I asked a question earlier about which language to use for an AI prototype. The consensus seemed to be that if I want it to be fast, I need to use a language like Java or C+
You can build your program in one of the higher level languages for example Python or Ruby and then call modules that are compiled in the lower level language for the parts you need performance. You can choose a platform depending on the lower level language you want.
For example if you want to do C++ for the speedy stuff you can just use plain Python or Ruby and call DLLs compiled in C++. If you want to use Java you can use Jython or one of the other dynamic languages on the Java platform to call the Java code this is easier than the C++ route because you've got a common virtual machine so a Java object can be used directly in Jython or JRuby. The same can be done on the .Net platform with the Iron-languages and C# although you seem to have more experience with C++ and Java so those would be better options.