Re: [rules-users] Initialize Global

It's normal. Globally, the rule engine works in two steps : - first : the activation (the "when" statement) - second : the execution (the "then" statement) with salience, ruleflow ... In your test, you have in the first step objectList = null and in the second step objectList = [1, 2]. If you want to re-activate your rule, you have to do an update/insert/remove action... But you can't do that with globals. So you need to use the WM facts. Waruzjan Shahbazian-2 wrote: > I have the same "problem", but eval(objectList == null) doesn't work. If > I don't execute "drools.getWorkingMemory().setGlobal()" it "works fine", > as if the rule activates and the object is null. > > global List objectList; > > rule "Start" > salience 101 > when > #conditions > then > objectList = new ArrayList() ; > objectList.add("1"); > objectList.add("2"); > System.out.println("Start objectList:"+objectList); > //drools.getWorkingMemory().setGlobal("objectList", objectList); > end > > rule "end" > salience 97 > when > eval (objectList == null) > then > System.out.println("End objectList: "+objectList); > end > > gives: > > Start objectList:[1, 2] > End objectList: null > > Next I uncomment the "drools.getWorkingMemory().setGlobal("objectList", > objectList);" and run the rule again an get: > > Start objectList:[1, 2] > End objectList: [1, 2] > > so the objectList isn't null, but the rule still activates... > > Kris Verlaenen schreef: > >>> That initialized my global but the rule still runs every execution. >>> Can I >>> disable the rule after the first execution? >>> >> What do you mean by "every execution". A rule should only be executed >> once, unless it gets reactivated (which should not be the case in this >> situation). >> >> >>> I would like to use (if (objectList==null)). My list is not >>> immutable. Can >>> I make a similar rule for the LHS? >>> >> You can test whether the global is null using eval( objectList == null >> ) in the LHS of the rule. >> >> Kris >> _______________________________________________ >> 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 > > >