[rules-users] Trying to get Sliding Windows to work
Edson Tirelli
tirelli at post.com
Thu Apr 2 07:52:07 EDT 2009
Need to fix the error message, but it seems you are trying to use the
sliding window on regular facts... sliding window only makes sense for
events...
Also, the property you are using to set the event processing mode seems
wrong. Check here:
https://hudson.jboss.org/hudson/job/drools/lastSuccessfulBuild/artifact/trunk/target/docs/drools-fusion/html/ch02.html#d0e1067
[]s
Edson
2009/4/2 nestabur <nestabur at gmail.com>
>
>
> Hi All,
>
> I'm trying to use sliding windows with guvnor, I deploy the package in my
> rule engine as:
>
> Properties props = new Properties();
> props.put("url", rulePackagePath);
> props.put("eventProcessingMode", "stream");
>
> agent = RuleAgent.newRuleAgent(props);
> session = agent.getRuleBase().newStatefulSession();
>
> When I insert a fact into the working memory as:
> session.insert(fact);
> session.fireAllRules();
>
> I get the following error:
>
> Exception while processing message: java.lang.ClassCastException:
> org.drools.common.DefaultFactHandle cannot be cast to
> org.drools.common.EventFactHandle
> java.lang.ClassCastException: org.drools.common.DefaultFactHandle cannot be
> cast to org.drools.common.EventFactHandle
> at
>
> org.drools.rule.SlidingTimeWindow.updateNextExpiration(SlidingTimeWindow.java:192)
> at
>
> org.drools.rule.SlidingTimeWindow.assertRightTuple(SlidingTimeWindow.java:119)
> at
> org.drools.rule.BehaviorManager.assertRightTuple(BehaviorManager.java:87)
> at org.drools.reteoo.ExistsNode.assertObject(ExistsNode.java:172)
> at
>
> org.drools.reteoo.CompositeObjectSinkAdapter.doPropagateAssertObject(CompositeObjectSinkAdapter.java:366)
> at
>
> org.drools.reteoo.CompositeObjectSinkAdapter.propagateAssertObject(CompositeObjectSinkAdapter.java:349)
> at org.drools.reteoo.AlphaNode.assertObject(AlphaNode.java:147)
> at
>
> org.drools.reteoo.SingleObjectSinkAdapter.propagateAssertObject(SingleObjectSinkAdapter.java:42)
> at
> org.drools.reteoo.ObjectTypeNode.assertObject(ObjectTypeNode.java:184)
> at
> org.drools.reteoo.EntryPointNode.assertObject(EntryPointNode.java:146)
> at
>
> org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:1066)
> at
>
> org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:1022)
> at
>
> org.drools.common.AbstractWorkingMemory.insert(AbstractWorkingMemory.java:810)
> at
>
> com.s2grupo.triton.service.impl.CorrelatorServiceImpl.insertFact(CorrelatorServiceImpl.java:64)
> at
>
> com.s2grupo.triton.jms.impl.JmsMessageListenerImpl.onMessage(JmsMessageListenerImpl.java:67)
> at
>
> org.apache.activemq.ActiveMQMessageConsumer.dispatch(ActiveMQMessageConsumer.java:1021)
> at
>
> org.apache.activemq.ActiveMQSessionExecutor.dispatch(ActiveMQSessionExecutor.java:122)
> at
>
> org.apache.activemq.ActiveMQSessionExecutor.iterate(ActiveMQSessionExecutor.java:192)
> at
>
> org.apache.activemq.thread.PooledTaskRunner.runTask(PooledTaskRunner.java:122)
> at
> org.apache.activemq.thread.PooledTaskRunner$1.run(PooledTaskRunner.java:43)
> at
>
> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
> at
>
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
> at java.lang.Thread.run(Thread.java:619)
>
> What I'm missing? Is it a bug? I'm using the 5.0.0.SNAPSHOT version of
> drools.
>
> Thanks,
>
> NEStor
>
>
> ober0n wrote:
> >
> > Hi Ed, thanks for the quick reply, I will try the temporal constraints as
> > well.
> >
> > I haven't completed my testing yet but the sliding windows seems to be
> > working. Thanks!
> >
> > I am getting a strange problem of my program hanging. It gets all the way
> > past my "dispose()" of the StatefulKnowledgeSession and closing the
> > session logger and to the end of my main(). Then it just sits there. I'm
> > thinking it's a bug in my rules but wanted to make sure this wasn't a
> > feature of Streams (maybe some thread kicked off to accept facts or
> > something).
> >
> > If you could just confirm nothing in Drools fusion is supposed to
> continue
> > running, that would be great.
> >
> > Here are the significant snippets of my code:
> > ...
