Re: [rules-users] Exception executing consequence for rule xxx in yyy: java.lang.RuntimeException: unable to access field

A rule to repro this situation: The rule: ... rule "Assignment In Action Test" when obj : Foo() then obj.x = 1; System.out.println("Rule Fired!"); end ... Definition of class Foo: public class Foo { public int x; public int getX() { return x; } public void setX(int x) { this.x = x; } } Objects been inserted: Foo foo1 = new Foo(); foo1.x = 0; Foo foo2 = new Foo(); Foo2.x = 1000; Note that if only one Foo object is inserted, things work fine. If more than one Foo objects are inserted, we see this Exception: Exception executing consequence for rule "Assignment In Action Test" in com.sample: java.lang.RuntimeException: unable to access field at org.drools.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39) at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1283) at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1209) at org.drools.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1442) at org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:710) at org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:674) at org.drools.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:230) at com.sample.AssignmentInActionTestMain.main(AssignmentInActionTestMain.java:37) Caused by: java.lang.RuntimeException: unable to access field at org.mvel2.optimizers.impl.refl.nodes.DynamicFieldAccessor.setValue(DynamicFieldAccessor.java:66) at org.mvel2.optimizers.impl.refl.nodes.IndexedVariableAccessor.setValue(IndexedVariableAccessor.java:43) at org.mvel2.compiler.CompiledAccExpression.setValue(CompiledAccExpression.java:59) at org.mvel2.ast.DeepAssignmentNode.getReducedValueAccelerated(DeepAssignmentNode.java:92) at org.mvel2.MVELRuntime.execute(MVELRuntime.java:85) at org.mvel2.compiler.CompiledExpression.getValue(CompiledExpression.java:126) at org.mvel2.MVEL.executeExpression(MVEL.java:930) at org.drools.base.mvel.MVELConsequence.evaluate(MVELConsequence.java:101) at org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1273) ... 6 more Caused by: java.lang.NullPointerException at org.mvel2.DataConversion.convert(DataConversion.java:118) at org.mvel2.optimizers.impl.refl.nodes.DynamicFieldAccessor.setValue(DynamicFieldAccessor.java:61) ... 14 more -----Original Message----- From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Wolfgang Laun Sent: Wednesday, January 16, 2013 10:35 AM To: Rules Users List Subject: Re: [rules-users] Exception executing consequence for rule xxx in yyy: java.lang.RuntimeException: unable to access field What's the type of $billingOutputRuleContext.retroPreviousBillAmount? On 16/01/2013, magaram <magaram(a)deltadentalmi.com&gt; wrote: _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users ********************************************************************** CONFIDENTIALITY NOTICE: The information contained in this email is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. If you are not the intended recipient, you are hereby notified that any unauthorized review, use, dissemination, distribution or copying of this communication is prohibited and may be subject to legal restriction or sanction. If you have received this email in error, please notify the sender immediately to arrange for return or destruction of the information and all copies. If you are the intended recipient but do not wish to receive communications through this medium, please advise the sender immediately. Thank you