RFR: 8087322: Implement a Semaphore utility class

[Kim Barrett]

On Jun 25, 2015, at 12:42 PM, Stefan Karlsson <stefan.karlsson at oracle.com> wrote:
> 
> Hi all,
> 
> Updated webrev:
> http://cr.openjdk.java.net/~stefank/8087322/webrev.05.delta
> http://cr.openjdk.java.net/~stefank/8087322/webrev.05

One minor thing that I unfortunately forgot to include in previous comments:

I think Semaphore::_impl should be private, not protected.  I don’t need a new webrev if you want to fix that.

Looks good otherwise.