My JUnit tests works when run in Eclipse, but sometimes randomly fails via Ant

The core of my question is that I am concerned that my Ant build file is开发者_JAVA百科 missing something that will allow a test to finish and clean itself up. The details are below.

I have a suite of tests that always passes when I run it through Eclipse, but sometimes passes or fails when I run it using my Ant build. The tests use openCL via JOCL so I have limited memory on the GPU and it has to be managed correctly. I get this in my output sometimes when I run my Ant build,

[junit]     Caused an ERROR
[junit] CL_MEM_OBJECT_ALLOCATION_FAILURE
[junit] org.jocl.CLException: CL_MEM_OBJECT_ALLOCATION_FAILURE

The problem can not be in the test itself. I think it is that my most memory hungry test is invoked at the end of the suite. When this last test is invoked, somehow the GPU is left in a bad state from my previous tests. This doesn't happen when I run the tests through Eclipse. It has never failed in my Ant build when I make the memory hungry test the first test in the suite. Is this a familiar case? Why does running the tests through Eclipse always work? Is there anything I can try?

Here is the testing target in my Ant build:

<target name="test" if="testing.enabled">
    <mkdir dir="${test.bin.dir}" />
    <javac srcdir="test" destdir="${test.bin.dir}" debug="true" classpathref="testclasspath" source="1.6"/>
    <junit haltonerror="true" haltonfailure="true">
        <classpath refid="testclasspath"/>
        <formatter type="plain" usefile="false" />
        <batchtest>
            <fileset dir="test">
                <include name="*Test.java"/>
            </fileset>
        </batchtest>
    </junit>
</target>

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If you are really sure no left-over cleanup is missed in your code, you can create a JUnit test suite and run that from both eclipse and ant. By creating a test suite you make yourself independent of the sequence of tests that eclipse (order within the project?) and ant (order within the filesystem?) use and determine the order yourself in both cases.

If you are not really really sure your code is issue-free you could make a test suite which starts of by calling Collections.shuffle() on the list of test classes to introduce unknown test execution order in both eclipse see if your tests still never fail.

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The problem could be that you do not free memory in your test cases. JUnit instanciates all test classes when it is started and then runs them, as far as I know. If you have fields that reference objects in your test classes all fields will stay assigned through the whole testrun when you don't assign null to them in a tearDown() method. For example:

class Test extends TestCase {

    private Data data;

    public void setUp() {
        data = new Data();
    }

    public void tearDown() {
        data = null; // required to allow garbage collection of the Data object
    }

}

Maybe Eclipse unreferences the Test instances after they are executed, so that the fields can be garbage collected. But using the standard JUnit TestRunner you will end up with a lot of objects that are not used anymore but that are still referenced and eat up all your memory.

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If the tests are passing in Eclipse and failing elsewhere, then you're suffering from one of the many kinds of developer syndrome: "...but It works when I run it here...!"

You have managed to configure Eclipse to let you work with your code, the functionality is in, yet your code is, this far, not deployable, which means it's not done.

Shelve Eclipse for a while (stop blaming it), and drop to the command line (or use a different IDE) until things work. Try the code on a different computer, even!

Then go back to Eclipse, and repeat the above cycle until you're certain that any dependencies on Eclipse or your hard disk/setup have been removed. In the end, your code must be able to run on who-knows-which server.

Have you tried having a clean Eclipse installation (on a different computer) take a shot at a source-only snapshot of the code? It would be a good configurations management test that I'm quite sure your code won't pass as it stands.

Seriously try to get Eclipse doing its magic on a clean (virtual) machine. It won't work on a first run, but you'll learn what you did to make it work under your setup.

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Let me google that for you:

Ant looks for an environment variable called ANT_OPTS which is use to set Java parameters. > Just set the environment variable and off you go. So I added the following to increase the > heap size:

export ANT_OPTS=-Xmx256m

When running withing Eclipse, the JVM (and therefore Ant) most likely already has more memory than default.