fulltext
Bachelor Thesis Project
Cross-Platform Desktop Development
(JavaFX vs. Electron)
Author: Abeer Alkhars
Author: Wasan Mahmoud
Supervisor: Johan Hagelbäck
Semester: VT/HT 2016
Subject: Computer Science
Abstract
Today, there are many technologies available for developing cross-platform
desktop apps. JavaFX is a software platform based on the Java language. It has
a set of features that play a role in its success. On the other hand, Electron is a
new framework that allows developers to employ web technologies
(JavaScript, HTML, and CSS) to create cross-platform desktop applications.
This thesis describes and compares between these two frameworks. The
purpose of this report is to provide guidance in choosing the right technique
for a particular cross-platform desktop application. Simple cross-platform
desktop applications have been developed to compare both approaches as well
as find the advantages and disadvantages. The results show that both apps
satisfied the functional and nonfunctional requirements. Each framework
architecture has its own advantage in building particular apps. Both
frameworks have rich APIs as well as rich GUI components for building
desktop apps. Electron has good documentation and community help, but it
cannot be compared to JavaFX. The Electron app gives faster execution time
and less memory usage than JavaFX app. However, the implementation of
OOP concepts in Electron using JavaScript has some concerns in terms of
encapsulation and inheritance.
Keywords: cross-platform desktop development, Java, JavaFX, Electron,
performance, web technologies, object-oriented programming.
2
Preface
The bachelor degree project was performed at the department of Computer
Science at the Linnaeus University in Växjö. We want to thank our supervisor
Johan Hagelbäck for the meetings, supervision, and helpful feedback for this
project. Another thank goes to our families for their support and encouraging
during our study.
3
Contents
1
Introduction ________________________________________________7
1.1 Background __________________________________________ 7
1.1.1 Overview of Software development __________________ 7
1.1.2 Cross-platform development for desktops______________ 8
1.2 Previous Research_____________________________________ 8
1.3 Problem Formulation__________________________________ 10
1.4 Motivation__________________________________________ 10
1.5 Research Question____________________________________ 11
1.6 Scope/Limitation______________________________________11
1.7 Target Group_________________________________________11
1.8 Outline______________________________________________11
2 Framework Description _____________________________________13
2.1 JavaFX ___________________________________________ 13
2.1.1 JavaFX Framework ___________________________ 13
2.1.2 JavaFX Architecture___________________________ 13
2.1.3 The Programming Language of JavaFX____________ 14
2.1.4 JavaFX APIs and Features_______________________ 14
2.1.5 Summary____________________________________ 14
2.2 Electron___________________________________________15
2.2.1 Electron Framework ___________________________ 16
2.2.2 Electron Architecture __________________________ 16
2.2.3 The Programming Language of Electron____________19
2.2.4 Electron APIs and Features ______________________19
2.2.5 Summary_____________________________________20
3
Method_________________________________________________21
3.1 Criteria Used for Framework Comparison________________21
3.2 Implementation_____________________________________22
3.3 Software Comparison _______________________________ 23
3.4 Reliability and Validity_______________________________23
4
Implementation_________________________________________25
4.1 Software Overview_________________________________ 25
4.1.1 Software Description____________________________25
4.1.2 Software Requirements __________________________25
4.1.3 Software Design________________________________26
4.1.4 Software Use Cases_____________________________29
4.2 Software Development______________________________31
4.2.1 Technologies and Tools__________________________31
4.2.2 Software Architecture___________________________ 32
4.3 Software Comparison________________________________38
4.3.1 The Programming Language______________________38
4.3.2 The Database Implementation_____________________41
4.3.3 The Richness of Graphical User Interface___________ 42
4
4.3.4 The Availability of Native APIs___________________45
4.4 Performance Measuring_______________________________51
5
Results___________________________________________________53
5.1 Results of the Performance Measuring _____________________53
5.1.1 Execution Time________________________________ 53
5.1.2 Memory Usage_________________________________54
5.2 Results of Software Comparison __________________________56
6
Discussion_______________________________________________ 59
6.1 Initial Discussion______________________________________ 59
6.2 Discussion of Performance Test Results____________________ 59
6.3 Discussion of Software Comparison Results_________________60
7 Conclusion_______________________________________________ 63
7.1 Conclusion___________________________________________ 63
7.1.1 Answer to the Research Questions_________________63
7.1.2 Future Research _______________________________64
References_________________________________________________66
5
List of Figures
2.1 JavaFX architecture
2.2 Electron’s source code architecture
2.3 Electron multi-process architecture
2.4 Chromium sandbox
2.5 Electron sandbox
4.1 Software object model
4.2 Relational database model
4.3 Software GUI design
4.4 JavaFX app class diagram
4.5 JavaFX app structure
4.6 Screenshot of JavaFX app
4.7 Electron app architecture
4.8 Screenshot of Electron app
4.9 ListView design in JavaFX app
4.10 HTML5 table in Electron app
5.1 Execution time for CURD actions of Text Note in millisecond
5.2 Execution time for CURD actions of Photo Note in millisecond
5.3 Memory usage for CURD actions of Text Note in megabyte
5.4 Memory usage for CURD actions of Photo Note in megabyte
List of Tables
1.1
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
Research Questions
Execution time for CURD actions of Text Note in millisecond
Execution time for CURD actions of Photo Note in millisecond
Memory usage for CURD actions of Text Note in megabyte
Memory usage for CURD actions of Photo Note in megabyte
Results of the programming language
Results of the database
Results of the GUI
Results of the native APIs
6
1 Introduction
A desktop application is a software that runs on a single computer (laptop or
desktop) and is used to perform specific tasks. It has access to the computer’s
operating system and hardware resources, including access to the files and
folders on the user’s computer. When developing a desktop application, there
are three major operating systems the developer should consider (Mac,
Windows, and Linux). Each operating system has separate APIs and
programming environments which lets the developer to create the same
application more than once.
Cross platform development allows developers to build an application
once and have it run on different platforms. Such development process can
save time and helps reduce costs. JavaFX and Electron are two solutions for
cross-platform desktop development. Those frameworks differ in the way they
build the applications. JavaFX is a software platform based on the Java
language. While Electron uses Chromium and Node.js to build cross-platform
desktop applications with web languages (HTML5, CSS, and JavaScript). This
thesis compares these two different development technologies and shows their
advantages and disadvantages.
1.1 Background
This section contains overview of Software development and Cross-platform
development for desktops.
1.1.1 Overview of Software development
For last 20 years, most of the software was available as desktop apps. Any user
wants to use an app, he or she would need to check the system requirements
and make sure that the software can run on their operating systems.
However, over the time, the web apps begin to grow rapidly. The
improvements in the internet speeds and web browsers also influence on the
need for desktop apps. Technologies like AJAX has provided a way to build
software as web apps. They did not require the users the download or install
anything. As a result, may software companies began to move to online.
Google is one of the businesses that are leading this trend. Google maps began
as a C++ desktop program designed by Lars and Jens Eilstrup Rasmussen. In
October 2004, the company was earned by Google, which converted it into a
web application [7].
Recently, the mobile apps have appeared, and the industry changed again.
These mobile apps are used today for different tasks such as calling, sending
text messages, surfing the internet, playing games and work. As a result of
these changes in the industry, software developers found themselves among a
number of computing platforms and might increase in the future. Therefore, it
has become a need for creating apps run on multi-platforms.
7
There might be someone argues that desktop apps are dead. However,
desktop apps are still one of the computing platforms that are used today. The
main benefit of desktop apps is obvious. Desktop apps are installed on the
computers which mean fewer restrictions and enhanced privileges. Desktop
apps do not rely on the internet connection which can increase the security of
the apps. At the same time, they can still work even if the internet connection
is not available [12].
1.1.2 Cross-platform development for desktops
Cross-platform desktop development refers to the creation of applications that
are compatible with multiple operating systems for desktop such as Windows,
Mac, and Linux. Cross-platform desktop development is not a new concept.
There has been a plethora of options for accomplishing this over the decades.
Flash Air, JavaFX, and Silverlight are options for cross-platform development
[8]. Java is considered one of the oldest approaches to cross-platform desktop
development. It is an object-oriented language that has a rich set of APIs for
building graphical user interface (GUI) that look native such as AWT, Swing,
and JavaFX [1]. Usually, developers with a background in programming
languages like C, C++, C#, and Java could develop cross-platform desktop
applications.
For a long time, web developers who wanted to build desktop applications
would need to learn a new language alongside a framework, and this would be
a barrier in developing desktop applications. Today, there are frameworks
available for web developers to create cross-platform desktop apps. Electron is
one of the newest frameworks that allows developers to build native desktop
apps with popular web technologies: JavaScript, HTML5, and CSS. With
Electron, web developers can use their existing skills to build applications that
have many of the capabilities of a native desktop application. Electron has
become very popular since its release and used by companies like Microsoft,
Facebook, Slack, and Docker [2].
1.2 Previous research
Cross-Platform development has been a subject of many types of research.
Papers, articles, and books have been already shown that with cross-platform
frameworks, it has become possible for developers to create applications run
on multi-platforms. According to Xanthopoulos et al, there is a currently a
trend to develop cross-platform apps. The reason of this, is that native
development requires severe constraints, such as the use of different
development environments, technologies, and APIs for each platform, leading
to a waste of development time and effort, and an increased maintenance cost
[4].
8
During the literature review, we found that most of these papers discuss
different aspects of cross-platform development for mobile, while we noticed
that there is a lack of the scientific research that about cross-platform
development for the desktop. Electron in particular has not been a target in any
research since it is still new technology in the market.
In the paper “A comparative analysis of cross-platform development
approaches for mobile applications” written by Xanthopoulos et al, the authors
discuss the most important cross-platform app types, which are the web,
hybrid, interpreted and generated apps. Interpreted apps which can be
developed using language like Java have native user interfaces, and the
application logic is implemented independently. Consequently, the
performance that is achieved by these apps is medium compared to native apps,
considering the extra time needed to interpret the application logic and the
APIs to access the hardware components. Another point that paper mentioned
is that interpreted apps have a limitation on hardware and data access. Hybrid
apps, on the other hand, simulate the look and feel of a native application. The
main advantage of this approach is having one code base run in multi-platforms
and using widely used web development technologies. The paper states that
Hybrid apps have a medium performance as perceived by the end users
compared to native apps. Also, the hardware and data access to the underlying
platform is limited [4].
In the article "Frameworks & Tools to Develop Cross-platform Desktop
App – The Best Of,” Ashutosh discusses the importance of cross-platform
development. The author also compares nine frameworks and toolkits for
cross-platform desktop applications and tries to find the advantages and the
disadvantages. The frameworks that have been compared in the article are
Haxe, Electron, NW.js, 8th, B4J, Kivy, Xojo, Enyo, and WINDEV Express.
