A few weeks ago I have switched my favourite mock testing framework from Easymock to jMock. Not that I would say that Easymock is bad or has problems (I haven’t encountered any), I just found jMock more intuitive and it seems that it heavily relies on equals() to check test behaviour. After I started using jMock I had put my eyes on properly implementing equals()and hashCode() methods (utilizing the commons-lang library). So in general, I feel this also helps improving code quality!