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Java desktop application

How to Build a Desktop Application with Java

We will build a simple desktop application that will translate English text to Morse Code and vice-versa in very simple steps plus an overview of Java GUI

This is going to be an introductory lesson into the world of Graphics User Interface (GUI) with Java Programming language. ( confession: am in love with Java)

Translation Logic

First before diving into the graphics part, let’s look at the driving logic.

HashMap ( a sub-class of Map which is Key-Value store) is used to build our dictionary of English letters and their corresponding Morse code. So we have something like this:

Then, two methods were created: one to translate the English text to Morse code and the other to do the opposite. In both cases, the text is splitted using a regex that matches white space and new line characters. Each of the resulting array is processed using Java Streams for efficiency

GUI Elements In Java

Java has a rich set of GUI elements that serve as building blocks for a complete GUI Desktop Application.

JFrame

The top-most layer of Java GUI is the JFrame. It’s the outermost container that house other elements or containers. It is the part of the app with the close, minimize and maximize buttons. The following lines of code will create a JFrame object ( S >Object Oriented Programming is sweet with Java).

What the code above does is to essentially create an instance of the JFrame object, set parameters like title, layout, size, location and as well set the behaviour of the JFrame like ability to resize the frame and it’s visibility.

JPanel

This is a container, meaning it holds other elements together. The child elements are arranged in a specific order using layout managers as we will later find out. The following lines of code is responsible for creating the button row at the bottom of the Morse Text area, to the right of the application.

Other Elements Used in the App

Other Elements used in the program are

  • JButton: Clickable buttons for performing special actions. For example the clear text button beneath the English text are is created thus:
  • JLabel: Well from the name we can infer that it is a label and labels are used for well labelling things. Here is the code that created the ‘English Text’ at the top of the English text area
  • JTextArea: This element is the container where we type texts into. JTextArea is meant for multi-line texts. (Note: These elements are Java Objects and thus their behaviour and properties can be specified. Like alignment, text, location etc. You can even bind events to them as we will see later)
  • LayoutManagers: Layout managers specify how elements in a container will be arranged. In this application, we used FlowLayout and BorderLayout to specify how elements are la >Events bring GUI elements to live; so when a button is clicked, an event is generated in the system, and event listeners registered for the particular event will be invoked. The following code is responsible for registering the buttons for an ActionEvent that is fired when a button is clicked. ( lamda expression at work #java8)

    And this is where we registered the Text Areas to listen for Keyboard Events and automatically execute translation when the space bar or backspace key is pressed.

    Main Method

    In the main method, which is the entry point for all Java applications, the look and feel of the app was set to NimbusLookAndFeel which look more pretty than the default java look and feel. Afterwards, the app is fired on.

    Source Code

    The complete source code is available on this github repo. You can find instructions to contribute and run the app in the repo’s README ( remember to give it a star)

    Show some love by recommending this post so others can find it. Also tweet about it to your followers ( be a generous fellow)

    Remember to leave your responses, comments and questions below.

    Desktop Java Tutorials

    In this detailed Resource page, we feature an abundance of Desktop Java Tutorials!

    Desktop Java technologies can be used to create rich client applications and applets that are fast, secure, and portable. This page introduces all of these technologies.

    Most of the technologies are included as part of Java SE (also known as the JRE, or Java Runtime Environment), which is pre-installed on over 90% of all desktop systems on a wide range of operating systems. Other Desktop Java technologies are available as either separate downloadable Java extensions, or as open source projects on java.net. Finally, the Netbeans IDE with its integrated GUI builder brings everything together, allowing you to easily build your desktop application.

    Technology Overview

    Swing

    The Swing API provides a comprehensive set of GUI (Graphical User Interface) components and services which enables the development of commercial-quality desktop and Internet/Intranet applications. Swing is built on top of many of the other Desktop Java technologies found on this page, including JavaBeans, AWT, Java2D, Accessibility, and Internationalization.

