InfoQ Article: Deploying Java Apps on Fedora Core
gcj aims to implement a complete system, compatible with Java, centered around an ahead-of-time compiler. It has a cleanroom class library based on GNU Classpath, and a built-in interpreter. The compiler can compile Java source files, class files, or even entire jar files to object code.Read Delivering Java Apps on Fedora Core.
In recent related news, a plan to use the Eclipse compiler as the new gcj front end was approved on June 6th. Also on April 17th, Tom Tromey has announced the availability of two experimental Just-In-Time (JIT) interpreters for GCJ based on libjit and LLVM respectively.