RE: [rules-users] newbie question on "when" condition syntax

Hi Richard, The "when" section matches fact (object) patterns, so your requirement could be written as:- when there is a Test Fact 'A' and another Test Fact 'B' where "the 'x' property of 'A'" equals "the 'y' property of fact 'B' plus 1" then..... This would become:- rule "Rule 1" when Test( $y : y ) Test( x == ($y + 1) ) then System.out.println("Rule 1 matches"); end By default both patterns can match the same object, so test data:- A : x = 1, y = 1 B : x = 2, y = 1 Will cause the rule to activate twice:- A and B B and B With kind regards, Mike _____ From: rules-users-bounces(a)lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Richard Bremner Sent: 02 May 2008 08:53 To: rules-users(a)lists.jboss.org Subject: [rules-users] newbie question on "when" condition syntax Hi, say I have a class with two fields, x and y: public class Test { int x = 1; int y = 2; getters/setters... } I would like a rule which fires when y = x + 1 my initial thought would be something like: rule "Rule 1" when test : Test (y == x + 1) then System.out.println("Rule 1 matches."); end but this is invalid syntax and I can not find any examples of such a rule. I'm doing my best but reading the manual etc. I'm struggling with the syntax here and can't figure it out. any help really appreciated!