C++ to Java using JNI

I have a C++ program that has a pointer that is a reference to an image. I need to pass the pointer to a java program so that I can perform processing on the image. What I am finding is that calling C++ from Java is not a problem, but this has me stumped.. Does anyone have any examples of a C++ program calling Java??
[ September 17, 2007: Message edited by: PJ Crump ]

Before your C++ program can call Java, you have to have a JVM running.

To run a JVM, use the Java Invocation API. In that same API are C++ functions for loading Java classes, finding methods, creating objects, invoking methods etc.