    Here are some examples:

    Java Bindings for OpenGL (JOGL)

    JOGL is a Java programming language binding for the OpenGL 3D graphics API. It supports integration with the Java platform’s AWT and Swing widget sets while providing a minimal and easy-to-use API that handles many of the issues associated with building multithreaded OpenGL applications. JOGL provides access to the latest OpenGL routines (OpenGL 2.0 with vendor extensions) as well as platform-independent access to hardware-accelerated offscreen rendering (“pbuffers”). JOGL also provides some of the most popular features introduced by other Java bindings for OpenGL like GL4Java, LWJGL and Magician, including a composable pipeline model which can provide faster debugging for Java-based OpenGL applications than the analogous C program.

    Here are some examples:

    AWT (Abstract Window Toolkit)

    The Abstract Window Toolkit (AWT) supports Graphical User Interface (GUI) programming. AWT features the core foundation of the Java SE desktop libraries. It includes a robust event-handling model; graphics and imaging tools including shape, color, and font classes; layout managers for flexible window layouts; data transfer classes (including drag and drop) that allow cut and paste through the native platform clipboard. AWT also includes a basic set of user interface components, such as windows, buttons, etc. Swing is built on top of AWT, and in most cases the Swing high-level components are recommended instead of those in AWT. However, there are many APIs in AWT that are important to understand when programming in Swing.

    Here are some examples:

    JavaBeans

    JavaBeans technology is the component architecture for the Java 2 Platform, Standard Edition (J2SE). JavaBeans components (beans) are reusable software programs that you can develop and assemble easily to create sophisticated applications.

    Here are some examples:

    Accessibility

    Since 1973 when Section 508 of the Federal Rehabilitation Act was established, US Federal agencies have been required to purchase electronic and information technology products and services that meet the standards of Section 508. For the Java technology developer, accessibility means building the services and support into an application that enable people with disabilities to use the software. Java accessibility technologies are implemented in the Java Foundation Classes (JFC) and they comprise two separate packages: Java Accessibility API and the Java Accessibility Utilities.

    Here are some examples:

    JavaFX

    JavaFX is a software platform for creating and delivering desktop applications, as well as rich Internet applications (RIAs) that can run across a wide variety of devices. JavaFX is intended to replace Swing as the standard GUI library for Java SE, but both will be included for the foreseeable future. JavaFX has support for desktop computers and web browsers on Microsoft Windows, Linux, and macOS. JavaFX is no longer bundled with the latest Java, nor will be supported by Oracle, while it still is supported for the current long-term version Java SE 8 through March 2022.

    Here are some examples:

    Xuggler

    Xuggler is the easy way to uncompress, modify, and re-compress any media file (or stream) from Java.

    Xuggler consists of a set of Java and Native libraries, and comes with two different APIs:

    • MediaTools API A simple API for encoding and decoding audio and video.
    • Xuggler API An advanced-use API (accessible from MediaTools) for encoding and decoding audio and video.

    Here are some examples:

    Eclipse

    Eclipse is an integrated development environment (IDE) used in computer programming, and is the most widely used Java IDE. It contains a base workspace and an extensible plug-in system for customizing the environment.

    Here are some examples:

    Intellij

    IntelliJ IDEA is a Java integrated development environment (IDE) for developing computer software. It is developed by JetBrains (formerly known as IntelliJ), and is available as an Apache 2 Licensed community edition, and in a proprietary commercial edition. Both can be used for commercial development.

    Here are some examples:

    Netbeans

    NetBeans is an integrated development environment (IDE) for Java. NetBeans allows applications to be developed from a set of modular software components called modules. NetBeans runs on Windows, macOS, Linux and Solaris. In addition to Java development, it has extensions for other languages like PHP, C, C++, HTML5,[4] and JavaScript. Applications based on NetBeans, including the NetBeans IDE, can be extended by third party developers.

    Here are some examples:

    JDesktop Integration Components

    The JDesktop Integration Components (JDIC) project aims to make Java technology-based applications (“Java applications”) first-class citizens of current desktop platforms without sacrificing platform independence. Its mission is to enable seamless desktop/Java integration.

