Synchronized keyword for simple addition

Hi, I have a function, as given below
{noformat}public static void increment() {{noformat}{noformat} a = a + 1; {noformat}{noformat}}
{noformat}
This function will be called from multiple threads (a is also a static variable).
My question is should I use "synchronized" keyword for this method to avoid unpredictable results? Is there a way to wirte this function without using "synchronized" keyword?
Please suggest.

Thanks, jwenting. I wanted to confirm that "synchronized" has to be used.
jwenting wrote:
yes. Depending of course on what you decide to be "unpredictable" :)you understand what "unpredictable" means here ;)
jwenting wrote:
yes, don't use a static variable but a method local one. Of course that will have a totally different effect.Variable "a" should be a class level variable. Yes, local variable has a totally different effect. ;)

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but I think that synchronized keyword in this code
doesn't have an effect, i.e., if we remove it, the
output would be ok,Well, you're mistaken.
can anyone able to change this
code such that the output becomes different depend on
existance of synchronized keyword.No change is necessary. Synchronization is required to ensure proper behavior for the code presented.

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Synchronized keyword for simple addition

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