[rules-users] "Exists" CE behaviour

[Chivotario Martin]

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 at in.ibm.com>

> 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 at gmail
>             .com>                                                      To
>             Sent by:                  rules-users at lists.jboss.org
>             rules-users-bounc                                          cc
>             es at lists.jboss.or
>             g                                                     Subject
>                                       [rules-users] "Exists" CE behaviour
>
>             13/07/2009 14:11
>
>
>             Please respond to
>             Rules Users List
>             <rules-users at 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 at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
>
>
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20090713/e48523fb/attachment.html