Greetings.
I am trying to find the correct approach to defining and using Java5 Enum's in Drools constraints.

Psudo code:
Class RuleRequest {
      ... other attributes ...
      // RequestType is an enum type.
      RequestType type ;

      public RequestType getRequestType() {
           return type;
      }
}

public enum RequestType {
   INTERNAL("internal"), EXTERNAL("external");
}

Drools Rule:
# 1st Constraint - I could have listed the type in the constraint for RuleRequest but say I want that to be in a separate constraint
# 2nd Constraint - on the nested RequestType enum
req: RuleRequest(..some match not based on the RequestType but other attributes of RuleRequest...)
type: RequestType( ??? == RequestType.INTERNAL ) from req.requestType

What should be plugged in ??? to be able to match the requestType.  Interestingly, if I say
type: RequestType( this == RequestType.INTERNAL ) from req.requestType  when the ruleRequest has an RequestType of INTERNAL, the matching works.  But I do not see any examples/reference in the Drools documentation on the usage of "this" in constraints. I saw a posting from Edson T. using this which is why I tried it in the first place.

Question
- What is the expectation for the Enum.  Should it have methods (getters) that return the Enum type itself or methods that return the strigified value of the Enum?
- What is syntax and usage practices for the usage of the "this" keyword
- What really happens when the Drools engine does the == comparison on Enum's.  Does it convert to the string value of the enum and then compare that or is there something else in play. 

I hope I have asked valid questions as I see many questions relating to Enum but maybe a definitive/suggested approach and explanation from the drools dream team may serve as a good reference on this subject.

Thanks.
- Krishna






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