The author mentions that the advantage of using Electron is that it allows
developers to focus on the core functionality of the applications by taking care
of the hard part. Also, Electron provides many features for desktop applications
such as auto-update, crash reporter, and installer creator. However, the
disadvantage of Electron is that it does not support MVC pattern and is not as
feature-rich as NW.js [3].
In the article “Cross-Platform Development For Desktops: Choosing The
Right Technology,” the author tries to outline the advantages and
disadvantages of the most common technologies for cross-platform desktop
development. The technologies that are discussed are Java, Adobe AIR, Haxe,
QT, and JavaScript-based solutions such as NW.js, Electron, and CEF. The
author mentions that Java has an enormous amount of third-party libraries that
solve different tasks, with focusing on data processing algorithms. Java also
supports multithreading programming. The author lists a set of disadvantages
for Java development such that Java virtual machine must be available on
computers that run the app. Java has weak support for code portability as well
as the GUI, but this issue has been fixed after releasing JavaFX. In addition,
9
the author finds that using JavaScript for cross-platform development is a good
choice because JavaScript is currently the most popular language. It has an
enormous amount of libraries on the Web, which can be used in desktop apps.
However, the author argues that cross-platform desktop development with
JavaScript is a rather young concept, and should not be selected if the app
contains complex algorithms of data processing [5].
1.3 Problem Formulation
The developers that want to build the same application for different platforms,
use separate APIs and programming environments for every platform. This
increases the cost of development and production time. To avoid this problem,
the developers need to create an application only once and then distribute it on
all platforms by using cross-platform solution. This solution allows having
only one codebase and just one programming environment. That would
possibly lead to reduce costs and time required to develop applications [25].
JavaFX is the newest GUI API of Java that allows this capability with a
degree of success. Also, Electron is a new framework that allows developers
to utilize web technologies (JavaScript, HTML, and CSS) to create crossplatform desktop applications. The benefit of using Electron over JavaFX is
that web developers now can create desktop apps without having to learn Java
or any other language.
It is important for developers to know how to approach the solutions in
multi-platform in two very distinct technologies (JavaFX & Electron). It is
expected to find a difference between both technologies. Even though both
technologies have the same functionality, but they are diverse. JavaFX is based
on object-oriented language, while Electron is based on JavaScript which is a
scripting language. Therefore, they do not perform their functions in the same
way.
1.4 Motivation
Developing a cross-platform application is not a simple process. The
development requires careful consideration of many aspects that are necessary
for a successful product. The programmer should pay enough attention in
choosing proper cross-platform technology at the beginning; because it is
nearly impossible to replace the architecture in future. However, it is important
to mention that the study does not nominate the technology which is better
overall. The purpose is to serve the programmers in choosing the right
technologies based on their needs.
10
1.5
Research Question
The research questions for this thesis are the following:
RQ1
RQ2
How does the performance of the cross-platform desktop apps differ
when developed in Electron compared to JavaFX?
What are the benefits and drawbacks of both technologies
(Electron & JavaFX) for cross-platform desktop development?
Table 1.1: The Research Question.
1.6
Scope/Limitation
This study has the following set of limitations:
● Theoretical part: it focuses on two cross-platform desktop frameworks
JavaFX and Electron. It also gives a general background of related
frameworks, but does not go into details. Each framework has been
studied to discover the differences and identify all important aspects.
● Implementation part: cross-platform desktop applications have been
developed using Electron and JavaFX. The purpose is to compare both
approaches as well as find the advantages and disadvantages. The
comparison has been limited on the performance in terms of memory
usage and execution time, the programming language, database,
availability of APIs and richness of GUI.
1.7
Target Group
The potential target groups for this study are developers or IT students who
want to learn about cross-platform desktop development, more especially
about JavaFX and Electron framework. The result of this study may bring more
insight for them regarding the efforts of choosing the right technique for crossplatform desktop development.
1.8
Outline
The rest of the report is divided into the following chapters:
Description of the frameworks: in this chapter JavaFX and Electron
framework will be described and detailed.
Method: this chapter explains the scientific approach that is used to answer
the research questions.
Implementation: this chapter presents the implementation of the applications.
It contains the following sections:
11
● Section 1: software overview. This section includes the software
description, requirements, design, and use cases.
● Section 2: software development. This includes an overview of the
applications including software architecture.
● Section 3: software comparison. The comparison of both applications
includes the programming language, database, richness of GUI, and
availability of APIs.
● Section 4: performance measuring.
Result: this chapter presents the performance as well as finds the differences
of using both technologies.
Discussion: this chapter discusses the findings of this thesis and gives general
answers to the research questions.
Conclusion: this chapter gives a summary of the whole thesis, formal
answers to the research questions and some information about possible future
research.
12
2
Framework Description
This section contains the theoretical part of this thesis. It provides a
background includes the characteristics and features of the chosen frameworks.
2.1
JavaFX
This section describes JavaFX Framework, its architecture, the programming
language that JavaFX uses, and JavaFX features.
2.1.1 JavaFX Framework
JavaFX is a software platform for building desktop applications that can run
across different devices. It is developed by Sun Microsystems and it was
released to the public in December 2008 [26]. JavaFX is intended to replace
Swing as the standard GUI library for Java SE. JavaFX includes the graphics,
layout containers, images, and media. It allows developers to design, create,
test, debug, and deploy rich client applications that behave consistently across
diverse platforms [18].
Java 8 offers support to deploy a JavaFX application as a native app. In this
case, the JRE will be packaged with the application. A native executable file
will be created and executed without the need for Java on the client system.
Additional information, like metadata or application icons, can also be defined
for the native app. The bin folder of the JDK includes the JavaFX packager
executable that must be used to create such a bundled application. There are
plugins for Maven, Ant, and Gradle available to support these features
automatically [21].
2.1.2
JavaFX Architecture
The following architecture diagram shows the architecture of JavaFX APIs and
the components that support JavaFX APIs.
13
Figure 2.1: JavaFX Architecture [18].
JavaFX is constructed on a layered architecture of components which supports
the user interface. As it is shown in figure 2.2, the top layer provides a complete
set of public APIs that provide flexibility to build rich client applications. The
top layer also provides Scene Graph which is a hierarchical tree of nodes that
include all the elements in an application UI and their relationships. Each node
has a single parent and zero or more children. Also, it has an ID, style class,
and bounding volume, effects, transforms, opacity, event handlers, and an
application-specific state. The layered architecture by the APIs and scene
graph is especially effective when the UI includes video, audio, graphics, and
animation, which is typical of JavaFX applications.
In the layers below, the graphics (Prism and Quantum Toolkit), Glass,
web, and media components provide improvements that reduce coding time.
The Java Virtual Machine is layered in the bottom. It provides JRE to
execute JavaFX applications. JVM handles application tasks such as object and
stack management, loading and storing variables, branching, arithmetic,
method invocation and return, type conversions, exception throwing, and
concurrency [18].
2.1.3
The Programming language of JavaFX
JavaFX is based on Java language which was also developed by Sun. Java is
an object-oriented programming language which includes an execution engine
called a virtual machine, a compiler and set of APIs for the application
development. It is also not specific to any processor or operating system [16].
2.1.4
Features of JavaFX
The latest releases have the following features:
● FXML and Scene Builder. JavaFX Scene Builder allows
designing JavaFX application user interfaces quickly by drag and
drop components to a work area. The result is a separate FXML
file from the application's logic.
● 3D Graphics Features. JavaFX supports Shape such as Box,
Cylinder, MeshView, and Sphere subclasses, SubScene,
Material, PickResult, AmbientLight, and PointLight.
● CSS. It is used to style the look and feel of JavaFX applications.
● Canvas API. The Canvas API enables drawing directly on
JavaFX scene.
14
● Rich text support. JavaFX includes bi-directional text and
complex text scripts, such as Thai and Hindu in controls, and
multi-line, multi-style text in text nodes.
● Self-contained application deployment model. Self-contained
application packages have the application resources and a private
copy of the Java and JavaFX runtimes.
● WebView. This component uses WebKitHTML technology to
make it possible to render web pages within a JavaFX
application. WebView supports JavaScript, which is called in the
web page from Java APIs. WebView also Support HTML5
features, including Web Sockets, Web Workers, and Web Fonts.
● Hardware-accelerated graphics pipeline. JavaFX offers
smooth graphics that render quickly into the graphics rendering
pipeline (Prism) when it is used with a supported graphics card
or graphics processing unit (GPU).
● High-performance media engine. The playback of web
multimedia content is supported by the media pipeline which
provides a high-performance media engine.
● Swing interoperability. Existing Swing applications can be
updated by using JavaFX features, such as embedded Web
content and rich graphics media playback.
● Java Public APIs for JavaFX Features. The developers exploit
the powerful Java features, such as annotations, generics, and
multithreading [19].
2.1.5 Summary
Sun Microsystems provided different sets of Java APIs for graphics
programming and tried to develop those APIs to make it easier to create Java
applications. One of these was JavaFX, which is used with Java to allow
developers to build much more complex UIs that could further contain
advanced APIs more than the others.
2.2
Electron
This section is about Electron framework. It describes Electron architecture,
the programming language that Electron uses, and Electron’s features and
APIs.
15
2.2.1
Electron Framework
Electron is a framework that allows developers to create cross-platform
desktop applications with HTML5, CSS, and JavaScript. It is an open source
project started by Cheng Zhao (a.k.a. zcbenz), an engineer at Github. Electron
is the foundation for Atom, a cross-platform text editor by Github built with
web technologies. Although it was released in November 2013, it has become
very popular and is used by a number of large businesses for their applications.
Electron is not only used in Atom but also is used in the desktop clients of a
chat application called Slack [9].
2.2.2
Electron architecture
Electron combines Chromium and Node.js into a single runtime to provide
cross-platform desktop applications. Electron can be seen as a minimum
browser with the ability to interact with the operating system, and this browser
is a part of the application packaging. With Electron, the developers can forget
about any problem of cross-platform compatibility either between the
operating system and browser. They can be sure everyone who uses the
application has the same chromium version with the same Node.js version
regardless of user’ computer [2].
The following diagram shows the architecture of Electron.
Figure 2.2: Electron’s source code architecture [9].
By looking at an overview, the architecture of Electron shows a clean
separation of the Chromium source code to the application. The advantages of
16
this are that it makes it easier to upgrade the Chromium component, and it also
means that compiling Electron from the source code becomes a bit simpler.
The Atom component is the C++ source code for the shell. Inside of it,
there are four distinct parts of Electron components. Each has specific
responsibility in building the Electron application. Then, there is also the
source code for Chromium which the Atom Shell uses to combine Chromium
with Node.js.
Chromium and Node are both wildly popular platforms, and both have
been used independently to create ambitious applications. Electron brings the
two platforms together to allow developers to use JavaScript to build an
entirely new class of applications [9].
