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JAVA JNI C Debugger

Is there any debugger that helps debug a Java JNI program along with the C library?

I should be able to debug the program starting from static void main in Java and continue to debug and place break points in the native c function and then continue to debug in Java after the control is transferred from C to Java.

Solution

  • A Java Virtual Machine debugger is very different from native code debugger. There is currently no such MATURE solution as one and the same debugger which would be able to seamlessly step from Java to native code and back. While this is a very irritant problem which makes some smart people trying to develop such a solution, there is undoubtely tons of un-imaginable problems involved. I personally do it in the following way:

    1. start your Java code in debug mode and put a breakpoint at the first native call you are interested in. You can even implement a static native call, which won't do anything significant but will enable you to break as soon as possible.
    2. fire up a native debugger. This absolutely can be the same instance of Eclipse, given two prerequisities: you have CDT installed and your native code was compiled in a way, that the debugging info is understood by CDT. Attach to the java(w.exe) process running your Java code. Put a breakpoint in the native code.
    3. Whenever you need to transition over JNI interfaces, put breakpoints as close to the call entry/exit as you can (or need).