Why's my rule not working properly? I'm pointing my engineer and workorder filling with my list of skills, even so, it is not correctly giving the workorder to engineer.

There is an available engineer with a skill
and there is an unassigned workorder with skill
and workorder skill is equals to engineer skill
then assign workorder to engineer

rule "requiredSkill"
when
$engineer : Engineer()
SkillEngineer( $skill : skill, engineer == $engineer ) from $engineer.skillEngineerList
$workOrder : WorkOrder( engineer == $engineer )
$workOrderRequiredSkill : SkillWorkOrder( skill == $skill, workOrder == $workOrder ) from $workOrder.requiredSkills 
then
insertLogical(new IntConstraintOccurrence("requiredSkill", ConstraintType.NEGATIVE_HARD,
1, $engineer));
end

it always set the same engineer to every workorder


2013/2/18 André Fróes <arfmoraes@gmail.com>
I found (i guess) a way to iterate over list, but it is not comparing and assigning the workorder now. I tried this way:
-----------------
rule "requiredSkill"
   when
       There is an unassigned workorder
       and the workorder has a requiredSkill other than null

       and there is an engineer
       and the engineer has a skill other than null

       and engineer skill is the same as workorder skill
   then
       assign workorder to engineer
engineer
-----------------
this is how i tried implementing;
-----------------
rule "requiredSkill"
when
$workOrder : WorkOrder() 
   $woReqSkill : SkillWorkOrder($requiredSkillWO : skill , eval(skill != null)) from $workOrder.requiredSkills 
   
   $engineer : Engineer()
   $engineerSkill : SkillEngineer($engSkill : skill, eval(skill != null)) from $engineer.skillEngineerList
   
   exists SkillEngineer( $engineerSkill.skill == $woReqSkill.skill )
then
insertLogical(new IntConstraintOccurrence("requiredSkill", ConstraintType.NEGATIVE_HARD,
1, $engineer));
end
-----------------
But all workorders are going to the same one, it is not validating if one is equals to other.


2013/2/18 André Fróes <arfmoraes@gmail.com>
Hello everyone!

How can I compare 2 lists with a rule?
I upgraded my basic model to a more complex one now, but now I hit a wall. My WorkOrder have a List of skills, and my Engineer also have a list of Skills and I have to compare one with another.

Example:

Engineer A have skill ABC 1
Engineer B have skill ABC 2
Engineer C have skill ABC 3

WorkOrder A needs an engineer with skill ABC 3
WorkOrder B needs an engineer with skill ABC 1
WorkOrder C needs an engineer with skill ABC 2

The result should be this:

Engineer A will receive WorkOrder B
Engineer B will receive WorkOrder C
Engineer C will receive WorkOrder A
---------------

I am able to sort it by time, but not by skill, and I don't know how to loop over each list to find if one have the skills needed to fulful the other. These are my classes involved:

WorkOrder attributes:
--------
private int requiredWorktime;
private Priority priority;(enum)
private Severity severity;(enum)
private List<SkillWorkOrder> requiredSkills;
--------
Engineer attributes:
--------
private int worktime;
private String name;
private List<SkillEngineer> skillEngineerList;
--------
Skill attributes:
--------
private String name;
--------

both SkillEngineer and SkillWorkOrder are classes that simple receives the named class and a Skill:
Eg:
private Engineer engineer; //Or WorkOrder
private Skill skill;

Is it possible to iterate over these 2 lists, by drool rule, to check wich engineer have most coincidences with an workorder? (Eg: if and Engineer have skill ABC1, ABC2 and a WorkOrder needs an engineer with skill ABC1, ABC2 and ABC3 he would be choseng among the others because his skills)