Java
Java is an object oriented programming language that can be executed in a platform independent manner via generated byte-code.
Availability on LRZ's HPC platforms
The OpenJDK can be loaded through an appropriate environment module:
module load openjdk
Add-ons
JNA (Java Native Access) allows other programming languages to interoperate with Java. The interface maps to the (platform-specific) C ABI.
Documentation
Please consult the Java documentation on Oracle's web site (look up the "Java" entry in the linked page).
JNA has its own documentation page (it is not directly supported by Oracle).