[rules-users] Drools Debugging

[Swindells, Thomas]

Use salience or some other order to control the facts. But I think the key point to remember is that Drools isn't stable, given the same set of rules and the same set of input in the same order there is no guarantee that the rules will execute in the same order unless there is something in the rules which forces them to do so. 99.9% of the time the version you run will produce the same ordered output but perhaps 0.1% of the time it could occur in a different order.

This can lead to some nasty intermittent bugs if rules aren't written correctly and make implicit assumptions about the order they run.

My suspicion is this is due to some hash map/set buried deep in the code somewhere controlling the order of equal priority activations, but I've never managed to work out where this is (if my theory is even correct). It would be nice if it were changed to a version that produces a consistent ordering every time (given the exact same set of inputs).

Thomas

> -----Original Message-----
> From: rules-users-bounces at lists.jboss.org [mailto:rules-users-
> bounces at lists.jboss.org] On Behalf Of Veera
> Sent: 09 February 2012 06:25
> To: rules-users at lists.jboss.org
> Subject: [rules-users] Drools Debugging
>
> Hi All,
>
> I have one doubt that is : When i compiling a sample HelloWorld Drools
> program it is printing output like :
> Hello World
> Goodbye cruel world
>
> and i added a simple rule like :
>  rule "test"
>     when
>         eval(true)
>     then
>         System.out.println( "Hello!!!" ); end
>
> When i compile the output is :
> Hello!!!
> Hello World
> Goodbye cruel world
>
> But when i debug it is showing output like:
> Hello World
> Goodbye cruel world
> Hello!!!
>
> Can anybody help me how to get the same output when i debug also...
>
> Regards,
> Veera
>
>
> --
> View this message in context: http://drools.46999.n3.nabble.com/Drools-
> Debugging-tp3728574p3728574.html
> Sent from the Drools: User forum mailing list archive at Nabble.com.
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users


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