[rules-users] Re: how to use Array type in Drools

Hi, I am using Drools 4.0.7 GA. I want to use Array type in my rule condition. My drl is like below: > package org.drools.examples.test; > > import org.drools.examples.HelloWorldExample.Message; > > rule "check.array" > dialect "java" > when > m:Message( arr[0] == "1" ) > then > System.out.println( "===check array ok===" ); > end arr is an int type array. When I run the test case, I meet below exception: > Exception in thread "main" org.drools.RuntimeDroolsException: Exception > executing predicate eval( arr[0] == "1" ) > at > org.drools.rule.PredicateConstraint.isAllowed(PredicateConstraint.java:216) > at org.drools.reteoo.AlphaNode.assertObject(AlphaNode.java:137) > at > org.drools.reteoo.SingleObjectSinkAdapter.propagateAssertObject(SingleObjectSinkAdapter.java:22) > at > org.drools.reteoo.ObjectTypeNode.assertObject(ObjectTypeNode.java:162) > at org.drools.reteoo.Rete.assertObject(Rete.java:175) > at > org.drools.reteoo.ReteooRuleBase.assertObject(ReteooRuleBase.java:192) > at > org.drools.reteoo.ReteooWorkingMemory.doInsert(ReteooWorkingMemory.java:71) > at > org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:911) > at > org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:883) > at > org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:684) > at > org.drools.examples.HelloWorldExample.main(HelloWorldExample.java:69) > Caused by: org.mvel.CompileException: illegal use of []: unknown type: [I > at > org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.getCollectionProperty(ReflectiveAccessorOptimizer.java:482) > at > org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:274) > at > org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.optimizeAccessor(ReflectiveAccessorOptimizer.java:110) > at org.mvel.ASTNode.getReducedValueAccelerated(ASTNode.java:186) > at > org.mvel.ast.BinaryOperation.getReducedValueAccelerated(BinaryOperation.java:21) > at org.mvel.MVELRuntime.execute(MVELRuntime.java:90) > at org.mvel.CompiledExpression.getValue(CompiledExpression.java:111) > at org.mvel.MVEL.executeExpression(MVEL.java:234) > at > org.drools.base.mvel.MVELPredicateExpression.evaluate(MVELPredicateExpression.java:45) > at > org.drools.rule.PredicateConstraint.isAllowed(PredicateConstraint.java:209) > ... 10 more > Can anyone kindly tell me how to use Array type in Drools? Thanks in advance! - Zeke