Now that's what I call instant gratification. If you just pick a class and test, Jtest will perform static analysis and white box testing automatically. Black box testing requires a bit more interaction. Static analysis Static analysis allows you to set up a number of rules and apply them to your code. When Jtest runs, it marks all variables that violate the rules as errors.
Rules can be much more complicated, of course.
Rules can test code for anything from simple conformance to naming conventions to the proper use of inner classes and method declaration rules. In all, Jtest ships with 174 built-in rules. Click on thumbnail to view full-size image. The rules aren't arbitrary. They're based on well-documented Java test practices.