Thank you all for the congratulations.
Actually I have started to work on the assignment on April, this year. But because of a job change, I didn't have the time to finish it in a reasonable time and resulted in a long dead period. So its not relevant in my case, I guess.
I have started the project with the development of the database. It was the module that got a lot of JUnit and multithreading tests. Mainly I wanted to be sure it is free of deadlocks.
Then I have developed the network server using RMI (I have used rmic to compile the stubs), then the network client and the GUI. For the other parts of the project I didn't write JUnit tests, as they seemed too simple to me to get JUnit tests. But that wouldn't have hurt, that's for sure.
Architecturally speaking, I have used the Factory pattern to get a local or remote implementation of the main business interface. In this interface I have used the facade pattern to access the database. And I have used once again the facade pattern for the network implementation.