Re: [rules-users] Getting facts from external source using 'from' and parametrized method call

And did the stack trace change? Can you post more details (drl, java src)? Przemysław Różycki wrote: > Yes, I did. This was the first thing I've checked. > > Best regards, > Przemek > > Jaroslaw Kijanowski pisze: >> Did you set the global on your session? >> >> http://downloads.jboss.com/drools/docs/4.0.7.19894.GA/html_single/index.h... >> >> >> Cheers >> >> Przemysław Różycki wrote: >>> Sorry for responsing myself, but I'm still working on it and found >>> that when factSource is a fact, not global, the rule works very >>> well. I mean, this rule works fine: >>> >>> rule "My Rule" >>> when >>> $factSrc : FactSource( ) >>> $fact : Fact( ) from $factSrc.getSomeFacts("a","b","c") >>> then >>> // do something >>> end >>> >>> so what's the difference between invocation on global object and >>> invocation on fact object? Why the first one doesn't work and the >>> second one works? >>> >>> Best regards, >>> Przemek >>> >>> >>> Przemysław Różycki pisze: >>>> Hi, >>>> >>>> could I ask for some advice, please, how to use a parametrized >>>> method call to get some data using 'from' element in LHS. >>>> >>>> To be more precise, I would like to do something like this: >>>> >>>> rule "My Rule" >>>> when >>>> $fact : Fact( ) from factSource.getSomeFacts("a","b","c") >>>> then >>>> // do something >>>> end >>>> >>>> where factSource is for example some global and >>>> getSomeFacts(String,String,String) is a parametrized method that >>>> returns some array of Fact objects. >>>> >>>> Unfortunately, when I try to launch the following rule I have an >>>> error: >>>> >>>> Exception in thread "main" org.mvel.PropertyAccessException: unable >>>> to resolve property: factSource.getSomeFacts("a","b","c") >>>> at >>>> org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:295) >>>> >>>> at >>>> org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.optimizeAccessor(ReflectiveAccessorOptimizer.java:110) >>>> >>>> at >>>> org.mvel.ast.VariableDeepPropertyNode.getReducedValueAccelerated(VariableDeepPropertyNode.java:26) >>>> >>>> at >>>> org.mvel.ast.PropertyASTNode.initializePropertyNode(PropertyASTNode.java:70) >>>> >>>> at >>>> org.mvel.ast.PropertyASTNode.getReducedValueAccelerated(PropertyASTNode.java:24) >>>> >>>> at org.mvel.MVELRuntime.execute(MVELRuntime.java:90) >>>> at >>>> org.mvel.CompiledExpression.getValue(CompiledExpression.java:111) >>>> at org.mvel.MVEL.executeExpression(MVEL.java:252) >>>> at >>>> org.drools.base.dataproviders.MVELDataProvider.getResults(MVELDataProvider.java:55) >>>> >>>> at org.drools.reteoo.FromNode.assertTuple(FromNode.java:68) >>>> at >>>> org.drools.reteoo.SingleTupleSinkAdapter.createAndPropagateAssertTuple(SingleTupleSinkAdapter.java:55) >>>> >>>> at >>>> org.drools.reteoo.LeftInputAdapterNode.assertObject(LeftInputAdapterNode.java:116) >>>> >>>> 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$WorkingMemoryReteAssertAction.execute(ReteooWorkingMemory.java:181) >>>> >>>> at >>>> org.drools.common.AbstractWorkingMemory.executeQueuedActions(AbstractWorkingMemory.java:1312) >>>> >>>> at >>>> org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:915) >>>> >>>> at >>>> org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:883) >>>> >>>> at >>>> org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:684) >>>> >>>> at com.sample.DroolsTest6.main(DroolsTest6.java:29) >>>> Caused by: java.lang.NullPointerException >>>> at >>>> org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.getMethod(ReflectiveAccessorOptimizer.java:530) >>>> >>>> at >>>> org.mvel.optimizers.impl.refl.ReflectiveAccessorOptimizer.compileGetChain(ReflectiveAccessorOptimizer.java:261) >>>> >>>> ... 21 more >>>> >>>> Documentation says: >>>> >>>> "The from Conditional Element allows users to specify a source for >>>> patterns to reason over. This allows the engine to reason over data >>>> not in the Working Memory. This could be a sub-field on a bound >>>> variable or the results of a method call." >>>> >>>> so I assume that it is possible to do what I want. If not, could I >>>> ask for an advice of some workaround, please? >>>> >>>> Best regards, >>> >>> _______________________________________________ >>> rules-users mailing list >>> rules-users(a)lists.jboss.org >>> https://lists.jboss.org/mailman/listinfo/rules-users >>> >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users > > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users