    Java 2D

    The Java 2D API is a set of classes for advanced 2D graphics and imaging, encompassing line art, text, and images in a single comprehensive model. The API provides extensive support for image compositing and alpha channel images, a set of classes to provide accurate color space definition and conversion, and a rich set of display-oriented imaging operators.

    Java 3D

    Java 3D API provides a set of object-oriented interfaces that support a simple, high-level programming model you can use to build, render, and control the behavior of 3D objects and visual environments. With the Java 3D API, you can incorporate high-quality, scalable, platform-independent 3D graphics into applications and applets based on Java technology.

    Java Sound

    The Java Sound API specification provides low-level support for audio operations such as audio playback and capture (recording), mixing, MIDI sequencing, and MIDI synthesis in an extensible, flexible framework. Java Sound is Included in Java 2 Platform, Standard Edition (J2SE), version 1.3.x and higher.

    Internationalization

    Internationalization is the process of designing software so that it can be adapted (localized) to various languages and regions easily, cost-effectively, and in particular without engineering changes to the software. Localization is performed by simply adding locale-specific components, such as translated text, data describing locale-specific behavior, fonts, and input methods. In the Java 2 Platform, internationalization support is fully integrated into the classes and packages that provide language- or culture-dependent functionality.

    Java Web Start / JNLP

    Java Web Start software provides a flexible and robust deployment solution for Java technology-based applications based on the Java Community Process program (JCP). The technology is being developed through the JCP program as JSR-56: The Java Network Launching Protocol & API (JNLP), which provides a browser-independent architecture for deploying Java 2 technology-based applications to the client desktop.

    Java Plug-In

    Java Plug-in technology, included as part of the Java 2 Runtime Environment, Standard Edition (JRE), establishes a connection between popular browsers and the Java platform. This connection enables applets on Web sites to be run within a browser on the desktop.

    Java Advanced Imaging (JAI)

    The Java Advanced Imaging API provides a set of object-oriented interfaces that support a simple, high-level programming model which lets you manipulate images easily.

    JavaHelp System

    JavaHelp software is a full-featured, platform-independent, extensible help system that enables you to incorporate online help in applets, components, applications, operating systems, and devices. Authors can also use the JavaHelp software to deliver online documentation for the Web and corporate intranet. Written entirely in the Java programming language, the JavaHelp system can run on any platform and browser that supports the Java Runtime Environment (JRE), making it ideal for use in a heterogeneous environment such as the Web and corporate intranet.

    JavaX

    The javax prefix is used by the Java programming language for a package of standard Java extensions. These include extensions such as javax.print, javax.imageio, javax.sound.sampled etc.

    Print

    Provides the principal classes and interfaces for the JavaTM Print Service API. The Java Print Service API enables client and server applications to:

    • Discover and select print services based on their capabilities
    • Specify the format of print data
    • Submit print jobs to services that support the document type to be printed.

    Here are some examples:

    Imageio

    Many common image I/O operations may be performed using the static methods of the ImageIO class.

    This package contains the basic classes and interfaces for describing the contents of image files, including metadata and thumbnails (IIOImage); for controlling the image reading process (ImageReader, ImageReadParam, and ImageTypeSpecifier) and image writing process (ImageWriter and ImageWriteParam); for performing transcoding between formats (ImageTranscoder), and for reporting errors (IIOException).

    Here are some examples:

    Sound

    Provides interfaces and classes for capture, processing, and playback of sampled audio data.

    От идеи до профита

    Как разрабатывать HTML 5 Desktop приложения на Java?

    Мотивация

    Кому могут понадобиться Desktop приложения, использующие веб-страницы в качестве UI? Отвечу прямо — всем! Всем кто страдает, пользуясь неудобными и некрасивыми приложениями.

    Для меня, как для разработчика, очень важно делать пользовательские интерфейсы удобными, интересными и позволяющими пользователям не отвлекаться от работы. Кроме того, очень хочется, чтобы интерфейсы были привлекательными и их было приятно показывать. Все эти соображения приводят нас к неутешительному выводу: существующие UI фреймворки для настольных приложений ужасны.

    Так что же такое есть в веб-приложениях, чего нет в настольных?

