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garbage collection

Shashank Gokhale
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Joined: Jan 07, 2003
Posts: 92
Hi all,
I was reading through the Sun tutorials, and it does say that if all the references to an object are set to null, then the object is eleble for garbage collection. But the following confuses me. Its Question #2, and my question is this, if point is set to null, does that not mean that the object that point refers to is now eligible for garbage collection?

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Chad McGowan
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Joined: May 10, 2001
Posts: 265
No, because the Rectangle still holds a reference to the Point object. If the rectangle reference was also set to null, both objects would become eligible for gc.
Barry Gaunt
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Joined: Aug 03, 2002
Posts: 7729
Chad's correct, you must examine the Rectangle class' code. You can see that the reference to the Point instance passed as a parameter is stored in the instance variable origin. So the Rectangle instance holds on to the Point instance preventing it from becoming eligible for garbage collection.

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Shashank Gokhale
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Joined: Jan 07, 2003
Posts: 92
Oh yes,
Thanks I see it. I guess I didnt follow the program too closely. My bad
I agree. Here's the link:
subject: garbage collection
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