Code Review 6967684: httpserver using a non thread-safe SimpleDateFormat

[Chris Hegarty]

Michael,

CR 6967684: httpserver using a non thread-safe SimpleDateFormat

Bug description says it all. I guess in reality this may have gone 
unseen for so long because, if two or more threads were servicing 
requests the dates they would be generating should be fairly similar, 
but worst case they could actually see partial of corrupt dates. This 
bug causes random httpserver tests to fail when run with assertions enabled.

The most reasonable solution is to use a thread-local instance of the 
formatter, rather than creating one per request.

Webrev:
   http://cr.openjdk.java.net/~chegar/6967684/webrev.00/webrev/

Thanks,
-Chris.