    • Разнообразие визуального оформления
    • Адаптивные и идеально-масштабируемые интерфейсы
    • Развитые анимации
    • Богатый набор компонентов и библиотек для разработки UI

    Похожими возможностями обладают WPF для .NET приложений и JavaFX из мира Java. Но их компоненты не могут угнаться за стремительно развивающимися web-технологиями.

    Системный кризис UI фреймворков в Java

    Если мы поближе посмотрим на JavaFX, то увидим что многие идеи Web проникли в этот фреймворк. Самая главная технология UI в web-приложениях — CSS, позволяющая великолепно выглядеть вашим приложениям. JavaFX поддерживает её для стилизации компонентов, пополняя набор стандартных CSS атрибутов своими специфичными атрибутами. При этом поддержка стандартных атрибутов CSS в компонентах JavaFX похожа на лоскутное одеяло с большими дырками и заплатками.

    Поищите в Java мире что-нибудь похожее по возможностям на JavaFX и вы сильно расстроитесь. Ничего нет! Есть жуткий Swing, есть сторонние технологии, позволяющие использовать Qt для Java, но все эти технологии являются полумерами. Так что если вы хотите написать Desktop приложение на Java, то вам придётся использовать JavaFX.

    Когда вы воспользуетесь JavaFX, вы заметите, как мало сторонних компонентов написано, и как мало людей по-настоящему полагаются на JavaFX. Это всего лишь одна из технологий.

    Спросите любого Java разработчика, какой интерфейс лучше всего сделать для Java-приложения? Вы получите один ответ, лучший интерфейс для Java-приложения — это веб-интерфейс.

    Но есть некоторые области, в которых до сих пор нельзя обойтись без Desktop приложений:

    • Приложения CALL-центров для приёма заказов такси
    • Приложения, требующие поддержку работы Offline

    А ведь как здорово было бы использовать HTML/CSS/JS для реализации UI в этих приложениях?

    Как должно выглядеть HTML5 приложение?

    Представьте, что вы запустили ваш любимый web-сайт вне браузера в виде Desktop приложения и оно выглядит, как если бы это была отдельная вкладка браузера без лишних меню, декораций и панелей, так как если бы это было приложение, которому доступны нотификации на рабочем столе и интеграция с другими приложениями, автоматическое обновление и оно может работать в отсутствии интернета.

    О, это было бы волшебно!

    Как реализовать такое приложение на Java?

    Последнее время довольно популярным стал подход, продвигаемый фреймворками Electron и node-webkit. Основная идея — скомпилировать вместе Node.JS и браузер Chromium, предоставив среду для разработки Desktop приложений на JavaScript. В такой схеме Electron предоставляет JavaScript API для возможностей, специфичных для Desktop приложений, таких как уведомления, нативные меню и многое другое, а само приложение разрабатывается на JavaScript.

    Desktop приложения на базе Electron включают две составляющие:

    1. Backend в виде Node.JS приложения
    2. Frontend в виде JavaScript компонентов или Single-Page-Application

    Но наше горе, как Java разработчиков, состоит в том, что наши приложения написаны на Java и мы не хотим их переписывать на JavaScript.

    Я изучил этот вопрос и выделил пару живых вариантов реализации HTML5 UI в Desktop приложении на Java:

    1. JavaFX WebView + Jetty
    2. Java CEF + Jetty

    Поскольку само Desktop приложение будет так же написано на Java, то мы сможем использовать все фишки Desktop приложений: создавать дополнительные окна, показывать нативные меню, добавлять иконки в трей и показывать уведомления.

    JavaFX WebView

    WebView — специальный компонент JavaFX, позволяющий отображать web-контент в приложении. WebView использует специальный движок на базе webkit, интегрированный в Java Runtime.

    Desktop Java Tutorials

    In this detailed Resource page, we feature an abundance of Desktop Java Tutorials!

    Desktop Java technologies can be used to create rich client applications and applets that are fast, secure, and portable. This page introduces all of these technologies.

