Java JUnit test case

For example, in a method

public void divide(Integer a){
 //.....
}

In a Java test, we need to test a parameter as String, null, 0, Long .... , do we have a tool which will automatically test these all cases开发者_StackOverflow ?

Thanks

First, the compiler will not let you pass String nor Long so there's no point in unit-testing these.

Second, while there are some tools like the one you're describing, I wouldn't recommend them. Effective unit testing is not about trying to cover as much of the state space as possible (because the state space is infinitely large). It is about the wise choice of the "significant" cases. The one who decides what is considered to be significant is you, the programmer.

Well you can write this yourself using a JUnit TestCase. I don't know of any free tools which will automatically bombard it with all possible inputs to see how it will react, but I do know of the AgitarOne software product (commercial) which does this kind of testing. It's called agitation and lets you explore how your code behaves with nulls, max values, min values, etc.

Why not use JUnit 4 with a Parameterized test case? JUnit 3 did not support parameterized test cases OOTB, but JUnit 4 has specific API to accept arguments and invoke your test case using those parameters as input. Should that be feasible in your case?