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Subject: Re: Volatile happens before question
Date: Wed, 18 Jan 2012 16:10:18 -0800
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On 1/18/2012 3:30 PM, raphfrk@gmail.com wrote:

> However, if the .get() gets the old value then it isn't guaranteed to
> happen before the increment, i.e. there is no guarantee.


If you get the old value, then no writes have occurred.  We're talking 
AtomicInteger::get() here, right?  Not Map::get() or something.


Thread 1                        Thread 2
Writer                          Reader

map.put() // write
writeCounter.increment() -----> writeCounter.get() // happens before
                                 map.get()          // read

                          -----> writerCounter.get() // happens before
                                 map.get()