[rules-users] Query in stateless knowledge session returns no results
Heijink, Hank
heijink at audible.com
Sun Jul 31 13:07:54 EDT 2011
Thanks so much! I'll have a chance to test it tomorrow.
Hank
Sent from my iPhone
On Jul 31, 2011, at 12:48 PM, "Mark Proctor" <mproctor at codehaus.org<mailto:mproctor at codehaus.org>> wrote:
On 31/07/2011 17:45, Mark Proctor wrote:
On 31/07/2011 17:25, Heijink, Hank wrote:
Aha! I missed the line about the dispose. That makes a lot of sense. What I don't understand is why the example 3.37 in the docs would work. If I understand what you're saying, it shouldn't.
It should work, as long as the query is executed as part of the same execute batch. We have unit tests f or that too somewhere.
ok I see the problem. Your rules will not fire until the all the command shave been executed. i.e. the implicit fireAllRules() is once all commands have been executed. Which means the query will be invoked before your rule fires to insert the object.
Instead you need to add the FireAllRules command before executing the query.
Mark
mark
Thanks!
Hank
Sent from my iPhone
On Jul 30, 2011, at 8:27 AM, "Wolfgang Laun" <<mailto:wolfgang.laun at gmail.com>wolfgang.laun at gmail.com<mailto:wolfgang.laun at gmail.com>> wrote:
StatelessKnowledgeSession.execute(...) executes the command(s) and finally calls dispose() on the session. Use a stateful session or a global (filled with a low-salience rule) or - simply use the getObjects command.
-W
On 29 July 2011 22:47, Heijink, Hank <<mailto:heijink at audible.com>heijink at audible.com<mailto:heijink at audible.com>> wrote:
Hi all,
I'm new to Drools, so please excuse me if I'm asking about the obvious--it's certainly not obvious to me. The problem is this: I use a stateless knowledge session where a list of facts is inserted. The rules that fire create new facts, and after all the rules have fired, I'd like to obtain a list of all the facts (the old and the new). The best way seemed to use a query. I'm using Drools 5.1 on Linux.
This is part of my .drl file (without the imports):
rule "create badge"
when
Event ( eventType == EventType.SOME_EVENT_TYPE )
not BadgeState ( identifier == "badge" )
then
insert( new BadgeState("badge") );
end
query "all badges"
aBadge : BadgeState()
end
This is the Java code:
StatelessKnowledgeSession ksession = StatsKnowledgeBase.getKnowledgeBase().newStatelessKnowledgeSession();
// Create a list of share events
ArrayList<Event> events = new ArrayList<Event>();
Date now = new Date();
MobileDevice aDevice = new MobileDevice("uniqueId", "deviceType");
for (int i = 0; i < 5; i++) {
Event anEvent = new Event.Builder(now, aDevice, "aCustomer", EventType.SOME_EVENT_TYPE).build();
events.add(anEvent);
}
// Create the query for the badges
List<Command> commands = new ArrayList<Command>();
commands.add(CommandFactory.newInsertElements(events));
commands.add(CommandFactory.newQuery("all badges", "all badges"));
// Feed the events into Drools
KnowledgeRuntimeLogger logger = KnowledgeRuntimeLoggerFactory.newConsoleLogger(ksession);
ExecutionResults results = ksession.execute( CommandFactory.newBatchExecution(commands) );
NativeQueryResults queryResults = (NativeQueryResults)results.getValue("all badges");
// At this point, queryResults is empty.
logger.close();
// Get a list of badges
List<BadgeState> badges = new ArrayList<BadgeState>();
for (Iterator<QueryResultsRow> i = queryResults.iterator(); i.hasNext(); ) {
QueryResultsRow result = i.next();
BadgeState obj = (BadgeState)result.get("aBadge");
badges.add(obj);
}
The logger shows me that the BadgeState object is created, but the query returns an empty list. I've searched the documentation, which suggests that I'm doing it right (<http://drools.herod.net/drools-expert/html/ch03.html#d0e1956>http://drools.herod.net/drools-expert/html/ch03.html#d0e1956, example 3.37), the archives of this mailinglist, and the web, so far without success.
Clearly, I'm missing something, and I have the nagging feeling that it's something simple...
Any help is much appreciated!
Best,
Hank
_______________________________________________
rules-users mailing list
<mailto:rules-users at lists.jboss.org>rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
<https://lists.jboss.org/mailman/listinfo/rules-users>https://lists.jboss.org/mailman/listinfo/rules-users
_______________________________________________
rules-users mailing list
<mailto:rules-users at lists.jboss.org>rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
<https://lists.jboss.org/mailman/listinfo/rules-users>https://lists.jboss.org/mailman/listinfo/rules-users
_______________________________________________
rules-users mailing list
<mailto:rules-users at lists.jboss.org>rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
<https://lists.jboss.org/mailman/listinfo/rules-users>https://lists.jboss.org/mailman/listinfo/rules-users
_______________________________________________
rules-users mailing list
<mailto:rules-users at lists.jboss.org>rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
<https://lists.jboss.org/mailman/listinfo/rules-users>https://lists.jboss.org/mailman/listinfo/rules-users
_______________________________________________
rules-users mailing list
rules-users at lists.jboss.org<mailto:rules-users at lists.jboss.org>
https://lists.jboss.org/mailman/listinfo/rules-users
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.jboss.org/pipermail/rules-users/attachments/20110731/5a7cc444/attachment.html
More information about the rules-users
mailing list