[rules-users] Initialize Global

[Waruzjan Shahbazian]

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 at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users