Hi All,

We are getting the following exceptions when drools is executing some rules.

Exception:

Caused by: java.lang.NullPointerException

        at org.drools.core.util.LeftTupleIndexHashTable.remove(LeftTupleIndexHashTable.java:251)

        at org.drools.reteoo.NotNode.retractLeftTuple(NotNode.java:226)

        at org.drools.reteoo.SingleLeftTupleSinkAdapter.doPropagateRetractLeftTuple(SingleLeftTupleSinkAdapter.java:217)

        at org.drools.reteoo.SingleLeftTupleSinkAdapter.propagateRetractRightTuple(SingleLeftTupleSinkAdapter.java:124)

        at org.drools.reteoo.JoinNode.retractRightTuple(JoinNode.java:151)

        at org.drools.reteoo.ObjectTypeNode.retractObject(ObjectTypeNode.java:232)

        at org.drools.reteoo.ReteooWorkingMemory$WorkingMemoryReteExpireAction.execute(ReteooWorkingMemory.java:412)

        at org.drools.common.AbstractWorkingMemory.executeQueuedActions(AbstractWorkingMemory.java:1471)

        ... 51 more

Regards,

Mallikarjun K