A bit more information I just gathered:

rule "Set Parameter Value"

when

            ParameterUpdateEvent($name : name, $newParamValue : value)

from entry-point "ParamUpdateStream"

            $param : Parameter(name == $name)

then

            $param.setValue($newParamValue);

            System.out.println("New value = " + $param.getValue());

end

Only fires once for each stream insert I do, so it seems to have something to do with either the window or accumulate in the rule below.

Any help is greatly appreciated.

Thanks

 Glenn

From: rules-users-bounces@lists.jboss.org [mailto:rules-users-bounces@lists.jboss.org] On Behalf Of Glenn Macgregor
Sent: 16 February 2010 16:44
To: Rules Users List
Subject: [rules-users] Event Streams

Hi All…again,

I am slowly working through my testcase and it seems to be going OK so far. My question is about stored events, @expires set to 1d for instance, and processing rules.

declare ParameterUpdateEvent

      @role(event)

      @expires(1d1h)

End

rule "Print Average"

no-loop true

when

            ParameterUpdateEvent($paramName : name, $newParamValue : value)

from entry-point "ParamUpdateStream"

            $param : Parameter(name == $paramName)

            $averageUpdateValue : Number(doubleValue >= 1) from accumulate(

                  ParameterUpdateEvent(name == $paramName, $value : value)

                  over window:time(15m)

from entry-point "ParamUpdateStream", average($value))

#Number($averageUpdateValue : doubleValue)

then

#System.out.println("Here");

            System.out.println("Average update value for " + $paramName +

" = " + $averageUpdateValue);

end

Inside my unit test I add a single event to the stream and this rule fires and prints the average value…which is the value of the last update because it is the first event is has seen. I send in another event with a different value and this rule fires twice and prints the correct value both times. From what I can gather this is due to the fact that there are 2 events on the stream at this point even though I have processed one already.

What is the best practice to handling only the last event on a stream? Since the documentation states that events should be immutable I can’t add a processed flag.

Thank you for all your support thus far.

 Glenn