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What is a Singleton Class?

 
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please anybody explain about singleton class
[ April 11, 2005: Message edited by: Barry Gaunt ]
 
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as far as I know sigleton is the methodology which states the mechanizm where ONLY one instance of the certian class is maintained throught the program execution
[ April 10, 2005: Message edited by: levani dvalishvili ]
 
nagaraj reddy
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what you told about singleton class is correct.Please explain through the code.


thanks in advance
 
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not scjp

try design forums instead, do your own homework. There's tons of resources available explaining in fine detail what a singleton is.
 
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Transferring to ...
 
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A Singleton is a class that can only be instantiated once, it's an OOP substitute for global variables. There are two basic idioms for this, eager instantiation and lazy instantiation. I'm writing this code from memory, the bugs are left as an exercise for the reader.


[ April 11, 2005: Message edited by: peter wooster ]
 
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See http://faq.javaranch.com/view?SingletonPattern
 
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Originally posted by Ilja Preuss:
See http://faq.javaranch.com/view?SingletonPattern



A singleton is a class of which there cannot be multiple instances.



Is the above correct ? I think GoF states that the pattern can control the number of instances and it could be more than 1.
 
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