> > WorkingMemoryEntryPoint eventStream =
> > ksession.getWorkingMemoryEntryPoint( "EventStream" );
> > ...
> > eventStream.insert(goodbye_message);
> > Thread.sleep(10000);
> > eventStream.insert(hello_message);
> > ksession.fireAllRules();
> > ksession.dispose();
> > logger.close();
> > } catch (Throwable t) {
> > t.printStackTrace();
> > }
> > } // end main() <-- tracing through the code, I get past the end of
> > main() then see a "Source not found." in the Eclipse debugger which seems
> > to be looking for "Thread.exit() line: 604"
> >
> >
> > The updated rule:
> >
> > declare Message
> > @role( event )
> > end
> >
> > rule "Hello World"
> > when
> > Message( status == Message.HELLO ) from entry-point
> "EventStream"
> > exists(Message( status == Message.GOODBYE ) over
> window:time( 4s ) from
> > entry-point "EventStream")
> > then
> >
> > System.out.println("**************************************************");
> > System.out.println( "There was a GOODBYE message near the
> HELLO
> > message." );
> >
> > System.out.println("**************************************************");
> > end
> >
> > Thanks.
> >
> >
> > Edson Tirelli-3 wrote:
> >>
> >> Although your rule should work, the best way to write your rule
> would
> >> be
> >> using temporal constraints instead of sliding windows:
> >>
> >> rule "Goodbye before Hello World"
> >> when
> >> $m : Message( status == Message.HELLO )
> >> exists( Message( status == Message.GOODBYE, this
> >> before[0s,3s] $m ) )
> >> then
> >> System.out.println( "There was a GOODBYE message before
> >> the
> >> HELLO
> >> message." );
> >> end
> >>
> >> Using "before" operator is not only much cheaper (in terms of used
> >> resources) than sliding windows, but it also allow the engine to reason
> >> over
> >> the temporal constraints looking for special cases, like when you use
> >> negative patterns.
> >>
> >> I will look further into your case to check if I missed anything on
> >> the
> >> sliding windows support, but using STREAM mode should work.
> >>
> >> If you can open a JIRA for me to raise a compilation error when
> >> compiling sliding windows using CLOUD mode, I appreciate. This will
> allow
> >> you to follow up my progress.
> >>
> >> []s
> >> Edson
> >>
> >>
> >> 2009/3/30 ober0n <lili339 at hotmail.com>
> >>
> >>>
> >>> Hi Ed, no need to apologize, you have been invaluable in my first steps
> >>> towards Drooling :-D so thanks for all your help, it is GREATLY
> >>> appreciated
> >>> :clap:.
> >>>
> >>> We have a few scenarios in mind but aren't really implementing them
> yet,
> >>> just trying to see if sliding windows works the way we think it does.
> In
> >>> the
> >>> simple rule I wrote above, I basically want to check if two facts are
> >>> temporally close.
> >>>
> >>> Yes, you are correct. I didn't pay enough attention to the manual and
> >>> didn't
> >>> use STREAM mode to enter in my facts. I will use the manual insertion
> >>> process found in "Example 2.10. Inserting facts into an entry point" of
> >>> section "2.3. Streams Support" to update my code. And, I will update my
> >>> rule
> >>> to specify a "from entry-point <Specific Stream>".
> >>>
> >>> Also, could you comment on the simple rule I am using? Does it look
> like
> >>> it
> >>> should work after I do the updates? Or is my logic incorrect?
> >>>
> >>> Thanks again.
> >>>
> >>>
> >>>
> >>> Ober0n,
> >>>
> >>> Sorry for the delay on answering. I am on a trip with limited
> internet
> >>> connection.
> >>> I am interested in your experience with the sliding windows, since
> the
> >>> tests are working. Maybe it is a scenario not covered by the tests.
> >>>
> >>> In any case, what is probably happening is that you are not
> >>> configuring
> >>> the engine to work in STREAM mode. The default mode is CLOUD and it
> does
> >>> not
> >>> support sliding windows. It seems the engine is silently failing in
> this
> >>> case, when the compiler raise an error to warn the user.
> >>>
> >>> I just committed some docs on this subject:
> >>>
> >>>
> >>>
> https://hudson.jboss.org/hudson/job/drools/lastSuccessfulBuild/artifact/trunk/target/docs/drools-fusion/html/ch02.html#d0e1067
> >>>
> >>> (plz, wait for hudson to rebuild the docs or build docs yourself).
> >>>
> >>> Feedback welcome. I will complement the sliding window docs.
