ClassCastException in mvel when updating a List property with modify

Solution In Progress - Updated -


Rules that used "modify" that worked perfectly in BPM Suite 6.4 fail in RHPAM 7.4

We are upgrading from JBoss BPMS 6.4.11 to RHPAM 7.4.0. We have run the migration script and most of our rules work fine.

However we are unable to execute rules with the following pattern:

rule "Update address list"
    dialect "mvel"
                $p : Person()
                not(Address(street=="Main Street") from $p.addresses)
                Address address = new Address("Main Street")
                modify($p) { addresses.add(address) }


Exception executing consequence for rule "Update address list" in defaultpkg: java.lang.ClassCastException: org.mvel2.optimizers.impl.refl.nodes.GetterAccessor cannot be cast to org.mvel2.optimizers.impl.refl.nodes.MethodAccessor
    at org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(
    at org.drools.core.common.DefaultAgenda.handleException(
    at org.drools.core.phreak.RuleExecutor.innerFireActivation(
    at org.drools.core.phreak.RuleExecutor.fireActivation(
    at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(
    at org.drools.core.concurrent.AbstractRuleEvaluator.internalEvaluateAndFire(
    at org.drools.core.concurrent.SequentialRuleEvaluator.evaluateAndFire(
    at org.drools.core.common.DefaultAgenda.fireLoop(
    at org.drools.core.common.DefaultAgenda.internalFireAllRules(
    at org.drools.core.common.DefaultAgenda.fireAllRules(
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.internalFireAllRules(
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(
    at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(
    at org.drools.compiler.integrationtests.Misc2Test.testModifyAddToList(


  • Red Hat Process Automation Manager (RHPAM)
    • 7.x
  • Red Hat Decision Manager (RHDM)
    • 7.x

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