Your objective as a player in CodeRuler is to write Java code that simulates the ruler of a medieval kingdom. The new CodeRuler is now supported o­n Eclipse v3.0 (CodeRuler no longer works with Eclipse 2.x). Tournament results are also now listed in text, XML, and HTML. Various other bug fixes and improvements have been added.

More details are avialable here [1] and at the following link:
http://www.alphaworks.ibm.com/tech/coderuler?open&S_TACT=104AHW61&S_CMP=GR&ca=dgr-eclpsw02awcoderuler