> >>>
> >>> []s
> >>> Edson
> >>>
> >>> 2009/3/29 ober0n <lili339 at hotmail.com>
> >>>
> >>> >
> >>> > Still trying to get sliding windows to work (basing my code off of
> the
> >>> > Eclipse supplied "Hello World" example). I don't think I fully
> >>> understand
> >>> > how it works yet so I'm trying to simplify things even further by
> >>> writing
> >>> > a
> >>> > simple rule that is meant to say:
> >>> >
> >>> > if (current_message = "Hello" AND exists( goodbye_message within
> >>> > sliding_window(3 seconds) ))
> >>> > then print("There was a GOODBYE message before the HELLO message." )
> >>> >
> >>> > In other words: This rule should fire if the current Hello World
> >>> message
> >>> > was
> >>> > preceeded within 3 seconds by a goodbye message.
> >>> >
> >>> >
> >>> >
> >>>
> ---------------------------------------------------------------------------------------------------
> >>> > I wrote a new rule for this:
> >>> >
> >>> > declare Message
> >>> > @role( event )
> >>> > end
> >>> >
> >>> > rule "Goodbye before Hello World"
> >>> > when
> >>> > Message( status == Message.HELLO )
> >>> > exists( Message( status == Message.GOODBYE ) over
> >>> > window:time( 3s ) )
> >>> > then
> >>> > System.out.println( "There was a GOODBYE message
> before
> >>> the
> >>> > HELLO
> >>> > message." );
> >>> > end
> >>> >
> >>> >
> >>> >
> >>>
> ---------------------------------------------------------------------------------------------------
> >>> >
> >>> > To send the messages: (ksession is a StatefulKnowledgeSession)
> >>> >
> >>> > ...
> >>> > ksession.insert(goodbye_message);
> >>> > ksession.fireAllRules();
> >>> >
> >>> > Thread.sleep(5000);
> >>> >
> >>> > ksession.insert(hello_message);
> >>> > ksession.fireAllRules();
> >>> > ...
> >>> >
> >>> >
> >>>
> ---------------------------------------------------------------------------------------------------
> >>> >
> >>> > I expect to get nothing back since I sent the Hello message 5 seconds
> >>> > after
> >>> > the goodbye message (outside the sliding window of 3 seconds). But,
> >>> for
> >>> > some
> >>> > reason the rule fires and I get one:
> >>> >
> >>> > "There was a GOODBYE message before the HELLO message."
> >>> >
> >>> > Any help would be greatly appreciated.
> >>> >
> >>> > Thanks!
> >>> > --
> >>> > View this message in context:
> >>> >
> >>>
> http://www.nabble.com/Trying-to-get-Sliding-Windows-to-work-tp22735051p22770318.html
> >>> > Sent from the drools - user mailing list archive at Nabble.com.
> >>> >
> >>> > _______________________________________________
> >>> > rules-users mailing list
> >>> > rules-users at lists.jboss.org
> >>> > https://lists.jboss.org/mailman/listinfo/rules-users
> >>> >
> >>>
> >>>
> >>>
> >>> --
> >>> Edson Tirelli
> >>> JBoss Drools Core Development
> >>> JBoss, a division of Red Hat @ www.jboss.com
> >>>
> >>> _______________________________________________
> >>> rules-users mailing list
> >>> rules-users at lists.jboss.org
> >>> https://lists.jboss.org/mailman/listinfo/rules-users
> >>>
> >>>
> >>>
> >>> --
> >>> View this message in context:
> >>>
> http://www.nabble.com/Trying-to-get-Sliding-Windows-to-work-tp22735051p22785711.html
> >>> Sent from the drools - user mailing list archive at Nabble.com.
> >>>
> >>> _______________________________________________
> >>> rules-users mailing list
> >>> rules-users at lists.jboss.org
> >>> https://lists.jboss.org/mailman/listinfo/rules-users
> >>>
> >>
> >>
> >>
> >> --
> >> Edson Tirelli
> >> JBoss Drools Core Development
> >> JBoss, a division of Red Hat @ www.jboss.com
> >>
> >> _______________________________________________
> >> rules-users mailing list
> >> rules-users at lists.jboss.org
> >> https://lists.jboss.org/mailman/listinfo/rules-users
> >>
> >>
> >
> >
>
> --
> View this message in context:
> http://www.nabble.com/Trying-to-get-Sliding-Windows-to-work-tp22735051p22844999.html
> Sent from the drools - user mailing list archive at Nabble.com.
>
> _______________________________________________
> rules-users mailing list
> rules-users at lists.jboss.org
> https://lists.jboss.org/mailman/listinfo/rules-users
>
--
Edson Tirelli
JBoss Drools Core Development
JBoss, a division of Red Hat @ www.jboss.com
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