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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: Using Enumerated Types as Array Indexes
Date: Sat, 20 Aug 2011 00:20:02 +0200
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On 19.08.2011 22:05, Andreas Leitgeb wrote:
> Robert Klemme<shortcutter@googlemail.com>  wrote:
>> All solutions to fix remainder into modulo but keep the wrap around
>> which have been proposed so far share a common disadvantage: if the
>> number range is not a multiple of the divisor the value distribution
>> will not be uniform.
>>
>> The solution I used to fix this employed a do while loop and
>> compareAndSet() to reset the value to the beginning of the range (0 in
>> this case) in a thread safe manner.
>
> There's a much simpler "meta-way" to fix it:  just stick to powers of
> 2 for the array length - then the overflow *does* always happen at a
> multiple of the divisor and the value distribution uniform :-)

I reckon you do not mean that suggestion serious.  Just in case: 
limiting to powers of 2 was not an option here.  And if it was, I would 
not have used modulo or AtomicInteger's features but just used binary & 
to cut off leading bits.

Kind regards

	robert

-- 
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