Node.js
Node.js is a JavaScript platform built on Google chrome’s JavaScript V8
Engine. It provides a runtime environment for developing server side
applications using JavaScript and APIs for accessing the file system, creating
web server and loading code from the external module.
Node is open source and is used by thousands of developers around the
world. With Node.js, it is possible for developers to share and update code as
well as use over 250,000 npm packages. Node.js can be seen as a pure web
applications framework, but the truth is that Node.js can be used for desktop
applications as well. Electron is an example of the frameworks that use Node.js
for creating cross-platform desktop applications [9].
Chromium browser
Chromium browser is an open-source version of Google’s Chrome web
browser. They share most of the code and features with some differences in
features and different licensing. Chromium handles rendering web pages in an
independent process, loading CSS styling and executing JavaScript codes [11].
1- Electron’s multi-process architecture
Electron applications inherit chromium’s multi-process model. Electron
applications, mainly consist of two types of processes: the main process and
zero or more renderer processes. Each process plays a different role in the
application. The Main Process is responsible for creating and controlling the
lifecycle of the app. It is also responsible for communicating with native
operating system APIs. The Renderer Process loads web pages to display a
graphical user interface. Each process takes advantage of Chromium’s multiprocess architecture and runs on its own thread. Electron also includes the
ability to facilitate communication between processes in order to allow the
renderer process to communicate with the main process in the event that they
need [2].
17
Figure 2.3: Electron’s multi-process architecture.
2- Electron sandbox
Chromium encapsulates web pages in a sandbox environment. The only
resources that are freely used in the pages are the CPU cycle and memory.
Thus, the web pages are completely isolated; they cannot access the file system
or
hook
into
the
operating
system
APIs
[12].
Figure 2.4: Chromium sandbox [12].
It is important to mention that Electron applications are out of the sandbox.
Electron developers have disabled the chromium sandbox to provide a runtime
environment that has access to operating system APIs, node.js APIs, and third
party modules. Thus, Electron applications have unfiltered access to the
operating system [12].
18
Figure 2.5: Electron sandbox [12].
2.2.3 The Programming language of Electron
As mentioned earlier, Electron uses web technologies JavaScript, HTML5 and
CSS for developing desktop applications. These technologies are the basis
when building web pages. Electron uses web pages for creating the graphical
user interface of the app. The structure of a page is created using HTML5,
while the visual layout is made using CSS. JavaScript, which is a client-side
programming language, can be used together with these technologies to make
a web page dynamic [2].
2.2.4
Electron APIs and Features
In addition to the rich APIs of Node.js and HTML5, Electron has come up with
a useful set of APIs and features for building desktop applications:
• Create application windows, each with their own JavaScript context.
• Desktop integration through the shell and screen APIs.
• Tracking the power status of the computer.
• Monitors the power state change.
• Creating tray applications.
• Copying and pasting from clipboard.
• Creating menus and menu items.
• Adding global keyboard shortcuts to the application.
• Updating the application’s code automatically through app updates.
• Crash reporting for when the application crashes.
• Customizing Dock menu item.
• Operating System Notifications.
• Creating Window Installers.
• Debugging and profiling.
• Showing native system dialog.
19
As can be seen in the list above, there are a lot of features that Electron offers,
and that is not the complete list of features available in the framework. In
particular, the crash reporting feature is unique to Electron. Additional to that,
Electron provides dedicated tools for application testing and debugging,
called Spectron and Devtron [10].
2.2.5 Summary
In this section, we introduced Electron and we discussed how it allows
developers to build a desktop application with web technologies. We found
that chromium and Node.js are the main technologies that are used to build
Electron, which allow developers to build applications that can both access the
file system as well as render a user interface and use Web APIs. We also
discussed the roles and responsibilities of the two types of processes in the
Electron applications. Finally, we presented some of the APIs and features that
Electron provides for desktop applications such as menus, try, dialogs, battery
status and power settings, and more.
20
3
Method
This section describes the method that has been used in this thesis to answer
the research questions. After we explored the characteristics and features of
each framework, the work was divided into three different parts. The first part,
selecting comparison criteria, refers to the aspects that comparison was limited
by. The second part, implementation, refers to the cross-platform desktop
applications that were developed. The third part, software comparison, refers
to investigate the differences, make analysis, and do a comparison.
3.1
Criteria Used for Framework Comparison
This section contains some details about the criteria that have been chosen for
the framework comparison.
The criteria purposes to cover the most common requirements in crossplatform developments. The selection of these criteria was based on and have
been inspired by various sources. We have started by reviewing different
resources to find the common requirements in software developments [5, 23,
24]. After that, we have summarized the common requirements that we found
on those papers in an initial list. Then the final set of criteria has been drawn
after a discussion with our supervisor Johan Hagelbäck.
1- The programming language
The programming language that is offered for implementing the application.
The aspects that are considered in the comparison are:
● Object-oriented programming concepts. Specifically, (encapsulation
and inheritance).
● Project structure/ organize projects and code.
● Documentation, guidelines, and community help.
2Database
Databases for implementing client side storage.
3Richness of GUI
The components and tools that are provided for building rich graphical user
interface such as the availability of controls, drag and drop components tool,
data binding, data grid, etc.
21
4The availability of APIs
The application programming interfaces that are provided for building the
application and getting native access to the operating system. The list below
presents the APIs that are considered in the comparison:
● Using global shortcut (Accelerator).
● Accessing file system.
● Copying and pasting from clipboard.
● Opening external links in the default browser.
● Showing native system dialog.
5- Performance:
The performance is one of the quality attributes that are important when
developing software [15]. With such a large number of quality attributes to
study, it is necessary to limit research to a relevant subset. The performance
was chosen for two reasons. First, the performance which is achieved by crossplatform frameworks is considered an issue in many cases since these
frameworks cannot offer the same power and speed of native development [4].
Second, we believe that the performance is necessary for all types of
applications. However, it can be particularly interesting for rich desktop
applications which usually demand more system resources.
The performance that will be measured is the performance of the developed
applications in terms of memory usage and execution time. In this experiment
a personal computer with the following specification is used:
● Windows 10 pro 64 bytes.
● Intel core i5-2520M 2.5GHz processor.
● SATA HDD with 320GB.
● 4096MB RAM Memory.
● Intel HD Graphics 3000
3.2
Implementation
A simple note desktop application has been chosen for the implementation.
The choice of this particular application was made due to its applicability to
cover the selected criteria for the comparison. The application can access
native operating system APIs and be based on object-oriented programming.
It can also show how building a rich graphical user interface can be achieved.
The application was not purposed to replace an existing application or to
be deployed. The application was developed to create a proof of cross-platform
development concept in JavaFX and Electron and to clarify the strengths and
22
weaknesses of these frameworks based on the differences that were found in
the implementation.
After specifying the requirements of the application, two functionally
equivalent cross-platform desktop applications were built using JavaFX and
Electron. Due to the fact that the application is not so large and the
requirements are very well understood, the development process was
performed using the Waterfall model which is simple and easy to understand
and can be used in such situations. More details about the implementation are
presented in the following chapter.
3.3
Software Comparison
After identifying which attributes to compare with the chosen cross-platform
desktop frameworks and developing the apps, a qualitative comparison of both
applications was performed. The reason for doing a comparison is to find the
advantages and disadvantages of the technologies. That was achieved by an
analysis of each application. After having identified all interesting differences,
each frameworks' corresponding attributes were mapped down into a table in
order to provide a good overview for the comparison. Also, a quantitative study
was performed based on measuring the performance of the apps to find how
the performance differs between the used technologies.
3.4
Reliability and Validity
One reliability threat is that we are biased towards OO programming paradigm
more than the others. In addition to that, we have no previous experience in
Electron while we have used JavaFX in several projects. To reduce this gap
and produce much more reliable results, we will follow the official
documentations and the guidelines of these frameworks during the
implementation. Also, we will narrow the comparison on the selected criteria.
In this way, we will increase the validity since a smaller span of information
will be captured, instead of a broader range of data. The reason of choosing
these criteria is mentioned in the previous section 3.1. However, there will be
another validity threat when we analyze the advantages and the drawbacks of
the frameworks based only on the limited features that are implemented in the
applications. So, it will be unfair to judge the frameworks depending on just
used features while there are lots of other features for both frameworks.
Another validity threat regards the comparison of object oriented
principles. It might be unfair to compare two different programming paradigms
(Java and JavaScript). However, the comparison will not nominate which
language is the best. It will just show how each language can apply these
concepts and gather the benefits.
23
Both technologies are tested on appropriate tools to measure memory usage
and execution time. Each measurement is conducted more than once for each
action in both applications, to minimize the effect of measurement error. The
time measurement does not include the time that is used to print text to the
console or any unrequired operation. That to reduce the mistakes in the
execution time measurements during the experiments. To further increase
reliability, it is possible to search for other’s work, thesis, or blog and see if
their results are identical to what is said about those frameworks.
Performance measurements for both technicians are done on the same
computer. That could probably be considered as a good indicator of validity,
but it is not enough, the validity threat may happen because of the type and
efficiency of the chosen computer and repeating the same experiments using
different computers may lead to variation in the results.
Additionally, using different tools to measure the performance for JavaFX
and Electron can affect the validity but not the reliability. The reliability for
each tool is depending on the tool itself. We can make sure of the consistency
of the measure by getting nearly the same result through repeated inquiry
process. If there is no reliability, we can change the measurement tool. But the
validity threat may still exist as long as we use different tools. Although these
tools are used for the same purpose, but each one has its own way of measuring.
24
4.
Implementation
Implementation actually means to practice a plan, to design and to model to
bring something into an action. So, this chapter will contain the detailed
specifications related to the implementation.
4.1
Software Overview:
This section includes the software description, requirements, design, and use
cases.
4.1.1
Software Description
“Simple Note” is a desktop application that enables the user to save texts,
images, and links. This application presents the Notes in the form of Text and
Photo Notes. Text Note allows the user to add a title, text, and a link from the
browser. Photo Note is more related to an image. It allows to add a title, text,
link, and images. The user can perform CRUD (Create, Read, Update, and
Delete) operations on the Text and Photo Notes and the data is saved in a
persistent database.
The application can contain only one type of Note: to add, text, image,
and a link, but as the application is developed to manage different aspects such
as inherence, so there was a very much need to design the application in this
particular way. The implementation in section 3.2 provides the purpose of the
application.
4.1.2 Software Requirements
The first stage contains functional and non-functional requirements, which are
as follows:
1Functional Requirements
Following are the functional requirements that define the functionality of the
software:
• The user shall be able to add new Text/Photo Note either by clicking
on a button or by using a particular shortcut.
• The user shall be able to read the Text/Photo Note content.
• The user shall be able to update the Text/Photo Note content.
