On Tue, May 8, 2012 at 7:12 PM, Marius Dumitru Florea
<mariusdumitru.florea(a)xwiki.com> wrote:
Hi Fabio and devs,
I found a serious concurrency issue in the REST server module while
debugging the instability of the Extension Manager when
extensions.xwiki.org repository is used (default case) . The Extension
Manager UI searches extensions using REST and very often it gets 500
HTTP response code. See
http://jira.xwiki.org/browse/XWIKI-7773 for
instance. The server log from
xwiki.org shows that the real cause is:
May 8, 2012 5:09:14 PM org.restlet.engine.application.StatusFilter doHandle
WARNING: Exception or error caught in status service
java.util.ConcurrentModificationException
at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372)
at java.util.AbstractList$Itr.next(AbstractList.java:343)
at org.xwiki.rest.XWikiSetupCleanupFilter.afterHandle(XWikiSetupCleanupFilter.java:73)
See the full stacktrace
http://pastebin.com/hnFSuwem .
The problem is related to the way "releasable components" are managed.
I debugged locally both XWikiSetupCleanupFilter [1] and
ComponentsObjectFactory and here's what I discovered:
* org.restlet.Context.getCurrent() is shared across HTTP requests