To run this game from the source code, you must have the java JDK installed You can get download and install the java JDK from here: http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html
You must also add the jdk to your ENVIRONMENT path, enabling you to execute the command "javac" from the command line. Here's a guide for windows: https://www.youtube.com/watch?v=58ZO_NaAOfU
Please send me an email if you need help doing any of this. I will occasionally compile the code myself and post executables so you don't have to