I have a basic Java program with output of "hello world". What I want to do is to write a Java script to run that program and import that into Unity so I can use it in my program in Unity.
Is there a way?
You can communicate with Unity from a Java application trough OSC(Open Sound Control) and send text, commands triggers or load an external file(xml or similar) into Unity.
Unity and Open Sound Control http://www.sundh.com/blog/2012/07/unity-processing-demo/