    Most of the technologies are included as part of Java SE (also known as the JRE, or Java Runtime Environment), which is pre-installed on over 90% of all desktop systems on a wide range of operating systems. Other Desktop Java technologies are available as either separate downloadable Java extensions, or as open source projects on java.net. Finally, the Netbeans IDE with its integrated GUI builder brings everything together, allowing you to easily build your desktop application.

    Technology Overview

    Swing

    The Swing API provides a comprehensive set of GUI (Graphical User Interface) components and services which enables the development of commercial-quality desktop and Internet/Intranet applications. Swing is built on top of many of the other Desktop Java technologies found on this page, including JavaBeans, AWT, Java2D, Accessibility, and Internationalization.

    Here are some examples:

    Java Bindings for OpenGL (JOGL)

    JOGL is a Java programming language binding for the OpenGL 3D graphics API. It supports integration with the Java platform’s AWT and Swing widget sets while providing a minimal and easy-to-use API that handles many of the issues associated with building multithreaded OpenGL applications. JOGL provides access to the latest OpenGL routines (OpenGL 2.0 with vendor extensions) as well as platform-independent access to hardware-accelerated offscreen rendering (“pbuffers”). JOGL also provides some of the most popular features introduced by other Java bindings for OpenGL like GL4Java, LWJGL and Magician, including a composable pipeline model which can provide faster debugging for Java-based OpenGL applications than the analogous C program.

    Here are some examples:

    AWT (Abstract Window Toolkit)

    The Abstract Window Toolkit (AWT) supports Graphical User Interface (GUI) programming. AWT features the core foundation of the Java SE desktop libraries. It includes a robust event-handling model; graphics and imaging tools including shape, color, and font classes; layout managers for flexible window layouts; data transfer classes (including drag and drop) that allow cut and paste through the native platform clipboard. AWT also includes a basic set of user interface components, such as windows, buttons, etc. Swing is built on top of AWT, and in most cases the Swing high-level components are recommended instead of those in AWT. However, there are many APIs in AWT that are important to understand when programming in Swing.

    Here are some examples:

    JavaBeans

    JavaBeans technology is the component architecture for the Java 2 Platform, Standard Edition (J2SE). JavaBeans components (beans) are reusable software programs that you can develop and assemble easily to create sophisticated applications.

    Here are some examples:

    Accessibility

    Since 1973 when Section 508 of the Federal Rehabilitation Act was established, US Federal agencies have been required to purchase electronic and information technology products and services that meet the standards of Section 508. For the Java technology developer, accessibility means building the services and support into an application that enable people with disabilities to use the software. Java accessibility technologies are implemented in the Java Foundation Classes (JFC) and they comprise two separate packages: Java Accessibility API and the Java Accessibility Utilities.

    Here are some examples:

    JavaFX

    JavaFX is a software platform for creating and delivering desktop applications, as well as rich Internet applications (RIAs) that can run across a wide variety of devices. JavaFX is intended to replace Swing as the standard GUI library for Java SE, but both will be included for the foreseeable future. JavaFX has support for desktop computers and web browsers on Microsoft Windows, Linux, and macOS. JavaFX is no longer bundled with the latest Java, nor will be supported by Oracle, while it still is supported for the current long-term version Java SE 8 through March 2022.

    Here are some examples:

    Xuggler

    Xuggler is the easy way to uncompress, modify, and re-compress any media file (or stream) from Java.

    Xuggler consists of a set of Java and Native libraries, and comes with two different APIs:

    • MediaTools API A simple API for encoding and decoding audio and video.
    • Xuggler API An advanced-use API (accessible from MediaTools) for encoding and decoding audio and video.

    Here are some examples:

    Eclipse

    Eclipse is an integrated development environment (IDE) used in computer programming, and is the most widely used Java IDE. It contains a base workspace and an extensible plug-in system for customizing the environment.

    Here are some examples:

    Intellij

    IntelliJ IDEA is a Java integrated development environment (IDE) for developing computer software. It is developed by JetBrains (formerly known as IntelliJ), and is available as an Apache 2 Licensed community edition, and in a proprietary commercial edition. Both can be used for commercial development.

