these methods. You can find more
information at http://www.adobe.com/go/cf9_usersecurity
--->
<cffunction name="getAllemployees" output="false" access="remote" returntype="any" >
<!--- Auto-generated method
Retrieve set of records and return them as a query or array.
Add authorization or any logical checks for secure access to your data --->
<cfset var qAllItems="">
<cfquery name="qAllItems" datasource="employees">
SELECT * FROM employees
</cfquery>
<cfreturn qAllItems>
</cffunction>
<cffunction name="getemployees" output="false" access="remote" returntype="any" >
<cfargument name="emp_no" type = "numeric" required="true" />
<!--Retrieve a single record and return it as a query or array.
Add authorization or any logical checks for secure access to your data --->
<cfset var qItem="">
<cfquery name="qItem" datasource="employees">
SELECT *
FROM employees
WHERE emp_no = <CFQUERYPARAM CFSQLTYPE="CF_SQL_INTEGER"
VALUE="#ARGUMENTS.emp_no#">
</cfquery>
<cfreturn qItem>
</cffunction>
<cffunction name="createemployees" output="false" access="remote" returntype="any" >
<cfargument name="item" required="true" />
<!--Insert a new record in the database.
Add authorization or any logical checks for secure access to your data --->
<cfquery name="createItem" datasource="employees" result="result">
INSERT INTO employees (birth_date, first_name, last_name, gender, hire_date)
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VALUES (<CFQUERYPARAM cfsqltype="CF_SQL_DATE" VALUE="#item.birth_date#">,
<CFQUERYPARAM cfsqltype="CF_SQL_VARCHAR"
VALUE="#item.first_name#">,
<CFQUERYPARAM cfsqltype="CF_SQL_VARCHAR"
VALUE="#item.last_name#">,
<CFQUERYPARAM cfsqltype="CF_SQL_CHAR" VALUE="#item.gender#">,
<CFQUERYPARAM cfsqltype="CF_SQL_DATE" VALUE="#item.hire_date#">)
</cfquery>
<!--- The GENERATED_KEY is valid for mysql database only, you can modify it for your
database --->
<cfreturn result.GENERATED_KEY/>
</cffunction>
<cffunction name="updateemployees" output="false" access="remote" returntype="void" >
<cfargument name="item" required="true" />
<!--- Update an existing record in the database.
Add authorization or any logical checks for secure access to your data --->
<cfquery name="updateItem" datasource="employees">
UPDATE employees SET birth_date = <CFQUERYPARAM cfsqltype=CF_SQL_DATE
VALUE="#item.birth_date#">,
first_name = <CFQUERYPARAM cfsqltype=CF_SQL_VARCHAR
VALUE="#item.first_name#">,
last_name = <CFQUERYPARAM cfsqltype=CF_SQL_VARCHAR
VALUE="#item.last_name#">,
gender = <CFQUERYPARAM cfsqltype=CF_SQL_CHAR
VALUE="#item.gender#">,
hire_date = <CFQUERYPARAM cfsqltype=CF_SQL_DATE
VALUE="#item.hire_date#">
WHERE emp_no = <CFQUERYPARAM CFSQLTYPE="CF_SQL_INTEGER" VALUE="#item.emp_no#">
</cfquery>
</cffunction>
<cffunction name="deleteemployees" output="false" access="remote" returntype="void" >
<cfargument name="emp_no" type="numeric" required="true" />
<!--- Delete a record in the database.
Add authorization or any logical checks for secure access to your data --->
<cfquery name="delete" datasource="employees">
DELETE FROM employees
WHERE emp_no = <CFQUERYPARAM CFSQLTYPE="CF_SQL_INTEGER"
VALUE="#ARGUMENTS.emp_no#">
</cfquery>
</cffunction>
</cfcomponent>
The EmployeeServiceDM service returns untyped data. Use the Flash Builder tools to configure the return type for
getAllEmployeess() and getEmployees(). Use Employee for the custom data type returned by these operations.
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After configuring the return type, enable data management on the Employee data type.
More Help topics
“Example ColdFusion services” on page 44
“Configuring data types for data service operations” on page 25
“Managing the access of data from the server” on page 29
Generating CFCs using Adobe ColdFusion Builder
Adobe® ColdFusion® Builder™ provides the Adobe CFC Generator. Use CFC Generator to generate an ORM CFC or a
traditional CFC from a set of database tables. The CFC generated by ColdFusion Builder can then be used as a data
service in Flash Builder. The Adobe CFC Generator creates services that implement server side typing.
For details, see Using Adobe CFC Generator.
Note: ColdFusion object relational mapping (ORM uses an object model to define a mapping strategy for storing and
retrieving data from a relational database. See ColdFusion ORM.
Implementing PHP services
When implementing services in PHP, you typically implement the services as PHP classes. The classes in PHP do not
necessarily have to be object-oriented classes. Rather, each class can be a library of functions that provide the service
operations.
You can create PHP services in any editing environment, such as Dreamweaver or Zend Studio. Flash Builder does not
provide an editor optimized for editing PHP files. However, if you open a PHP file in Flash Builder, Flash Builder
launches the application on your system that is associated with PHP files. For convenience, Flash Builder also provides
a plain text editor that you can use to edit the PHP files.
Using AMF to access services implemented in PHP
PHP data services are available using Action Message Format (AMF). AMF provides messaging between a Flash client
and a web server. Flash Builder uses the Zend AMF framework to implement AMF messaging for PHP data services.
For information on Zend AMF, see Zend Framework Programmer's Reference.
For information on installing Zend Framework, see “Installing Zend Framework” on page 19.
For information on using Zend with Flash Builder for PHP, see the Zend website.
Note: Although Flash Builder uses the Zend AMF framework, you are not required to use Zend components when
creating PHP services. Although Zend components work well with Flash Builder, you can also use any PHP development
environment for creating services.
Example PHP services
You can implement a basic PHP service by creating a PHP class file that contains functions for the service operations.
The following example illustrates an EmployeeService that implements two functions:
•
getAllIEmployees()
Retrieves all employee records in the database.
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•
getEmployeeByID($itemID)
Returns a single employee record.
This example illustrates client-side typing. The service returns untyped data. Flash Builder uses client-side typing to
introspect the returned data and define a data type.
Subsequent examples illustrate how to implement services for paging and data management.
You can also use Flash Builder to access services that implement server-side typing. See “Client-side and server-side
typing” on page 43.
Examples illustrating server-side typing were not available at the time this document was completed. For server-side
typing examples, see Flash Builder server-side type examples.
PHP basic service example
This example shows how to implement a basic service in PHP. The example is based on code that Flash Builder
generates when accessing a database table. See “Generating a sample PHP service from a database table” on page 11.
This example illustrates client-side typing. See “Client-side and server-side typing” on page 43.
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. Before deploying this service, be sure to increase security and restrict access appropriately. For information
on writing secure services, see “Deploying applications that access data services” on page 39.
<?php
/**
* This sample service contains functions that illustrate typical service operations.
* This code is for prototyping only.
*
* Authenticate users before allowing them to call these methods.
*/
class EmployeeService {
var
var
var
var
var
var
$username = "root";
$password = "root";
$server = "localhost";
$port = "3306";
$databasename = "employees";
$tablename = "employees";
var $connection;
/**
* The constructor initializes the connection to database. Everytime a request is
* received by Zend AMF, an instance of the service class is created and then the
* requested method is called.
*/
public function __construct() {
$this->connection = mysqli_connect(
$this->server,
$this->username,
$this->password,
$this->databasename,
$this->port
);
$this->throwExceptionOnError($this->connection);
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}
/**
* Returns all the rows from the table.
*
* Add authroization or any logical checks for secure access to your data
*
* @return array
*/
public function getAllEmployees() {
$stmt = mysqli_prepare($this->connection, "SELECT * FROM $this->tablename");
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
$rows = array();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name, $row->gender, $row->hire_date);
while (mysqli_stmt_fetch($stmt)) {
$rows[] = $row;
$row = new stdClass();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name, $row->gender, $row->hire_date);
}
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
return $rows;
}
/**
* Returns the item corresponding to the value specified for the primary key.
*
* Add authroization or any logical checks for secure access to your data
*
*
* @return stdClass
*/
public function getEmployeesByID($itemID) {
$stmt = mysqli_prepare($this->connection, "SELECT * FROM $this->tablename where emp_no=?");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'i', $itemID);
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name, $row->gender, $row->hire_date);
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if(mysqli_stmt_fetch($stmt)) {
return $row;
} else {
return null;
}
}
/**
* Utitity function to throw an exception if an error occurs
* while running a mysql command.
*/
private function throwExceptionOnError($link = null) {
if($link == null) {
$link = $this->connection;
}
if(mysqli_error($link)) {
$msg = mysqli_errno($link) . ": " . mysqli_error($link);
throw new Exception('MySQL Error - '. $msg);
}
}
}
?>
Highlights of EmployeeService:
• Connects to the employees database, which it accesses on port 3306 of localhost. Accesses the employees table in
the database.
• Provides class variables for connecting to the service and accessing the tables in the database.
These variables can be used in functions in the class.
Replace the values for these variables with values for your system.
• Returns the array of objects to the client application.
When programming using the Flex framework, services return data only. The client application handles the
formatting and presentation of the data.
This model differs from traditional PHP services, that return data formatted in an HTML template.
•
getEmployeesByID($itemID) function binds the input parameter to data types.
The number of variables and length of string types must match the parameters in the statement. The ‘?’ in the
prepare statement is a placeholder for the parameter.
mysqli recognizes the following types:
• integer (i)
• double (d)
• string (s)
• blob (b)
• Binds the results, creating an array of objects ($row[]).
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Flex handles recordsets as an array of objects. Each object represents a record retrieved from the database. Each
column of the database record becomes a property of the returned object. The client application can now access the
returned data as objects with a set of properties.
Because the server does not define a data type for the returned data, you configure the data type for the returned
object. See “Client-side and server-side typing” on page 43.
• Provides a constructor function for initializing the connection to the database.
• Uses mysqli prepare statements for constructing database queries.
Using prepare statements is a defense against SQL injection statements in calls to the server. Only after preparing
the statement is the statement executed on the server.
• Authenticate users before providing access to the functions in this service.
The sample code does not illustrate how to authenticate users. See the ColdFusion documentation, About User
Security. The security principles on user authentication and authorization in this ColdFusion documentation apply
to PHP services.
• Throws an exception on error.
Information that you provide in exceptions is useful when debugging the service implementation. The Flash
Builder Test Operation interface displays information returned by exceptions.
See “Debugging remote services” on page 61 for more information on testing services.
• The filename, EmployeeService.php, matches the PHP class name for the service.
If the filename and the class name do not match, you encounter errors when accessing the service.
More Help topics
“Configuring data types for data service operations” on page 25
“Accessing PHP services” on page 10
“Generating a sample PHP service from a database table” on page 11
PHP example implementing paging
Flash Builder tools allow you to implement paging of data retrieved from a remote service. Paging is the incremental
retrieval of large data sets.
Flash Builder requires specific function signatures to implement paging. The following code example provides an
example of one way to implement a PHP service for paged data.
This example is based on the code generated by Flash Builder when accessing a database table. See “Generating a
sample PHP service from a database table” on page 11.
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. Before deploying this service, be sure to increase security and restrict access appropriately. For information
on writing secure services, see “Deploying applications that access data services” on page 39.
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<?php
/**
* This sample service contains functions that illustrate typical service operations.
* This code is for prototyping only.
*
* Authenticate the user prior to allowing them to call these methods.
*
*/
class EmployeeServicePaged {
var
var
var
var
var
var
$username = "root";
$password = "root";
$server = "localhost";
$port = "3306";
$databasename = "employees";
$tablename = "employees";
var $connection;
/**
* The constructor initializes the connection to database. Everytime a request is
* received by Zend AMF, an instance of the service class is created and then the
* requested method is invoked.
*/
public function __construct() {
$this->connection = mysqli_connect(
$this->server,
$this->username,
$this->password,
$this->databasename,
$this->port
);
$this->throwExceptionOnError($this->connection);
}
/**
* Returns the number of rows in the table.
*
* Add authroization or any logical checks for secure access to your data
*
*
*/
public function count() {
$stmt = mysqli_prepare($this->connection, "SELECT COUNT(*) AS COUNT
FROM $this->tablename");
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
mysqli_stmt_bind_result($stmt, $rec_count);
$this->throwExceptionOnError();
mysqli_stmt_fetch($stmt);
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$this->throwExceptionOnError();
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
return $rec_count;
}
/**
* Returns $numItems rows starting from the $startIndex row from the
* table.
*
* Add authroization or any logical checks for secure access to your data
*
* @return array
*/
public function getEmployees_paged($startIndex, $numItems) {
$stmt = mysqli_prepare($this->connection, "SELECT * FROM
$this->tablename LIMIT ?, ?");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'ii', $startIndex, $numItems);
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
$rows = array();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name,
$row->gender, $row->hire_date);
while (mysqli_stmt_fetch($stmt)) {
$rows[] = $row;
$row = new stdClass();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name,
$row->gender, $row->hire_date);
}
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
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return $rows;
}
/**
* Utitity function to throw an exception if an error occurs
* while running a mysql command.
*/
private function throwExceptionOnError($link = null) {
if($link == null) {
$link = $this->connection;
}
if(mysqli_error($link)) {
$msg = mysqli_errno($link) . ": " . mysqli_error($link);
throw new Exception('MySQL Error - '. $msg);
}
}
}
?>
The EmployeeServicePaged service returns untyped data. Use the Flash Builder tools to configure the return type for
getEmployees_Paged(). After configuring the return type, enable paging on the getEmployees_Paged() operation.
More Help topics
“Example PHP services” on page 50
“Configuring data types for data service operations” on page 25
“Managing the access of data from the server” on page 29
PHP example implementing data management
Flash Builder tools allow you to implement data management functionality for remote services. Data management is
the synchronization of updates to data on a server from the client application.
Flash Builder requires a combination of specific function signatures to implement data management. The following
code example provides an example of one way to implement a PHP service for data management.
This example is based on the code generated by Flash Builder when accessing a database table. See “Generating a
sample PHP service from a database table” on page 11.
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. Before deploying this service, be sure to increase security and restrict access appropriately. For information
on writing secure services, see “Deploying applications that access data services” on page 39.
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<?php
/**
* This sample service contains functions that illustrate typical service operations.
* This code is for prototyping only.
*
* Authenticate the user prior to allowing them to call these methods.
*/
class EmployeeServiceDM {
var
var
var
var
var
var
$username = "root";
$password = "root";
$server = "localhost";
$port = "3306";
$databasename = "employees";
$tablename = "employees";
var $connection;
/**
* The constructor initializes the connection to database. Everytime a request is
* received by Zend AMF, an instance of the service class is created and then the
* requested method is invoked.
*/
public function __construct() {
$this->connection = mysqli_connect(
$this->server,
$this->username,
$this->password,
$this->databasename,
$this->port
);
$this->throwExceptionOnError($this->connection);
}
/**
* Returns all the rows from the table.
*
* Add authroization or any logical checks for secure access to your data
*
* @return array
*/
public function getAllEmployees() {
$stmt = mysqli_prepare($this->connection, "SELECT * FROM $this->tablename");
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
$rows = array();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name,
$row->gender, $row->hire_date);
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while (mysqli_stmt_fetch($stmt)) {
$rows[] = $row;
$row = new stdClass();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name,
$row->gender, $row->hire_date);
}
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
return $rows;
}
/**
* Returns the item corresponding to the value specified for the primary key.
*
* Add authroization or any logical checks for secure access to your data
*
*
* @return stdClass
*/
public function getEmployeesByID($itemID) {
$stmt = mysqli_prepare($this->connection, "SELECT * FROM
$this->tablename where emp_no=?");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'i', $itemID);
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name,
$row->gender, $row->hire_date);
if(mysqli_stmt_fetch($stmt)) {
return $row;
} else {
return null;
}
}
/**
* Returns the item corresponding to the value specified for the primary key.
*
* Add authroization or any logical checks for secure access to your data
*
*
* @return stdClass
*/
public function createEmployees($item) {
$stmt = mysqli_prepare($this->connection, "INSERT INTO $this->tablename
(emp_no, birth_date, first_name, last_name,
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gender, hire_date) VALUES (?, ?, ?, ?, ?, ?)");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'isssss', $item->emp_no, $item->birth_date
$item->first_name, $item->last_name,
$item->gender, $item->hire_date);
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
$autoid = mysqli_stmt_insert_id($stmt);
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
return $autoid;
}
/**
* Updates the passed item in the table.
