Re: [rules-users] "Exists" CE behaviour

Hi Wolfgang, I do not know if i can use the issue tracker to post this as an issue, as i don't know if i'm allowed to do so, and also if this is officially, really a bug or the expected behaviour :) . However i left a complete piece of code showing the behaviour i'm getting : RuleTester.java package org.drools.test; import org.drools.KnowledgeBase; import org.drools.KnowledgeBaseConfiguration; import org.drools.KnowledgeBaseFactory; import org.drools.RuleBaseConfiguration; import org.drools.builder.KnowledgeBuilder; import org.drools.builder.KnowledgeBuilderFactory; import org.drools.builder.ResourceType; import org.drools.io.ResourceFactory; import org.drools.runtime.StatefulKnowledgeSession; public class RuleTester { private static final int MAX_EVENTS = 5; public class Foo { } public void test() { KnowledgeBaseConfiguration config = KnowledgeBaseFactory.newKnowledgeBaseConfiguration(); ((RuleBaseConfiguration)config).setRuleBaseUpdateHandler( null ); KnowledgeBase kbase = KnowledgeBaseFactory.newKnowledgeBase(config); StatefulKnowledgeSession session = kbase.newStatefulKnowledgeSession(); for (int i=0; i<MAX_EVENTS; i++) { session.insert(new Foo()); } for (int i=1; i<3; i++) { KnowledgeBuilder kbuilder = KnowledgeBuilderFactory.newKnowledgeBuilder(); kbuilder.add( ResourceFactory.newClassPathResource( "test"+i+".drl" ), ResourceType.DRL); if( kbuilder.hasErrors() ) { System.out.println( kbuilder.getErrors() ); return; } kbase.addKnowledgePackages( kbuilder.getKnowledgePackages() ); int fireCount = session.fireAllRules(); System.out.println("Test"+i+".drl , number of rules fired = "+fireCount); } session.dispose(); } public static void main(String[] args) { RuleTester tester = new RuleTester(); tester.test(); } } test1.drl import org.drools.test.RuleTester.Foo; rule "notNotRule" when exists ( Foo() ); then System.out.println("Rule fired..."); end test2.drl import org.drools.test.RuleTester.Foo; rule "notNotRule" when not ( not ( Foo() ) ); then System.out.println("Rule fired..."); end Using Drools 5.0.1-Final , the expected output would be : > Test1.drl , number of rules fired = 0 > Rule fired... > Test2.drl , number of rules fired = 1 If someone allows me to open this a a JIRA i would try to understand how to use it :D and would do so. Regards, Manuel. 2009/7/13 Wolfgang Laun <wolfgang.laun(a)gmail.com&gt; > Quite right, since not(not(Foo())) is equivalent to exists(Foo()). > > Martin, would you please submit a JIRA? > > -W > > > > > > On 7/13/09, Chivotario Martin <chivotario(a)gmail.com&gt; wrote: > > Hi Visu, > > > > My understanding (also tested) is that activations are created no matter the > > knowledge base has the rule packages loaded > > before or after the working memory is filled with facts, but the execution > > of the rules happens automatically if the working memory is filled in > > advance.Setting the RuleBaseUpdateHandler to null, prevents the execution of > > the rules but keeps activations to be created when adding a rule to the > > kbase. > > In this case, it seems the exists CE only creates activations if the rules > > are loaded before the working memory is populated. > > But this doesn't happen if i change the statement : > > > > exists ( Foo() ) --> not ( not ( Foo() ) ) > > > > In this case, activations are created no matter whether the kbase is empty > > or not before populating the WM. > > > > > > > > > > 2009/7/13 Viswanathan Nageswaran <visu.nageswaran(a)in.ibm.com&gt; > > > > > Chivotario, > > > > > > >From what I understand, the activation of rules happen as facts are > > > inserted into the working memory; hence it is important for the session to > > > be begun against a knowledge base that has the rule packages loaded before > > > the facts are inserted. > > > > > > -Visu > > > > > > > > > > > > > > > Chivotario Martin > > > <chivotario@gmail > > > .com> To > > > Sent by: rules-users(a)lists.jboss.org > > > rules-users-bounc cc > > > es(a)lists.jboss.or > > > g Subject > > > [rules-users] "Exists" CE behaviour > > > > > > 13/07/2009 14:11 > > > > > > > > > Please respond to > > > Rules Users List > > > <rules-users@list > > > s.jboss.org> > > > > > > > > > > > > > > > > > > > > > > > > Hi , > > > > > > I'm trying to use the Exists keyword within my rules with the following > > > snippet : > > > > > > // Create a session > > > KnowledgeBaseConfiguration config = > > > > > KnowledgeBaseFactory.newKnowledgeBaseConfiguration(); > > > > > ((RuleBaseConfiguration)config).setRuleBaseUpdateHandler( > > null ); * > > > KnowledgeBase kbase = > > KnowledgeBaseFactory.newKnowledgeBase(config); > > > StatefulKnowledgeSession session = > > kbase.newStatefulKnowledgeSession(); > > > > > > // Add some objects > > > for (int i=0; i<5; i++) { > > > } > > > > > > > > > // Add a DRL to the kbase > > > KnowledgeBuilder kbuilder = > > KnowledgeBuilderFactory.newKnowledgeBuilder(); > > > kbuilder.add( ResourceFactory.newClassPathResource( > > "test/existsTest.drl" > > > ), ResourceType.DRL); > > > kbase.addKnowledgePackages( > > kbuilder.getKnowledgePackages() ); > > > > > > // Fire rules > > > int fireCount = session.fireAllRules(); > > > > > > > > > existsTest.drl : > > > > > > rule "existsTest" > > > ( Foo() ) ); (2) > > > > > > end > > > > > > When launched , the rule is not fired (no messages , fireCount 0), but it > > > is when changing > > > exists with a double not condition (2). > > > If the working memory is populated after adding the rules file, the exists > > > CE works as expected. > > > * I've used no RuleBaseUpdateHandler preventing automatic activations to > > be > > > executed so fireAllRules can be used to get the fireCount, but commenting > > > this line out doesn't change the results. > > > > > > Probably i'm doing something wrong so a little help would be very > > > appreciated. > > > > > > Regards, > > > Manuel. > > > _______________________________________________ > > > 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 > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users