Hi all,

As tracked by https://issues.jboss.org/browse/JBIDE-10537 , we are aiming to support Jacoco for code coverage. Jacoco [1] is a very nice and easy to set up coverage tool that has no significant impact (in our use-case) on performance [2] , and that only requires a system property[3] or a maven plugin to set it up in your build [4]. It requires no instrumentation, so it does not requires additional step in build workflow to get results.
Jacoco's only current drawback is it's missing integration with Jenkins [5], but as soon as this is available, we will fully drop support for all the emma stuff to move to Jacoco.

Waiting for this Jacoco-Jenkins integration, I set up the Maven plugin in parent and Hudson jobs so that test execution produce a jacoco.exec file. This file is archived in your build result along with the output update-site.
See [6] for examples. It is set up for all components jobs on Trunk. If you don't see this on your job that means that you did not run a build since this was changed, just start a build to see the jacoco.exec file in the end.
If you want to have local report, then run "mvn clean install" (or anything that works and runs tests) in your local component module. Ensure you are up-to-date with build/ and your-component/ first.

This jacoco.exec file is pretty easy for you to consume. You can import it in Eclipse using EclEmma plugin [7] (see [8] for how-to) and you'll get reports in a dedicated view and also directly on your source code editor. Beware that your jacoco.exec files has coverage support for the latest test execution, so file that change it may be inaccurate when dealing with files that have changed in your workspace since jacoco.exec was generated.

Please add feedback to JBIDE-10537

[1] http://www.eclemma.org/jacoco/
[2] http://www.sonarsource.org/pick-your-code-coverage-tool-in-sonar-2-2/
[3] http://www.eclemma.org/jacoco/trunk/doc/agent.html
[4] http://www.eclemma.org/jacoco/trunk/doc/maven.html
[5] https://issues.jenkins-ci.org/browse/JENKINS-10835
[6] http://hudson.qa.jboss.com/hudson/view/DevStudio/view/DevStudio_Trunk/job/jbosstools-3.3_trunk.component--examples/
[7] http://www.eclemma.org/installation.html#updatesite
[8] http://www.eclemma.org/userdoc/importexport.html
--
Mickael Istria
Eclipse developer at JBoss, by Red Hat
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