java.lang.UnsupportedOperationException while persisting Drools session

[Bishnu Shankar Pandey]

I am using Drools version 7.15.0.Final. I am getting an exception when I am trying to persist drools session. Below is the stack trace of the exception. Can anyone help me with this issue?

java.lang.UnsupportedOperationException
    at org.drools.core.common.SingleBetaConstraints.getOriginalConstraint(SingleBetaConstraints.java:209)
    at org.drools.core.reteoo.BetaNode.writeExternal(BetaNode.java:256)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.SingleLeftTupleSinkAdapter.writeExternal(SingleLeftTupleSinkAdapter.java:75)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.LeftTupleSource.writeExternal(LeftTupleSource.java:110)
    at org.drools.core.reteoo.LeftInputAdapterNode.writeExternal(LeftInputAdapterNode.java:134)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.SingleObjectSinkAdapter.writeExternal(SingleObjectSinkAdapter.java:50)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.ObjectSource.writeExternal(ObjectSource.java:118)
    at org.drools.core.reteoo.AlphaNode.writeExternal(AlphaNode.java:102)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.util.ObjectHashMap$ObjectEntry.writeExternal(ObjectHashMap.java:181)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1378)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.util.AbstractHashTable.writeExternal(AbstractHashTable.java:90)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.CompositeObjectSinkAdapter.writeExternal(CompositeObjectSinkAdapter.java:89)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.ObjectSource.writeExternal(ObjectSource.java:118)
    at org.drools.core.reteoo.ObjectTypeNode.writeExternal(ObjectTypeNode.java:232)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at java.util.concurrent.ConcurrentHashMap.writeObject(ConcurrentHashMap.java:1413)
    at sun.reflect.GeneratedMethodAccessor58.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1128)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.EntryPointNode.writeExternal(EntryPointNode.java:138)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.ObjectSource.writeExternal(ObjectSource.java:120)
    at org.drools.core.reteoo.ObjectTypeNode.writeExternal(ObjectTypeNode.java:232)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.ObjectSource.writeExternal(ObjectSource.java:120)
    at org.drools.core.reteoo.AlphaNode.writeExternal(AlphaNode.java:102)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.ObjectSource.writeExternal(ObjectSource.java:120)
    at org.drools.core.reteoo.AlphaNode.writeExternal(AlphaNode.java:102)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.LeftInputAdapterNode.writeExternal(LeftInputAdapterNode.java:135)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.AbstractTerminalNode.writeExternal(AbstractTerminalNode.java:76)
    at org.drools.core.reteoo.RuleTerminalNode.writeExternal(RuleTerminalNode.java:161)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeArray(ObjectOutputStream.java:1378)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1174)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at java.util.HashMap.internalWriteEntries(HashMap.java:1790)
    at java.util.HashMap.writeObject(HashMap.java:1363)
    at sun.reflect.GeneratedMethodAccessor55.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:1128)
    at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1496)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1432)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.reteoo.ReteooBuilder.writeExternal(ReteooBuilder.java:461)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at org.drools.core.impl.KnowledgeBaseImpl.writeExternal(KnowledgeBaseImpl.java:565)
    at java.io.ObjectOutputStream.writeExternalData(ObjectOutputStream.java:1459)
    at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1430)
    at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1178)
    at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
    at com.test.SessionRepository$.saveSession(SessionRepository.scala:29)

The above exception is very random. Sometimes the same code works perfectly fine but when after when I get this exception I am not able to persist the session.

Thank  you,

Regards,

Bishnu