Hi, I couldn't find an solution to a problem I'm struggling with for many hours. Generally I'm trying to implement sequential mode rules. I have applied salience parameters to order the rules, but the engine is not executing these rules in that order. I use drools 5.0.1 in sequential mode, stateless session. As far as I understand the documentation, in this mode the rules should be fired in accordance to the salience attribute. RuleBaseConfiguration conf = new RuleBaseConfiguration(); conf.setSequential( true); KnowledgeBase knowledgeBase = KnowledgeBaseFactory.newKnowledgeBase( conf); session = knowledgeBase.newStatelessKnowledgeSession(); ... The following code snapshot proves that the execution order totally ignores salience - "rule2" is fired prior to the "rule1" causing NullPointerException since the Params is initiated in "rule1". package com.kaguar.pzu; import java.util.*; import com.kaguar.entities.*; global java.util.Set output; declare Params version : String modelGroup : Integer region : Integer end rule "rule1" salience 1000 when $c: Customer() then Params p = new Params(); p.setVersion( "1.0"); insert( p); output.add( p); $c.getPolicy().setParams( p); System.out.println( "Initiation complete"); end rule "rule2" salience 0 when exists Params() $c: Customer( vehicle.age == 2, policy.params.modelGroup == 1, policy.params.region == 1) then System.out.println( "test"); end Please help!!! -- View this message in context: http://n3.nabble.com/Sequential-mode-help-tp68511p68511.html Sent from the Drools - User mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

You might need to think about how the rules engine does it job. The first part is setting up the network to match your conditions, the second is then executing the consequences of those matched facts. What your seeing here is the first part finding nulls. So you need to make sure that all your facts are fully populated if they are being checked in the conditions, or you need to add conditions that check for null. I think salience does not come into play until after the facts have been matched.

> It seems I have misunderstood the documentation- the sequential mode > (https://hudson.jboss.org/hudson/job/drools/lastSuccessfulBuild/artifact/t...) > 3.3.7.1: > > "Order the Rules by salience and position in the ruleset (by setting a > sequence attribute on the rule terminal node)." > Sequential mode first evaluates all of the LHS. Which results in a single conflict set. It then evaluates the conflict set in salience and rule order. Modifying values will not result in the LHS being re-evaluated. Mark _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users