https://issues.apache.org/bugzilla/show_bug.cgi?id=49972
--- Comment #3 from Chuck Caldarale <chuck.caldar...@unisys.com> 2010-09-22 10:20:36 EDT --- (In reply to comment #2) > It looks scarier than that. > In short, see > http://www.cs.umd.edu/~pugh/java/memoryModel/DoubleCheckedLocking.html Not all double-checked locking is evil. The simple fix is to just reverse these two lines: currentDateGenerated = now; currentDate = format.format(new Date(now)); By setting currentDate prior to currentDateGenerated, the potential of returning null is eliminated, and unnecessary locking is still avoided. (This is in addition to making the field private, as Sebb noted.) Case 2 is not a problem; the Java language spec requires operations to be visible to other threads in program order, so the all operations for building the new formatted String must be complete before the reference to it is stored in the field. - Chuck -- Configure bugmail: https://issues.apache.org/bugzilla/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug. --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org
