There is a clear need for an open-source version of Java 2, Standard

Edition (J2SE) runtime platform, and there are many ongoing efforts

to produce solutions (Kaffe, Classpath, etc). There are also efforts

that provide alternative approaches to execution of Java bytecode

(GCJ and IKVM). All of these efforts provide a diversity of

solutions, which is healthy, but barriers exist which prevent these

efforts from reaching a greater potential.