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Behaviour of WeakHashMap

Gopal Shah
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Joined: May 17, 2003
Posts: 65
Hi Friends,
Suppose we r running low of memory, then what happens to the mappings of WeakHashMap object. Are all the keys (mappings) removed or only few keys (equivalent to the amount of memory req.) are GC.
If later one is true, then on what basis the object for GC is chosen ? FIFO, LIFO or some other algo.
Thanks in advance.
Gopal Shah
Sumitro Palit
Ranch Hand

Joined: Dec 13, 2003
Posts: 37
I think when garbage collection kicks in, its going to clear as many weak references (keys) it can, normally won't do it selectively like using a FIFO/LIFO algorithm. So if you are implementating a caching mechanism using a WeakHashMap dont rely on such behavior.
Checkout this article for details:
http://www.onjava.com/pub/a/onjava/2001/07/09/optimization.html
Cheers,
-ortimus
 
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subject: Behaviour of WeakHashMap