Unit testing is an important part of a programmer’s toolbox and GWT has support built in with its GWTTestCase class. Andrew Glover has written up a nice article on IBM Developerworks on how to unit test your GWT Applications using it. He starts off with a simple GWT example and shows how to refactor it to make it easier to test. Then he describes how to write the test case and run it. It’s a very imformative article.