Thanks to all the reviewers who were too polite to say: """What was Martin thinking?"""
For some reason I had imagined that Math.random() was itself synchronized. After editing, I have a very small change that is hardly worth doing except that I already have a webrev. http://cr.openjdk.java.net/~martin/webrevs/openjdk7/Math.random/ Martin On Sat, Jun 5, 2010 at 07:00, Eamonn McManus <eamonn.mcma...@sun.com> wrote: > It seems to me that if two threads call this Math.random() at the same time > then two instances of Random() can be constructed. That contradicts the > specification of the method, and is theoretically observable because the two > values from Math.random() will typically not be a pair of values that could > have been returned from consecutive calls to nextDouble() on a single Random > instance. Granted, the chances of this actually mattering are infinitesimal, > but I think the performance gain of avoiding a synchronized method only on > the very first call to Math.random() is infinitesimal too. So I'd be > inclined to leave well enough alone here. > Eamonn > > Martin Buchholz wrote: >> >> Here's an optimization for Math.random() that appears to be safe, >> despite the double-check access: >> >> http://cr.openjdk.java.net/~martin/webrevs/openjdk7/Math.random/ >> >> David, if you agree, could you file a bug? >> >> Thanks, >> >> Martin >> >
