From: Greg Barton <greg_barton(a)yahoo.com&gt; Subject: [rules-dev] NPE in AbstractWorkingMemory.update To: "Rules Dev List" <rules-dev(a)lists.jboss.org&gt; Date: Wednesday, May 27, 2009, 1:25 AM At seemingly random times I'm getting this exception: Exception in thread "Thread-5" java.lang.NullPointerException         at org.drools.common.AbstractWorkingMemory.update(AbstractWorkingMemory.java:1387)         at org.drools.common.AbstractWorkingMemory.update(AbstractWorkingMemory.java:1350)         at org.drools.concurrent.UpdateObject.execute(UpdateObject.java:46)         at org.drools.concurrent.CommandExecutor.run(CommandExecutor.java:78)         at java.lang.Thread.run(Thread.java:619) I've only gotten the exception when using StatefulSession.asyncUpdate() from a separate thread.  AbstractWorkingMemory.java:1387 is wrapped in an if statement that checks whether maintainTms==true, so setting that to false has apparently avoided the problem. (Can't be 100% sure, but it has been runnign for a few hours without exception.) The FactHandles I'm passing in to StatefulSession.asyncUpdate() are never null, so I can only guess that InternalFactHandle.getEqualityKey() is sometimes returning false. Do you want a JIRA on this?  I can't recreate it reliably.       _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev