Hi.

 

I've currently evaluating Drools 4.0 for a project of ours and I'm running into some problems.

 

I have a rule which looks like this:

 

rule "W250.42 Editable"

      when

            DTO(w250_4_1.value in ("0" ,"1" ,"6" ,"7" ,"A" ,"C" ,"D" ,"G" ,"L" ,"M" ,"P" ,"Q" ,"S" ,"V" ,"Z" ) )

      then

            System.out.println ("0" );

            Action action = createAction("W250.42" , false , true );

            retList.add(action);

end

 

 

both DTO and w250_4_1 are extremely simple beans. w250_4_1 just has 1 property 'value' which is a String and DTO has one property w250_4_1 which is the bean w250_4_1 ..

 

Now when I put "0" into w250_4_1 then everything works fine. The rule is true and the 'then' portion is executed. However, if I set w250_4_1 to "6" (which is also present in the in (…)) then I get the following error.

 

org.drools.RuntimeDroolsException : Exception executing predicate org.drools.base.mvel.MVELPredicateExpression@118fa47

      at org.drools.rule.PredicateConstraint.isAllowed(PredicateConstraint.java:197 )

      at org.drools.reteoo.AlphaNode.assertObject(AlphaNode.java:122 )

      at org.drools.reteoo.CompositeObjectSinkAdapter.propagateAssertObject(CompositeObjectSinkAdapter.java:317 )

      at org.drools.reteoo.ObjectTypeNode.assertObject(ObjectTypeNode.java:168 )

      at org.drools.reteoo.Rete.assertObject(Rete.java:168 )

      at org.drools.reteoo.ReteooRuleBase.assertObject( ReteooRuleBase.java:190)

      at org.drools.reteoo.ReteooWorkingMemory.doInsert(ReteooWorkingMemory.java:70 )

      at org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:848 )

      at org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:822 )

      at org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:623 )

      at com.sample.DroolsTest.main( DroolsTest.java:34)

Caused by: org.mvel.PropertyAccessException: failed to access property: <<==>> in: class com.sample.DTOShadowProxy

      at org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:137 )

      at org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.optimizeAccessor(ReflectiveAccessorOptimizer.java:96 )

      at org.mvel.ASTNode.getReducedValueAccelerated(ASTNode.java:194 )

      at org.mvel.ast.Or.getReducedValueAccelerated(Or.java:18 )

      at org.mvel.MVELRuntime.execute( MVELRuntime.java:87)

      at org.mvel.CompiledExpression.getValue( CompiledExpression.java:98)

      at org.mvel.MVEL.executeExpression( MVEL.java:202)

      at org.drools.base.mvel.MVELPredicateExpression.evaluate(MVELPredicateExpression.java:36 )

      at org.drools.rule.PredicateConstraint.isAllowed(PredicateConstraint.java:191 )

      ... 10 more

Caused by: org.mvel.PropertyAccessException: could not access property ('=')

      at org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.getBeanProperty(ReflectiveAccessorOptimizer.java:252 )

      at org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:106 )

      ... 18 more

 

If I keep w250_4_1 as "0", but move "0" in the rule to any other place place in the in() list (e.g. in ("1","0",…), then I get a similar error.

 

I get similar errors when trying to use 'not in' in the same circumstance, except that then the property is ('!')

 

What seems to be the issue?

 

Thanks in advance!

 

Regards,

 

--Arsalan