How to run test cases on a list of slightly different jars ?

I have a list of jar files, all containing slightly different versions of the same system.

I want to execute a set of test cases on each jar file while being able to obtain the results for each jar (via RunListener or something like that).

I am a bit confused with the class loading problems that are implied.

How can I nicely do this ?

From stackoverflow

• If the jars maintain the same interface, then all you have to do is run each test with a slighly different classpath - each time with jars from another version.

  If you're using Eclipse JUnit integration, just create N run configurations, in each one in the classpath tab specify required jars.

  If you want to do it programmatically, then I suggest you start with empty classpath and use URLClassLoader, giving it a different set of jars each time.

  Something like this:

  URLClassloader ucl = new URLClassLoader( list of jars from version1 );
  TestCase tc = ucl.loadClass("Your Test Case").newInstance();
  tc.runTest();
  
  ucl = new URLClassLoader( list of jars from version2 );
  TestCase tc = ucl.loadClass("Your Test Case").newInstance();
  tc.runTest();
  

• If you are using ant, the JUnit task takes a classpath.

  <target name="test">
    <junit ...">
      <classpath>
        <pathelement path="${test.jar.path}" />
      </classpath>
      ...
    </junit>
  </target>
  

  You can use the antcall task to call your test target repeatedly with a differed value for the test.jar.path property.