The Test annotation supports two optional parameters. The first, expected, declares that a test method should throw an exception. If it doesn't throw an exception or if it throws a different exception than the one declared, the test fails. For example, the following test succeeds :

@Test(expected=IndexOutOfBoundsException.class) public void outOfBounds() {
       new ArrayList<Object>().get(1);
    }

The second optional parameter, timeout, causes a test to fail if it takes longer than a specified amount of clock time (measured in milliseconds). The following test fails :

@Test(timeout=100) public void infinity() {
       while(true);
    }