Mockito

Java mocking is dominated by expect-run-verify libraries like EasyMock or jMock. Mockito offers simpler and more intuitive approach: you ask questions about interactions after execution. Using mockito, you can verify what you want. Using expect-run-verify libraries you often look after irrelevant interactions.

Mockito has similar syntax to EasyMock, therefore you can refactor safely. Mockito doesn't understand the notion of 'expectation'. There is only stubbing or verifications.