• The user shall be able to delete the Text/Photo Note.
• The user shall be able to add the image file in the Photo Note.
• The user shall be able to copy/ paste the text of the Text/Photo Note by
clicking on Copy/Paste Button.
25
•
•
•
The user shall be able to open the added link in the default browser.
The application can be able to show an error dialog when opening
invalid URL.
The application shall store the Text/Photo Notes in a database.
2Non-functional requirements
The following are the non-functional requirements that define the constraints
on the software development:
• The application shall be developed in JavaFX and in Electron
framework.
• The application shall be supported by inheritance and encapsulation
principle in an object-oriented programming.
• The application shall contain rich graphical interface.
4.1.3
Software Design
Software design was the second stage in the software development. During the
design the attempt was to meet all the software requirements. So, the work was
divided in two parts:
1. Object-oriented and database design refers to identifying the objects,
visualizing them by creating an object model, and describing how the
objects would be stored in the database.
2. GUI design which obviously refers to design a suitable interface for the
application.
1Object-oriented and database design
As reviewed from the requirements specification and software description,
Text Note and Photo Note are the required objects for this software. The Text
Note contains title, text, and link attribute. While the Photo Note inherits the
same set of properties and adds a new attribute, which is an image. Such type
of inheritance is known as strict inheritance. A single inheritance concept is
also achieved. The Text Note is extended to Photo Note. So, the Text Note is
a parent of Photo Note and the Photo Note is a child of Text Note. The diagram
below shows the object model design.
26
Figure 4.1 Software object model.
This diagram shows that the design encapsulates the object’s attributes from
direct access. These attributes are private and only can be processed by calling
get and set methods.
After specifying the object model, the design of the database is managed.
Relational database is selected to develop the model due to its ease and
flexibility.
After the review on the object model, we found that it is possible to apply
generalization and specialization database model. This design could slowdown the queries and make them more complex that could affect the app
performance. Therefore, the database was designed to have two tables; one for
Text Note and the other one for Photo Note. Each note would be stored in its
corresponding table in the database. The figure below shows the relational
database model of the app.
27
Figure 4.2: Relational database model.
1GUI design
After specifying the object-oriented and database design that would be
followed in the implementation, our task was to find a suitable graphical user
interface design for the application. Disregarding the look and feel of UI, the
attempt was to design an interface that included complex components. This
was to satisfy the non-functional requirement which is related to the GUI.
During the design, the focus was on how the application can get the note’s
properties and how it can be displayed. The interface was designed to have two
different forms for adding a new Text/Photo Note. This form contains
TextArea, TextFields, Drag and Drop, Buttons, etc. Also, two different area
were designed to display the notes on the screen. Each contains a list that
includes Labels, Buttons, and Images. Adding this number of components in
this simple application is required to find out, how each framework can build
such a rich interface as well as to gather the differences. The figure below
shows a prototype of GUI design.
28
Figure 4.3: Software GUI design.
4.1.4
Software Use Cases
This section contains the use cases for Simple Note application:
1-
Text note use cases
● Create Text Note:
1. The use case begins when the user clicks on ‘plus’ icon in the Text
Note panel or press Ctrl + Shift +A.
2. The application opens a form that contains title, link TextField and
TextArea for the Text Note.
3. The user writes the title, link, and text and then clicks Save.
4. The application saves the new note in the database.
29
5.
The application refreshes the Text Note panel to show the added
notes.
● Read Text Note:
1. All the Text Notes are available in the Text Notes panel.
2. The user clicks on a specific note in the Text Notes panel.
3. The application opens a Text Note form that contains the title, link,
and the text of the Text note.
● Update Text Note:
1. The use case begins when the user clicks on a specific note in the
Text Notes panel.
2. The application opens a Text Note form that contains the title, link,
and the text of the Note.
3. The user updates the title, link, and text and then clicks on ‘Save’
button.
4. The application updates the Text Note in the database.
5. The application refreshes the Text Note panel to show the updated
note.
● Delete Text Note:
1. The user clicks on Trash icon that is next to the note in the Text
Note panel.
2. The application deletes the Text Note from the database.
3. The application deletes the note from the Text Note panel.
2- Photo Note use cases
• Create Photo Note:
1. The use case begins when the user clicks on ‘plus’ icon in the Photo
Note panel or presses Ctrl + Shift + B.
2. The application opens a form that contains title, link TextField,
TextArea for adding text and drag and drop area for adding an image.
3. The user can write the title, link, text, and drag and drop the image in
in drop image area, then clicks on ‘Save’ button.
4. The application refreshes the Photo Note panel to show the added photo
notes.
● Read Photo Note:
1. All the Photo Notes are available in the Photo Note panel.
2. The user clicks on a specific note in the Photo Note panel.
30
3.
The application opens a photo Note a form that contains the title, link,
text, and the image of the note.
● Update Photo Note:
1. The use case begins when the user clicks on a specific Note in the Photo
Note panel.
2. The application opens a Photo Note form that contains the title, link,
text, and the image of the note.
3. The user updates the title, link, text, and the image and then clicks
‘save’ button.
4. The application updates the Photo Note in the database.
5. The application refreshes the Photo Note panel to show the updated
note.
● Delete Photo Note:
1. The user clicks on Trash icon located at the left side of the screen next
to the Photo Note in the Photo Note panel.
2. The application deletes the Photo Note from the database.
3. The application refreshes the Photo Note panel.
3- Copy and paste note from clipboard use cases
1. The use case begins when the user clicks on ‘Copy’ button in Text Note
or Photo Note.
2. The application copies the content of the TextArea in the clipboard.
3. The user clicks on ‘paste’ button in the Text Note or Photo Note.
4. The application pastes the text in the TextArea from the clipboard.
4- Open external URL
1. The use case begins when the user clicks on the open link button in the
Text Note or Photo Note.
2. The application opens the URL in the default browser.
3. The application shows an error dialog in the case of opening an invalid
URL.
4.2 Software Development
This section presents the technologies and tools that were used in the
development as well as the architecture of the developed apps.
4.2.1 Technologies and Tools
This section presents the tools that are used to build the application.
31
● For JavaFX app, the following tools were used:
1. Java SE 8.
2. JavaFX 8.
3. SQLite database.
4. NetBeans IDE.
5. JavaFX Scene Builder.
● For Electron app, the following tools were used:
1. Electron framework version 0.0.1.
2. Web SQL Database/SQLite.
3. Atom IDE.
4. JQuery and bootstrap library.
4.2.2 Software Architecture
This section provides an overview of the implemented applications that
include software diagram, description of software architecture and final
GUI of application.
1- JavaFX version
The application is designed by following the Model-View-Controller (MVC)
pattern. It consists of three parts: the Model, the View, and the Controller. The
Model represents the data of the application and the business rules to
manipulate the data. The View corresponds to elements of the user interface.
The Controller manages the communication between the Model and the View.
The diagram below shows the class diagram of the JavaFX application.
32
Figure 4.4: JavaFX application class diagram.
The Model consists of the Text and Photo Note classes. It also interacts with
the database to perform CRUD operations in the database.
The View consists of FXML files. The main file is fxmlDocument which
is associated with a Controller class by specifying the fx: controller attribute.
The following code is a part of fxmlDocument:
<AnchorPane id="AnchorPane" prefHeight="600.0" prefWidth="900.0"
xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1"
fx:controller="controller.FxDocumentController">.
The above code shows that the AnchorPane is the top node in the FXML file.
It has all the required children to build the user interface. Each child has a fxid tag to be accessed from the Controller class. The properties of the child like
style sheets are also configured in this FXML file.
The Controller contains classes include variables that are marked with
@FXML. The @FXML tag defines objects and event handlers such as
ActionEvent and MouseEvent. This manages the requested data from the
Model and the required components from the View to handles this data.
33
Figure 4.5 JavaFX Application Structure.
The figure above shows how JavaFX executes the application. The app starts
by executing the mainSimpleNote class which invokes the FXML Loader.
The FXML Loader object parses the fxmlDocument file, instantiates the
objects, and creates the scene graph root. After the scene graph root has been
completely
loaded,
the
FXML
Loader
instantiates
the
FxDocumentController class and invokes its initialize () method. The
following is the code of the mainSimpleNote class of JavaFX app:
public class mainSimpleNote extends Application {
@Override
public void start (Stage stage) {
//Set up FXMLloader
FXMLLoader loader = new FXMLLoader( );
loader.setLocation(getClass().getResource("/fxml/FXMLDocument.fxml"));
// read the FXML file and convert its content to a Parent object
Parent root = loader.load();
// construct the scene
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show()}
The code above shows how the FXMLLoader class loads the FXML file and
returns a root object. This object is then added to the starting point
for constructing the application and the final result will be displayed as shown
in the following screenshot:
34
Figure 4.6 Screenshot of JavaFX app.
2- Electron version
Electron application consists of three important parts. The main process,
renderer process, and package.json file. The diagram below shows the
structure of the Electron application:
35
Figure 4.7 Electron application architecture.
The app starts by reading the package.json. The package.json file has Name,
Main, and Version properties. Name contains the name of the application.
Main contains the name of the main script which will be executed by Electron
when the application starts. Version contains the version number of the
application.
The structure of the package.json file is as follows:
{
"name": "SimpleNoteApplication",
"main": "main.js",
"version": "0.0.1",
}
Electron executes the main process which is main.js file that is defined
in the package.json. Once the main process is executed, it creates its
renderer process. The renderer process contains index.html, style.css, and
JavaScript files. The javaScript files include the Object Model of the app. It
also interacts with the client database to perform CRUD operations.
The index.html file is an HTML5 file refers the CSS file and loads the
JavaScript files to execute code in this process.
36
Hence executing main.js file does not provide UI of the app. The UI is
created by using the specific Electron API called BrowserWindow. Then the
BrowserWindow module loads the index.html to display the UI of the app.
When the BrowserWindow instance is destroyed, the renderer process is
terminated. The main process and the renderer process can also
communicate with each other using IPC module. The IPC module allows to
send and receive messages between the sender and receiver. A part of the
main.js code is the following:
const electron = require('electron') // load the electron module from NPM
const app = electron.app // Module to control application life.
const BrowserWindow = electron.BrowserWindow // Module to create native
browser window.
let mainWindow
function createWindow () {
// Create the browser window.
mainWindow = new BrowserWindow({width: 950, height: 700})
// and load the index.html of the app.
mainWindow.loadURL(`file://${__dirname}/renderer/index.html`)
// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
app.on('ready', createWindow)
// Emitted when the window is closed.
mainWindow.on('closed', function () {
mainWindow = null })}
The ‘ready’ method in the code above has a callback function known as
“createWindow”. This function defines a BrowserWindow and sets its initial
size. Then, the index.html file is loaded on it to show GUI of the app.
37
Figure 4.8 screenshot of Electron application.
