Brainteaser Drools: Testing Objects

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This can be a hard one, since it requires from you to be familiar with Drools.

Consider the condition side of the following rules:

rule "object comparison one"
no-loop

when
	$customer1 : Customer( )
	$customer2 : Customer(this != $customer1)
then
	System.out.println("Rule one - Objects are equal");
end

rule "object comparison two"
no-loop

when
	$customer1 : Customer( )
	$customer2 : Customer(eval(this != $customer1))
then
	System.out.println("Rule two - Objects are equal");
end

Question(s):
Which of the two rules does valid comparison of the two Customer instances?
Which of the two rules is invalid? Why?

Looking forward for your answers dear readers

Resources:
Drools JBoss Rules 5.0 Developer’s Guide July 2009

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Comments
  • Alexander Zagniotov August 23, 2009 at 11:03 am

    Brainteaser Drools: Testing Objects:
    This can be a hard one, since it requires from you to be familiar with Dr.. http://bit.ly/4wykv0

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