I didn't take a look at Java's weak pointers, but I assume it's same as in 
Smalltalk. 

In Smalltalk a weak pointer is not counted when the garbage checks if the 
object is still referenced. That means if you have only weak pointers to an 
object and the application needs memory it will be garbage collected. 

In Smalltalk theres is a correspinding concept called "finalization". 
If a weak object is garbage collected a finalize message is called. 
This is used in Smalltalk to free external resources like windows. 


Markus
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+----------------------------------------------------------------------------+
| Markus Kohler                          Hewlett-Packard GmbH                |
| Software Engineer                      Network & System Management Division| 
|                                        IT/E Success Team                   |
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