Alternative multi-threading optimization languages that run on JVM besides Scala?

I am looking for alternatives or competitors to Scala strictly in regards to programmi开发者_开发知识库ng desktop apps on multiple cores. Whether using CPU or GPU cores (ScalaCL), I want to take advantage of all possible multi-threading performance. Scala is definitely a good choice, but I want to know what other options I can pursue. Running on the JVM is key for what I need.

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Clojure is a JVM language designed for concurrency, see: http://clojure.org/concurrent_programming

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You could always use Java with one of the "concurrency" libraries that provide Actor frameworks, STM etc. One that springs to mind is akka (http://akka.io/).

There's also the jCUDA http://www.jcuda.org/ library which might help with your requirement for GPU processing.

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If you like Groovy, you can also check out GPars, which offers Actors as well as Dataflow models.

http://gpars.codehaus.org/