Difference between static class and singleton?

Hi I wonder what could be the difference between static methods and singleton?
In singleton at any point of time there will be only one object existing in the JVM. We create singleton to avoid multiple object creation for that class.
If I make all the methods in the class as static also it does the same job. The memory will be allocated once. Even there wont be any object in this case, so time required for object creation also can be saved. looks like more efficient but still why need singleton?
This question is also posted in java programming forum. The thread is as follows:-
[Click on this to visit that thread |http://forum.java.sun.com/thread.jspa?threadID=5278517&tstart=0]
Edited by: murrayb9654 on Mar 25, 2008 8:20 AM

yawmark wrote:
Static class is a realization of singleton pattern.Not in any conventional sense.
~Especially since a static class is completely different from a class with all static methods.

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Moderator message: what is the difference between your question and a question that we'd welcome here in the forums?
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Edited by: Thomas Zloch on Nov 22, 2010 1:17 PM

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Moderator message: what is the difference between your question and a question that we'd welcome here in the forums?
[Rules of engagement|http://wiki.sdn.sap.com/wiki/display/HOME/RulesofEngagement]
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