Re: [rules-users] Object Referencing Error

In fact in your case you when condition doesn't make any sense - B will never equal the empty string as B isn't a string. You probable want the following: rule "foo" when $a :A(Type == "Prod" , objectB == null) then B bobject = new B(); bobject.setType("Prod"); bobject.setId($a.getNumber().getId()); modify($a) { setObjectB(bobject); }; end This rule only executes when objectB is null, this means you won't get into the loop as once you have created objectB the rule won't evaluate to true again. Thomas From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Esteban Aliverti Sent: 03 June 2010 23:43 To: Rules Users List Subject: Re: [rules-users] Object Referencing Error Yes, your rule entered in an infinite loop because when every time you insert/modify/retract a Fact, rules are reevaluated to check if the insertion/modification/retraction generates activations or not. In your case, your rule is being reevaluated every time you update your $a object, the evaluation ends firing the rule, and this starts an endless loop. If you only have this behavior with this rule, you can consider using the "no-loop" attribute. If your problem is multiple rules being re executed (and you don't wont that) you can use "lock-on-active" attribute. Try to read the documentation about these attributes for further information. It is very important for the people new in drools to understand the life cycle of a rule. Best, On Thu, Jun 3, 2010 at 7:33 PM, Fnu Mahalakshmi <FMahalakshmi@nyx.com<mailto:FMahalakshmi@nyx.com>> wrote: Hi, I tried what you said but program goes into an infinite loop. It does not break out of the when loop only. I did exactly as you mentioned. In the test information I put in a.type = "Prod" And a.bObject(new B()); Any idea whats wrong?? Thanks, M -----Original Message----- From: rules-users-bounces@lists.jboss.org<mailto:rules-users-bounces@lists.jboss.org> [mailto:rules-users-bounces@lists.jboss.org<mailto:rules-users-bounces@lists.jboss.org>] On Behalf Of rules-users-request@lists.jboss.org<mailto:rules-users-request@lists.jboss.org> Sent: Thursday, June 03, 2010 4:52 PM To: rules-users@lists.jboss.org<mailto:rules-users@lists.jboss.org> Subject: rules-users Digest, Vol 43, Issue 15 Send rules-users mailing list submissions to rules-users@lists.jboss.org<mailto:rules-users@lists.jboss.org> To subscribe or unsubscribe via the World Wide Web, visit https://lists.jboss.org/mailman/listinfo/rules-users or, via email, send a message with subject or body 'help' to rules-users-request@lists.jboss.org<mailto:rules-users-request@lists.jboss.org> You can reach the person managing the list at rules-users-owner@lists.jboss.org<mailto:rules-users-owner@lists.jboss.org> When replying, please edit your Subject line so it is more specific than "Re: Contents of rules-users digest..." Today's Topics: 1. Re: Object Referencing error: (Esteban Aliverti) ---------------------------------------------------------------------- Message: 1 Date: Thu, 3 Jun 2010 17:51:10 -0300 From: Esteban Aliverti <esteban.aliverti@gmail.com<mailto:esteban.aliverti@gmail.com>> Subject: Re: [rules-users] Object Referencing error: To: Rules Users List <rules-users@lists.jboss.org<mailto:rules-users@lists.jboss.org>> Message-ID: <AANLkTimeZIJ5VfMTBESLFJIWoc_4MEZSXbKMIXAvJRiC@mail.gmail.com<mailto:AANLkTimeZIJ5VfMTBESLFJIWoc_4MEZSXbKMIXAvJRiC@mail.gmail.com>> Content-Type: text/plain; charset="iso-8859-1" You can't modify bobject, becuase it doesn't exist inside the session. You just created it a few lines above. Maybe you need an insert() or maybe you need the bobject reference from the LHS. Something like this: *rule* "prod" *when* $a :A(Type == "Prod" , objectB != "") *then* B bobject = *new* B(); $a.getObjectB().setType( "Prod" ); $a.getObjectB().setId($a.getNumber().getId()); *update*($a); * end* Note that you need to update $a and not B, because A is the inserted Fact in your session. Best, 2010/6/3 Fnu Mahalakshmi <FMahalakshmi@nyx.com<mailto:FMahalakshmi@nyx.com>> -- XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Esteban Aliverti -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.jboss.org/pipermail/rules-users/attachments/20100603/f0f29dd... ------------------------------ _______________________________________________ rules-users mailing list rules-users@lists.jboss.org<mailto:rules-users@lists.jboss.org> https://lists.jboss.org/mailman/listinfo/rules-users End of rules-users Digest, Vol 43, Issue 15 ******************************************* Please consider the environment before printing this email. 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