For testing we mainly used System.err.println functions. Some black box tests were writen, but due to some conceptual changes of the classes, we found it very hard to keep the black box tests in sync. Seen in this light we think it would be very helpful to have some kind of preprocessor facilities.
An overview of the spots, were you can find our black box tests:
We believe that for writing a complete black box test for our game you would need a second team.