What is the relationship (extends/implements) between the classes/interfaces in your model - ContextFoodItem, FoodItem, ContextDiner, etc.. ? Could you also please specify the version of Drools you are using? Thanks! Davide
On 07/07/2014 03:04 PM, Borris wrote: > I am getting an unexpected cast exception. The backtrace looks like > > Exception in thread "main" java.lang.ClassCastException: > com.tastiereasier.rulez.ContextFoodItem cannot be cast to > com.tastiereasier.domain.FoodItem > at > ConditionEvaluatorb792d1e4169f4ac98945e49e1412d793.evaluate(Unknown Source) > at > org.drools.core.rule.constraint.MvelConstraint.evaluate(MvelConstraint.java:216) > at > org.drools.core.rule.constraint.MvelConstraint.isAllowedCachedLeft(MvelConstraint.java:185) > at > org.drools.core.common.SingleNonIndexSkipBetaConstraints.isAllowedCachedLeft(SingleNonIndexSkipBetaConstraints.java:141) > at > org.drools.core.phreak.PhreakJoinNode.doLeftInserts(PhreakJoinNode.java:98) > at org.drools.core.phreak.PhreakJoinNode.doNode(PhreakJoinNode.java:60) > at > org.drools.core.phreak.RuleNetworkEvaluator.switchOnDoBetaNode(RuleNetworkEvaluator.java:547) > at > org.drools.core.phreak.RuleNetworkEvaluator.evalBetaNode(RuleNetworkEvaluator.java:533) > at > org.drools.core.phreak.RuleNetworkEvaluator.innerEval(RuleNetworkEvaluator.java:334) > at > org.drools.core.phreak.RuleNetworkEvaluator.evalStackEntry(RuleNetworkEvaluator.java:224) > at > org.drools.core.phreak.RuleNetworkEvaluator.outerEval(RuleNetworkEvaluator.java:166) > at > org.drools.core.phreak.RuleNetworkEvaluator.evaluateNetwork(RuleNetworkEvaluator.java:116) > at > org.drools.core.phreak.RuleExecutor.reEvaluateNetwork(RuleExecutor.java:193) > at > org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:68) > at > org.drools.core.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:928) > at > org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1193) > at > org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1202) > at > org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1175) > at com.tastiereasier.rulez.Rulez.insertAndFire(Rulez.java:168) > at com.tastiereasier.rulez.Rulez.addDinerToContext(Rulez.java:310) > at com.tastiereasier.rulez.Rulez.<init>(Rulez.java:101) > at com.tastiereasier.rulez.Rulez.main(Rulez.java:44) > > The rules that are triggering this are: > > rule contextDinerDislike > enabled true > when > ContextDiner( $diner; ) > DatumPreference > ( > datumPreferenceType == DatumPreference.Type.PREFERENCE, > belief.factor < 0.0, > $datum: datum > ) > from $diner.getDatumPreferences() > then > insert( new ContextFoodItem( (FoodItem) $datum, true ) ); > end > > rule spotNewContextDinerLike > enabled true > when > ContextDiner( $diner; ) > DatumPreference > ( > datumPreferenceType == DatumPreference.Type.PREFERENCE, > belief.factor > 0.0, > $datum: datum > ) > from $diner.getDatumPreferences() > then > insert( new ContextFoodItem( (FoodItem) $datum, false ) ); > end > > If I disable either rule, then the other proceeds fine and no cast > exception happens. > > I can't see why the cast should ever be asked for - it doesn't make sense. > > If I changed the boolean parameter in the new in the insert - so both > are either true or both > are either false, there are no cast exceptions (there must be a clue here). > > If I put a debug after the insertion, the backtrace actually happens > after return from the > insert() method - implying it's something on the agenda? > > I tried using the Audit stuff to see if it gave any clues - but I've > never used that before > and simply got a heap exhaustion from Eclipse after 1/2 hour trying to > ingest something like 200 > meg of trace data - I've got a lot of data being initialised into the > workspace before these rules > get a chance to do anything. > > It's feeling remarkably like a bug to me, but I don't know how to > interpret the backtrace usefully, > so it's possible I've got something messed up elsewhere - although I've > disabled massive amounts > of rules that I can. > > I grabbed a snapshot last night and it didn't change anything. (I was on > a snapshot from early June to fix being able to have Drools editor > reference my external jars.) > > Does this look like a bug or user error? It's going to take some effort > to try and extract a test case > so I really don't want to spend the effort on that unless it looks the > only way. > > Sage observations most appreciated. > > Borris > > > > _______________________________________________ > rules-users mailing list > rules-users@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > _______________________________________________ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users
