I have held this entry in draft so long that it may be hard for me to convey the spirit of this issue. So there's all this open source, free code for people to take advantage of and contribute to, but alas, it is ultimately resting upon a foundation that mars that freedom. That foundation, the Java(TM) Runtime Environment, and the Java(TM) Development Kit (JDK), is no small thing; replacing it, or implementing an equivalent foundation in free or open source software is a mammoth task. So, what are we to do? Should we throw up our hands in despair, declare c'est la vie and have another latte?
No. Enter the free runtimes movement. There are a body of open source/free software advocates and developers who have taken on this task, and they have made some quite impressive progress. Projects like Kaffe, GNU Classpath, SableVM, JamVM have taken up the gauntlet, and things are coming along nicely. I regularly compile against these virtual machines and runtime environments and I am amazed at what I find.
I remember the first time I heard a discussion about an open source Java(TM) implementation. The concept was being scoffed at during the time when IBM was calling for Sun to make Java(TM) open source. It was at my local Java(TM) User Group meeting; almost nobody was in favor of the idea of Java(TM) going open source. The Java(TM) community has this strange, dysfunctional relationship with open source. They love to consume, utilize, and demand more from open source, yet the idea of giving back to it or supporting a completely free implementation turns them off. Weird.
Like it or not, free runtimes are a reality, and they are gaining ground on the closed, proprietary implementations. The proven model of bazaar development is yielding some pretty impressive results. If you are into the geek thing, and if you admire the innovations of the computing era like GNU/Linux, Apache, etc. well, guess what? This is the new frontier, kiddo. Want to make your mark? Join us.