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Static synchronization vs instance var synchrnisation  RSS feed

 
navi shrav
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hi all,
can anybody help me understand as to how a static variable is synchronized verses an instance variable or the difference in the two.
thanks in advance.
 
Anthony Villanueva
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Hi Navi, variables can't be directly synchronized. Only methods and code blocks can be synchronized. Please see the Sun tutorial on synchronization.
 
Ron Newman
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It is, however, possible for static methods to be synchronized -- the lock lives in the Class object.
 
Ilya PA
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Hi Navi,
Actually as far as i know you can synchronize a variable. U can do that placing the 'volatile' keyword before a variable's name. This is often used with variables of size bigger then a CPU word size. For example normal PIII word size is 32bits, but variables of type long and double are 64bit vars. So when one thread loads a part of a long var to the cpu(first 32bits), another thread should not be able to access that variable.
 
Leslie Chaim
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Yes but as noted in a rather heated debate over the Behaviour of Volatile variables you will see how Peter Haggar lays out the facts
 
Jim Baiter
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If you're talking about synchronizing static methods there is a difference. In this case the class lock is acquired whereas with the non-static method the object lock is acquired.
 
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