Today I updated JOpenShowVar with some neat features compared to how it was before. Check it out on github. The Github readme contains an example of how to use v0.2 and has also an comparison to v0.1.
JOpenShowVar is a TCP/IP interface to KUKA robots written in Java. It allows reading and writing of global variables defined in the KUKA controller.
While JOpenShowVar cannot guarantee real-time access like e.g the KUKA RSI package, it usually returns a call in 3-10 ms.