Drools dynamic salience - drools

Question

global Integer rank1;
global Integer rank2;
rule "Data"
salience 10
when
req : Requests(status == "ON")
then
drools.getWorkingMemory().setGlobal("rank1", 8);
drools.getWorkingMemory().setGlobal("rank2", 6);
end
rule "1" extends "Data"
salience 8
when
req1 : Requests()
then
System.out.print("1");
end
rule "2" extends "Data"
salience 6
when
req2 : Requests()
then
System.out.print("2");
end
Here rank1 and rank2 are initialised as 0 in java code.
the output is 11112222.
i want the same output but instead of using static salience, i want it dynamic.
rule "1" extends "Data"
salience rank1
.......
but the code output is 21212121.

Answer 1

You need to set the globals before you insert the facts. Globals are not evaluated dynamically.
If you really need a more dynamic salience you should create a class
class Salience {
private int rank1;
private int rank2;
// ...
}
and insert a fact with appropriate values and change them as required. You'll then need the pattern added to the root rule:
rule "Data"
when
Salience( $rank1: rank1, $rank2: rank2 )
Requests(...)
then
and you can use $rank1 and $rank2 in salience attributes.
Note: Almost certainly there is a solution to your problem that can be expressed in logic and without salience, the usage which is almost always a design flaw.