Compared to traditional testing methods like Junit and Jmock, "testing based on sequence diagram" can be more efficiently applied to test the interaction traces between system under test (SUT) and the environment running the SUT. Mock objects come out in order to set up the compatible test environment. Besides that, through the tailor-made mock objects in this project - LiMock, the interaction of different objects within System under test (SUT) becomes possible to be detected to some extent. Although this kind of specific testing method is not considered mature, it would be popular for its easily edited xml input and handy testcase definition. And most important is that the practical interaction can be tested applied anytime during the software development. Case Census-Voter is the demonstated model. It verifies the advantanges of LiMock comparing Jmock and Junit. As a result, it is convienced that sequence based "Java Interaction Test" could present its potential specifically in the area of development of software interaction testing.