I guess that would depend on your definition of "singleton".
If you defer object creation to some mechnism external to the "singleton" class, you could let that mechanism cache the first instance it creates and have it return that instance upon consecutive calls. Which is kind of how Spring handles "singleton" beans. Ofcourse this definition of a "singleton" is radically different from the traditional design
pattern, and ouside the scope of such a mechanism the bean could not be considered a "singleton" at all.
[ June 05, 2008: Message edited by: Jelle Klap ]
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