GNUBridge is a Contract Bridge program written in Java and available under GNU public license v. 3. My fork enhances its strength of bidding, yet it's not complete. Only Opening - Response - Rebid - Partner's Rebid are implemented, and after this process, the program will bid a PASS.
Note, this is not the official version of GNU Bridge. But the playing is still the original Double-Dummy solver. You can download a runnable jar file here: http://bbs.fishc.com/thread-51511-1-1.html
##Implemented or Partly Implemented Conventions Stayman, Minor Suit Stayman, Two-over-One Game Forcing, Jacoby Transfer, Forcing 1NT, Inverted Minor, Takeout Double, Weak Two, Preempt
##Users: Official Version Download from homepage: gnubridge.org
##Developers You can use command-line git and ant to build the project, or Eclipse with EGit.