On 4/25/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
Author: jmsnell
Date: Wed Apr 25 07:46:17 2007
New Revision: 532373
URL: http://svn.apache.org/viewvc?view=rev&rev=532373
Log:
Second attempt at improving thread safety on ExtensionFactoryMap. Wrap the
weakhashmap with a synchronized map and synchronize the
iterations over the factories list
Other potential issues in this code WRT thread safety:
We don't make a defensive copy of the factories list when we're
created, so potentially someone else can synchronize on it, resulting
in deadlock. Alternatively it could be modified without
synchronization after we're created, defeating the purpose of the
other locking we do. Similarly, we return a reference to it in
getFactories(), with identical potential badness.
The first case can be dealt with via documentation if we don't want to
make a copy, but the second really seems like it should be dealt with
by making a copy of the list before returning it.
-garrett
