Accumulate Function ClassCastException

[Eugene Shvartsman]

I am getting a ClassCastException with the following LHS side of the rule. The sample I am posting is the simplest version of the rule that I could create while still retaining the error. 

when

$employee : Employee () 

$contractLine : MinMaxContractLine( contractLineType == ContractLineType.HOURS_PER_DAY, $maxMinutesValue : maximumValue, $weight : maximumWeight, 

maximumEnabled == true)

$info : EmployeeRosterInfo( $type : profileDayType, $firstDayOfWeek : firstDayOfWeek )

$shiftDate : ShiftDate(isInPlanningWindow($info))

accumulate ( $shift : ShiftAssignment( employee != null, employee == $employee)

           ,$minutesInDay  : sum($shift.getShiftDurationMinutesByProfileType($type, $shiftDate));

            $minutesInDay > 0

)

then

During the execution of the rules I get the following stack trace:

java.lang.RuntimeException: java.lang.ClassCastException: com.x.engine.domain.ShiftDate cannot be cast to com.x.engine.domain.dto.ProfileDayType

at org.drools.core.rule.SingleAccumulate.accumulate(SingleAccumulate.java:90)

at org.drools.core.phreak.PhreakAccumulateNode.addMatch(PhreakAccumulateNode.java:759)

at org.drools.core.phreak.PhreakAccumulateNode.doLeftInserts(PhreakAccumulateNode.java:163)

at org.drools.core.phreak.PhreakAccumulateNode.doNode(PhreakAccumulateNode.java:80)

at org.drools.core.phreak.RuleNetworkEvaluator.switchOnDoBetaNode(RuleNetworkEvaluator.java:569)

at org.drools.core.phreak.RuleNetworkEvaluator.evalBetaNode(RuleNetworkEvaluator.java:540)

at org.drools.core.phreak.RuleNetworkEvaluator.innerEval(RuleNetworkEvaluator.java:336)

at org.drools.core.phreak.RuleNetworkEvaluator.outerEval(RuleNetworkEvaluator.java:163)

at org.drools.core.phreak.RuleNetworkEvaluator.evaluateNetwork(RuleNetworkEvaluator.java:118)

at org.drools.core.phreak.RuleExecutor.reEvaluateNetwork(RuleExecutor.java:194)

at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:62)

at org.drools.core.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:974)

at org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1283)

at org.drools.core.impl.StatefulKnowledgeSessionImpl.internalFireAllRules(StatefulKnowledgeSessionImpl.java:1325)

at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1308)

at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1287)

at com.x.engine.drools.hardconstraints.MaxHoursPerDayTester.testMaxHoursTwoShiftsViolatedStartDateType(MaxHoursPerDayTester.java:244)

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

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

at java.lang.reflect.Method.invoke(Method.java:606)

at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)

at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)

at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)

at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)

at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)

at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)

at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)

at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)

at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)

at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)

at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)

at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)

at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)

at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)

at org.junit.runners.ParentRunner.run(ParentRunner.java:309)

at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)

at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)

Caused by: java.lang.ClassCastException: com.x.engine.domain.ShiftDate cannot be cast to com.x.engine.domain.dto.ProfileDayType

at com.x.engine.solver.rules.constraints.Rule_maxHoursPerDay1799802206AccumulateExpression0Invoker.evaluate(Rule_maxHoursPerDay1799802206AccumulateExpression0Invoker.java:17)

at org.drools.core.base.accumulators.JavaAccumulatorFunctionExecutor.accumulate(JavaAccumulatorFunctionExecutor.java:109)

at org.drools.core.rule.SingleAccumulate.accumulate(SingleAccumulate.java:82)

... 41 more

If I replace $shift.getShiftDurationMinutesByProfileType($type, $shiftDate) with $shift.getShiftDurationMinutesByProfileType($type, $shift.getShiftDate()) the issue goes away for some reason. Sadly this does not work as a workaround in my real case. 

Any ideas before I raise a JIRA issue?  

[Pavan Kumar J S]

I'm able to reproduce the same issue in version "6.3.0.Final".

The workaround that you have suggested works in my case.

Thanks

[murali mohan]

accumulate will work only on the elements of the fact it is collecting/matching. In your example, $shift : ShiftAssignment( ), is the fact that it is working on and it can only apply accumulate functions on the fields of ShiftAssignment. This explains why the workaround works.