Yeah, I wrote that and recently found out the reasons why it's faulty -- stupid memory model :)
Can you file a bug on this? -Pat -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Micha³ Mosiewicz Sent: Tuesday, October 07, 2003 4:01 AM To: opensymphony-webwork Subject: [OS-webwork] Bug catching contest... This code won't work as you would expect. It's that kind of bug you wouldn't expect, but also that kind that should be taught on every programming course (rare). For those who are impatient and don't want to find out why it won't work I suggest googling for "double checked locking" or DCL. Due to java memory model (as matter of fact it's not only java) the code below doesn't work. I strongly suggest to pass xwork/webwork through checkstyle. I suppose there might be more. Of course - in this place it doesn't really matter if it synchronized or not - it's just a matter of optimisation. But the same idiom might be multiplied. OgnlUtil.compile(): public static Object compile(String expression) throws OgnlException { Object o = null; o = expressions.get(expression); if (o == null) { synchronized (expressions) { o = expressions.get(expression); if (o == null) { o = Ognl.parseExpression(expression); expressions.put(expression, o); } } } return o; } -- Mike ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Opensymphony-webwork mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/opensymphony-webwork ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. SourceForge.net hosts over 70,000 Open Source Projects. See the people who have HELPED US provide better services: Click here: http://sourceforge.net/supporters.php _______________________________________________ Opensymphony-webwork mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/opensymphony-webwork
