Bearfruit

Java also has the interesting distinction that it’s basically where all the R&D is happening. Things like Aspect Oriented Programming, bytecode weaving, etc. is being developed in Java pretty exclusively. Not only that, but the universities have been teaching Java for ages, and the Free tools for development are reasonably advanced.

A nice thing for you might be JSR 223. There’s some hooks to let Python scripts run in that, and it gives access to the Java core language classes. Although, I think that the winner there will be JavaScript, since Rhino is included in J2RE 1.6. What’s interesting there is that you can then rapidly prototype some code in JavaScript (or Python). If it’s too slow, you can compile it. If that’s still too slow, you can refactor bits into Java and just call those from the scripting language.