JMockit Capture and replace interface method logic

Question

How can you capture the calling of an interface method and replace the captured interface method's logic with the mocked one, using JMockit?

Answer 1

Yes, it is clearly described in "The JMockit Tutorial", here: http://jmockit.googlecode.com/svn/trunk/www/tutorial/StateBasedTesting.html#interfaces

Here comes the copy-pasted example of code that mocks the CallBackHandler interface and provides own implementation of the handle method:

@Test
public void mockingAnInterface() throws Exception
{
    CallbackHandler callbackHandler = new MockUp<CallbackHandler>() {
        @Mock
         void handle(Callback[] callbacks)
         {
             assertEquals(1, callbacks.length);
             assertTrue(callbacks[0] instanceof NameCallback);
         }
    }.getMockInstance();

    callbackHandler.handle(new Callback[] {new NameCallback("Enter name:")});
}