This is an old university project with the goal to create a simple bridge between the Java language and R.
Existing interfaces like rJava had insufficiences at that time, mostly like requiring DLL dependencies.
The project was designed with extensibility in mind, so that various implementations of the actual conversation between R and Java are possible. We orginally thought of socket or simple CLI communication and implemented the latter in a very simple way, which works but can of no means be considered stable.