fat headless eclipse

Example of headless eclipse application packaged as single executable jar.

Assuming build passed there will be cli.jar you can run on the command line:

java -jar cli.jar arg1 2
Debug options:
    file:/home/travis/build/yoosiba/fhe/com.github.yoosiba.fhe.parent/com.github.yoosiba.fhe.check/true not found
13:48:54:190 start install bundles
13:48:54:191 INSTALL bundle com.github.yoosiba.fhe.application_1.0.0.jar
13:48:54:237 INSTALL bundle com.github.yoosiba.fhe.core_1.0.0.jar
13:48:54:266 INSTALL bundle com.github.yoosiba.fhe.extension_1.0.0.jar
13:48:54:294 INSTALL bundle org.eclipse.core.contenttype_3.6.0.v20170207-1037.jar
13:48:54:322 INSTALL bundle org.eclipse.core.jobs_3.9.0.v20170322-0013.jar
13:48:54:343 INSTALL bundle org.eclipse.core.runtime_3.13.0.v20170207-1030.jar
13:48:54:348 INSTALL bundle org.eclipse.equinox.app_1.3.400.v20150715-1528.jar
13:48:54:379 INSTALL bundle org.eclipse.equinox.common_3.9.0.v20170207-1454.jar
13:48:54:388 INSTALL bundle org.eclipse.equinox.preferences_3.7.0.v20170126-2132.jar
13:48:54:438 INSTALL bundle org.eclipse.equinox.registry_3.7.0.v20170222-1344.jar
13:48:54:479 SKIP INSTALL (already installed) bundle org.eclipse.osgi_3.12.0.v20170512-1932.jar
13:48:54:480 finish install bundles
13:48:54:480 load bundle and invoke its method
13:48:55:246 app.Activator :: start : begin
13:48:55:262 app.Application :: main : begin
13:48:55:263 app.Application :: doMain : begin
13:48:55:265 core.Greeter :: greet : start
13:48:55:268 Hi, my name is Application.main with args [arg1, 2]
13:48:55:269 core.Greeter :: greet : end
13:48:55:566 BTW, Platform.isRunning() : true
13:48:55:567 Let's exmine extensions
13:48:55:580 Collecting data
13:48:55:581 Collecting data from org.eclipse.core.internal.registry.ConfigurationElementHandle@9
13:48:55:595 ExtensionActivator :: start : begin
13:48:55:601 Extensions data: com.github.yoosiba.fhe.extension.SomeExtension
13:48:55:602 app.Application :: doMain : end
13:48:55:602 app.Application :: main : end
13:48:55:602 invocation finished
13:48:55:645 ExtensionActivator :: stop : begin
13:48:55:648 app.Activator :: stop : begin
13:48:55:872 finally

overview

This repo presents example how to build headless eclipse application. While there are few way to do this, this example focuses on the following:

• whole app packaged into single executable jar
• no native binaries, e.g. cli.dmg or cli.exe
• uses .product definition for defining app
• no duplication of the product bundles between product file and launcher pom.xml

design

We have ordinary eclipse-bundles

• core
• application that depends on core
• extension that registers itself in the application extension point Additionally we have prod bundle of type eclipse-repository which defines our headless product, i.e. it contains the .product with the following:

   <plugins>
      <plugin id="com.github.yoosiba.fhe.application"/>
      <plugin id="com.github.yoosiba.fhe.core"/>
      <plugin id="com.github.yoosiba.fhe.extension"/>
      <plugin id="org.eclipse.core.contenttype"/>
      <plugin id="org.eclipse.core.jobs"/>
      <plugin id="org.eclipse.core.runtime"/>
      <plugin id="org.eclipse.equinox.app"/>
      <plugin id="org.eclipse.equinox.common"/>
      <plugin id="org.eclipse.equinox.preferences"/>
      <plugin id="org.eclipse.equinox.registry"/>
      <plugin id="org.eclipse.osgi"/>
   </plugins>

That is our headless application, defined by the product. You can launch it using product definition.

Besides normal tycho build for prod we use maven-assembly-plugin to create jar with all the jars of the product.

Next we define project clithat depends previously defined prod.jar. In is a wrapper / launcher for our product that contains all product jars. Additionally it contains launcher code that will:

• start eclipse / equinox platform using org.eclipse.core.runtime.adaptor.EclipseStarter
• load / install / start all our product bundles
• load concrete classes from eclipse bundles and invoke them, specifically our 'main' class from app
• after execution launcher will shutdown the platform and exit. When building the cli.jar we ensure to make it is executable and self contained.

Just for tests example contains check project with test that will call the cli.jar through the command line and assert if command line call works fine.

implementation (aka. shortcuts, hacks and duct tape)

• lots of copying and packaging-repackaging jars
• requires mvn install to pass extra jars between modules
• m2e has issues with some lifecycle mapping
• stale configuration may be in user.home/.eclipse/446492912/configuration
• uses custom class loader copied from org.eclipse.jdt.ui

based on

• custom class loader trick I saw in Lorenzo Bettini/eclipse-fatjar-example
• custom jar loader taken from Eclipse JDT jar in jar loader
• tons of code search GH code search

License

EPL 1.0 just because JDT