*
* Add authroization or any logical checks for secure access to your data
*
* @param stdClass $item
* @return void
*/
public function updateEmployees($item) {
$stmt = mysqli_prepare($this->connection, "UPDATE $this->tablename
SET emp_no=?, birth_date=?, first_name=?,
last_name=?, gender=?, hire_date=?
WHERE emp_no=?");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'isssssi', $item->emp_no, $item->birth_date,
$item->first_name, $item->last_name, $item->gender,
$item->hire_date, $item->emp_no);
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
}
/**
* Deletes the item corresponding to the passed primary key value from
* the table.
*
* Add authroization or any logical checks for secure access to your data
*
*
* @return void
*/
public function deleteEmployees($itemID) {
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$stmt = mysqli_prepare($this->connection, "DELETE FROM $this->tablename
WHERE emp_no = ?");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'i', $itemID);
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
}
/**
* Utitity function to throw an exception if an error occurs
* while running a mysql command.
*/
private function throwExceptionOnError($link = null) {
if($link == null) {
$link = $this->connection;
}
if(mysqli_error($link)) {
$msg = mysqli_errno($link) . ": " . mysqli_error($link);
throw new Exception('MySQL Error - '. $msg);
}
}
}
?>
The EmployeeServiceDM service returns untyped data. Use the Flash Builder tools to configure the return type for
getAllEmployeess() and getEmployeesByID(). Use Employee for the custom data type returned by these
operations.
After configuring the return type, enable data management on the Employee data type.
More Help topics
“Example PHP services” on page 50
“Configuring data types for data service operations” on page 25
“Managing the access of data from the server” on page 29
Debugging remote services
There are several ways to debug applications that access remote services.
• Flash Builder Test Operation view
The Flash Builder Test Operation view allows you to call service operations and view the returned data. The Test
Operation view displays any error messages displayed by the service.
• Server-side scripts
For additional debugging of services, you can write scripts that test server code and write output stream
information to log files.
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• Flash Builder Network Monitor
Use the Network Monitor after building an application with Flash Builder that accesses a service. Use the Network
Monitor to view data sent between the server and client.
Flash Builder Test Operation view
Use the Flash Builder Test Operation view to call operations from a service and view the results of the operation.
Results include any error messages returned from the service.
You can use the Test Operation view to view data returned from operations on services you write or services available
from HTTP or web services.
Test a service operation
This procedure assumes that you have written a service that you are testing or have access to an HTTP or web service.
1 In the Flash Builder Data/Services view, navigate to a service operation you want to test.
2 From the context menu for the service operation, select Test Operation.
3 (Optional) In the Test Operation view, select Authentication Required to provide login credentials to the service.
4 If the operation takes parameters, click the Enter Value field to provide a value for the parameter.
If the parameter requires a complex type, click the Ellipsis button in the Enter Value field to open an editor that
accepts JSON notation. Provide the value for the parameter using JSON notation.
5 Click Test to view the results of the operation.
Scripts to test server code
Use test scripts to view and debug server code before attempting to connect to the server in Flash Builder. Test scripts
provide the following benefits:
• You can view test results from a web browser.
As you modify the code, simply refresh the browser page to view the results.
• You can echo or print results to the output stream, which you cannot do directly from AMF.
• Error displays are nicely formatted and typically more complete than errors captured using AMF.
ColdFusion Scripts
Use the following script, tester.cfm, to dump a call to a function.
<!--- tester.cfm --->
<cfobject component="EmployeeService" name="o"/>
<cfdump var="#o.getAllItems()#">
In tester2.cfm, you specify the method and arguments to call in the URL.
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<!--- tester2.cfm --->
<cfdump var="#url#">
<cfinvoke component="#url.cfc#" method="#url.method#" argumentCollection="#url#"
returnVariable="r">
<p>Result:
<cfif isDefined("r")>
<cfdump var="#r#">
<cfelse>
(no result)
</cfif>
For example, call the getItemID() method in EmployeeService with the following URL:
http://localhost/tester2.cfm?EmployeeService&method=getItemId&id=12
tester3.cfm writes a log that records calls to operations and dumps the input arguments using cfdump.
<!--- tester3.cfm --->
<cfsavecontent variable="d"><cfdump var="#arguments#"></cfsavecontent>
<cffile action="append"
file="#getDirectoryFromPath(getCurrentTemplatePath())#MyServiceLog.htm"
output="<p>#now()# operationName #d#">
PHP Scripts
Use the following script, tester.php, to dump a call to a function.
<pre>
<?php
include('MyService.php');
$o = new MyService();
var_dump($o->getAllItems());
?>
</pre>
Add the following code to your PHP service to log messages during code execution.
$message = 'updateItem: '.$item["id"];
$log_file = '/Users/me/Desktop/myservice.log';
error_log(date('d/m/Y H:i:s').' '.$message.PHP_EOL, 3, $log_file);
Add the following code to your PHP service to enable dumping to a log file:
ob_start();
var_dump($item);
$result = ob_get_contents();
ob_end_clean();
$message = 'updateItem: '.$result;
$log_file = '/Users/me/Desktop/myservice.log';
error_log(date('d/m/Y H:i:s').' '.$message.PHP_EOL, 3, $log_file);
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Network Monitor
The Network Monitor is available in Flash Builder from the Flex Debugging Perspective. Enable the monitor before
you can use it to monitor data. See Monitor applications that access data services for details about enabling and using
the Network Monitor.
Example implementing services from multiple sources
Typically applications access data from different sources, displaying the results of the data association in an
application. This example shows how to associate data from the following three tables in an employees database:
• Departments
Each record contains the following fields: department number and department name.
• Dept_emp
Each record contains the following fields: emp_no, dept_no, from_date, to_date
• Employees
Each record contains the following fields: emp_no, birth_date, first_name, last_name, gender, hire_date
The sample application has two DataGrids, one for Departments and one for Employees.
The Departments lists all the departments. When you select a department, the Employees DataGrid lists all the
employees in that department.
When you select an employee in the Employees DataGrid, a form is populated, allowing you to update the employee
record.
Create the services
For this example, create a single service. The service contains the following operations:
• getAllDepartments()
• getEmployeesByDept()
•
getEmployeeByID()
•
updateEmployee()
EmployeeService (PHP)
EmployeeService.php implements a service that contains a single function. GetEmployeesByID() accepts the
department ID as an argument, returning all the employees in the given department. The function also returns the
dates an employee started and left the department. GetEmployeesByDept() executes the following SQL query:
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SELECT
employees.emp_no,
employees.birth_date,
employees.first_name,
employees.last_name,
employees.gender,
employees.hire_date,
dept_emp.from_date,
dept_emp.to_date
FROM employees, dept_emp
WHERE dept_emp.emp_no = employees.emp_no and
dept_emp.dept_no = departments.dept_no
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. Before deploying this service, be sure to increase security and restrict access appropriately. For information
on writing secure services, see “Deploying applications that access data services” on page 39.
<?php
/**
* EmployeeService.php
*
* This sample service contains functions that illustrate typical service operations.
* Use these functions as a starting point for creating your own service implementation.
*
* This code is for prototyping only.
*
* Authenticate the user before allowing them to call these methods.
*/
class EmployeeService {
var
var
var
var
var
var
$username = "admin2";
$password = "Cosmo49";
$server = "localhost";
$port = "3306";
$databasename = "employees";
$tablename = "employees";
var $connection;
/**
* The constructor initializes the connection to database. Everytime a request is
* received by Zend AMF, an instance of the service class is created and then the
* requested method is called.
*/
public function __construct() {
$this->connection = mysqli_connect(
$this->server,
$this->username,
$this->password,
$this->databasename,
$this->port
);
$this->throwExceptionOnError($this->connection);
}
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/**
* Returns all the rows from the table.
*
* Add authroization or any logical checks for secure access to your data
*
* @return array
*/
public function getAllDepartments() {
$stmt = mysqli_prepare($this->connection, "SELECT * FROM departments");
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
$rows = array();
mysqli_stmt_bind_result($stmt, $row->dept_no, $row->dept_name);
while (mysqli_stmt_fetch($stmt)) {
$rows[] = $row;
$row = new stdClass();
mysqli_stmt_bind_result($stmt, $row->dept_no, $row->dept_name);
}
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
return $rows;
}
public function getEmployeesByDept($deptId) {
$stmt = mysqli_prepare($this->connection, "select employees.emp_no,
employees.first_name,
employees.last_name,
employees.gender,
dept_emp.dept_no
from employees, dept_emp
where dept_emp.emp_no = employees.emp_no
and dept_emp.dept_no = ?
limit 0,30;");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 's', $deptId);
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
$rows = array();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->first_name,
$row->last_name, $row->gender, $row->dept_no);
while (mysqli_stmt_fetch($stmt)) {
$rows[] = $row;
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$row = new stdClass();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->first_name,
$row->last_name, $row->gender, $row->dept_no);
}
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
return $rows;
}
/**
* Returns the item corresponding to the value specified for the primary key.
*
* Add authroization or any logical checks for secure access to your data
*
*
* @return stdClass
*/
public function getEmployeesByID($itemID) {
$stmt = mysqli_prepare($this->connection, "SELECT * FROM employees
where emp_no=?");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'i', $itemID);
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
mysqli_stmt_bind_result($stmt, $row->emp_no, $row->birth_date,
$row->first_name, $row->last_name,
$row->gender, $row->hire_date);
if(mysqli_stmt_fetch($stmt)) {
return $row;
} else {
return null;
}
}
/**
* Updates the passed item in the table.
*
* Add authroization or any logical checks for secure access to your data
*
* @param stdClass $item
* @return void
*/
public function updateEmployees($item) {
$stmt = mysqli_prepare($this->connection, "UPDATE employees
SET emp_no=?, birth_date=?, first_name=?,
last_name=?, gender=?, hire_date=?
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WHERE emp_no=?");
$this->throwExceptionOnError();
mysqli_bind_param($stmt, 'isssssi', $item->emp_no, $item->birth_date,
$item->first_name, $item->last_name, $item->gender,
$item->hire_date, $item->emp_no);
$this->throwExceptionOnError();
mysqli_stmt_execute($stmt);
$this->throwExceptionOnError();
mysqli_stmt_free_result($stmt);
mysqli_close($this->connection);
}
/**
* Utitity function to throw an exception if an error occurs
* while running a mysql command.
*/
private function throwExceptionOnError($link = null) {
if($link == null) {
$link = $this->connection;
}
if(mysqli_error($link)) {
$msg = mysqli_errno($link) . ": " . mysqli_error($link);
throw new Exception('MySQL Error - '. $msg);
}
}
}
>?>
EmployeeService (ColdFusion)
EmployeeService.cfc implements a service that contains a single function. GetEmployeesByID() accepts the
department ID as an argument, returning all the employees in the given department. The function also returns the
dates an employee started and left the department. GetEmployeesByDept() executes the following SQL query:
SELECT
employees.emp_no,
employees.birth_date,
employees.first_name,
employees.last_name,
employees.gender,
employees.hire_date,
dept_emp.from_date,
dept_emp.to_date
FROM employees, dept_emp
WHERE dept_emp.emp_no = employees.emp_no and dept_emp.dept_no = departments.dept_no
Important: Example services are for prototyping only. Use the example service only in a trusted development
environment. Before deploying this service, be sure to increase security and restrict access appropriately. For information
on writing secure ColdFusion services, see the ColdFusion documentation About User Security.
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<cfcomponent output="false">
<!--This sample service contains functions that illustrate typical service operations.
Use these functions as a starting point for creating your own service implementation.
This code is for prototyping only.
Authenticate the user before allowing them to call these methods. You can find more
information at http://www.adobe.com/go/cf9_usersecurity
--->
<cffunction name="getEmployeesByDept" output="false" access="remote"
<cfargument name="dept_no" type="string" required="true" />
returntype="any" >
<cfset var qItem="">
<cfquery name="qItem" datasource="employees">
SELECT employees.emp_no,
employees.birth_date,
employees.first_name,
employees.last_name,
employees.gender,
employees.hire_date,
dept_emp.from_date,
dept_emp.to_date
FROM employees, dept_emp
WHERE dept_emp.emp_no = employees.emp_no and
dept_emp.dept_no = <CFQUERYPARAM CFSQLTYPE="CF_SQL_VARCHAR"
VALUE="#ARGUMENTS.dept_no#">
</cfquery>
<cfreturn qItem>
</cffunction>
</cfcomponent>?>
Import the services into a server project.
1 In Flash Builder, create a Flex Project that is named Associations:
(PHP) When creating the project, specify PHP for the Application Server Type.
(PHP) After creating the project, Flash Builder creates an output folder in the folder that is the web root of your
PHP configuration. The default name for the PHP_Associations project is PHP_Associations-debug.
(ColdFusion) When creating the project, specify ColdFusion for the Application Server Type. Then specify
ColdFusion Flash Remoting.
2 (PHP) Within PHP_Associations-debug, create a folder named services. Copy EmployeeService.php into
the services folder.
3 (ColdFusion) Create a folder named Associations in the web root of your ColdFusion configuration. Copy
EmployeeService.chc into the Associations folder.
4 Import the EmployeeService into the project:
Make sure PHP_Associations is the active project in Flash Builder.
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Select Data > Connect to PHP. To specify the PHP Class, browse to the services folder and select
EmployeeService.php. Click Finish.
For more information, see “Connecting to PHP data services” on page 10.
5 Configure the return type for the operations in EmployeeService.
• DepartmentService
From the context menu for getAllDepartments(), select Configure Return Type.
Click Next to auto-detect the return type.
Specify Department for the custom return type. Click Finish.
• EmployeeService
For getEmployeesByDept(), select Configure Return Type.
Click Next to auto-detect the return type.
For the value of the parameter, specify d007. Click Next.
Specify Employee for the custom return type. Click Finish.
For more information, see “Configuring data types for data service operations” on page 25.
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Chapter 4: Accessing server-side data
Adobe® Flex® data access components use remote procedure calls to interact with server environments, such as PHP,
Adobe ColdFusion, and Microsoft ASP.NET. These components provide data to client applications built with the
Adobe Flex framework, and send data to back-end data sources. For an introduction to data access components, see
“Data access components” on page 4.
Using HTTPService components
You can use an HTTPService component with any kind of server-side technology, including PHP pages, ColdFusion
Pages, Javaserver Pages (JSPs), Java servlets, Ruby on Rails, and Microsoft ASP pages. Additionally, you use
HTTPService to access REST-based web services.
For API reference information about the HTTPService component, see mx.rpc.http.mxml.HTTPService.
Working with PHP and SQL data
You can use an HTTPService component with PHP and a SQL database management system to display the results of
a database query in an application. You can also use the component to insert, update, and delete data in a database.
You can call a PHP page with GET or POST to perform a database query. You can then format the query result data
in an XML structure and return the XML structure to the application in the HTTP response. When the result has been
returned to the application, you can display it in one or more user interface controls.
MXML code
The application in the following example calls a PHP page with the POST method. The PHP page queries a MySQL
database table called users. It formats the query results as XML and returns the XML to the application, where it is
bound to the dataProvider property of a DataGrid control and displayed in the DataGrid control. The application
also sends the user name and email address of new users to the PHP page, which performs an insert into the user
database table.
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<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600"
creationComplete="send_data()">
<fx:Declarations>
<s:HTTPService id="userRequest" url="http://myserver/myproj/request_post2.php"
useProxy="false" method="POST">
<mx:request xmlns="">
<username>{username.text}</username>
<emailaddress>{emailaddress.text}</emailaddress>
</mx:request>
</s:HTTPService>
</fx:Declarations>
<fx:Script>
<![CDATA[
private function send_data():void {
userRequest.send();
}
]]>
</fx:Script>
<mx:Form x="20" y="10" width="300">
<mx:FormItem>
<s:Label text="Username" />
<s:TextInput id="username"/>
</mx:FormItem>
<mx:FormItem>
<s:Label text="Email Address" />
<s:TextInput id="emailaddress"/>
</mx:FormItem>
<s:Button label="Submit" click="send_data()"/>
</mx:Form>
<mx:DataGrid id="dgUserRequest" x="20" y="160"
dataProvider="{userRequest.lastResult.users.user}">
<mx:columns>
<mx:DataGridColumn headerText="User ID" dataField="userid"/>
<mx:DataGridColumn headerText="User Name" dataField="username"/>
</mx:columns>
</mx:DataGrid>
<s:TextInput x="20" y="340" id="selectedemailaddress"
text="{dgUserRequest.selectedItem.emailaddress}"/>
</s:Application>
The HTTPService’s send() method makes the call to the PHP page. This call is made in the send_data() method in
the Script block of the MXML file.
