Thanks for replies. Actually what I did now is I declared my fact into drl file and then I'd added an @expires to it. It works fine but now the problem is that for every fact inserted I'd also inserted an event for it. 

Now as the drl file can be updated by user so say he'd defined expiry time for events as 1m and for facts as 10s in this case since I'm using sliding window for events and based on this event I'm fetching the fact. So now I'll be getting the event but facts will not be available as the 2nd fact came after 20s hence the rule will not be fired. below is the sample rule.

declare MyEvent
	@role(event)
	@expires( 1m )
end

declare MyFact
	@expires( 10s )
end
rule "MyCorrelation"
	no-loop true
	dialect "mvel"
	lock-on-active
	when
		$E1 : MyEvent( prop1 == 2, $entityA : entity ) over window:time(60s) from entry-point NotificationStream
		$E2 : MyEvent( this != $E1, prop1 == 1, $entityB : entity ) over window:time(60s) from entry-point NotificationStream
		$F2 : MyFact(this.entity == $entityB)
		$F1 : MyFact(this.entity == $entityA)
	then
		System.out.println("I'm executed successfully");
end

Now what I want is that I can define the @expires time at a single location or I can verify the logic of these rules?

Also if say I'd defined the @expires for event as 10s while in sliding window I'm using over:time(1m) then also it is not same.
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