Java – Why does heap space run out only when running JUnit tests

eclipsejavajunitout-of-memory

When running JUnit tests, I always seem to run into this error:

eclipse outOfMemoryError: heap space

I have monitored Eclipse with JConsole and heap memory peaks at about 150MB. I have set heap memory to 1GB.

I am using the following arguments when starting Eclipse:

-vm "C:\Program Files\Java\jre1.5.0_08\bin\javaw.exe" -vmargs -Xmx1024M
-XX:MaxPermSize=128M -Dcom.sun.management.jmxremote.port=8999
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false

Does anyone know what may be causing this issue? It happens only when running JUnit tests.

Best Answer

Junit tests are run in a different vm as the Eclipse IDE. So it is that vm that is out of memory and not the Eclipse one.
You can change the settings of the test vm in the run configurations of the test.
You go to the run configurations and then under arguments, you can set the vm arguments.

Related Solutions

Java – OutOfMemory in Eclipse in a Launched process

Have you changed your launched VM arguments from the preferences window? Try this:

Window->Preferences
Java->Installed JREs
(select your jre here)->Edit..
Default VM Arguments: -Xmx1024m (or whatever size you like)

Edit 1: Based on your comments, I see that you've already tried this. I assumed that you did not try it based on the portion of your question that reads "How do I find where and how to give more memory to the process launched by eclipse launcher ?". I guess we all know what happens when we assume!

Have you considered upping the memory to something larger just to see if you can get it to run (and possibly get some more info about what is causing it to crash)? Try -Xmx2048m or larger depending on your available memory.

Can you add some information to your question that gives us an idea of what the plugin does? Is this project a web service? etc..

Java – Maven does not find JUnit tests to run

By default Maven uses the following naming conventions when looking for tests to run:

Test*
*Test
*Tests (has been added in Maven Surefire Plugin 2.20)
*TestCase

If your test class doesn't follow these conventions you should rename it or configure Maven Surefire Plugin to use another pattern for test classes.

Best Answer

Related Solutions

Java – OutOfMemory in Eclipse in a Launched process

Java – Maven does not find JUnit tests to run

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