4.3
Software Comparison
This section compares the implementation of JavaFX and Electron apps.
During the development, the objective addressed all the functional and nonfunctional requirements. First, the object-oriented design was implemented in
JavaFX and Electron application. Then, the databases were created. After that,
the GUI of the apps was also built. Finally, the native features of the apps were
added.
4.3.1
The Programming Language
This section compares the apps based on the following aspects:
1- Object-oriented programming
Starting from OOP, Java is the class based object-oriented language. It has a
standard way to implement OOP based on the concept of classes and instances.
A class is a structure that represents the data and the methods to work on that
particular data. A class is defined in a separate class definition includes
methods are called the constructors that are specified to create the class
instance. A class is created at the compiling time, and then instances of the
class are instantiated either at compile time or runtime. Once the class is
defined, the number or the type of properties of that class cannot be changed.
In Java, any class can inherit the properties (methods and fields) of another
class using a keyword called extends. The following is a part of TextNote and
38
PhotoNote class that illustrates how we applied the object-oriented model in
the JavaFX app:
Superclass:
public class TextNote {
private String title;
private String url;
private String content;
private int id;
public TextNote(int id,String title, String content,String url) {
this.title = title;
this.url=url;
this.content = content;
this.id = id;
}
public void setTitle(String title) { this.title = title;}
public String getTitle() { return title; }
Subclass:
public class PhotoNote extends TextNote{
private Image photo;
public PhotoNote(int id,String title,String content, Image photo,String url )
{
//the constructor of the superclass can be invoked from the subclass
super(id,title,content,url);
this.photo=photo;
}
public void setPhoto(Image photo) { this.photo = photo;}
public Image getPhoto() { return photo; }
PhotoNote is a subclass that inherits all the properties of TextNote superclass
and additionally can add new properties. As is shown in the code, a class can
be declared public to make it accessible to all class instances, but the variables
of that class are encapsulated and are declared as private. So, it can be accessed
only through the public setter and getter methods of their class.
As opposed to the Java Programming language, JavaScript does not have a
standard way to implement OOP. It is common to find different solutions for
implementing the same thing, whether it is a complicated or something trivial
like getter/setter methods. JavaScript language is a prototype-based
programming. It does not have a class-based structure. Instead, JavaScript uses
a function to define its objects. Any object instance in JavaScript can be
39
associated as the prototype for another object, allowing the second object to
inherit the first object's properties. The code below shows our solution for
implementing the object-oriented model using JavaScript for the Electron app:
function TextNote (id, title, link , text) {
// private variables
var id= id;
var title = title;
var link = link;
var text= text;
//public methods
this.getId = function(){ return id; }
this.setId = function (newId){
id = newId; }
this.getTitle = function () {return title; }
this.setTitle = function (newTitle){
title = newTitle; }
this.getText= function (){ return text;}
…
};
function PhotoNote ( id , title ,link, text , image) {
//private variable
var image = image;
// public method
this.getImage = function (){ return image; }
this.setImage = function (newImage){ image=newImage; }
TextNote.call(this, id, title ,link, text);
}
PhotoNote.prototype= Object.create(TextNote.prototype);
PhotoNote.prototype.constructor = PhotoNote;
The code above shows that JavaScript can implement inheritance by
associating a prototypical object with a constructor function. This pattern
follows a similar model to the class model in Java, but in JavaScript, it is
allowed to add or remove properties from any object at the run time. The
40
locally scoped variables of the objects are encapsulated inside their constructor
function. Those private properties are accessed by closures functions, which
are the setter and getter functions.
2Organize projects/code
The classes and packages in Java provide a much easier way to structure the
code. So, the code in JavaFX app was divided into classes. The related classes
were grouped together in packages. The MVC design pattern which was used
in the JavaFX app did not let the application get so complicated.
On the other hand, JavaScript does not enforce particular structure in the
code. It was up to us, how we keep the code clean and organized. However,
the multi - process architecture of Electron framework had a good effect in
improving the app structure.
3- Documentation and Community Help
In JavaFX, there is a huge source of information available in Oracle that helps
us to learn and to use Java and JavaFX technologies. We got all we need about
JavaFX APIs from JavaFX Platform Standard Edition Technical
Documentation. To solve the problems that faced us during the
implementation, we used Stack Overflow in addition to many other
communities.
Learning the development in Electron framework was from the official
website of Electron. The website has good documentation that includes guides
and API reference for the latest Electron release. By demonstrating the most
important features of Electron framework, the team behind Electron created a
desktop application for demoing Electron’s modules. This demo allowed us to
discover what is possible with Electron with sample code and helpful tips for
building our Electron app. Although the Electron community is growing
quickly, but Electron is still a new technology compered to JavaFX. We can
take Stack Overflow as an example. We got 5,888 results when we searched
about Electron while we got 47,543 results about JavaFX.
4.3.2 The Database Implementation
Java interacts with a wide range of databases using Java JDBC API. SQLite
JDBC Driver was downloaded to work with SQLite DB. The JavaFX app starts
by calling the Class.forName("org.sqlite.JDBC") to register the driver in
Java. After that, Java connects to the SQLite database via JDBC using
getConnection method. The JDBC API provides Statement to submit the
SQL statements to the database and ResultSet objects to hold data retrieved
from the database after an SQL query is executed using Statement objects.
In Electron, it is possible to employ any web technology in the app. Local
storage, web SQL, and indexed database are the three available ways to store
data on the client side. The Web SQL Database API was used for the database.
41
Web SQL Database is a spec that brings SQL in the web apps to manipulate
client-side databases.
The web SQL, which is basically SQLite database, is implemented by using
the three core methods. OpenDatabase method which is called in the JQuery
document “ready” function to create the database object either using an
existing database or creating a new one. Transaction method to control a
transaction and performing either commit or roll-back based on the situation.
And executeSql method to perform CRUD operations in the Text/Photo Notes
by executing SQL queries.
4.3.3 The Richness of Graphical User Interface
JavaFX comes with a large set of built-in GUI components that save a lot of
time when building a desktop application. In general, a JavaFX application
contains at least one stage which corresponds to a window. Each stage contains
a scene. Each scene can contain an object graph of layouts, controls, etc., called
a scene graph. In our JavaFX application, the scene graph is built using Scene
Builder. The result is an FXML file which then combined with the Java project
by binding the UI to the application.
When applying the GUI design, there were many controls available for us
to list our data. TableView and TreeTableView were two possible choices
which are designed to visualize an unlimited number of rows of data that are
broken out into columns. Even ListView can be similar to those controls except
it misses the column sporting. JavaFX can also integrate Swing components
like Jtable for more features such as sorting, searching, and filtering.
ListView was chosen to list the data. Each list of Text Note and Photo Note
is presented on its own ListView. To make it visible, the ListView is added to
the left side of a SplitPane which is then attached to the Scene object. If it has
more items than it can fit into its visible area, automatically, a scrollbar will be
added so that the user that can scroll up and down over the items.
The following code shows that the listProperty and ListView are bound
together using bind method:
// ListView is created in FXML file and it is given the fx:id = PhotoListview
@FXML private ListView<PhotoNote>PhotoListview;
public void refreshPhotoNoteList(){
photolistProperty.set(FXCollections.observableArrayList
(SessionHandler.gePhotoNoteList())) ;
PhotoListview.itemsProperty().bind(photolistProperty);
PhotoListview.setCellFactory(new Callback<ListView<PhotoNote>,
ListCell<PhotoNote>>() {
@Override
public ListCell<PhotoNote> call(ListView<PhotoNote>
PhotoListview) {
42
return new PhotoListCell();
…
Using a simple ListView was not enough to get the final presentation for the
Photo/ Text Notes. ListView did not allow us to present multiple labels, button,
and image in a single raw. Therefore, a ListCell has been used to solve this
issue. Every ListCell renders a single object in a single row of the listview. The
figure below shows how the ListCell is used to achieve the GUI design for the
Photo/Text Notes. The List cell contains HBox that consists of VBox with two
labels and two ImageView. The size and color of the label text are fixed in the
SceneBuilder.
Figure 4.9: ListView design in JavaFX app.
Electron app uses HTML5 and CSS to create the graphical user interface.
The GUI was built using pure HTML5 tags like the <textarea> and <input
type= “button”>. With these tags, it was easy to apply the GUI design in the
Electron app. However, visualizing the note objects using HTML5 table was
not in the same level of ease. As opposed to JavaFX, HTML5 does not provide
a visual layout tool like scene builder. Also, HTML5 does not have data grid
component like “Jtable” in Swing or other components like “TableView”,
“ListView” and”TreeTableView” in JavaFX. Another difference is that the
data bindings in HTML5 require library like knockout.js.
The below screenshot shows the panel which includes HTML5 table that is
used to create the entire view of the Text and Photo Notes.
43
Figure 4.10: HTML5 table in Electron app.
HTML5 table is created by using the <table> tag. The rows are defined with
the <tr> tag, and data/cells are defined with the <td> tag. Each row in the
table displays a Photo Note object, allowing the user to view and delete the
note. Each cell in the table contains different elements. The “onclick” method
is used to handle a click event that occurs on the element to which the “onclick”
attribute is applied. The Bootstrap components are used to create a more
responsive design.
After performing CRUD operations, the following function is called to
refresh the table in index.html file:
JS file
…
function displayPhotoNotes (arr){
photoArr= arr;
let data = ' ';
let counter = 0;
if (photoArr.length > 0) {
photoArr.forEach((PhotoNote) =>{
data+='<tr>'
// add clickable title
data+= '<td><a href="#" onclick="EditPhotoNote(' + counter +
')"><h>'+
//method to display fixed length of string
truncateNote(PhotoNote.getTitle())+'</h></a><br><p> '+
truncateNote(PhotoNote.getText())+'</p></td>'
44
// display the image of the photo note
data+= '<td><img src = "'+PhotoNote.getPhoto()+'"
rounded" alt="Cinque Terre"
width="40" height="40"></td>'
class="img-
// add “trash” button for photo note deletion
data+= '<td><a href="#" style="margin-right:10px ;"padding-top:
10px""><small><span
class="glyphicon glyphicon-trash" onclick="DeletePhotoNote(' +
counter +
')"></span></small></a></td>'
data+= '</tr>';
counter++; });
}
// inner the presentation of “ photo-p” div
document.getElementById('photo-p').innerHTML = data; };
…
Index.html
…..
<div class="panel-body">
<table>
<tbody id="photo-p"> </tbody>
</table>
</div>
…
4.3.4
The Availability of Native APIs
The simple note application features require native access to the operating
system. JavaFX and Electron framework both have provided all the required
APIs for building those features.
JavaFX applications can utilize Java API libraries to access native system
capabilities [18]. Java has set of runtime libraries that have a standard way to
access the system resources of a host computer. When writing a Java program,
the class files of the Java API will be available on any Java virtual machine.
During running the program, the virtual machine loads the Java API class files
that are referred to by program's class files. These APIs call native methods to
access the native resources of the host. So, the Java API's class files provide
the Java program with a standard, platform-independent interface to the
underlying host [6].
In Electron, the combination of Node.js and Chromium provides a way to
access the native features of the operating system.
45
“In web pages, it is not allowed to call native GUI related APIs because
managing native GUI resources in web pages is very dangerous and it is easy
to leak resources. If you want to perform GUI operations in a web page, the
renderer process of the web page must communicate with the main process to
request the main process perform those operations” [2].
This content presents our performance that we followed according to the
Electron framework website. The task of the main process in the Electron app
is to access the native GUI of the operating system, through main process APIs.
While the renderer process which is basically a web page, accesses the
operating system through JavaScript APIs and communicates with the main
process to perform native GUI operations.
1Global keyboard shortcuts (Accelerators)
The first native feature of the app is that the user can start writing Photo/Text
Note by using shortcuts. The “Ctrl + Shift + A” shortcut was defined for
writing new Text Note while “Ctrl + Shift +B” was defined for writing new
Photo Note. When the app is opened, the user can see a simple instruction of
using these shortcuts.
In JavaFX app, Keyboard shortcuts are created by a KeyCodeCombination
using a KeyCombination that is constructed of two modifiers plus the main
key. The following code shows how to open the Text Note Pane using a
shortcut:
private void keyPressed(KeyEvent e) {
MainPane.getScene().getAccelerators().put(
new KeyCodeCombination(KeyCode.A,KeyCombination.
SHORTCUT_DOWN,KeyCombination.SHIFT_DOWN),
new Runnable() {
@Override public void run() {
MainPane.getChildren().clear();
MainPane.getChildren().add(TextPane);
}});
In Electron app, the global shortcut API was used. This API allows the app
to listen to keyboard combinations and react. Since we wanted to catch a native
GUI event (global keyboard shortcut) and do an application window event
(opening Text/Photo Note form), so we used IPC module. This module handles
message sent from the main process to the renderer process.
Main process
const ipc = electron.ipcMain // ipc api to communicate with renderer process
const globalShortcut = electron.globalShortcut // global shortcut api
…
46
// callback function is attached to application ready event
function createWindow () {
…
// register shortcuts
globalShortcut.register('ctrl+shift+A', function () {
mainWindow.webContents.send('global-shortcutA');
});
globalShortcut.register('ctrl+shift+B', function () {
mainWindow.webContents.send('global-shortcutB');
});
app.on('will-quit', () => {
// Unregister shortcuts
globalShortcut.unregister('ctrl+shift+A')
globalShortcut.unregister('ctrl+shift+B')
})
Renderer process
const ipc = require(‘electron’).ipcRenderer //ipc api to communicate with
main process
…
ipc.on('global-shortcutA', function () {
bulidTextNoteForm();
});
ipc.on('global-shortcutB', function ( ) {
buildPhotoNoteForm();
});
There are two important things presented in the code above. First, the global
shortcuts are registered after the app “ready” event. Second, sending messages
via ipc from the main process to the renderer process is made using
“mainWindow.webContents.send(...)”. So, if the registered shortcut is pressed,
the ipc main send a message to ipc renderer to open the corresponding form.
2- Drag and drop image file
The second feature is that the app allows the user to add an image to the note
by dragging and dropping an image file on the drop area.
JavaFX provides javafx.scene.input. DragEvent and javafx. scene. input.
Dragboard classes for accessing a chosen file that will be handled by two
events. The onDragOver event is triggered when the mouse is dragged over the
scene's interface. It takes the transfer mode (TransferMode.COPY) to allow
only copying of the photo, not moving, or referencing. Next, the
OnDragDropped event occurs when the user has released the mouse from the
photo:
47
@FXML
private void setOnDragOver(DragEvent event) {
Dragboard db = event.getDragboard();
if (db.hasImage() || db.hasFiles()) {
event.acceptTransferModes(TransferMode.COPY);
}
}
@FXML
private void setOnDragDropped(DragEvent event) {
Dragboard db = event.getDragboard();
if (db.hasImage()) {
MyImage.setImage(db.getImage());
…
To implement this feature in the Electron app, we used HTML5 API.
Electron allows using HTML5 file API in the renderer process to work
natively with files on the filesystem. The DOM’s File interface provides
abstraction around native files in order to let users work on native files directly
with the HTML5 file API [2].
HTML drag and drop uses the DOM event model and drag events types. To
start a drag operation, a user selects image file with a mouse and drag it to the
target place and then release the mouse. The “FileReader” object in drop
event asynchronously reads the contents of the image file that is stored on the
user's computer. The code below shows the implementation of drag and drop
feature in the Electron app.
Renderer process
const holder = document.getElementById('holder');
//Fired when an element or text selection is being dragged.
holder.ondragover = () => {
return false; }
// Fired when a drag operation is being ended
holder.ondragleave = holder.ondragend = () => {
return false; }
// Fired when an element or text selection is dropped on a valid drop
target
holder.ondrop = (e) => {
e.preventDefault()
for (let f of e.dataTransfer.files) {
var fileReader = new FileReader();
fileReader.onload = function(fileLoadedEvent) {
48
let srcData = fileLoadedEvent.target.result; // <--- data: base64
document.getElementById('img-test').src= srcData;
}
fileReader.readAsDataURL(f);
return false; } }
3Copy and paste from clipboard
The third feature in this app is using clipboard. When clicking on “copy”
button, the app copies the content of TextArea to the clipboard. When clicking
on “paste” button, the app paste the content of the clipboard in the TextArea.
Copying and pasting text in JavaFX requires the import of
javafx.scene.input.Clipboard and javafx.scene.input.ClipboardContent
class. A ClipboardContent object holds the string of text. The Clipboard object
allows to copy and paste the text passed from ClipboardContent as it is shown
in the following code:
Clipboard clipboard = Clipboard.getSystemClipboard();
@FXML
private void copy(ActionEvent event) {
ClipboardContent CbContent = new ClipboardContent();
CbContent.putString(content.getText());
clipboard.setContent(CbContent);
}
@FXML
private void paste(ActionEvent event) {
content.setText(clipboard.getString());}
In the Electron app, Clipboard API is used. This API allows to make copy
and paste operations and it also has a method for copying text as markup
(HTML) to the clipboard. The following code shows the functions for copying
and pasting from the clipboard:
Renderer process
const clipboard = require('electron').clipboard // clipboard api
….
function copy (){
let content = document.getElementById('textarea').value;
clipboard.writeText(content); // copy to clipboard
}
function paste (){
let textContent = document.getElementById('textarea').value
let pasteContent = textContent+' '+ clipboard.readText(); // paste from
cliboard
document.getElementById('textarea').value=pasteContent;}
49
4- Opening external links in the default browser
The fourth feature of our app allows the user to use the app to open an external
URL.
In JavaFX app, java.awt.Desktop class is shipped with the Java SE edition,
and it used to launch the default browser to display a URI from
java.net.URL class. This class represents a Uniform Resource Locator, a
pointer to a “resource” on the World Wide Web. The following code shows
how to open an external link:
private void OpenttextUrl(ActionEvent event) {
…
Desktop.getDesktop().browse(new URL(urlTxt.getText()).toURI());
…
}
In the Electron app, the shell API is used to implement this feature. This
API provides functions related to desktop integration like opening a URL in a
browser. The following code shows a function uses the shell API for opening
a URL:
Renderer process
const shell = require('electron').shell // shell api
…
function openURL (){
…
shell.openExternal(link); }
5- Showing native system dialog
The last native feature in the app shows a native error dialog when opening
invalid URL.
JavaFX includes simple javafx.scene.control.Alert class that allows
showing an error message, warning, and confirmation dialog. As long as the
Alert is shown the user cannot interact with the rest of the application. The
showAndWait() blocks code execution until the Alert is closed. The following
code shows how to present error dialog in the JavaFX app:
…
Alert alert = new Alert(AlertType.ERROR); // alert type is error dialog
50
alert.setTitle("Error Dialog");
alert.setHeaderText("an Error Message");
alert.setContentText("URL is not correct!" );
alert.showAndWait();
…
In the Electron app, the dialog API is used to add this feature. Electron dialog
module allows to use native system dialogs for opening files or directories,
saving a file, displaying informational messages or error messages. The dialog
module is a main process module, because this process is more efficient with
native GUI event and it allows the call to happen without interrupting the
visible elements in the renderer process. The code below shows how the
renderer process communicates with the main process to do GUI operation.
Main process
const ipc = electron.ipcMain // ipc api to communicate with renderer process
const dialog = electron.dialog // native dialog api
…
// method to show error dialog
ipc.on('open-error-dialog', function (event) {
dialog.showErrorBox('An Error Message', 'URL is not correct')
})
Renderer process
const ipc = require('electron').ipcRenderer // ipc api to communicate with main
process
…
function openURL (){
…
// call error dialog method from main process
ipc.send('open-error-dialog'); }
4.4 Performance Measuring
The performance that is supposed to be measured in this thesis has been
described as the performance of JavaFX and Electron application. That means
it is not the performance of the technologies, but rather the performance that
can be achieved by an application using the technologies that are of interest.
JavaFX and Electron application have been implemented and are ready to be
used. The two experiments that will be achieved using these applications are
the execution time and memory usage measurement. The CRUD actions for
each note type have been chosen as measurement targets.
The performance is measured manually. In Create and Update action, the
measurement starts when the Save button is pressed until the added or updated
51
note is shown on the list. While in the Read action, it starts when one of the
recorded notes is clicked until this note is presented in the view area. Regarding
the Delete action, the measurement begins when the Delete button is pressed
and ends after the note's disappearance from the list.
To measure the execution time and memory usage of JavaFX application,
NetBeans IDE was used, while in Electron, we used Chrome DevTools. Each
measurement is done five times for each action in both applications and the
average of each action measurement is taken as a result.
52
5
Result
This chapter contains the results that are found after the implementation. The
results are divided as the following:
5.1
Results of the Performance Measuring
The results of the execution time and memory usage experiments are outlined
in tables and to be analyzed.
5.1.1
Execution Time
The result of the execution time is presented in a millisecond. The tables below
show that JavaFX application has a higher execution time than Electron in
Create, Read, Update, and Delete actions. Read action is the fastest action in
both applications because it does not require to read the notes from the
database. It only reads the note from the list and presents it in the corresponding
form. The Create, Update, and Delete actions in both applications take longer
time because they require interaction with the database.
Text Note
Framework
Create
Read
Update
Delete
JavaFX
22.7
12.2
16.0
18.0
Electron
5.5
2.5
5.5
4.0
Table 5.1: Execution time for the CRUD actions of Text Note in millisecond.