    Here are some examples:

    Netbeans

    NetBeans is an integrated development environment (IDE) for Java. NetBeans allows applications to be developed from a set of modular software components called modules. NetBeans runs on Windows, macOS, Linux and Solaris. In addition to Java development, it has extensions for other languages like PHP, C, C++, HTML5,[4] and JavaScript. Applications based on NetBeans, including the NetBeans IDE, can be extended by third party developers.

    Here are some examples:

    JDesktop Integration Components

    The JDesktop Integration Components (JDIC) project aims to make Java technology-based applications (“Java applications”) first-class citizens of current desktop platforms without sacrificing platform independence. Its mission is to enable seamless desktop/Java integration.

    Java 2D

    The Java 2D API is a set of classes for advanced 2D graphics and imaging, encompassing line art, text, and images in a single comprehensive model. The API provides extensive support for image compositing and alpha channel images, a set of classes to provide accurate color space definition and conversion, and a rich set of display-oriented imaging operators.

    Java 3D

    Java 3D API provides a set of object-oriented interfaces that support a simple, high-level programming model you can use to build, render, and control the behavior of 3D objects and visual environments. With the Java 3D API, you can incorporate high-quality, scalable, platform-independent 3D graphics into applications and applets based on Java technology.

    Java Sound

    The Java Sound API specification provides low-level support for audio operations such as audio playback and capture (recording), mixing, MIDI sequencing, and MIDI synthesis in an extensible, flexible framework. Java Sound is Included in Java 2 Platform, Standard Edition (J2SE), version 1.3.x and higher.

    Internationalization

    Internationalization is the process of designing software so that it can be adapted (localized) to various languages and regions easily, cost-effectively, and in particular without engineering changes to the software. Localization is performed by simply adding locale-specific components, such as translated text, data describing locale-specific behavior, fonts, and input methods. In the Java 2 Platform, internationalization support is fully integrated into the classes and packages that provide language- or culture-dependent functionality.

    Java Web Start / JNLP

    Java Web Start software provides a flexible and robust deployment solution for Java technology-based applications based on the Java Community Process program (JCP). The technology is being developed through the JCP program as JSR-56: The Java Network Launching Protocol & API (JNLP), which provides a browser-independent architecture for deploying Java 2 technology-based applications to the client desktop.

    Java Plug-In

    Java Plug-in technology, included as part of the Java 2 Runtime Environment, Standard Edition (JRE), establishes a connection between popular browsers and the Java platform. This connection enables applets on Web sites to be run within a browser on the desktop.

    Java Advanced Imaging (JAI)

    The Java Advanced Imaging API provides a set of object-oriented interfaces that support a simple, high-level programming model which lets you manipulate images easily.

    JavaHelp System

    JavaHelp software is a full-featured, platform-independent, extensible help system that enables you to incorporate online help in applets, components, applications, operating systems, and devices. Authors can also use the JavaHelp software to deliver online documentation for the Web and corporate intranet. Written entirely in the Java programming language, the JavaHelp system can run on any platform and browser that supports the Java Runtime Environment (JRE), making it ideal for use in a heterogeneous environment such as the Web and corporate intranet.

    JavaX

    The javax prefix is used by the Java programming language for a package of standard Java extensions. These include extensions such as javax.print, javax.imageio, javax.sound.sampled etc.

    Print

    Provides the principal classes and interfaces for the JavaTM Print Service API. The Java Print Service API enables client and server applications to:

    • Discover and select print services based on their capabilities
    • Specify the format of print data
    • Submit print jobs to services that support the document type to be printed.

    Here are some examples:

    Imageio

    Many common image I/O operations may be performed using the static methods of the ImageIO class.

    This package contains the basic classes and interfaces for describing the contents of image files, including metadata and thumbnails (IIOImage); for controlling the image reading process (ImageReader, ImageReadParam, and ImageTypeSpecifier) and image writing process (ImageWriter and ImageWriteParam); for performing transcoding between formats (ImageTranscoder), and for reporting errors (IIOException).

    Here are some examples:

    Sound

    Provides interfaces and classes for capture, processing, and playback of sampled audio data.

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