ConcurrentModification in UnifiedLoaderRepository3 packagesMap -------------------------------------------------------------- Key: JBAS-6381 URL: https://jira.jboss.org/jira/browse/JBAS-6381 Project: JBoss Application Server Issue Type: Bug Security Level: Public (Everyone can see) Components: ClassLoading Affects Versions: JBossAS-4.2.3.GA Reporter: Adrian Brock Assignee: Scott M Stark The UnifiedLoaderRepository3 has an internal packagesMap which is currently a ConcurrentHashMap<String, TreeSet<UnfiedClassLoader>> where the TreeSet uses a comparator based on the PkgClassLoader/UnifiedClassLoader order. This TreeSet is not properly synchronized against changes, e.g. (un)deployment of a classloader that has a certain package while somebody is trying to load a class from that package. This can lead to a java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(HashMap.java:841) at java.util.HashMap$KeyIterator.next(HashMap.java:877) at java.util.AbstractCollection.addAll(AbstractCollection.java:318) at java.util.TreeSet.addAll(TreeSet.java:258) at org.jboss.mx.loading.UnifiedLoaderRepository3.getPackageClassLoaders(UnifiedLoaderRepository3.java:246) at org.jboss.mx.loading.LoadMgr3.beginLoadTask(LoadMgr3.java:178) at org.jboss.mx.loading.RepositoryClassLoader.loadClassImpl(RepositoryClassLoader.java:514) at org.jboss.mx.loading.RepositoryClassLoader.loadClass(RepositoryClassLoader.java:408) Rather than synchronizing the TreeSet, I'd suggest using a CopyOnWriteList whose contents are presorted like the TreeSet. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira