Does anybody have any experience in resolving this:

Some background: I am trying to retract a fact and before doing that, I checked the object and make sure it is not null. But still, I got null pointer exceptions.

A previous developer working with me had posted the problem in Jan 2009. Apparently, there is no final answer in that thread. Here is the old thread: http://lists.jboss.org/pipermail/rules-users/2009-January/007555.html

This is my exception:

####<Mar 11, 2010 9:16:24 AM EST> <Error> <HTTP> <epsdatbeal25> <cla-01> <[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1268316984268> <BEA-101017> <[weblogic.servlet.internal.WebAppServletContext@22fed98 - appName: 'cla', name: 'cla.war', context-path: '/cla-web'] Root cause of ServletException.

java.lang.NullPointerException

                at org.drools.util.RightTupleIndexHashTable.remove(RightTupleIndexHashTable.java:224)

                at org.drools.reteoo.JoinNode.retractRightTuple(JoinNode.java:204)

                at org.drools.reteoo.ObjectTypeNode.retractObject(ObjectTypeNode.java:210)

                at org.drools.reteoo.EntryPointNode.retractObject(EntryPointNode.java:190)

                at org.drools.common.AbstractWorkingMemory.retract(AbstractWorkingMemory.java:1078)

                at org.drools.common.AbstractWorkingMemory.retract(AbstractWorkingMemory.java:1045)

                at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

                at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)

                at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)

                at java.lang.reflect.Method.invoke(Method.java:585)

                at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:301)

                at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:198)

                at $Proxy42.retract(Unknown Source)

Thank you so much!

- Eugene


Eugene Hsiang
Application Architect
Reston Office

The College Board

11955 Democracy Drive

Reston, VA 20190-5662

571-485-3356 (office)

703-796-0817 (Fax)
ehsiang@collegeboard.org
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