The resultFormat property of the HTTPService component is set to object, so the data is sent back to the
application as a graph of ActionScript objects. This is the default value for the resultFormat property. Alternatively,
you can use a resultFormat of e4x to return data as an XMLList object on which you can perform ECMAScript for
XML (E4X) operations. Switching the resultFormat property to e4x requires the following minor changes to the
MXML code.
Note: If the result format is e4x, you do not include the root node of the XML structure in the dot notation when binding
to the DataGrid.
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The XML returned in this example contains no namespace information. For information about working with XML
that does contain namespaces, see “Handling results as XML with the e4x result format” on page 123.
...
<s:HTTPService id="userRequest" url="http://myserver/myproj/request_post2.php"
useProxy="false" method="POST" resultFormat="e4x">
...
<mx:DataGrid id="dgUserRequest" x="22" y="150"
dataProvider="{userRequest.lastResult.user}">
...
When using the e4x result format, you can optionally bind the lastResult property to an XMLListCollection object
and then bind that object to the DataGrid.dataProvider property, as the following code snippet shows:
<fx:Declarations>
...
<mx:XMLListCollection id="xc"
source="{userRequest.lastResult.user}"/>
...
</fx:Declarations>
...
<mx:DataGrid id="dgUserRequest" x="22" y="128" dataProvider="{xc}">
...
MySQL database script
The PHP code for this application uses a database table called users in a MySQL database called sample. The following
MySQL script creates the table:
CREATE TABLE `users` (
`userid` int(10) unsigned NOT NULL auto_increment,
`username` varchar(255) collate latin1_general_ci NOT NULL,
`emailaddress` varchar(255) collate latin1_general_ci NOT NULL,
PRIMARY KEY (`userid`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci AUTO_INCREMENT=3 ;
PHP code
This application calls the following PHP page. This PHP code performs SQL database inserts and queries, and returns
query results to the application in an XML structure.
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<?php
define(
define(
define(
define(
"DATABASE_SERVER", "servername" );
"DATABASE_USERNAME", "username" );
"DATABASE_PASSWORD", "password" );
"DATABASE_NAME", "sample" );
//connect to the database.
$mysql = mysql_connect(DATABASE_SERVER, DATABASE_USERNAME, DATABASE_PASSWORD);
mysql_select_db( DATABASE_NAME );
// Quote variable to make safe
function quote_smart($value)
{
// Stripslashes
if (get_magic_quotes_gpc()) {
$value = stripslashes($value);
}
// Quote if not integer
if (!is_numeric($value)) {
$value = "'" . mysql_real_escape_string($value) . "'";
}
return $value;
}
if( $_POST["emailaddress"] AND $_POST["username"])
{
//add the user
$Query = sprintf("INSERT INTO users VALUES ('', %s, %s)",
quote_smart($_POST['username']), quote_smart($_POST['emailaddress']));
$Result = mysql_query( $Query );
}
//return a list of all the users
$Query = "SELECT * from users";
$Result = mysql_query( $Query );
$Return = "<users>";
while ( $User = mysql_fetch_object( $Result ) )
{
$Return .= "<user><userid>".$User->userid."</userid><username>".
$User->username."</username><emailaddress>".
$User->emailaddress."</emailaddress></user>";
}
$Return .= "</users>";
mysql_free_result( $Result );
print ($Return)
?>
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Working with ColdFusion and SQL data
You can use an HTTPService component with a ColdFusion page and a SQL database management system to display
the results of a database query in an application. You can also use the component to insert, update, and delete data in
a database. You call a ColdFusion page with GET or POST to perform a database query. You then format the query
result data in an XML structure and return the XML structure to the application in the HTTP response. When the
result has been returned to the application, you display it in one or more user interface controls.
MXML code
The application in the following example calls a ColdFusion page with the POST method. The ColdFusion page
queries a MySQL database table called users. It formats the query results as XML and returns the XML to the
application, where it is bound to the dataProvider property of a DataGrid control and displayed in the DataGrid
control. The application also sends the user name and email address of new users to the ColdFusion page, which
performs an insert into the user database table.
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600"
creationComplete="userRequest.send()">
<fx:Declarations>
<s:HTTPService id="userRequest" url="http://server:8500/flexapp/returncfxml.cfm"
useProxy="false" method="POST">
<mx:request xmlns="">
<username>{username.text}</username>
<emailaddress>{emailaddress.text}</emailaddress>
</mx:request>
</s:HTTPService>
</fx:Declarations>
<mx:Form x="22" y="10" width="300">
<mx:FormItem>
<s:Label text="Username" />
<s:TextInput id="username"/>
</mx:FormItem>
<mx:FormItem>
<s:Label text="Email Address" />
<s:TextInput id="emailaddress"/>
</mx:FormItem>
<s:Button label="Submit" click="userRequest.send()"/>
</mx:Form>
<mx:DataGrid id="dgUserRequest" x="22" y="128"
dataProvider="{userRequest.lastResult.users.user}">
<mx:columns>
<mx:DataGridColumn headerText="User ID" dataField="userid"/>
<mx:DataGridColumn headerText="User Name" dataField="username"/>
</mx:columns>
</mx:DataGrid>
<s:TextInput x="22" y="300" id="selectedemailaddress"
text="{dgUserRequest.selectedItem.emailaddress}"/>
</s:Application>
The HTTPService’s send() method makes the call to the ColdFusion page. This call is made in the send_data()
method in the Script block of the MXML file.
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The resultFormat property of the HTTPService component is set to object, so the data is sent back to the
application as a graph of ActionScript objects. This is the default value for the resultFormat property. Alternatively,
you can use a result format of e4x to return data as an XMLList object on which you can perform ECMAScript for
XML (E4X) operations. Switching the resultFormat property to e4x requires the following minor changes to the
MXML code.
Note: If the result format is e4x, you do not include the root node of the XML structure in the dot notation when binding
to the DataGrid.
The XML returned in this example contains no namespace information. For information about working with XML
that does contain namespaces, see “Handling results as XML with the e4x result format” on page 123.
...
<s:HTTPService id="userRequest" url="http://myserver:8500/flexapp/returncfxml.cfm"
useProxy="false" method="POST" resultFormat="e4x">
...
<mx:DataGrid id="dgUserRequest" x="22" y="128"
dataProvider="{userRequest.lastResult.user}">
...
When using the e4x result format, you can optionally bind the lastResult property to an XMLListCollection object
and then bind that object to the DataGrid dataProvider property, as the following code snippet shows:
<fx:Declarations>
...
<mx:XMLListCollection id="xc"
source="{userRequest.lastResult.user}"/>
...
</fx:Declarations>
...
<mx:DataGrid id="dgUserRequest" x="22" y="128" dataProvider="{xc}">
...
SQL script
The ColdFusion code for this application uses a database table called users in a MySQL database called sample. The
following MySQL script creates the table:
CREATE TABLE `users` (
`userid` int(10) unsigned NOT NULL auto_increment,
`username` varchar(255) collate latin1_general_ci NOT NULL,
`emailaddress` varchar(255) collate latin1_general_ci NOT NULL,
PRIMARY KEY (`userid`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_general_ci AUTO_INCREMENT=3 ;
ColdFusion code
The application that is listed in the Working with ColdFusion and SQL data section calls the following ColdFusion
application, returncfxml.cfm. This ColdFusion code performs SQL database inserts and queries, and returns query
results to the application. The ColdFusion page uses the cfquery tag to insert data into the database and query the
database, and it uses the cfxml tag to format the query results in an XML structure.
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<!--- returncfxml.cfm --->
<cfprocessingdirective pageencoding = "utf-8" suppressWhiteSpace = "Yes">
<cfif isDefined("username") and isDefined("emailaddress") and username NEQ "">
<cfquery name="addempinfo" datasource="sample">
INSERT INTO users (username, emailaddress) VALUES (
<cfqueryparam value="#username#" cfsqltype="CF_SQL_VARCHAR" maxlength="255">,
<cfqueryparam value="#emailaddress#" cfsqltype="CF_SQL_VARCHAR" maxlength="255"> )
</cfquery>
</cfif>
<cfquery name="alluserinfo" datasource="sample">
SELECT userid, username, emailaddress FROM users
</cfquery>
<cfxml variable="userXML">
<users>
<cfloop query="alluserinfo">
<cfoutput>
<user>
<userid>#toString(userid)#</userid>
<username>#username#</username>
<emailaddress>#emailaddress#</emailaddress>
</user>
</cfoutput>
</cfloop>
</users>
</cfxml>
<cfoutput>#userXML#</cfoutput>
</cfprocessingdirective>
Working with Javaserver Pages
You can use a Flex HTTPService component with a JSP page and a SQL database management system to display the
results of a database query in an application. You can also use the component to insert, update, and delete data in a
database. You call a JSP page with GET or POST to perform a database query. You then format the query result data
in an XML structure and return the XML structure to the application in the HTTP response. When the result has been
returned to the application, you display it in one or more user interface controls.
MXML code
The application in the following example calls a JSP page that retrieves data from a SQL database. It formats database
query results as XML and returns the XML to the application, where it is bound to the dataProvider property of a
DataGrid control and displayed in the DataGrid control.
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<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<fx:Declarations>
<s:HTTPService id="srv" url="catalog.jsp"/>
</fx:Declarations>
<mx:DataGrid dataProvider="{srv.lastResult.catalog.product}"
width="100%" height="100%"/>
<s:Button label="Get Data" click="srv.send()"/>
</mx:Application>
The HTTPService’s send() method makes the call to the JSP page. This call is made in the click event of the Button
in the MXML file.
The resultFormat property of the HTTPService component is set to object, so the data is sent back to the
application as a graph of ActionScript objects. This is the default value for the resultFormat property. Alternatively,
you can use a result format of e4x to return data as an XMLList object on which you can perform ECMAScript for
XML (E4X) operations. Switching the resultFormat property to e4x requires the following minor changes to the
MXML code.
Note: If the result format is e4x, you do not include the root node of the XML structure in the dot notation when binding
to the DataGrid.
The XML returned in this example contains no namespace information. For information about working with XML
that does contain namespaces, see “Handling results as XML with the e4x result format” on page 123.
...
<s:HTTPService id="srv" url="catalog.jsp" resultFormat="e4x"/>
...
<mx:DataGrid dataProvider="{srv.lastResult.product}" width="100%" height="100%"/>
When using the e4x result format, you can optionally bind the lastResult property to an XMLListCollection object
and then bind that object to the DataGrid.dataProvider property:
<fx:Declarations>
...
<mx:XMLListCollection id="xc"
source="{userRequest.lastResult.user}"/>
...
</fx:Declarations>
...
<mx:DataGrid id="dgUserRequest" x="22" y="128" dataProvider="{xc}">
...
JSP code
The following example shows the JSP page used in this application. This JSP page does not call a database directly. It
gets its data from a Java class called ProductService, which in turn uses a Java class called Product to represent
individual products.
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<%@page import="flex.samples.product.ProductService,
flex.samples.product.Product,
java.util.List"%>
<?xml version="1.0" encoding="utf-8"?>
<catalog>
<%
ProductService srv = new ProductService();
List list = null;
list = srv.getProducts();
Product product;
for (int i=0; i<list.size(); i++)
{
product = (Product) list.get(i);
%>
<product productId="<%= product.getProductId()%>">
<name><%= product.getName() %></name>
<description><%= product.getDescription() %></description>
<price><%= product.getPrice() %></price>
<image><%= product.getImage() %></image>
<category><%= product.getCategory() %></category>
<qtyInStock><%= product.getQtyInStock() %></qtyInStock>
</product>
<%
}
%>
</catalog>
Calling HTTP services in ActionScript
The following example shows an HTTP service call in an ActionScript script block. Calling the useHTTPService()
method declares the service, sets the destination, sets up result and fault event listeners, and calls the service’s send()
method.
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<?xml version="1.0"?>
<!-- fds\rpc\HttpServiceInAS.mxml. Compiles -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" verticalGap="10">
<mx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.rpc.http.HTTPService;
import mx.rpc.events.ResultEvent;
import mx.rpc.events.FaultEvent;
private var service:HTTPService
public function useHttpService(parameters:Object):void {
service = new HTTPService();
service.url = "catalog.jsp";
service.method = "POST";
service.addEventListener("result", httpResult);
service.addEventListener("fault", httpFault);
service.send(parameters);
}
public function httpResult(event:ResultEvent):void {
var result:Object = event.result;
//Do something with the result.
}
public function httpFault(event:FaultEvent):void {
var faultstring:String = event.fault.faultString;
Alert.show(faultstring);
}
]]>
</mx:Script>
</mx:Application>
Using WebService components
Applications created with the Flex framework can interact with SOAP-based web services that define their interfaces
in a Web Services Description Language 1.1 (WSDL 1.1) document, which is available as a URL. WSDL is a standard
format for describing the messages that a web service understands, the format of its responses to those messages, the
protocols that the web service supports, and where to send messages. The Flex web service API generally supports
Simple Object Access Protocol (SOAP) 1.1, XML Schema 1.0 (versions 1999, 2000, and 2001), and WSDL 1.1 RPCencoded, RPC-literal, and document-literal (bare and wrapped style parameters). The two most common types of web
services use remote procedure call (RPC) encoded or document-literal SOAP bindings; the terms encoded and literal
indicate the type of WSDL-to-SOAP mapping that a service uses.
Flex supports web service requests and results that are formatted as SOAP messages. SOAP provides the definition of
the XML-based format that you can use for exchanging structured and typed information between a web service client,
such as an application built with Flex, and a web service.
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Adobe® Flash® Player operates within a security sandbox that limits what applications built with Flex and other
applications built with Flash can access over HTTP. Applications built with Flash are allowed HTTP access only to
resources on the same domain and by the same protocol from which they were served. This presents a problem for web
services, because they are typically accessed from remote locations. The proxy service, available in LiveCycle Data
Services and BlazeDS, intercepts requests to remote web services, redirects the requests, and then returns the responses
to the client.
If you are not using LiveCycle Data Services or BlazeDS, you can access web services in the same domain as your
application; or a crossdomain.xml (cross-domain policy) file that allows access from your application's domain must
be installed on the web server hosting the RPC service.
For API reference information about the WebService component, see mx.rpc.soap.mxml.WebService.
Sample WebService application
The following sample code is for an application that uses a WebService component to call web service operations.
MXML code
The application in the following example calls a web service that queries a SQL database table called users and returns
data to the application, where it is bound to the dataProvider property of a DataGrid control and displayed in the
DataGrid control. The application also sends the user name and e-mail address of new users to the web service, which
performs an insert into the user database table. The back-end implementation of the web service is a ColdFusion
component; the same ColdFusion component is accessed as a remote object in “Using RemoteObject components” on
page 97.
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<fx:Declarations>
<s:WebService
id="userRequest"
wsdl="http://localhost:8500/flexapp/returnusers.cfc?wsdl">
<mx:operation name="returnRecords" resultFormat="object"
fault="mx.controls.Alert.show(event.fault.faultString)"
result="remotingCFCHandler(event)"/>
<mx:operation name="insertRecord" result="insertCFCHandler()"
fault="mx.controls.Alert.show(event.fault.faultString)"/>
</s:WebService>
</fx:Declarations>
<fx:Script>
<![CDATA[
import mx.rpc.events.ResultEvent;
private function remotingCFCHandler(e:ResultEvent):void
{
dgUserRequest.dataProvider = e.result;
}
private function insertCFCHandler():void
{
userRequest.returnRecords();
}
private function clickHandler():void
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{
userRequest.insertRecord(username.text, emailaddress.text);
}
]]>
</fx:Script>
<mx:Form x="22" y="10" width="300">
<mx:FormItem>
<s:Label text="Username" />
<s:TextInput id="username"/>
</mx:FormItem>
<mx:FormItem>
<s:Label text="Email Address" />
<s:TextInput id="emailaddress"/>
</mx:FormItem>
<s:Button label="Submit" click="clickHandler()"/>
</mx:Form>
<mx:DataGrid id="dgUserRequest" x="22" y="160">
<mx:columns>
<mx:DataGridColumn headerText="User ID" dataField="USERID"/>
<mx:DataGridColumn headerText="User Name" dataField="USERNAME"/>
</mx:columns>
</mx:DataGrid>
<s:TextInput x="22" y="320" id="selectedemailaddress"
text="{dgUserRequest.selectedItem.emailaddress}"/>
</s:Application>
WSDL document
The following example shows the WSDL document that defines the API of the web service:
<?xml version="1.0" encoding="UTF-8"?>
<wsdl:definitions targetNamespace="http://flexapp"
xmlns:apachesoap="http://xml.apache.org/xml-soap"
xmlns:impl="http://flexapp" xmlns:intf="http://flexapp"
xmlns:soapenc="http://schemas.xmlsoap.org/soap/encoding/"
xmlns:tns1="http://rpc.xml.coldfusion"
xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/"
xmlns:wsdlsoap="http://schemas.xmlsoap.org/wsdl/soap/"
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<!--WSDL created by ColdFusion version 8,0,0,171651-->
<wsdl:types>
<schema targetNamespace="http://rpc.xml.coldfusion"
xmlns="http://www.w3.org/2001/XMLSchema">
<import namespace="http://flexapp"/>
<import namespace="http://schemas.xmlsoap.org/soap/encoding/"/>
<complexType name="CFCInvocationException">
<sequence/>
</complexType>
<complexType name="QueryBean">
<sequence>
<element name="columnList" nillable="true" type="impl:ArrayOf_xsd_string"/>
<element name="data" nillable="true" type="impl:ArrayOfArrayOf_xsd_anyType"/>
</sequence>
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</complexType>
</schema>
<schema targetNamespace="http://flexapp" xmlns="http://www.w3.org/2001/XMLSchema">
<import namespace="http://rpc.xml.coldfusion"/>
<import namespace="http://schemas.xmlsoap.org/soap/encoding/"/>
<complexType name="ArrayOf_xsd_string">
<complexContent>
<restriction base="soapenc:Array">
<attribute ref="soapenc:arrayType" wsdl:arrayType="xsd:string[]"/>
</restriction>
</complexContent>
</complexType>
<complexType name="ArrayOfArrayOf_xsd_anyType">
<complexContent>
<restriction base="soapenc:Array">
<attribute ref="soapenc:arrayType" wsdl:arrayType="xsd:anyType[][]"/>
</restriction>
</complexContent>
</complexType>
</schema>
</wsdl:types>
<wsdl:message name="CFCInvocationException">
<wsdl:part name="fault" type="tns1:CFCInvocationException"/>
</wsdl:message>
<wsdl:message name="returnRecordsRequest">
</wsdl:message>
<wsdl:message name="insertRecordResponse">
</wsdl:message>
<wsdl:message name="returnRecordsResponse">
<wsdl:part name="returnRecordsReturn" type="tns1:QueryBean"/>
</wsdl:message>
<wsdl:message name="insertRecordRequest">
<wsdl:part name="username" type="xsd:string"/>
<wsdl:part name="emailaddress" type="xsd:string"/>
</wsdl:message>
<wsdl:portType name="returncfxml">
<wsdl:operation name="insertRecord" parameterOrder="username emailaddress">
<wsdl:input message="impl:insertRecordRequest" name="insertRecordRequest"/>
<wsdl:output message="impl:insertRecordResponse" name="insertRecordResponse"/>
<wsdl:fault message="impl:CFCInvocationException" name="CFCInvocationException"/>
</wsdl:operation>
<wsdl:operation name="returnRecords">
<wsdl:input message="impl:returnRecordsRequest" name="returnRecordsRequest"/>
<wsdl:output message="impl:returnRecordsResponse" name="returnRecordsResponse"/>
<wsdl:fault message="impl:CFCInvocationException" name="CFCInvocationException"/>
</wsdl:operation>
</wsdl:portType>
<wsdl:binding name="returncfxml.cfcSoapBinding" type="impl:returncfxml">
<wsdlsoap:binding style="rpc" transport="http://schemas.xmlsoap.org/soap/http"/>
<wsdl:operation name="insertRecord">
<wsdlsoap:operation soapAction=""/>
<wsdl:input name="insertRecordRequest">
<wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
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namespace="http://flexapp" use="encoded"/>
</wsdl:input>
<wsdl:output name="insertRecordResponse">
<wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
namespace="http://flexapp" use="encoded"/>
</wsdl:output>
<wsdl:fault name="CFCInvocationException">
<wsdlsoap:fault encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
name="CFCInvocationException" namespace="http://flexapp" use="encoded"/>
</wsdl:fault>
</wsdl:operation>
<wsdl:operation name="returnRecords">
<wsdlsoap:operation soapAction=""/>
<wsdl:input name="returnRecordsRequest">
<wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
namespace="http://flexapp" use="encoded"/>
</wsdl:input>
<wsdl:output name="returnRecordsResponse">
<wsdlsoap:body encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
namespace="http://flexapp" use="encoded"/>
</wsdl:output>
<wsdl:fault name="CFCInvocationException">
<wsdlsoap:fault encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"
name="CFCInvocationException" namespace="http://flexapp" use="encoded"/>
</wsdl:fault>
</wsdl:operation>
</wsdl:binding>
<wsdl:service name="returncfxmlService">
<wsdl:port binding="impl:returncfxml.cfcSoapBinding" name="returncfxml.cfc">
<wsdlsoap:address location="http://localhost:8500/flexapp/returnusers.cfc"/>
</wsdl:port>
</wsdl:service>
</wsdl:definitions>
Calling web services in ActionScript
The following example shows a web service call in an ActionScript script block. Calling the useWebService() method
declares the service, sets the destination, fetches the WSDL document, and calls the echoArgs() method of the service.
Note: When you declare a WebService component in ActionScript, call the WebService.loadWSDL() method.
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<?xml version="1.0"?>
<!-- fds\rpc\WebServiceInAS.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
<mx:Script>
<![CDATA[
import mx.rpc.soap.WebService;
import mx.rpc.events.ResultEvent;
import mx.rpc.events.FaultEvent;
private var ws:WebService;
public function useWebService(intArg:int, strArg:String):void {
ws = new WebService();
ws.wsdl="http://myserver:8500/flexapp/app1.cfc?wsdl";
ws.echoArgs.addEventListener("result", echoResultHandler);
ws.addEventListener("fault", faultHandler);
ws.loadWSDL();
ws.echoArgs(intArg, strArg);
}
public function echoResultHandler(event:ResultEvent):void {
var retStr:String = event.result.echoStr;
var retInt:int = event.result.echoInt;
//Do something.
}
public function faultHandler(event:FaultEvent):void {
//deal with event.fault.faultString, etc
}
]]>
</mx:Script>
</mx:Application>
Reserved Operation names
WebService operations are accessible by simply naming them after a service variable. However, naming conflicts can
occur if an operation name happens to match a defined method on the service. You can use the following method in
ActionScript on a WebService component to return the operation of the given name:
public function getOperation(name:String):Operation
Reading WSDL documents
You can view a WSDL document in a web browser, a simple text editor, an XML editor, or a development environment
such as Adobe Dreamweaver, which contains a built-in utility for displaying WSDL documents in an easy-to-read
format.
A WSDL document contains the tags described in the following table.
Tag
Description
<binding>
Specifies the protocol that clients, such as applications built with Flex, use to communicate with a web service. Bindings
exist for SOAP, HTTP GET, HTTP POST, and MIME. Flex supports the SOAP binding only.
<fault>
Specifies an error value that is returned as a result of a problem processing a message.
<input>
Specifies a message that a client, such as an application built with Flex, sends to a web service.
<message>
Defines the data that a WebService operation transfers.
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Tag
Description
<operation> Defines a combination of <input>, <output>, and <fault> tags.
<output>
Specifies a message that the web service sends to a web service client, such as an application built with Flex.
<port>
Specifies a web service endpoint, which specifies an association between a binding and a network address.
<portType>
Defines one or more operations that a web service provides.
<service>
Defines a collection of <port> tags. Each service maps to one <portType> tag and specifies different ways to access
the operations in that <portType> tag.
<types>
Defines data types that a web service's messages use.
RPC-oriented operations and document-oriented operations
A WSDL file can specify either RPC-oriented or document-oriented (document-literal) operations. Flex supports both
operation styles.
When calling an RPC-oriented operation, an application sends a SOAP message that specifies an operation and its
parameters. When calling a document-oriented operation, an application sends a SOAP message that contains an
XML document.
In a WSDL document, each <port> tag has a binding property that specifies the name of a particular
<soap:binding> tag, as the following example shows:
<binding name="InstantMessageAlertSoap" type="s0:InstantMessageAlertSoap">
<soap:binding transport="http://schemas.xmlsoap.org/soap/http"
style="document"/>
The style property of the associated <soap:binding> tag determines the operation style. In this example, the style
is document.
Any operation in a service can specify the same style or override the style that is specified for the port associated with
the service, as the following example shows:
<operation name="SendMSN">
<soap:operation soapAction="http://www.bindingpoint.com/ws/imalert/
SendMSN"style="document"/>
Stateful web services
Flex uses Java server sessions to maintain the state of web service endpoints that use cookies to store session
information. This feature acts as an intermediary between applications and web services. It adds an endpoint's identity
to whatever the endpoint passes to an application. If the endpoint sends session information, the application receives
it. This feature requires no configuration, and it is not supported for destinations that use the RTMP channel when
using the proxy service.
Working with SOAP headers
A SOAP header is an optional tag in a SOAP envelope that usually contains application-specific information, such as
authentication information.
Adding SOAP headers to web service requests
Some web services require that you pass along a SOAP header when you call an operation.
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You can add a SOAP header to all web service operations or individual operations by calling a WebService or
Operation object's addHeader() method or addSimpleHeader() method in an event listener function.
When you use the addHeader() method, you first must create SOAPHeader and QName objects separately. The
addHeader() method has the following signature:
addHeader(header:mx.rpc.soap.SOAPHeader):void
To create a SOAPHeader object, use the following constructor:
SOAPHeader(qname:QName, content:Object)
To create the QName object in the first parameter of the SOAPHeader() method, use the following constructor:
QName(uri:String, localName:String)
The content parameter of the SOAPHeader() constructor is a set of name-value pairs based on the following format:
{name1:value1, name2:value2}
The addSimpleHeader() method is a shortcut for a single name-value SOAP header. When you use the
addSimpleHeader() method, you create SOAPHeader and QName objects in parameters of the method. The
addSimpleHeader() method has the following signature:
addSimpleHeader(qnameLocal:String, qnameNamespace:String, headerName:String,
headerValue:Object):void
The addSimpleHeader() method takes the following parameters:
•
qnameLocal is the local name for the header QName.
•
qnameNamespace is the namespace for the header QName.
•
headerName is the name of the header.
•
headerValue is the value of the header. This can be a string if it is a simple value, an object that will undergo basic
XML encoding, or XML if you want to specify the header XML yourself.
The code in the following example shows how to use the addHeader() method and the addSimpleHeader()
method to add a SOAP header. The methods are called in an event listener function called headers, and the event
listener is assigned in the load property of an <mx:WebService> tag:
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<?xml version="1.0"?>
<!-- fds\rpc\WebServiceAddHeader.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" height="600">
<mx:WebService id="ws" wsdl="http://myserver:8500/flexapp/app1.cfc?wsdl"
load="headers();"/>
<mx:Script>
<![CDATA[
import mx.rpc.soap.SOAPHeader;
private var header1:SOAPHeader;
private var header2:SOAPHeader;
public function headers():void {
// Create QName and SOAPHeader objects.
var q1:QName=new QName("http://soapinterop.org/xsd", "Header1");
header1=new SOAPHeader(q1, {string:"bologna",int:"123"});
header2=new SOAPHeader(q1, {string:"salami",int:"321"});
// Add the header1 SOAP Header to all web service requests.
ws.addHeader(header1);
// Add the header2 SOAP Header to the getSomething operation.
ws.getSomething.addHeader(header2);
// Within the addSimpleHeader method,
// which adds a SOAP header to web
//service requests, create SOAPHeader and QName objects.
ws.addSimpleHeader
("header3", "http://soapinterop.org/xsd", "foo","bar");
}
]]>
</mx:Script>
</mx:Application>
Clearing SOAP headers
You use the WebService or operation object's clearHeaders() method to remove SOAP headers that you added to
the object, as the following example shows for a WebService object. You must call clearHeaders() at the level
(WebService or operation) where the header was added.
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<?xml version="1.0"?>
<!-- fds\rpc\WebServiceClearHeader.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" height="600" >
<!-- The value of the destination property is for demonstration only and is not a real
destination. -->
<mx:WebService id="ws" wsdl="http://myserver:8500/flexapp/app1.cfc?wsdl"
load="headers();"/>
<mx:Script>
<![CDATA[
import mx.rpc.*;
import mx.rpc.soap.SOAPHeader;
private function headers():void {
// Create QName and SOAPHeader objects.
var q1:QName=new QName("Header1", "http://soapinterop.org/xsd");
var header1:SOAPHeader=new SOAPHeader(q1, {string:"bologna",int:"123"});
var header2:SOAPHeader=new SOAPHeader(q1, {string:"salami",int:"321"});
// Add the header1 SOAP Header to all web service request.
ws.addHeader(header1);
// Add the header2 SOAP Header to the getSomething operation.
ws.getSomething.addHeader(header2);
// Within the addSimpleHeader method, which adds a SOAP header to all
// web service requests, create SOAPHeader and QName objects.
ws.addSimpleHeader("header3","http://soapinterop.org/xsd", "foo", "bar");
}
// Clear SOAP headers added at the WebService and Operation levels.
private function clear():void {
ws.clearHeaders();
ws.getSomething.clearHeaders();
}
]]>
</mx:Script>
<mx:HBox>
<mx:Button label="Clear headers and run again" click="clear();"/>
</mx:HBox>
</mx:Application>
Redirecting a web service to a different URL
Some web services require that you change to a different endpoint URL after you process the WSDL and make an
initial call to the web service. For example, suppose that you want to use a web service that requires you to pass security
credentials. When you call the web service to send login credentials, it accepts the credentials and returns the actual
endpoint URL that is required to use the service's business operations. Before calling the business operations, you must
change the endpointURI property of your WebService component.
The following example shows a result event listener that stores the endpoint URL that a web service returns in a
variable, and then passes that variable into a function to change the endpoint URL for subsequent requests:
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...
public function onLoginResult(event:ResultEvent):void {
//Extract the new service endpoint from the login result.
var newServiceURL = event.result.serverUrl;
// Redirect all service operations to the URL received in the login result.
serviceName.endpointURI=newServiceURL;
}
...
A web service that requires you to pass security credentials might also return an identifier that you must attach in a
SOAP header for subsequent requests. For more information, see “Working with SOAP headers” on page 86.
Serializing web service data
Encoding ActionScript data
The following table shows the encoding mappings from ActionScript 3.0 types to XML schema complex types.
XML schema definition
Supported ActionScript 3.0 types
Notes
Object
If input value is null, encoded output is set with the
xsi:nil attribute.
Object
Input value is ignored and fixed value is used instead.
Object
If input value is null, this default value is used instead.
Object
Input value is ignored and omitted from encoded output.
Object
Input value is processed as a single entity. If the associated
type is a SOAP-encoded array, then arrays and
mx.collection.IList implementations pass through
intact to be special cased by the SOAP encoder for that
type.
Object
Input value should be iterable (such as an array or
mx.collections.IList implementation), although
noniterable values are wrapped before processing.
Individual items are encoded as separate entities
according to the definition.
Object
If input value is undefined or null, encoded output is
omitted.
Top-level elements
xsd:element
nillable == true
xsd:element
fixed != null
xsd:element
default != null
Local elements
xsd:element
maxOccurs == 0
xsd:element
maxOccurs == 1
xsd:element
maxOccurs > 1
xsd:element
minOccurs == 0
The following table shows the encoding mappings from ActionScript 3.0 types to XML schema built-in types.
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XML schema type
Supported ActionScript 3.0 types
Notes
xsd:anyType
Object
Boolean -> xsd:boolean
ByteArray -> xsd:base64Binary
xsd:anySimpleType
Date -> xsd:dateTime
int -> xsd:int
Number -> xsd:double
String -> xsd:string
uint -> xsd:unsignedInt
xsd:base64Binary
flash.utils.ByteArray
mx.utils.Base64Encoder is used (without line
wrapping).
Boolean
Always encoded as true or false.
Number
Number == 1 then true, otherwise false.
Object
Object.toString() == "true" or "1" then true,
otherwise false.
xsd:byte
Number
String first converted to Number.
xsd:unsignedByte
String
xsd:date
Date
Date UTC accessor methods are used.
Number
Number used to set Date.time.
String
String assumed to be preformatted and encoded as is.
Date
Date UTC accessor methods are used.
Number
Number used to set Date.time.
String
String assumed to be preformatted and encoded as is.
Number
Number.toString() is used. Infinity, -Infinity, and
xsd:boolean
xsd:dateTime
xsd:decimal
String
NaN are invalid for this type.
String first converted to Number.
Number
Limited to range of Number.
String
String first converted to Number.
xsd:duration
Object
Object.toString() is called.
xsd:float
Number
Limited to range of Number.
String
String first converted to Number.
Date
Date.getUTCDate() is used.
Number
Number used directly for day.
String
String parsed as Number for day.
Date
Date.getUTCMonth() is used.
Number
Number used directly for month.
String
String parsed as Number for month.
Date
Date.getUTCMonth() and Date.getUTCDate()
xsd:double
xsd:gDay
xsd:gMonth
xsd:gMonthDay
String
are used.
String parsed for month and day portions.
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XML schema type
Supported ActionScript 3.0 types
Notes
xsd:gYear
Date
Date.getUTCFullYear() is used.
Number
Number used directly for year.
String
String parsed as Number for year.
Date
Date.getUTCFullYear() and
Date.getUTCMonth() are used.
xsd:gYearMonth
String
String parsed for year and month portions.
xsd:hexBinary
flash.utils.ByteArray
mx.utils.HexEncoder is used.
xsd:integer
Number
Limited to range of Number.
and derivatives:
String
String first converted to Number.
xsd:int
Number
String first converted to Number.
xsd:unsignedInt
String
xsd:long
Number
xsd:unsignedLong
String
xsd:short
Number
xsd:unsignedShort
String
xsd:string
Object
Object.toString() is invoked.
Date
Date UTC accessor methods are used.
Number
Number used to set Date.time.
String
String assumed to be preformatted and encoded as is.
null
If the corresponding XML schema element definition has
minOccurs > 0, a null value is encoded by using xsi:nil;
otherwise the element is omitted entirely.
xsd:negativeInteger
xsd:nonNegativeInteger
xsd:positiveInteger
xsd:nonPositiveInteger
String first converted to Number.
String first converted to Number.
and derivatives:
xsd:ID
xsd:IDREF
xsd:IDREFS
xsd:ENTITY
xsd:ENTITIES xsd:language
xsd:Name
xsd:NCName
xsd:NMTOKEN
xsd:NMTOKENS
xsd:normalizedString
xsd:token
xsd:time
xsi:nil
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The following table shows the mapping from ActionScript 3.0 types to SOAP-encoded types.
SOAPENC type
Supported ActionScript 3.0 types
Notes
soapenc:Array
Array
SOAP-encoded arrays are special cased and are supported only with
RPC-encoded style web services.
mx.collections.IList
soapenc:base64
flash.utils.ByteArray
Encoded in the same manner as xsd:base64Binary.
soapenc:*
Object
Any other SOAP-encoded type is processed as if it were in the XSD
namespace based on the localName of the type's QName.
Decoding XML schema and SOAP to ActionScript 3.0
The following table shows the decoding mappings from XML schema built-in types to ActionScript 3.0 types.
XML schema type
Decoded ActionScript 3.0 types
Notes
xsd:anyType
String
If content is empty -> xsd:string.
xsd:anySimpleType
Boolean
If content cast to Number and value is NaN; or
Number
if content starts with "0" or "-0", or
it content ends with "E":
then, if content is "true" or "false" -> xsd:boolean
otherwise -> xsd:string.
Otherwise content is a valid Number and thus ->
xsd:double.
xsd:base64Binary
flash.utils.ByteArray
mx.utils.Base64Decoder is used.
xsd:boolean
Boolean
If content is "true" or "1" then true, otherwise false.
xsd:date
Date
If no time zone information is present, local time is
assumed.
xsd:dateTime
Date
If no time zone information is present, local time is
assumed.
xsd:decimal
Number
Content is created via Number(content) and is thus
limited to the range of Number.
xsd:double
Number
Content is created via Number(content) and is thus
limited to the range of Number.
xsd:duration
String
Content is returned with whitespace collapsed.
xsd:float
Number
Content is converted through Number(content) and is
thus limited to the range of Number.
xsd:gDay
uint
Content is converted through uint(content).
xsd:gMonth
uint
Content is converted through uint(content).
xsd:gMonthDay
String
Content is returned with whitespace collapsed.
xsd:gYear
uint
Content is converted through uint(content).
xsd:gYearMonth
String
Content is returned with whitespace collapsed.
xsd:hexBinary
flash.utils.ByteArray
mx.utils.HexDecoder is used.
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XML schema type
Decoded ActionScript 3.0 types
Notes
xsd:integer
Number
Content is decoded via parseInt().
String
The raw content is simply returned as a string.
xsd:time
Date
If no time zone information is present, local time is
assumed.
xsi:nil
null
and derivatives:
xsd:byte
xsd:int
xsd:long
xsd:negativeInteger
xsd:nonNegativeInteger
xsd:nonPositiveInteger
xsd:positiveInteger
xsd:short
xsd:unsignedByte
xsd:unsignedInt
xsd:unsignedLong
xsd:unsignedShort
xsd:string
and derivatives:
xsd:ID
xsd:IDREF
xsd:IDREFS
xsd:ENTITY
xsd:ENTITIES xsd:language
xsd:Name
xsd:NCName
xsd:NMTOKEN
xsd:NMTOKENS
xsd:normalizedString
xsd:token
The following table shows the decoding mappings from SOAP-encoded types to ActionScript 3.0 types.
SOAPENC type
Decoded ActionScript type
Notes
soapenc:Array
Array
SOAP-encoded arrays are special cased. If
makeObjectsBindable is true, the result is wrapped in an
ArrayCollection; otherwise a simple array is returned.
mx.collections.ArrayCollection
soapenc:base64
flash.utils.ByteArray
Decoded in the same manner as xsd:base64Binary.
soapenc:*
Object
Any other SOAP-encoded type is processed as if it were in the XSD
namespace based on the localName of the type's QName.
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The following table shows the decoding mappings from custom data types to ActionScript 3.0 data types.
Custom type
Decoded ActionScript 3.0 type
Notes
Apache Map
Object
SOAP representation of
java.util.Map. Keys
http://xml.apache.org/xml-soap:Map
Apache Rowset
must be representable as
strings.
Array of objects
http://xml.apache.org/xml-soap:Rowset
ColdFusion QueryBean
Array of objects
http://rpc.xml.coldfusion:QueryBean
mx.collections.ArrayCollection of objects
If makeObjectsBindable
is true, the resulting array is
wrapped in an
ArrayCollection.
XML Schema element support
The following XML schema structures or structure attributes are only partially implemented in Flex 4:
<choice>
<all>
<union
The following XML Schema structures or structure attributes are ignored and are not supported in Flex 4:
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<attribute use="required"/>
<element
substitutionGroup="..."
unique="..."
key="..."
keyref="..."
field="..."
selector="..."/>
<simpleType>
<restriction>
<minExclusive>
<minInclusive>
<maxExclusiv>
<maxInclusive>
<totalDigits>
<fractionDigits>
<length>
<minLength>
<maxLength>
<enumeration>
<whiteSpace>
<pattern>
</restriction>
</simpleType>
<complexType
final="..."
block="..."
mixed="..."
abstract="..."/>
<any
processContents="..."/>
<annotation>
Customizing web service type mapping
When consuming data from a web service invocation, Flex usually creates untyped anonymous ActionScript objects
that mimic the XML structure in the body of the SOAP message. If you want Flex to create an instance of a specific
class, you can use an mx.rpc.xml.SchemaTypeRegistry object and register a QName object with a corresponding
ActionScript class.
For example, suppose you have the following class definition in a file named User.as:
package
{
public class User
{
public function User() {}
public var firstName:String;
public var lastName:String;
}
}
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Next, you want to invoke a getUser operation on a web service that returns the following XML:
<tns:getUserResponse xmlns:tns="http://example.uri">
<tns:firstName>Ivan</tns:firstName>
<tns:lastName>Petrov</tns:lastName>
</tns:getUserResponse>
Make sure you get an instance of your User class instead of a generic Object when you invoke the getUser operation,
you need the following ActionScript code inside a method in your application:
SchemaTypeRegistry.getInstance().registerClass(new QName("http://example.uri",
"getUserResponse"), User);
SchemaTypeRegistry.getInstance() is a static method that returns the default instance of the type registry. In
most cases, that is all you need. However, this registers a given QName with the same ActionScript class across all web
service operations in your application. If you want to register different classes for different operations, you need the
following code in a method in your application:
var qn:QName = new QName("http://the.same", "qname");
var typeReg1:SchemaTypeRegistry = new SchemaTypeRegistry();
var typeReg2:SchemaTypeRegistry = new SchemaTypeRegistry();
typeReg1.registerClass(qn, someClass);
myWS.someOperation.decoder.typeRegistry = typeReg1;
typeReg2.registerClass(qn, anotherClass);
myWS.anotherOperation.decoder.typeRegistry = typeReg2;
Using custom web service serialization
There are two approaches to take full control over how ActionScript objects are serialized into XML and how XML
response messages are deserialized. The recommended one is to work directly with E4X.
If you pass an instance of XML as the only parameter to a web service operation, it is passed on untouched as the child
of the <SOAP:Body> node in the serialized request. Use this strategy when you need full control over the SOAP
message. Similarly, when deserializing a web service response, you can set the operation’s resultFormat property to
e4x. This returns an XMLList object with the children of the <SOAP:Body> node in the response message. From there,
you can implement the necessary custom logic to create the appropriate ActionScript objects.
The second and more tedious approach is to provide your own implementations of mx.rpc.soap.ISOAPDecoder and
mx.rpc.soap.ISOAPEncoder. For example, if you have written a class called MyDecoder that implements
ISOAPDecoder, you can have the following in a method in your application:
myWS.someOperation.decoder = new MyDecoder();
When you invoke someOperation, Flex calls the decodeResponse() method of the MyDecoder class. From that
point on it is up to the custom implementation to handle the full SOAP message and produce the expected
ActionScript objects.
Using RemoteObject components
You can use a Flex RemoteObject component to call methods on a ColdFusion component or Java class.
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You can also use RemoteObject components with PHP and .NET objects with third-party software, such as the open
source projects AMFPHP and SabreAMF, and Midnight Coders WebORB. For more information, see the following
websites:
• Zend Framework http://framework.zend.com/
• AMFPHP http://amfphp.sourceforge.net/
• SabreAMF http://www.osflash.org/sabreamf
• Midnight Coders WebORB http://www.themidnightcoders.com/
RemoteObject components use the AMF protocol to send and receive data, while WebService and HTTPService
components use the HTTP protocol. AMF is significantly faster than HTTP, however server-side coding and
configuration is typically more complex.
Flash Builder for PHP is a development tool created in partnership with Zend Technologies that includes an integrated
copy of Zend Studio. For more information, see the Adobe website.
As with HTTPService and WebService components, you can use a RemoteObject component to display the result of a
database query in an application. You can also use the component to insert, update, and delete data in a database.
When the result of the query has been returned to the application, you can display it in one or more user interface
controls.
For API reference information about the RemoteObject component, see mx.rpc.remoting.mxml.RemoteObject.
Sample RemoteObject application
MXML code
The application in the following example uses a RemoteObject component to call a ColdFusion component. The
ColdFusion component queries a MySQL database table called users. It returns the query result to the application
where it is bound to the dataProvider property of a DataGrid control and displayed in the DataGrid control. The
application also sends the user name and e-mail address of new users to the ColdFusion component, which performs
an insert into the user database table.
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600">
<fx:Declarations>
<mx:RemoteObject
id="userRequest"
destination="ColdFusion"
source="flexapp.returnusers">
<mx:method name="returnRecords" result="returnHandler(event)"
fault="mx.controls.Alert.show(event.fault.faultString)"/>
<mx:method name="insertRecord" result="insertHandler()"
fault="mx.controls.Alert.show(event.fault.faultString)"/>
</mx:RemoteObject>
</fx:Declarations>
<fx:Script>
<![CDATA[
import mx.rpc.events.ResultEvent;
private function returnHandler(e:ResultEvent):void
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{
dgUserRequest.dataProvider = e.result;
}
private function insertHandler():void
{
userRequest.returnRecords();
}
private function clickHandler():void
{
userRequest.insertRecord(username.text, emailaddress.text);
}
]]>
</fx:Script>
<mx:Form x="22" y="10" width="300">
<mx:FormItem>
<s:Label text="Username" />
<s:TextInput id="username"/>
</mx:FormItem>
<mx:FormItem>
<s:Label text="Email Address" />
<s:TextInput id="emailaddress"/>
</mx:FormItem>
<s:Button label="Submit" click="clickHandler()"/>
</mx:Form>
<mx:DataGrid id="dgUserRequest" x="22" y="200">
<mx:columns>
<mx:DataGridColumn headerText="User ID" dataField="userid"/>
<mx:DataGridColumn headerText="User Name" dataField="username"/>
</mx:columns>
</mx:DataGrid>
</s:Application>
In this application, the RemoteObject component’s destination property is set to Coldfusion and the source
property is set to the fully qualified name of the ColdFusion component.
In contrast, when working with LiveCycle Data Services or BlazeDS, you specify a fully qualified class name in the
source property of a remoting service destination in a configuration file, which by default is the remoting-config.xml
file. You specify the name of the destination in the RemoteObject component’s destination property. The
destination class also must have a no-args constructor. You can optionally configure a destination this way when
working with ColdFusion instead of by using the source property on the RemoteObject component.
ColdFusion component
The application calls the following ColdFusion component. This ColdFusion code performs SQL database inserts and
queries and returns query results to the application. The ColdFusion page uses the cfquery tag to insert data into the
database and query the database, and it uses the cfreturn tag to format the query results as a ColdFusion query object.
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<cfcomponent name="returnusers">
<cffunction name="returnRecords" access="remote" returnType="query">
<cfquery name="alluserinfo" datasource="flexcf">
SELECT userid, username, emailaddress FROM users
</cfquery>
<cfreturn alluserinfo>
</cffunction>
<cffunction name="insertRecord" access="remote" returnType="void">
<cfargument name="username" required="true" type="string">
<cfargument name="emailaddress" required="true" type="string">
<cfquery name="addempinfo" datasource="flexcf">
INSERT INTO users (username, emailaddress) VALUES (
<cfqueryparam value="#arguments.username#" cfsqltype="CF_SQL_VARCHAR"
maxlength="255">,
<cfqueryparam value="#arguments.emailaddress#" cfsqltype="CF_SQL_VARCHAR"
maxlength="255"> )
</cfquery>
<cfreturn>
</cffunction>
</cfcomponent>
Calling RemoteObject components in ActionScript
In the following ActionScript example, calling the useRemoteObject() method declares the service, sets the
destination, sets up result and fault event listeners, and calls the service’s getList() method.
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<?xml version="1.0"?>
<!-- fds\rpc\ROInAS.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
<mx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.rpc.remoting.RemoteObject;
import mx.rpc.events.ResultEvent;
import mx.rpc.events.FaultEvent;
[Bindable]
public var empList:Object;
public var employeeRO:RemoteObject;
public function useRemoteObject(intArg:int, strArg:String):void {
employeeRO = new RemoteObject();
employeeRO.destination = "SalaryManager";
employeeRO.getList.addEventListener("result", getListResultHandler);
employeeRO.addEventListener("fault", faultHandler);
employeeRO.getList(deptComboBox.selectedItem.data);
}
public function getListResultHandler(event:ResultEvent):void {
// Do something
empList=event.result;
}
public function faultHandler (event:FaultEvent):void {
// Deal with event.fault.faultString, etc.
