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Message:

order of object collection

Posted by Jeff Benson on September 22, 1999 at 5:43 PM

The arcticle states that there is no guaranteed order with respect to garbage collection. I was wondering, then, if it safe to utilize a reference to an object that is only referred to by the object being garbage collected within a finalize method.

Consider that object A references object B and object B references object C. B's reference to C is the only reference to C, and A's reference to B is the only reference to B. B becomes eligible for garbage collection because A drops its reference to it. Can B, in its finalize clause, pass its reference to C to another object?

I am concerned that the GC might recognize that the only reference to C is an object that is in the process of being
garbage collected (B), and so might garbage collect it before B is garbage collected.

The reason that I want to do this, is that C represents a resource (database connection) that I have in a pool. If the object using the resource gets garbage collected, I want to return C to the pool.

Jeff