How do we test the exception?

[Kadir]

There's a function of DoIt, which is the test (JUnit). If the argument is null, the function must remove the exception. I'm checking this:

public final void TestDoIt() {
    try {
        // Вызываю функцию
        DoIt(null);
        fail("doit(null) должна выкинуть исключение");
    } catch (NullPointerException e) {
    }
}

Is that right or is there something better?

[Amritpal]

That's right for JUnit until version 4.

New versions can (and need) use annotations:

 /users/1155/test (expected = NullPointerException.class)
public final void doIt() {
    DoIt(null);
}