[Advanced-java] JNI problem

[sumit@xxxxxxxxxxxxxxx (Indoria, Sumit (GMI NY - GDA))]

Hi!

I am having trouble doing some memory management in JNI, any ideas would be helpful.

Here is the structure

public class A
{
	public A()
	{
		_jni_initialize(); // allocates a native instance of class A
	}

	protected void finalize()
	{
		_jni_delete();
	}

	private native _jni_initialize(); // allocates native C++ instance
	private native _jni_delete()

	private transient long Cinstance; // holds the memory address of the native C++ instance
}

public class B
	extends A
{
	public B()
	{
		_jni_initialize(); // allocates a native instance of class B
	}

	protected void finalize()
	{
		_jni_delete();
		supre.finalize();
	}

	private native _jni_initialize(); // allocates native C++ instance
	private native _jni_delete()

	private transient long Cinstance; // holds the memory address of the native C++ instance
}


Now when i construct a B object, the A constructor is also called being a super class, and I have a native instance of both A and B allocated . Well conceptually when the finalize() method is called
on B , it should also call finalize() on the super A() and delete any native instance allocated, but this is where it fails, the B object gets deleted on the finalize call, but when I step through the
_jni_delete() of the class A, it has no idea about the native object created , when the constructor for B was called, so it basically returns me a null pointer exception. Any ideas why this behaviour
is occuring and any solutions to it.
(I tried a dirty solution of creating a dummy A constructor which does not allocate a native instance, and that works, but this seems really dirty... )

Thanks for your help.

Sumit