Rule Engines

Evening All

I am interested in adding a Rule Engine to a product I am developing at
the moment.

I understand the principles of how they work, forward/backward chaining
etc, what I am undure about is how they added to an application.

I have had a look at JRules (Drools) and that seemed to be a case of
passing the object to the rule engine there by giving it access to the
variable in the object.

Although this would seem logical and fairly simple I'm left thinking
that what I'm looking at is needing to provide many object to provide
all the data for the business rules.

What I don't seem to be able to find is a clean simple introduction to
rule engines and how they are used to confirm my understanding and
discover if my beliefs are correct?

Any suggestions?

Tom

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