Alert.show(event.fault.faultString, 'Error');
}
]]>
</mx:Script>
<mx:ComboBox id="deptComboBox"/>
</mx:Application>
Accessing Java objects in the source path
The RemoteObject component lets you access stateless and stateful Java objects that are in the LiveCycle Data Services,
BlazeDS, or ColdFusion web application's source path. You can place stand-alone class files in the web application's
WEB-INF/classes directory to add them to the source path. You can place classes contained in Java Archive (JAR) files
in the web application's WEB-INF/lib directory to add them to the source path. You specify the fully qualified class
name in the source property of a remoting service destination in the LiveCycle Data Services, BlazeDS, or ColdFusion
services-config.xml file, or a file that it includes by reference, such as the remoting-config.xml file. The class also must
have a no-args constructor. For ColdFusion, you can optionally set the RemoteObject component’s destination
property to Coldfusion and the source property to the fully qualified name of a ColdFusion component or Java class.
When you configure a remoting service destination to access stateless objects (the request scope), Flex creates a
different object for each method call instead of calling methods on the same object. You can set the scope of an object
to the request scope (default value), the application scope, or the session scope. Objects in the application scope are
available to the web application that contains the object. Objects in the session scope are available to the entire client
session.
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When you configure a remote object destination to access stateful objects, Flex creates the object once on the server
and maintains state between method calls. If storing the object in the application or session scope causes memory
problems, use the request scope.
Accessing EJBs and other objects in JNDI
You can access Enterprise JavaBeans (EJBs) and other objects stored in the Java Naming and Directory Interface
(JNDI) by calling methods on a destination that is a service facade class that looks up an object in JNDI and calls its
methods.
You can use stateless or stateful objects to call the methods of Enterprise JavaBeans and other objects that use JNDI.
For an EJB, you can call a service facade class that returns the EJB object from JNDI and calls a method on the EJB.
In your Java class, you use the standard Java coding pattern, in which you create an initial context and perform a JNDI
lookup. For an EJB, you also use the standard coding pattern in which your class contains methods that call the EJB
home object's create() method and the resulting EJB’s business methods.
The following example uses a method called getHelloData() on a facade class destination:
<mx:RemoteObject id="Hello" destination="roDest">
<mx:method name="getHelloData"/>
</mx:RemoteObject>
On the Java side, the getHelloData() method could encapsulate everything necessary to call a business method on
an EJB. The Java method in the following example performs the following actions:
• Creates new initial context for calling the EJB
• Performs a JNDI lookup that gets an EJB home object
• Calls the EJB home object's create() method
• Calls the EJB’s sayHello() method
...
public void getHelloData() {
try{
InitialContext ctx = new InitialContext();
Object obj = ctx.lookup("/Hello");
HelloHome ejbHome = (HelloHome)
PortableRemoteObject.narrow(obj, HelloHome.class);
HelloObject ejbObject = ejbHome.create();
String message = ejbObject.sayHello();
}
catch (Exception e);
}
...
Reserved method names
The Flex remoting library uses the following method names; do not use these method names as your own method
names:
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addHeader()
addProperty()
deleteHeader()
hasOwnProperty()
isPropertyEnumerable()
isPrototypeOf()
registerClass()
toLocaleString()
toString()
unwatch()
valueOf()
watch()
Also, do not begin method names with an underscore (_) character.
RemoteObject methods (operations) are accessible by simply naming them after the service variable. However,
naming conflicts can occur if an operation name happens to match a defined method on the service. You can use the
following method in ActionScript on a RemoteObject component to return the operation of the given name:
public function getOperation(name:String):Operation
Serializing between ActionScript and Java
LiveCycle Data Services and BlazeDS serialize data between ActionScript (AMF 3) and Java and ColdFusion data types
in both directions. For information about ColdFusion data types, see the ColdFusion documentation set.
Converting data from ActionScript to Java
When method parameters send data from an application to a Java object, the data is automatically converted from an
ActionScript data type to a Java data type. When LiveCycle Data Services or BlazeDS searches for a suitable method
on the Java object, it uses further, more lenient conversions to find a match.
Simple data types on the client, such as Boolean and String values, typically match exactly a remote API. However, Flex
attempts some simple conversions when searching for a suitable method on a Java object.
An ActionScript array can index entries in two ways. A strict array is one in which all indexes are numbers. An
associative array is one in which at least one index is based on a string. It is important to know which type of array you
are sending to the server, because it changes the data type of parameters that are used to invoke a method on a Java
object. A dense array is one in which all numeric indexes are consecutive, with no gap, starting from 0 (zero). A sparse
array is one in which there are gaps between the numeric indexes; the array is treated like an object and the numeric
indexes become properties that are deserialized into a java.util.Map object to avoid sending many null entries.
The following table lists the supported ActionScript (AMF 3) to Java conversions for simple data types.
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ActionScript type (AMF 3)
Deserialization to Java
Supported Java type binding
Array (dense)
java.util.List
java.util.Collection, Object[ ] (native array)
If the type is an interface, it is mapped to the following interface
implementations:
•
List becomes ArrayList
•
SortedSet becomes TreeSet
•
Set becomes HashSet
•
Collection becomes ArrayList
A new instance of a custom Collection implementation is bound to
that type.
Array (sparse)
java.util.Map
java.util.Map
Boolean
java.lang.Boolean
Boolean, boolean, String
String of "true" or "false"
flash.utils.ByteArray
byte []
flash.utils.IExternalizable
java.io.Externalizable
Date
java.util.Date
(formatted for Coordinated
Universal Time (UTC))
java.util.Date, java.util.Calendar, java.sql.Timestamp, java.sql.Time,
java.sql.Date
int/uint
java.lang.Integer
java.lang.Double, java.lang.Long, java.lang.Float, java.lang.Integer,
java.lang.Short, java.lang.Byte, java.math.BigDecimal,
java.math.BigInteger, String, primitive types of double, long, float,
int, short, byte
null
null
primitives
Number
java.lang.Double
java.lang.Double, java.lang.Long, java.lang.Float, java.lang.Integer,
java.lang.Short, java.lang.Byte, java.math.BigDecimal,
java.math.BigInteger, String, 0 (zero)
if null is sent, primitive types of double, long, float, int, short, byte
Object (generic)
java.util.Map
If a Map interface is specified, creates a java.util.HashMap for
java.util.Map and a new java.util.TreeMap for java.util.SortedMap.
String
java.lang.String
java.lang.String, java.lang.Boolean, java.lang.Number,
java.math.BigInteger, java.math.BigDecimal, char[], any primitive
number type
typed Object
typed Object
typed Object
When you use [RemoteClass]
metadata tag that specifies
remote class name. Bean type
must have a public no args
constructor.
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ActionScript type (AMF 3)
Deserialization to Java
Supported Java type binding
undefined
null
null for object, default values for primitives
XML
org.w3c.dom.Document
org.w3c.dom.Document
XMLDocument
org.w3c.dom.Document
org.w3c.dom.Document
(legacy XML type)
You can enable legacy XML support for the XMLDocument type on
any channel defined in the services-config.xml file. This setting is
important only for sending data from the server back to the client; it
controls how org.w3c.dom.Document instances are sent to
ActionScript. For more information, see Configuring AMF
serialization on a channel.
Primitive values cannot be set to null in Java. When passing Boolean and Number values from the client to a Java
object, Flex interprets null values as the default values for primitive types; for example, 0 for double, float, long, int,
short, byte, \u0000 for char, and false for Boolean. Only primitive Java types get default values.
LiveCycle Data Services and BlazeDS handle java.lang.Throwable objects like any other typed object. They are
processed with rules that look for public fields and bean properties, and typed objects are returned to the client. The
rules are like normal bean rules except that they look for getters for read-only properties. This lets you get more
information from a Java exception. If you require legacy behavior for Throwable objects, you can set the legacythrowable property to true on a channel; for more information, see Configuring AMF serialization on a channel.
You can pass strict arrays as parameters to methods that expect an implementation of the java.util.Collection or native
Java Array APIs.
A Java Collection can contain any number of object types, whereas a Java Array requires that entries are the same type
(for example, java.lang.Object[ ], and int[ ]).
LiveCycle Data Services and BlazeDS also convert ActionScript strict arrays to appropriate implementations for
common Collection API interfaces. For example, if an ActionScript strict array is sent to the Java object method
public void addProducts(java.util.Set products), LiveCycle Data Services and BlazeDS convert it to a
java.util.HashSet instance before passing it as a parameter, because HashSet is a suitable implementation of the
java.util.Set interface. Similarly, LiveCycle Data Services and BlazeDS pass an instance of java.util.TreeSet to
parameters typed with the java.util.SortedSet interface.
LiveCycle Data Services and BlazeDS pass an instance of java.util.ArrayList to parameters typed with the java.util.List
interface and any other interface that extends java.util.Collection. Then these types are sent back to the client as
mx.collections.ArrayCollection instances. If you require normal ActionScript arrays to be sent back to the client, you
must set the legacy-collection element to true in the serialization section of a channel-definition's properties.
For more information, see Configuring AMF serialization on a channel.
Explicitly mapping ActionScript and Java objects
For Java objects that LiveCycle Data Services and BlazeDS do not handle implicitly, values found in public bean
properties with get/set methods and public variables are sent to the client as properties on an 0bject. Private properties,
constants, static properties, read-only properties, and so on are not serialized. For ActionScript objects, public
properties defined with the get/set accessors and public variables are sent to the server.
LiveCycle Data Services and BlazeDS use the standard Java class, java.beans.Introspector, to get property descriptors
for a JavaBean class. It also uses reflection to gather public fields on a class. It uses bean properties in preference to
fields. The Java and ActionScript property names should match. Native Flash Player code determines how
ActionScript classes are introspected on the client.
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In the ActionScript class, you use the [RemoteClass(alias=" ")] metadata tag to create an ActionScript object that
maps directly to the Java object. The ActionScript class to which data is converted must be used or referenced in the
MXML file for it to be linked into the SWF file and available at runtime. A good way to do this is by casting the result
object, as the following example shows:
var result:MyClass = MyClass(event.result);
The class itself should use strongly typed references so that its dependencies are also linked.
The following examples shows the source code for an ActionScript class that uses the [RemoteClass(alias=" ")]
metadata tag:
package samples.contact {
[Bindable]
[RemoteClass(alias="samples.contact.Contact")]
public class Contact {
public var contactId:int;
public var firstName:String;
public var lastName:String;
public var address:String;
public var city:String;
public var state:String;
public var zip:String;
}
}
You can use the [RemoteClass] metadata tag without an alias if you do not map to a Java object on the server, but
you do send back your object type from the server. Your ActionScript object is serialized to a special Map object when
it is sent to the server, but the object returned from the server to the clients is your original ActionScript type.
To restrict a specific property from being sent to the server from an ActionScript class, use the [Transient] metadata
tag above the declaration of that property in the ActionScript class.
Converting data from Java to ActionScript
An object returned from a Java method is converted from Java to ActionScript. LiveCycle Data Services and BlazeDS
also handle objects found within objects. LiveCycle Data Services implicitly handles the Java data types in the following
table.
Java type
ActionScript type (AMF 3)
java.lang.String
String
java.lang.Boolean, boolean
Boolean
java.lang.Integer, int
int
If value < 0xF0000000 || value > 0x0FFFFFFF, the value is promoted to Number due to AMF
encoding requirements.
java.lang.Short, short
int
If i < 0xF0000000 || i > 0x0FFFFFFF, the value is promoted to Number.
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Java type
ActionScript type (AMF 3)
java.lang.Byte, byte[]
int
If i < 0xF0000000 || i > 0x0FFFFFFF, the value is promoted to Number.
java.lang.Byte[]
flash.utils.ByteArray
java.lang.Double, double
Number
java.lang.Long, long
Number
java.lang.Float, float
Number
java.lang.Character, char
String
java.lang.Character[], char[]
String
java. math.BigInteger
String
java.math.BigDecimal
String
java.util.Calendar
Date
Dates are sent in the Coordinated Universal Time (UTC) time zone. Clients and servers must
adjust time accordingly for time zones.
java.util.Date
Date
Dates are sent in the UTC time zone. Clients and servers must adjust time accordingly for time
zones.
java.util.Collection (for example,
java.util.ArrayList)
mx.collections.ArrayCollection
java.lang.Object[]
Array
java.util.Map
Object (untyped). For example, a java.util.Map[] is converted to an array (of objects).
java.util.Dictionary
Object (untyped)
org.w3c.dom.Document
XML object
null
null
java.lang.Object (other than previously
listed types)
Typed Object
Objects are serialized by using JavaBean introspection rules and also include public fields.
Fields that are static, transient, or nonpublic, as well as bean properties that are nonpublic or
static, are excluded.
Configuring AMF serialization on a channel
You can support legacy AMF type serialization used in earlier versions of Flex and configure other serialization
properties in channel definitions in the services-config.xml file.
The following table describes the properties you can set in the <serialization> element of a channel definition:
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Property
Description
<ignore-property-errors>true</ignore-property-errors>
Default value is true. Determines if the endpoint should
throw an error when an incoming client object has
unexpected properties that cannot be set on the server
object.
<log-property-errors>false</log-property-errors>
Default value is false. When true, unexpected property
errors are logged.
<legacy-collection>false</legacy-collection>
Default value is false. When true, instances of
java.util.Collection are returned as ActionScript arrays.
When false, instances of java.util.Collection are returned
as mx.collections.ArrayCollection.
<legacy-map>false</legacy-map>
Default value is false. When true, java.util.Map instances
are serialized as an ECMA array or associative array instead
of an anonymous object.
<legacy-xml>false</legacy-xml>
Default value is false. When true,
org.w3c.dom.Document instances are serialized as
flash.xml.XMLDocument instances instead of intrinsic XML
(E4X capable) instances.
<legacy-throwable>false</legacy-throwable>
Default value is false. When true, java.lang.Throwable
instances are serialized as AMF status-info objects (instead
of normal bean serialization, including read-only
properties).
<type-marshaller>className</type-marshaller>
Specifies an implementation of
flex.messaging.io.TypeMarshaller that translates an object
into an instance of a desired class. Used when invoking a
Java method or populating a Java instance and the type of
the input object from deserialization (for example, an
ActionScript anonymous object is always deserialized as a
java.util.HashMap) doesn't match the destination API (for
example, java.util.SortedMap). Thus the type can be
marshalled into the desired type.
<restore-references>false</restore-references>
Default value is false. An advanced switch to make the
deserializer keep track of object references when a type
translation has to be made; for example, when an
anonymous object is sent for a property of type
java.util.SortedMap, the object is first deserialized to a
java.util.Map as normal, and then translated to a suitable
implementation of SortedMap (such as java.util.TreeMap). If
other objects pointed to the same anonymous object in an
object graph, this setting restores those references instead
of creating SortedMap implementations everywhere.
Notice that setting this property to true can slow down
performance significantly for large amounts of data.
<instantiate-types>true</instantiate-types>
Default value is true. Advanced switch that when set to
false stops the deserializer from creating instances of
strongly typed objects and instead retains the type
information and deserializes the raw properties in a Map
implementation, specifically flex.messaging.io.ASObject.
Notice that any classes under flex.* package are always
instantiated.
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Using custom serialization
If the standard mechanisms for serializing and deserializing data between ActionScript on the client and Java on the
server do not meet your needs, you can write your own serialization scheme. You implement the ActionScript-based
flash.utils.IExternalizable interface on the client and the corresponding Java-based java.io.Externalizable interface on
the server.
A typical reason to use custom serialization is to avoid passing all of the properties of either the client-side or serverside representation of an object across the network tier. When you implement custom serialization, you can code your
classes so that specific properties that are client-only or server-only are not passed over the wire. When you use the
standard serialization scheme, all public properties are passed back and forth between the client and the server.
On the client side, the identity of a class that implements the flash.utils.IExternalizable interface is written in the
serialization stream. The class serializes and reconstructs the state of its instances. The class implements the
writeExternal() and readExternal() methods of the IExternalizable interface to get control over the contents and
format of the serialization stream, but not the class name or type, for an object and its supertypes. These methods
supersede the native AMF serialization behavior. These methods must be symmetrical with their remote counterpart
to save the class's state.
On the server side, a Java class that implements the java.io.Externalizable interface performs functionality that is
analogous to an ActionScript class that implements the flash.utils.IExternalizable interface.
Note: If precise by-reference serialization is required, do not use types that implement the IExternalizable interface with
the HTTPChannel. When you do this, references between recurring objects are lost and appear to be cloned at the
endpoint.
