Expected index out of bound exception

Question

my teacher give me this code:
@Test(expected = IndexOutOfBoundsException.class)
  public void testShouldThrow() {
    OurList<String> list = new OurArrayList<String>();
    list.insertElementAt(1, "A");
  }I don't understand what he means by the expected = IndexOutOfBoundException.class
I mean what he is trying to say here is that I can't insert an element at index 1 if index 0 is not yet filled. But I tried this code on j unit and it compiles?? Can somebody explain this to me

Answer 1

I see..so the test passed because the indexOutOfBound
worked. Can you tell me what does the syntax means?
expected IndexOutOfBoundException.classWell I'm not so familiar with the annotation syntax and wasn't aware of JUnit having @Test(...) annotations, but I'd suggest reading up on JUnit at their website http://junit.org/index.htm
But intuitively speaking, it means when the method terminates, the JUnit framework sees the return value or exception, and compares its class with the above. Basically they have a catch block behind the scenes something like this:
catch (Throwable t)
  if (t.getClass() == expectedClass)
    testPassed();
  else
    testFailed();
}where expectedClass in this case equals IndexOutOfBoundsException.class