Among other things it allows you to arrange your parameterized JUnit-test like this:

@RunWith(CallbackParamsRunner.class)
@WrappedRunner(SpringJUnit4ClassRunner.class) // or almost any other runner(!)
@ContextConfiguration
public class TestWithTwoRunners {…}

The above allows you to run a parameterized test with SpringJUnit4ClassRunner!

The parameterization offered by CallbackParams works in ways that are quite different from the parameterization alternatives that you have listed. The intention of CallbackParams is to make your parameterized tests easier to maintain when your software evolves. It is explained and demonstrated in the tutorials on the website:

http://callbackparams.org

The maintainability is achieved by something I refer to as “callback-parameterization”.

There is also support for a more traditional parameterization-style (with @ParameterizedValue) and if you feel naughty you can of course try to combine it with another parameterization runner:

@RunWith(CallbackParamsRunner.class)
@WrappedRunner(Parameterized.class)
public class TestDoubledParameterization {…}

Parameter-values are combined under the hood. The default is a 2-element (or pairwise) combining style – but the combinatory machinary is plugin-based, so you can bake your own “CombineStrategy”:

@RunWith(CallbackParamsRunner.class)
@CombineConfig(strategy=CombineCompletely.class, maxCount=1000)
@WrappedRunner(RunnerOfYourChoice.class)
public class TestWithManyCombinations {…}

Please try it!