我如何模拟Object.getClass？

Question

I'm working on a Java project want to write a unit test for an .equals method I have in a DTO. In the .equals method, there is a .getClass() method called by both objects under test. I want to mock this, but I can't tell what type of object it wants. I tried,

when(mockRoomInv.getClass()).thenReturn(RoomInv.class);

but sure as heck didn't do anything. What is the return type of getClass, and how do I manipulate it?

Answer 1

As Object.getClass() is final, you cannot mock that method with Mockito. I would strongly advice you to refactor your code to inject the class in another way. If that's not possible, you could try out powermock , where you could mock any final method. Object.getClass() is a bit special, so be sure to set MockGateway.MOCK_GET_CLASS_METHOD = true in powermock.

Answer 2

Object.getClass() is a final method, so you cannot mock it with Mockito.

You can mock static and final methods (as this one) and even private methods with Powermock (it's a quite cool tool ;) available at https://github.com/powermock/powermock .

You can use it with Mockito as explained in the Mockito wiki article . There you will find some useful examples.