Most Java implementations are not free software, but for one that is,
have a look at the 'gcj' package, which even compiles to native code!
--
David N. Welton
Consulting: http://www.dedasys.com/
Personal: http://www.dedasys.com/davidw/
Free Software: http://www.dedasys.com/freesoftware/
Apache Tcl: http://tcl.apache.org/