From your description, it seems you care less about the actual count of references than to simply know when an object has been collected. If this is the case, you can use WeakReference
or PhantomReference
to determine when a referenced object is ready for finalization.
See:
- Javadoc for
WeakReference
: http://download.oracle.com/javase/6/docs/api/java/lang/ref/WeakReference.html - Javadoc for
PhantomReference
: http://download.oracle.com/javase/6/docs/api/java/lang/ref/PhantomReference.html - A great explanation of weak references: https://community.oracle.com/blogs/enicholas/2006/05/04/understanding-weak-references
- Garbage collector callbacks: http://java.dzone.com/articles/letting-garbage-collector-do-c
- Garbage collection notification?