Overview
Examples
This plugin creates single-click/run launch 'apps', executables or scripts that bundle all a program's code, libraries and resources into an easily-distributable single directory.
In order to run a Java application, the JVM must be loaded with the correct configuration, namely, the main class, the classpath libraries, any system properties and VM arguments.
The platforms supported by this plugin (Mac OS X, Windows and Linux) offer different mechanisms for achieving this. This plugin integrates these mechanisms, to allow launchers to be generated for all three platforms given some common configuration and some platform-specific configuration.
The plugin also supports the use of JNI code built using the Maven NAR Plugin.
The plugin can create .app structures, and script launchers (like Linux).
For .app structures: A directory structure is created, given the name <Application>.app, with 'application stub', code, libraries, configuration and icon in the correct place. Apple provide a tool to assist with this, but it's not easily invokable from Maven. There are other plugins that can achieve the same ends. See OSX App Bundle for one such plugin.
For script launchers, a directory structure is created with 'bin' and 'lib' directories, containing the launcher script, and dependent libraries, respectively.
On Mac OS X, a popular addition to Java projects is the Quaqua look and feel library. See the Quaqua home page for details. Using this requires the addition of native libraries. The Maven dependency plugin can be used to extract these libraries from your local Maven repository into the correct location in your .app launcher structure.
See Mac OSX Examples to see how to achieve this.
The older Apple Java 1.6 system provided an 'application stub' which must be present in your .app structure. This is invoked when you launch your program from its icon. This only worked in 1.6, and for later versions of Oracle Java, an alternative 'universal' application stub (developed by Tobias Fischer) is provided. This plugin contains both the Apple stub, and the Universal one, switchable via plugin configuration.
The JVM must be loaded by some process. It is possible to do this from a .cmd file, but running the .cmd file leaves an unsightly command prompt window on screen. The Janel open source launcher can alleviate this. The original Janel home page has been discontinued by its author, Timothy Kil, but it has been continued and enhanced by Michael Knigge. See Janel Github project for details of Janel. This plugin contains the Janel console and windows .EXE files, and will copy the relevant one into your launcher structure. For the enhanced Janel, a 32- and 64-bit version is provided.
This plugin can generate launcher structures for each platform under the project's build (target) directory.
The Maven assembly plugin can then be used to package the resulting launchers into archives suitable for shipment. Assembly descriptors are provided in this plugin for simple archive creation:
It's likely that you will need to perform further processing on your launcher archives: On Windows, the launcher is typically built into an installer; On Mac OS X, the launcher is typically shipped on a disk image (.dmg); On Linux, the launcher is typically packaged into a .deb or .rpm archive. This plugin does not perform any of these functions (yet).
For more information about the goals that are available in the plugin, see the goals page.
The project's home page is at: DevZendo.org Cross Platform Launcher Plugin.