"Forked Java VM exited abnormally" error from junit tests

I faced a similar issue. I ran the junit tests as an ant task. I added the showoutput="yes" ant junit property and ran the ant junit task. It then showed the exception stack trace that caused the forked jvm to exit.

For me, it was an "java.lang.OutOfMemoryError" in the forked VM (junit task with fork="yes") which made this message appear in the main VM.

The OutOfMemory was visible in the ant log (well, is visible since it's still present).

I use ant 1.7.1, so no hope with upgrading ant.

After putting the same VM parameters in "Run>External tools>External tools>JRE" than in Eclipse.ini (-Xms40m -Xmx512m -XX:MaxPermSize=256M) the problem is solved.

I keep fork to "no" to be sure ant use the parameters.

I believe I saw this error once when I ended up with multiple versions of junit on my classpath. Might be worth checking out.

This can occur when an uncaught RuntimeException is thrown. Unfortunately, the junit ant task doesn't output the exception so there isn't an easy way to determine the root cause. You can work around this by running the test case from the command line where the exception will be shown.

java <vm-args> org.junit.runner.JUnitCore <test-class-name>

In my case, an IllegalArgumentException was being thrown.