Okay, this is not really a question, but I wanted to show you a prototype I made today to connect Java and Lua.
You'll need Java 8 to be able to run it and you can find releases on https://github.com/skiwi2/JavaLuaInteropTest/releases
Example screenshot:
It technically works by compiling the Lua code you type there to Java bytecode, and then calling the "applyFunction" function on that.