JNsAutoreleasePool
Holy crap, is this a specialised piece of code. Suppose you have a Java project with JNI components. Suppose those JNI components interact with libraries written in Objective-C. Suppose further that those ObjC libraries assume that their parents will handle basic infrastructure such as NSAutoreleasePools, etc. But the parents don't provide this infrastructure because they aren't ObjC libraries themselves. Perhaps they were written in C or C++. And they are interfacing with normal C-like functions in your Objective-C code.
So you need a way to add this infrastructure so that you don't get memory leaks. Enter JNsAutoreleasePool. Put this object at the beginning of a Java thread which will interact with ObjC code, and move on with life.