[concurrency-interest]JSR 166 draft API

[Doug Lea]

Eric Crahen wrote:

> When using a barrier like this, I'm not sure I see the value in
> returning an index. I might just be missing something, but the threads
> going into the barrier don't have any influence or clue as to what number
> they'd be assigned. They complete thier work and they get an arbitrary
> number, if used in a loop it could be different each time or it might be
> the same one. So how do you use an unpredictable number effectively?
> 
> Is it more useful than this?
> 
> barrier.sync();
> resultVector.add(result);

Well, maybe not, but it costs nothing to return an index, and allows
people to more easily code existing algorithms. No sense in frustrating
such people for no good reason.

-Doug