Figure 5.1: Execution time for the CRUD actions of Text Note in millisecond.
53
Photo Note
Framework
JavaFX
Create
25.0
Read
15.6
Update
21.0
Delete
20.6
Electron
13.5
4.5
12.5
9.2
Table 5.2: Execution time for the CRUD actions of Photo Note in millisecond.
Figure 5.2: Execution time for the CRUD actions of Photo Note in millisecond.
5.1.2
Memory Usage
The result of the memory usage is taken in Megabyte. The tables below show
the results that are taken after executing the CRUD actions. The results refer
that JavaFX app consumes more memory than Electron. As we can see in the
following tables, the Electron CRUD values are constant and have no big
differences, but in the JavaFX application the values fluctuate.
Text Note
Framework
Create
Read
Update
Delete
JavaFX
15.38
9.58
15.36
12.59
Electron
6.49
6.40
6.49
6.47
Table 5.3: Memory usage for the CRUD actions of Text Note in megabyte.
54
Figure 5.3: Memory usage for the CRUD actions of Text Note in megabyte.
Photo Note
Framework
Create
Read
Update
Delete
JavaFX
16.28
11.38
16.13
15.38
Electron
6.53
6.47
6.52
6.50
Table 5.4: Execution times for the CRUD actions of Photo Note in megabyte.
Figure 5.4: Memory usage for the CRUD actions of Photo Note in megabyte.
55
5.2 Results of the Software Comparison
The tables below contain an overview of the findings from the implementation
of JavaFX and Electron apps:
1. The programming language
The
programming
language
JavaFX app
Electron app
1. Java- class based.
Object-oriented
Programming
2. Standard approach to
implement OOP.
3. Constructor method to
define a class.
4. Cannot add or remove
properties to objects at
run time.
5. a subclass inherits a
superclass using
“extends” keyword.
Code structure
and design
Documentation
and community
help
6. Encapsulation is
achieved by private
variables.
MVC architecture.
1. Has a good documentation
that is available in Oracle.
2. Has a good community help
and lots of forums, video,
tutorials, and experts, etc.
1. JavaScript–prototype
based.
2. Different approaches for
OOP.
3. Constructor function to
define and create objects.
4. Allowed to add or remove
properties to individual
objects at the run time.
5. Inheritance is
implemented by assigning
an object as the prototype
associated with a
constructor function.
6. Encapsulation is achieved
by closure.
Electron Multi-process
architecture.
1. Has a good documentation at
the official website of Electron.
2. Desktop app is provided for
demoing Electron APIs.
3. Has not as good community as
in JavaFX.
Table 5.5: Result of the programming language.
56
2.
The Database
Database
JavaFX
Electron
Client database
JDBC/SQLite DB
Web storage/ SQLite DB
Table 5.6: Result of database.
3.
The graphical user interface
GUI
JavaFX
Electron
Technology to build UI
JavaFX
HTML5 & CSS
Drag and Drop
components tool
Availability of controls
Scene Builder
Does not provide this feature
Provides rich controls
Data grid components
Jtable from Swing
Data binding
Provides data bindings
Provides rich controls, but no
complex components like
ListView, TableView, and
TreeTableView.
Does not have data grid
components.
Does not provide data
bindings. It requires library.
Table 5.7: Result of the GUI.
57
4.
The native application programming interface (API)
API
Accelerators
JavaFX
Electron
1. JavaFX
KeyCodeCombination
API.
1. Global Shortcut, and ipc
main process API.
2. ipc renderer process API.
Drag and drop
file object
1. JavaFX DragEvent
and Dragboard API.
1. HTML5 file API.
Clipboard
1. JavaFX Clipboard
API.
1. Clipboard renderer process
API.
Opening external
links
1. awt API.
2. Java net API.
1. Shell renderer process API.
Dialog
1. JavaFX Alert API.
Table 5.8: Result of the native APIs.
58
1. ipc main process API.
2. Dialog and ipc renderer
process API.
6
Discussion
This chapter contains a discussion of the findings and general answers to the
research questions of this thesis.
6.1 Initial Discussion
With Electron is being new technology, there was a variation in the knowledge
that we have in Electron compared to JavaFX. We expected to find some
challenges and difficulties during learning Electron. However, the literature
reviews and the official website of Electron provided us a good understanding
and a solid background on everything we needed to know to build the app.
Then we used that knowledge to implement the application. As we mentioned
earlier, the applications were developed using a waterfall approach. So, in the
development, each stage is completed before the next one begins. This strategy
has helped us to keep the project on the right path as well as fulfill our
requirements. While Electron app required us to learn its particular
characteristics in development, the work in JavaFX app is done much smoother
due to our previous experience in Java programming. Moreover, using tool for
building the graphical user interface in JavaFX app as well as the richness of
websites that cover almost everything about JavaFX helped to save our time.
We are overall happy with the produced results. On one hand, using JavaFX
in this project was a good chance to refresh the Java programming skills. On
the other hand, Electron framework allowed us to discover a new way in
developing desktop apps. We do believe that Electron being a web based
technology would bring lots of web developers to desktop apps.
6.2
Discussion of Performance Test Results
Electron app is achieved better performance in both memory usage and
execution time than JavaFX Thus, the performance of Electron can give an
additional advantage for Electron apps. In general, the JavaFX heavy
components cause the delay and need more memory. And using FXML in the
JavaFX app takes slightly longer time to load and display [22]. In addition to
that, interaction with the JDBC/SQLite DB affects the JavaFX app
performance. There were noticed differences on the results when measuring
the performance of JavaFX app without interacting with the database. This
interaction was one of the reasons that make the JavaFX app slower and
consumes more memory. However, in the Electron app, the database impact is
negligible compared to JavaFX.
However, we think, it would be possible to get more valid performance results
if we have, for example a complex algorithm or graphical animation in our
application.
59
6.3
Discussion of Software Comparison Results
Both apps satisfied the functional and nonfunctional requirements. However,
several differences were found during the development. That was natural since
each approach has its own characteristic and its way in the implementation.
The development using Java object-oriented language allows developers to
leverage all the powerful features of the language. One advantage of using
Java class based language for implementing OOP concepts is that it allows the
programmer to structure and to define classes /hierarchy using special syntax.
That increases the reusability, maintainability, and readability of the code.
However, adding or removing properties by a compiler is impossible, because
the definition of the class occurs at compile time.
To organize more complex desktop applications, JavaFX provides the MVC
design pattern. This pattern is used to separate the Model from the View. The
separation allows more flexibility to design and implement the Model
considering reusability and modularity. Using this pattern also enables the user
interface to display multiple Views of the same data at the same time. That
makes the app easier to test, maintain, and to upgrade. Further, it will be easier
to add new clients just by adding their Views and Controllers.
Java and JavaFX community supports all developers. Many experts provide
support and help on all different topics. Lots of information and tools are
available to help programmers to learn and use Java and its GUI tools.
In terms of the availability of APIs, Java provides a significant set of APIs
for various things like GUI, managing Input and Output, database, and much
more. Regarding database API, SQLite library contains a JDBC interface. It is
a good choice if there is a need to access SQLite API directly. A more modern
JDBC-only driver is the SQLite JDBC package. This is a rather nice
distribution, as the jar file contains both Java classes and native SQLite
libraries for Windows, Mac, and Linux. That makes cross-platform distribution
quite easy.
JavaFX is written as a Java API and can simply reference APIs from any
Java library and then use them in the Java application. JavaFX organizes GUI
components, event handler, property system, and data binding efficiently.
Another feature of JavaFX is that it allows to integrate the data grid component
from Swing. JavaFX also has its own definition language written in XML,
called FXML which is scriptable and easy to learn. FXML is very useful as it
decouples the application logic from the user interface. It can be generated
using JavaFX Scene Builder, which is a great tool for building UI. Scene
Builder allows the developer to design the UI without any coding, just via dragand-drop components to the work area. After adding, there is a possibility to
change their properties or composition and apply CSS without having to mess
around with the Java code. In other words, it provides a visual layout
environment required for the fast, easy, and convenient design of user
interfaces.
60
In contrast, the first difference in Electron approach is using web
technologies (JavaScript, HTML5, and CSS) for building desktop apps. The
main advantage of this approach is the reusability of both code and
programming skills. Web developers do not need to know Java or any other
object-oriented language to be desktop developers. They can use only their web
skills to build desktop applications. They can also reuse the same code they
had used in web apps to create desktop versions. Using Node.js in Electron
apps also means that developers can reuse a huge ecosystem of open source
libraries to build desktop apps. In addition to that, developers can bring all used
libraries and frameworks in web development like Angular, React, and jQuery
to build cross-platform desktop apps.
Another noticeable difference in Electron is its chromium multi-process
architecture. Although that working with Electron requires learning the main
process, the renderer process, the communications between the processes and
the app flow. But the plus side is that the architecture supports building multiwindow apps. Each web page runs on its own process, which means the crash
in one process would not affect another. Electron also provides several ways
to organize and control the communication between its processes. One way is
using IPC module for sending and receiving messages. Thus, Electron can be
a good choice for building multi-window apps.
In terms of the availability of the APIs, Electron app has full access to the
native operating system APIs. Unlike normal web pages, which run in a
sandboxed environment, Electron app can use Node.js APIs to allow lower
level operating system interactions. HTML5 APIs can also be used to access
hardware devices, web storage database, etc. Web-SQLite database was used
in the Electron app to save the data on the client side. An addition to that,
Electron has its own set of APIs which provide further native features. We have
used some of them for developing the Electron app, but there are many other
useful APIs. Another important point to mention is that Electron APIs are easy
to use, clean and do not require much code.
In fact, Electron provides good documentation. The official website of
Electron contains everything about Electron like Electron quick start guide,
Electron APIs, Electron features and many other things. Also, Electron has
good support from the community, but it cannot be compared with JavaFX.
That because Electron is still a new technology for cross-platform desktop
development.
Moving to the object-oriented programming, Electron framework uses
JavaScript programming language. With JavaScript language, it is possible to
create classes with less code compared to Java. Another good point is that
JavaScript allows an easy and quick change to the behavior at runtime. We
can add and delete the properties of an object at runtime. However, using
JavaScript for implementing OOP concepts has some concerns. JavaScript
does not have a standard way to create objects, make inherence or even
encapsulation. The implementation of an object-oriented model like the used
61
model in our app is not a problem since it is not too much complicated. The
problem may occur when implementing a significant sized model with many
classes and lots of files. Then it might be hard for developers who are involved
in the development to make their code consistent. Another concern of
JavaScript OOP is the encapsulation. Encapsulation in JavaScript cannot take
benefits of using prototype functions for accessing private properties. The only
way to access them is to create closure functions. Using closure functions for
accessing private variables requires more memory in comparison with
prototype functions. The reason of that is whenever a new object is created the
closure functions would get reassigned. Therefore, Electron might be a not
good solution if the encapsulation is required.
