Drjava.de:

Drjava.de has 2 URLs listed in 2 Dmoz categories.

Smyle
(Storage That Makes Your Life Easier) An open source hierchical/relational database, seamlessly integrated with Java. [Open Source, GPL]
http://www.drjava.de/smyle/
Top/Computers/Programming/Languages/Java/Databases_and_Persistence/Database_Management_Systems_-_DBMS/Relational

Marvin
Removes unnecessary classes and obfuscates applications, applets, and servlets. Supports encryption of string constants. [Freeware]
http://www.drjava.de/obfuscator/
Top/Computers/Programming/Languages/Java/Development_Tools/Obfuscators