The following example shows the complete source code for the client (ActionScript) version of a Product class that
maps to a Java-based Product class on the server. The client Product implements the IExternalizable interface, and the
server Product implements the Externalizable interface.
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// Product.as
package samples.externalizable {
import flash.utils.IExternalizable;
import flash.utils.IDataInput;
import flash.utils.IDataOutput;
[RemoteClass(alias="samples.externalizable.Product")]
public class Product implements IExternalizable {
public function Product(name:String=null) {
this.name = name;
}
public
public
public
public
var
var
var
var
id:int;
name:String;
properties:Object;
price:Number;
public function readExternal(input:IDataInput):void {
name = input.readObject() as String;
properties = input.readObject();
price = input.readFloat();
}
public function writeExternal(output:IDataOutput):void {
output.writeObject(name);
output.writeObject(properties);
output.writeFloat(price);
}
}
}
The client Product uses two kinds of serialization. It uses the standard serialization that is compatible with the
java.io.Externalizable interface and AMF 3 serialization. The following example shows the writeExternal() method
of the client Product, which uses both types of serialization:
public function writeExternal(output:IDataOutput):void {
output.writeObject(name);
output.writeObject(properties);
output.writeFloat(price);
}
As the following example shows, the writeExternal() method of the server Product is almost identical to the client
version of this method:
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(name);
out.writeObject(properties);
out.writeFloat(price);
}
In the client Product’s writeExternal() method, the flash.utils.IDataOutput.writeFloat() method is an
example of standard serialization methods that meet the specifications for the Java
java.io.DataInput.readFloat() methods for working with primitive types. This method sends the price
property, which is a Float, to the server Product.
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The example of AMF 3 serialization in the client Product’s writeExternal() method is the call to the
flash.utils.IDataOutput.writeObject() method, which maps to the java.io.ObjectInput.readObject()
method call in the server Product’s readExternal() method. The flash.utils.IDataOutput.writeObject()
method sends the properties property, which is an object, and the name property, which is a string, to the server
Product. This is possible because the AMFChannel endpoint has an implementation of the java.io.ObjectInput
interface that expects data sent from the writeObject() method to be formatted as AMF 3.
In turn, when the readObject() method is called in the server Product’s readExternal() method, it uses AMF 3
deserialization; this is why the ActionScript version of the properties value is assumed to be of type Map and name
is assumed to be of type String.
The following example shows the complete source of the server Product class:
// Product.java
package samples.externalizable;
import
import
import
import
import
java.io.Externalizable;
java.io.IOException;
java.io.ObjectInput;
java.io.ObjectOutput;
java.util.Map;
/**
* This Externalizable class requires that clients sending and
* receiving instances of this type adhere to the data format
* required for serialization.
*/
public class Product implements Externalizable {
private String inventoryId;
public String name;
public Map properties;
public float price;
public Product()
{
}
/**
* Local identity used to track third-party inventory. This property is
* not sent to the client because it is server specific.
* The identity must start with an 'X'.
*/
public String getInventoryId() {
return inventoryId;
}
public void setInventoryId(String inventoryId) {
if (inventoryId != null && inventoryId.startsWith("X"))
{
this.inventoryId = inventoryId;
}
else
{
throw new IllegalArgumentException("3rd party product
inventory identities must start with 'X'");
}
}
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/**
* Deserializes the client state of an instance of ThirdPartyProxy
* by reading in String for the name, a Map of properties
* for the description, and
* a floating point integer (single precision) for the price.
*/
public void readExternal(ObjectInput in) throws IOException,
ClassNotFoundException {
// Read in the server properties from the client representation.
name = (String)in.readObject();
properties = (Map)in.readObject();
price = in.readFloat();
setInventoryId(lookupInventoryId(name, price));
}
/**
* Serializes the server state of an instance of ThirdPartyProxy
* by sending a String for the name, a Map of properties
* String for the description, and a floating point
* integer (single precision) for the price. Notice that the inventory
* identifier is not sent to external clients.
*/
public void writeExternal(ObjectOutput out) throws IOException {
// Write out the client properties from the server representation.
out.writeObject(name);
out.writeObject(properties);
out.writeFloat(price);
}
private static String lookupInventoryId(String name, float price) {
String inventoryId = "X" + name + Math.rint(price);
return inventoryId;
}
}
The following example shows the server Product’s readExternal() method:
public void readExternal(ObjectInput in) throws IOException,
ClassNotFoundException {
// Read in the server properties from the client representation.
name = (String)in.readObject();
properties = (Map)in.readObject();
price = in.readFloat();
setInventoryId(lookupInventoryId(name, price));
}
The client Product’s writeExternal() method does not send the id property to the server during serialization
because it is not useful to the server version of the Product object. Similarly, the server Product’s writeExternal()
method does not send the inventoryId property to the client because it is a server-specific property.
Notice that the names of a Product’s properties are not sent during serialization in either direction. Because the state
of the class is fixed and manageable, the properties are sent in a well-defined order without their names, and the
readExternal() method reads them in the appropriate order.
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Explicit parameter passing and parameter binding
There are two distinct ways to call HTTPService, WebService, and RemoteObject components: explicit parameter
passing and parameter binding. When you use explicit parameter passing, you provide input to a service in the form
of parameters to an ActionScript function. This way of calling a service closely resembles the way that you call methods
in Java. You cannot use Flex data validators automatically in combination with explicit parameter passing.
Parameter binding lets you copy data from user-interface controls or models to request parameters. Parameter binding
is available only for data access components that you declare in MXML. You can apply validators to parameter values
before submitting requests to services. For more information about data binding and data models, see Data binding
and Storing data. For more information about data validation, see Validating Data.
When you use parameter binding, you declare RemoteObject method parameter tags nested in an <mx:arguments>
tag under an <mx:method> tag, HTTPService parameter tags nested in an <mx:request> tag, or WebService operation
parameter tags nested in an <mx:request> tag under an <mx:operation> tag. You use the send() method to send
the request.
Explicit parameter passing with RemoteObject and WebService components
The way you use explicit parameter passing with RemoteObject and WebService components is very similar. The
following example shows MXML code for declaring a RemoteObject component and calling a service by using explicit
parameter passing in the click event listener of a Button control. A ComboBox control provides data to the service.
Simple event listeners handle the service-level result and fault events.
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<?xml version="1.0"?>
<!-- fds\rpc\RPCParamPassing.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
verticalGap="10">
<mx:Script>
<![CDATA[
import mx.controls.Alert;
[Bindable]
public var empList:Object;
]]>
</mx:Script>
<mx:RemoteObject
id="employeeRO"
destination="SalaryManager"
result="empList=event.result"
fault="Alert.show(event.fault.faultString, 'Error');"/>
<mx:ComboBox id="dept" width="150">
<mx:dataProvider>
<mx:ArrayCollection>
<mx:source>
<mx:Object label="Engineering" data="ENG"/>
<mx:Object label="Product Management" data="PM"/>
<mx:Object label="Marketing" data="MKT"/>
</mx:source>
</mx:ArrayCollection>
</mx:dataProvider>
</mx:ComboBox>
<mx:Button label="Get Employee List" click="employeeRO.getList(dept.selectedItem.data);"/>
</mx:Application>
Explicit parameter passing with HTTPService components
Explicit parameter passing with HTTPService components is different than it is with RemoteObject and WebService
components. You always use an HTTPService component’s send() method to call a service. This is different from
RemoteObject and WebService components, on which you call methods that are client-side versions of the methods
or operations of the RPC service.
When you use explicit parameter passing, you can specify an object that contains name-value pairs as a send()
method parameter. A send() method parameter must be a simple base type; you cannot use complex nested objects
because there is no generic way to convert them to name-value pairs.
If you do not specify a parameter to the send() method, the HTTPService component uses any query parameters
specified in an <mx:request> tag.
The following examples show two ways to call an HTTP service by using the send() method with a parameter. The
second example also shows how to call the cancel() method to cancel an HTTP service call.
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<?xml version="1.0"?>
<!-- fds\rpc\RPCSend.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
<mx:Script>
<![CDATA[
public function callService():void {
// Cancel all previous pending calls.
myService.cancel();
var params:Object = new Object();
params.param1 = 'val1';
myService.send(params);
}
]]>
</mx:Script>
<mx:HTTPService
id="myService"
destination="Dest"
useProxy="true"/>
<!-- HTTP service call with a send() method that takes a variable as its parameter. The value
of the variable is an Object. -->
<mx:Button click="myService.send({param1: 'val1'});"/>
<!-- HTTP service call with an object as a send() method parameter that provides query
parameters. -->
<mx:Button click="callService();"/>
</mx:Application>
Parameter binding with RemoteObject components
When you use parameter binding with RemoteObject components, you always declare methods in a RemoteObject
component’s <mx:method> tag.
An <mx:method> tag can contain an <mx:arguments> tag that contains child tags for the method parameters. The
name property of an <mx:method> tag must match one of the service’s method names. The order of the argument tags
must match the order of the service’s method parameters. You can name argument tags to match the actual names of
the corresponding method parameters as closely as possible, but this is not necessary.
Note: If argument tags inside an <mx:arguments> tag have the same name, service calls fail if the remote method is not
expecting an array as the only input source. There is no warning about this when the application is compiled.
You can bind data to a RemoteObject component’s method parameters. You reference the tag names of the parameters
for data binding and validation.
The following example shows a method with two parameters bound to the text properties of TextInput controls. A
PhoneNumberValidator validator is assigned to arg1, which is the name of the first argument tag.
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<?xml version="1.0"?>
<!-- fds\rpc\ROParamBind1.mxml. -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
<mx:RemoteObject
id="ro"
destination="roDest">
<mx:method name="setData">
<mx:arguments>
<arg1>{text1.text}</arg1>
<arg2>{text2.text}</arg2>
</mx:arguments>
</mx:method>
</mx:RemoteObject>
<mx:TextInput id="text1"/>
<mx:TextInput id="text2"/>
<mx:PhoneNumberValidator source="{ro.setData.arguments}" property="arg1"/>
</mx:Application>
Flex sends the argument tag values to the method in the order that the MXML tags specify.
The following example uses parameter binding in a RemoteObject component’s <mx:method> tag to bind the data of
a selected ComboBox item to the employeeRO.getList operation when the user clicks a Button control. When you
use parameter binding, you call a service by using the send() method with no parameters.
<?xml version="1.0"?>
<!-- fds\rpc\ROParamBind2.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" verticalGap="10">
<mx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.utils.ArrayUtil;
]]>
</mx:Script>
<mx:RemoteObject
id="employeeRO"
destination="roDest"
showBusyCursor="true"
fault="Alert.show(event.fault.faultString, 'Error');">
<mx:method name="getList">
<mx:arguments>
<deptId>{dept.selectedItem.data}</deptId>
</mx:arguments>
</mx:method>
</mx:RemoteObject>
<mx:ArrayCollection id="employeeAC"
source="{ArrayUtil.toArray(employeeRO.getList.lastResult)}"/>
<mx:HBox>
<mx:Label text="Select a department:"/>
<mx:ComboBox id="dept" width="150">
<mx:dataProvider>
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<mx:ArrayCollection>
<mx:source>
<mx:Object label="Engineering" data="ENG"/>
<mx:Object label="Product Management" data="PM"/>
<mx:Object label="Marketing" data="MKT"/>
</mx:source>
</mx:ArrayCollection>
</mx:dataProvider>
</mx:ComboBox>
<mx:Button label="Get Employee List"
click="employeeRO.getList.send()"/>
</mx:HBox>
<mx:DataGrid dataProvider="{employeeAC}" width="100%">
<mx:columns>
<mx:DataGridColumn dataField="name" headerText="Name"/>
<mx:DataGridColumn dataField="phone" headerText="Phone"/>
<mx:DataGridColumn dataField="email" headerText="Email"/>
</mx:columns>
</mx:DataGrid>
</mx:Application>
If you are unsure whether the result of a service call contains an array or an individual object, you can use the
toArray() method of the mx.utils.ArrayUtil class to convert it to an array, as this example shows. If you pass the
toArray() method to an individual object, it returns an array with that object as the only Array element. If you pass
an array to the method, it returns the same array. For information about working with ArrayCollection objects, see
Data providers and collections.
Parameter binding with HTTPService components
When an HTTP service takes query parameters, you can declare them as child tags of an <mx:request> tag. The
names of the tags must match the names of the query parameters that the service expects.
The following example uses parameter binding in an HTTPService component’s <mx:request> tag to bind the data
of a selected ComboBox item to the employeeSrv request when the user clicks a Button control. When you use
parameter binding, you call a service by using the send() method with no parameters. This example shows a url
property on the HTTPService component, but the way you call a service is the same whether you connect to the service
directly or go through a destination.
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<?xml version="1.0"?>
<!-- fds\rpc\HttpServiceParamBind.mxml. Compiles -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" verticalGap="20">
<mx:Script>
<![CDATA[
import mx.utils.ArrayUtil;
]]>
</mx:Script>
<mx:HTTPService
id="employeeSrv"
url="employees.jsp">
<mx:request>
<deptId>{dept.selectedItem.data}</deptId>
</mx:request>
</mx:HTTPService>
<mx:ArrayCollection
id="employeeAC"
source=
"{ArrayUtil.toArray(employeeSrv.lastResult.employees.employee)}"/>
<mx:HBox>
<mx:Label text="Select a department:"/>
<mx:ComboBox id="dept" width="150">
<mx:dataProvider>
<mx:ArrayCollection>
<mx:source>
<mx:Object label="Engineering" data="ENG"/>
<mx:Object label="Product Management" data="PM"/>
<mx:Object label="Marketing" data="MKT"/>
</mx:source>
</mx:ArrayCollection>
</mx:dataProvider>
</mx:ComboBox>
<mx:Button label="Get Employee List" click="employeeSrv.send();"/>
</mx:HBox>
<mx:DataGrid dataProvider="{employeeAC}"
width="100%">
<mx:columns>
<mx:DataGridColumn dataField="name" headerText="Name"/>
<mx:DataGridColumn dataField="phone" headerText="Phone"/>
<mx:DataGridColumn dataField="email" headerText="Email"/>
</mx:columns>
</mx:DataGrid>
</mx:Application>
If you are unsure whether the result of a service call contains an array or an individual object, you can use the
toArray() method of the mx.utils.ArrayUtil class to convert it to an array, as the previous example shows. If you pass
the toArray() method to an individual object, it returns an array with that object as the only Array element. If you
pass an array to the method, it returns the same array. For information about working with ArrayCollection objects,
see Data providers and collections.
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Parameter binding with WebService components
When you use parameter binding with a WebService component, you always declare operations in the WebService
component’s <mx:operation> tags. An <mx:operation> tag can contain an <mx:request> tag that contains the
XML nodes that the operation expects. The name property of an <mx:operation> tag must match one of the web
service operation names.
You can bind data to parameters of web service operations. You reference the tag names of the parameters for data
binding and validation.
The following example uses parameter binding in a WebService component’s <mx:operation> tag to bind the data of
a selected ComboBox item to the employeeWS.getList operation when the user clicks a Button control. The
<deptId> tag corresponds directly to the getList operation’s deptId parameter. When you use parameter binding, you
call a service by using the send() method with no parameters. This example shows a destination property on the
WebService component, but the way you call a service is the same whether you connect to the service directly or go
through a destination.
<?xml version="1.0"?>
<!-- fds\rpc\WebServiceParamBind.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" verticalGap="10">
<mx:Script>
<![CDATA[
import mx.utils.ArrayUtil;
import mx.controls.Alert;
]]>
</mx:Script>
<mx:WebService
id="employeeWS"
destination="wsDest"
showBusyCursor="true"
fault="Alert.show(event.fault.faultString)">
<mx:operation name="getList">
<mx:request>
<deptId>{dept.selectedItem.data}</deptId>
</mx:request>
</mx:operation>
</mx:WebService>
<mx:ArrayCollection
id="employeeAC"
source="{ArrayUtil.toArray(employeeWS.getList.lastResult)}"/>
<mx:HBox>
<mx:Label text="Select a department:"/>
<mx:ComboBox id="dept" width="150">
<mx:dataProvider>
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<mx:ArrayCollection>
<mx:source>
<mx:Object label="Engineering" data="ENG"/>
<mx:Object label="Product Management" data="PM"/>
<mx:Object label="Marketing" data="MKT"/>
</mx:source>
</mx:ArrayCollection>
</mx:dataProvider>
</mx:ComboBox>
<mx:Button label="Get Employee List"
click="employeeWS.getList.send()"/>
</mx:HBox>
<mx:DataGrid dataProvider="{employeeAC}" width="100%">
<mx:columns>
<mx:DataGridColumn dataField="name" headerText="Name"/>
<mx:DataGridColumn dataField="phone" headerText="Phone"/>
<mx:DataGridColumn dataField=" to email" headerText="Email"/>
</mx:columns>
</mx:DataGrid>
</mx:Application>
You can also manually specify an entire SOAP request body in XML with all of the correct namespace information
defined in an <mx:request> tag. To do so, set the value of the format attribute of the <mx:request> tag to xml, as
the following example shows:
<?xml version="1.0"?>
<!-- fds\rpc\WebServiceSOAPRequest.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" verticalGap="10">
<mx:WebService id="ws" wsdl="http://api.google.com/GoogleSearch.wsdl"
useProxy="true">
<mx:operation name="doGoogleSearch" resultFormat="xml">
<mx:request format="xml">
<ns1:doGoogleSearch xmlns:ns1="urn:GoogleSearch"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<key xsi:type="xsd:string">XYZ123</key>
<q xsi:type="xsd:string">Balloons</q>
<start xsi:type="xsd:int">0</start>
<maxResults xsi:type="xsd:int">10</maxResults>
<filter xsi:type="xsd:boolean">true</filter>
<restrict xsi:type="xsd:string"/>
<safeSearch xsi:type="xsd:boolean">false</safeSearch>
<lr xsi:type="xsd:string" />
<ie xsi:type="xsd:string">latin1</ie>
<oe xsi:type="xsd:string">latin1</oe>
</ns1:doGoogleSearch>
</mx:request>
</mx:operation>
</mx:WebService>
</mx:Application>
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Handling service results
After an RPC component calls a service, the data that the service returns is placed in a lastResult object. By default, the
resultFormat property value of HTTPService components and WebService component operations is object, and
the data that is returned is represented as a simple tree of ActionScript objects. Flex interprets the XML data that a web
service or HTTP service returns to appropriately represent base types, such as String, Number, Boolean, and Date. To
work with strongly typed objects, populate those objects by using the object tree that Flex creates.
WebService and HTTPService components both return anonymous objects and arrays that are complex types. If
makeObjectsBindable is true, which it is by default, objects are wrapped in mx.utils.ObjectProxy instances and
arrays are wrapped in mx.collections.ArrayCollection instances.
Note: ColdFusion is not case sensitive, so it internally uppercases all of its data. Keep this in mind when consuming a
ColdFusion web service.
Handling result and fault events
When a service call is completed, the RemoteObject method, WebService operation, or HTTPService component
dispatches a result event or a fault event. A result event indicates that the result is available. A fault event indicates that
an error occurred. The result event acts as a trigger to update properties that are bound to the lastResult. You can
handle fault and result events explicitly by adding event listeners to RemoteObject methods or WebService operations.
For an HTTPService component, you specify result and fault event listeners on the component itself because an
HTTPService component does not have multiple operations or methods.
When you do not specify event listeners for result or fault events on a RemoteObject method or a WebService
operation, the events are passed to the component level; you can specify component-level result and fault event
listeners.
In the following MXML example, the result and fault events of a WebService operation specify event listeners; the
fault event of the WebService component also specifies an event listener:
<?xml version="1.0"?>
<!-- fds\rpc\RPCResultFaultMXML.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
<mx:Script>
<![CDATA[
import mx.rpc.soap.SOAPFault;
import mx.rpc.events.ResultEvent;
import mx.rpc.events.FaultEvent;
import mx.controls.Alert;
public function showErrorDialog(event:FaultEvent):void {
// Handle operation fault.
Alert.show(event.fault.faultString, "Error");
}
public function defaultFault(event:FaultEvent):void {
// Handle service fault.
if (event.fault is SOAPFault) {
var fault:SOAPFault=event.fault as SOAPFault;
var faultElement:XML=fault.element;
// You could use E4X to traverse the raw fault element returned in the
SOAP envelope.
// ...
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}
Alert.show(event.fault.faultString, "Error");
}
public function log(event:ResultEvent):void {
// Handle result.
}
]]>
</mx:Script>
<mx:WebService id="WeatherService" wsdl="http://myserver:8500/flexapp/app1.cfc?wsdl"
fault="defaultFault(event)">
<mx:operation name="GetWeather"
fault="showErrorDialog(event)"
result="log(event)">
<mx:request>
<ZipCode>{myZip.text}</ZipCode>
</mx:request>
</mx:operation>
</mx:WebService>
<mx:TextInput id="myZip"/>
</mx:Application>
In the following ActionScript example, a result event listener is added to a WebService operation; a fault event listener
is added to the WebService component:
<?xml version="1.0"?>
<!-- fds\rpc\RPCResultFaultAS.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml">
<mx:Script>
<![CDATA[
import mx.rpc.soap.WebService;
import mx.rpc.soap.SOAPFault;
import mx.rpc.events.ResultEvent;
import mx.rpc.events.FaultEvent;
private var ws:WebService;
public function useWebService(intArg:int, strArg:String):void {
ws = new WebService();
ws.destination = "wsDest";
ws.echoArgs.addEventListener("result", echoResultHandler);
ws.addEventListener("fault", faultHandler);
ws.loadWSDL();
ws.echoArgs(intArg, strArg);
}
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public function echoResultHandler(event:ResultEvent):void {
var retStr:String = event.result.echoStr;
var retInt:int = event.result.echoInt;
//do something
}
public function faultHandler(event:FaultEvent):void {
//deal with event.fault.faultString, etc.
if (event.fault is SOAPFault) {
var fault:SOAPFault=event.fault as SOAPFault;
var faultElement:XML=fault.element;
// You could use E4X to traverse the raw fault element returned in the
SOAP envelope.
// ...
}
}
]]>
</mx:Script>
</mx:Application>
You can also use the mx.rpc.events.InvokeEvent event to indicate when a data access component request has been
invoked. This is useful if operations are queued and invoked at a later time.
Handling results as XML with the e4x result format
You can set the resultFormat property value of HTTPService components and WebService operations to e4x to
create a lastResult property of type XML. You can access the lastResult property by using ECMAScript for XML
(E4X) expressions. You do not include the root node of the XML structure in the dot notation when using an E4X XML
object in a binding expression; this is different from the syntax for a lastResult property set to object for which you
do include the root node of the XML structure in the dot notation. For example, when the lastResult property is set to
e4x, you would use {srv.lastResult.product}; when the lastResult property is set to object, you would use
{srv.lastResult.products.product}.
Using a result format of e4x is the preferred way to work directly with XML, but you can also set the resultFormat
property to xml to create a lastResult object of type flash.xml.XMLNode, which is a legacy object for working with
XML. Also, you can set the resultFormat property of HTTPService components to flashvars or text to create
results as ActionScript objects that contain name-value pairs or as raw text, respectively.
Note: To use E4X syntax on service results, you must set the resultFormat property of your HTTPService or WebService
component to e4x. The default value is object.
When you set the resultFormat property of an HTTPService component or WebService operation to e4x, you may
have to handle namespace information contained in the XML that is returned. For a WebService component,
namespace information is included in the body of the SOAP envelope that the web service returns. The following
example shows part of a SOAP body that contains namespace information. This data was returned by a web service
that gets stock quotes. The namespace information is in bold text.
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...
<soap:Body>
<GetQuoteResponse
xmlns="http://ws.invesbot.com/">
<GetQuoteResult><StockQuote xmlns="">
<Symbol>ADBE</Symbol>
<Company>ADOBE SYSTEMS INC</Company>
<Price>&lt;big&gt;&lt;b&gt;35.90&lt;/b&gt;&lt;/big&gt;</Price>
...
</soap:Body>
...
Because this soap:Body contains namespace information, if you set the resultFormat property of the WebService
operation to e4x, create a namespace object for the http://ws.invesbot.com/namespace. The following example shows
an application that does this:
<?xml version="1.0"?>
<!-- fds\rpc\WebServiceE4XResult1.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" xmlns="*"
pageTitle="Test" >
<mx:Script>
<![CDATA[
import mx.controls.Alert;
private namespace invesbot = "http://ws.invesbot.com/";
use namespace invesbot;
]]>
</mx:Script>
<mx:WebService
id="WS"
destination="stockservice" useProxy="true"
fault="Alert.show(event.fault.faultString), 'Error'">
<mx:operation name="GetQuote" resultFormat="e4x">
<mx:request>
<symbol>ADBE</symbol>
</mx:request>
</mx:operation>
</mx:WebService>
<mx:HBox>
<mx:Button label="Get Quote" click="WS.GetQuote.send()"/>
<mx:Text
text="{WS.GetQuote.lastResult.GetQuoteResult.StockQuote.Price}"
/>
</mx:HBox>
</mx:Application>
Optionally, you can create a var for a namespace and access it in a binding to the service result, as the following
example shows:
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<?xml version="1.0"?>
<!-- fds\rpc\WebServiceE4XResult2.mxml -->
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" xmlns="*"
pageTitle="Test" >
<mx:Script>
<![CDATA[
import mx.controls.Alert;
public var invesbot:Namespace =
new Namespace("http://ws.invesbot.com/");
]]>
</mx:Script>
<mx:WebService
id="WS"
destination="stockservice" useProxy="true"
fault="Alert.show(event.fault.faultString), 'Error'">
<mx:operation name="GetQuote" resultFormat="e4x">
<mx:request>
<symbol>ADBE</symbol>
</mx:request>
</mx:operation>
</mx:WebService>
<mx:HBox>
<mx:Button label="Get Quote" click="WS.GetQuote.send()"/>
<mx:Text
text="{WS.GetQuote.lastResult.invesbot::GetQuoteResult.StockQuote.Price}"
/>
</mx:HBox>
</mx:Application>
You use E4X syntax to access elements and attributes of the XML that is returned in a lastResult object. You use
different syntax, depending on whether a namespace or namespaces are declared in the XML.
No namespace
The following example shows how to get an element or attribute value when no namespace is specified on the element
or attribute:
var attributes:XMLList = XML(event.result).Description.value;
The previous code returns xxx for the following XML document:
<RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<Description>
<value>xxx</value>
</Description>
</RDF>
Any namespace
The following example shows how to get an element or attribute value when any namespace is specified on the element
or attribute:
var attributes:XMLList = XML(event.result).*::Description.*::value;
The previous code returns xxx for either one of the following XML documents:
XML document one:
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<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdf:Description>
<rdf:value>xxx</rdf:value>
</rdf:Description>
</rdf:RDF>
XML document two:
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:cm="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<cm:Description>
<rdf:value>xxx</rdf:value>
</cm:Description>
</rdf:RDF>
Specific namespace
The following example shows how to get an element or attribute value when the declared rdf namespace is specified
on the element or attribute:
var rdf:Namespace = new Namespace("http://www.w3.org/1999/02/22-rdf-syntax-ns#");
var attributes:XMLList = XML(event.result).rdf::Description.rdf::value;
The previous code returns xxx for the following XML document:
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdf:Description>
<rdf:value>xxx</rdf:value>
</rdf:Description>
</rdf:RDF>
The following example shows an alternate way to get an element or attribute value when the declared rdf namespace
is specified on an element or attribute:
namespace rdf = "http://www.w3.org/1999/02/22-rdf-syntax-ns#";
use namespace rdf;
var attributes:XMLList = XML(event.result).rdf::Description.rdf::value;
The previous code also returns xxx for the following XML document:
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdf:Description>
<rdf:value>xxx</rdf:value>
</rdf:Description>
</rdf:RDF>
Handling web service results that contain .NET DataSets or DataTables
Web services written with the Microsoft .NET Framework can return special .NET DataSet or DataTable objects to the
client. A .NET web service provides a basic WSDL document without information about the type of data that it
manipulates. When the web service returns a DataSet or a DataTable, data type information is embedded in an XML
Schema element in the SOAP message, which specifies how the rest of the message must be processed. To best handle
results from this type of web service, you set the resultFormat property of a Flex WebService operation to object.
You can optionally set the WebService operation’s resultFormat property to e4x, but the XML and e4x formats are
inconvenient because you must navigate through the unusual structure of the response and implement workarounds
if you want to bind the data, for example, to a DataGrid control.
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When you set the resultFormat property of a Flex WebService operation to object, a DataTable or DataSet returned
from a .NET web service is automatically converted to an object with a Tables property, which contains a map of one
or more DataTable objects. Each DataTable object from the Tables map contains two properties: Columns and Rows.
The Rows property contains the data. The event.result object gets the following properties corresponding to DataSet
and DataTable properties in .NET. Arrays of DataSets or DataTables have the same structures described here, but are
nested in a top-level Array on the result object.
Property
Description
result.Tables
Map of table names to objects that contain table data.
result.Tables["someTable"].Columns
Array of column names in the order specified in the DataSet or
DataTable schema for the table.
result.Tables["someTable"].Rows
Array of objects that represent the data of each table row. For
example, {columnName1:value, columnName2:value,
columnName3:value}.
The following MXML application populates a DataGrid control with DataTable data returned from a .NET web
service.
<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns="*" xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical">
<mx:WebService
id="nwCL"
wsdl="http://localhost/data/CustomerList.asmx?wsdl"
result="onResult(event)"
fault="onFault(event)" />
<mx:Button label="Get Single DataTable" click="nwCL.getSingleDataTable()"/>
<mx:Button label="Get MultiTable DataSet" click="nwCL.getMultiTableDataSet()"/>
<mx:Panel id="dataPanel" width="100%" height="100%" title="Data Tables"/>
<mx:Script>
<![CDATA[
import
import
import
import
mx.controls.Alert;
mx.controls.DataGrid;
mx.rpc.events.FaultEvent;
mx.rpc.events.ResultEvent;
private function onResult(event:ResultEvent):void {
// A DataTable or DataSet returned from a .NET webservice is
// automatically converted to an object with a "Tables" property,
// which contains a map of one or more dataTables.
if (event.result.Tables != null)
{
// clean up panel from previous calls.
dataPanel.removeAllChildren();
for each (var table:Object in event.result.Tables)
{
displayTable(table);
}
// Alternatively, if a table's name is known beforehand,
// it can be accessed using this syntax:
var namedTable:Object = event.result.Tables.Customers;
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//displayTable(namedTable);
}
}
private function displayTable(tbl:Object):void {
var dg:DataGrid = new DataGrid();
dataPanel.addChild(dg);
// Each table object from the "Tables" map contains two properties:
// "Columns" and "Rows". "Rows" is where the data is, so we can set
// that as the dataProvider for a DataGrid.
dg.dataProvider = tbl.Rows;
}
private function onFault(event:FaultEvent):void {
Alert.show(event.fault.toString());
}
]]>
</mx:Script>
</mx:Application>
The following example shows the .NET C# class that is the backend web service implementation called by the
application; this class uses the Microsoft SQL Server Northwind sample database:
:
<%@ WebService Language="C#" Class="CustomerList" %>
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Web.Services.Description;
using System.Data;
using System.Data.SqlClient;
using System;
public class CustomerList : WebService {
[WebMethod]
public DataTable getSingleDataTable() {
string cnStr = "[Your_Database_Connection_String]";
string query = "SELECT TOP 10 * FROM Customers";
SqlConnection cn = new SqlConnection(cnStr);
cn.Open();
SqlDataAdapter adpt = new SqlDataAdapter(new SqlCommand(query, cn));
DataTable dt = new DataTable("Customers");
adpt.Fill(dt);
return dt;
}
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[WebMethod]
public DataSet getMultiTableDataSet() {
string cnStr = "[Your_Database_Connection_String]";
string query1 = "SELECT TOP 10 CustomerID, CompanyName FROM Customers";
string query2 = "SELECT TOP 10 OrderID, CustomerID, ShipCity,
ShipCountry FROM Orders";
SqlConnection cn = new SqlConnection(cnStr);
cn.Open();
SqlDataAdapter adpt = new SqlDataAdapter(new SqlCommand(query1, cn));
DataSet ds = new DataSet("TwoTableDataSet");
adpt.Fill(ds, "Customers");
adpt.SelectCommand = new SqlCommand(query2, cn);
adpt.Fill(ds, "Orders");
return ds;
}
}
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