Finally, Electron uses pure HTML5 and CSS for creating the user interface.
It does not have drag and drop solution which can easily build the interface,
and, if the data binding is required, the developer needs to use a framework.
Almost everything is possible to build with HTML5. HTML5 has a rich control
to layout the GUI, but using them can be hard in case of implementing complex
components like tree or table that includes complex interactions.
As we mentioned before, the advantages and disadvantages of the
frameworks depended on the limited features which were used according to
the implemented applications. The resulted comparison did not lead to big
differences or missing features in one of these frameworks. Building a more
complex app with additional requirements may increase accuracy and validity
in comparison.
62
7
Conclusion
This chapter contains a conclusion of the whole thesis includes formal answers
to the research questions and some information about the possible further work.
7.1
Conclusion
This thesis provides the comparison between two types of cross-platform
development for desktop applications: object-oriented based solutions versus
web based solutions. JavaFX is based on Java programming language which
has a slogan that says “write once, run anywhere". In contrast, Electron is a
web-based technology and is currently used in many companies like Microsoft,
Facebook, Slack, and Docker. Electron combines Node.js with chromium and
uses JavaScript, HTML5, and CSS languages to build desktop apps.
Two versions of the same app were developed using JavaFX and Electron
framework in this thesis. Those apps were used to compare the technologies
based on the criteria explained in section 4.3. The purpose of the comparison
is to discover the differences between the solutions and to find their benefits
and drawbacks.
7.1.1
Answers to the Research Questions
1. How does the performance of the cross-platform desktop apps differ when
developed in Electron compared to JavaFX?
By using the collected data from the performance test of the JavaFX and
Electron apps, the answer is presented as follows:
The results showed that the performance of the JavaFX app differs than the
Electron app. Electron app gives faster execution time as well as less memory
usage for CRUD operations than JavaFX. There are other theses and articles
that popularized the same issue about JavaFX app performance. According to
a performance study made by Olle F.A. Öijerholm who measured the
performance of two web application technologies, JavaFX and Silverlight 2.
JavaFX was consistently more than ten times slower than Silverlight 2 [13].
Another performance measuring study was presented by Marc Fasel. The
performance comparison was between Node.js and Java EE application. Java
was 20% slower than Node.js [14].
2. What are the benefits and drawbacks of both technologies (Electron &
JavaFX) for cross-platform development for desktop apps?
By using the collected data from the comparison of the JavaFX and Electron
apps, the answer is as follows:
63
The development in Electron which is based on web languages (JavaScript,
HTML5, and CSS) has a set of advantages. The biggest advantage of this
approach is that it offers an opportunity for the web developers to become
desktop developers as well. Developers can use any framework, library, and
code for web apps to build desktop apps. In general, JavaScript is a powerful
language and has many advantages, but, in the terms of OOP, it has some
considerations. The implementation of OOP concepts is not straightforward
like Java language. Another issue with JavaScript is that encapsulation is only
achieved via closure functions which are not efficient as prototype functions.
For building multi-window apps, the developers can exploit the advantage
of the multi-process architecture of Electron. On the other hand, JavaFX gives
the freedom to the developers to decide which design patterns they want to use.
Applying FXML helps to build the apps in MVC design pattern.
Both frameworks can build a rich graphical user interface. However, if the
easiness is of interest, it is much easier and faster to build the graphical user
interface with JavaFX Scene Builder tool.
In terms of the availability of native APIs, both frameworks provided the
required APIs to build the native features of the apps. In general, Electron apps
can use the rich APIs of Node.js, HTML5, and Electron while JavaFX apps
can use Java and Java GUI APIs to access the operating system. Electron
especially allows an easy use to its APIs by providing a desktop app with a
sample code demonstrates the core features of Electron API. In addition to that,
all the information about Electron and its features are well documented on the
official website of Electron framework. JavaFX, in contrast, is older than
Electron which means an enormous community, great documentation, and
more availability of specialists for support.
After finding the answers for the advantages and drawbacks of both
technologies, we have an idea of the efficiency and capacity of each framework
to build the desktop application. We cannot judge which one is the best
because that is depending on the required application to be built. In other
words, before developers can develop a real application, they need to address
their requirements first. Then, they can decide which technology to approach.
7.2
Future Work
In this thesis, we covered some important aspects of cross-platform desktop
development using JavaFX and Electron framework. However, there are many
directions for future work. It is possible to test other features of both
frameworks because they have more features that we did not use due to the
time limitation in this thesis. Other features that can be investigated are:
● Native features like Notifications, trays, menus, etc.
● Multithreading.
● Security.
64
●
●
Code portability (the ability of the code to be ported to other platforms).
Packaging and distribution.
Additional to that, comparing our applications with a native application
would be an interesting thing to do and compare the performance as well. That
to see how JavaFX and Electron performance can be compared with native
development.
65
References
[1] A. Cioroianu, "Java desktop development - O’Reilly media," 2004.
[Online]. Available:
http://archive.oreilly.com/pub/a/onjava/2004/02/18/desktop.html. Accessed:
Nov. 1, 2016.
[2] "Electron," Electron. [Online]. Available: http://electron.atom.io/.
Accessed: Nov. 1, 2016.
[3] A. KS, "Frameworks & tools to develop cross-platform desktop Apps –
best of," in Desktop, HKDC, 2007. [Online]. Available:
http://www.hongkiat.com/blog/frameworks-tools-build-crossplatformdesktop-apps/. Accessed: Nov. 1, 2016.
[4] Xanthopoulos S, Xinogalos S. "A comparative analysis of cross-platform
development approaches for mobile applications", in 6th Balkan Conference
in Informatics, 2013, Thessaloniki,Greece.
[5] 2017. (2016, December 28). Cross-platform development for Desktops:
Choosing the right technology. Retrieved January 11, 2017, from
https://mobidev.biz/blog/crossplatform_development_for_desktops_choosing_the_right_technology
[6] B. Venners, "Java’s architecture and the challenges and Opportunies of
networks," 1996. [Online]. Available:
http://www.artima.com/insidejvm/ed2/introarchP.html. Accessed: Feb. 23,
2017.
[7] Copyright, "Google maps," in Wikipedia, Wikimedia Foundation, 2017.
[Online]. Available: https://en.wikipedia.org/wiki/Google_Maps. Accessed: Feb. 28,
2017.
[8] "Create cross-platform desktop Node Apps with electron," in JavaScript,
SitePoint, 2016. [Online]. Available:https://www.sitepoint.com/desktopnodeapps-with-electron/. Accessed: Nov. 3, 2016.
[9] steve kinney, Electron In Action, MEAP ed. 2016, ch. 1, pp. 2-13
[Online]. Available: https://www.manning.com/books/electron-in-action.
Accessed: Nov. 14, 2016.
[10] P. Jensen, Cross-platform Desktop Applications, MEAP ed. ch. 1, pp. 330 [Online]. Available: https://www.manning.com/books/cross-platformdesktop-applications. Accessed: Nov. 1, 2016.
66
[11] [Online]. Available:
https://en.wikipedia.org/wiki/Chromium_(web_browser). Accessed: Nov. 14,
2016.
[12] D. Kerr, "As it stands - electron security," Scott Logic, 2016. [Online].
Available: http://blog.scottlogic.com/2016/03/09/As-It-Stands-ElectronSecurity.html. Accessed: Nov. 14, 2016.
[13] O. F. A. Öijerholm, I. I. Göteborg, and T. informationsteknologi, "A
comparative study of Silverlight 2 and JavaFX performance," 2009. [Online].
Available: https://gupea.ub.gu.se/handle/2077/21662. Accessed: Mar. 1,
2017.
[14] M. Fasel, "Performance comparison between Node.js and java EE DZone performance," dzone.com, 2013. [Online]. Available:
https://dzone.com/articles/performance-comparison-between. Accessed: Mar.
1, 2017.
[15] Microsoft, "Chapter 16: Quality attributes," 2017. [Online]. Available:
https://msdn.microsoft.com/en-us/library/ee658094.aspx. Accessed: Feb. 28,
2017.
[16] "Java (software platform)," in Wikipedia, Wikimedia Foundation, 2016.
[Online]. Available: https://en.wikipedia.org/wiki/Java_(software_platform).
Accessed: Nov. 15, 2016.
[17] Pandey, J. (2016, June 27). Retrieved February 27, 2017, from What is
the advantages of desktop application over web application?,
https://www.quora.com/What-is-the-advantages-of-desktop-application-overweb-application.
[18] "JavaFX Architecture," in oracle, 2013. [Online]. Available:
http://docs.oracle.com/javafx/2/architecture/jfxpubarchitecture.htm#A1106498. Accessed: Nov. 15, 2016.
[19] "1 JavaFX overview (release 8)," 2008. [Online]. Available:
https://docs.oracle.com/javase/8/javafx/get-started-tutorial/jfx-overview.htm.
Accessed: Mar. 1, 2017.
[20] WithoutBook, "Difference between AWT and swing," 2016. [Online].
Available:
http://www.withoutbook.com/DifferenceBetweenSubjects.php?subId1=53&s
67
ubId2=54&d=Difference%20between%20AWT%20and%20Swing.
Accessed: Nov. 15, 2016.
[21] H. E. S. Engineer and C. E. AG, "JavaFX 8 - Dzone Refcardz,"
dzone.com. [Online]. Available: https://dzone.com/refcardz/javafx-8-1.
Accessed: Dec. 19, 2016.
[22] "What are the pros and cons of using FXLMs and without using
FXMLs?," in Stack Overflow, 2016. [Online]. Available:
http://stackoverflow.com/questions/20965691/what-are-the-pros-and-cons-ofusing-fxlms-and-without-using-fxmls. Accessed: Dec. 24, 2016.
[23] Manuel Palmieri, Inderjeet Singh, Antonio Cicchetti, A. Comparison of
cross-platform mobile development tools. In: 2012 16th International
Conference on Intelligence in Next Generation Networks (ICIN); 2012.
[24] Raj R, Tolety SB. A study on approaches to build cross-platform mobile
applications and criteria to select appropriate approach. In: 2012 Annual
IEEE India Conference (INDICON); 2012. p. 625–9.
[25] A. Goldenberg, "Pros and cons of developing native vs. Cross-platform
web-based mobile application," 2002. [Online]. Available:
https://www.dbbest.com/blog/pros-and-cons-of-developing-native-vs-crossplatform-web-based-mobile-application/. Accessed: Feb. 23, 2017.
[26] "JavaFX," in Wikipedia, Wikimedia Foundation, 2017. [Online].
Available: https://en.wikipedia.org/wiki/JavaFX#JavaFX_8. Accessed: Feb.
23, 2017.
68
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement