As you have Level with a field date, you can access that point in time in milliseconds, using getTimeInMillis(). For the current time, you might insert an object of class Current with a member now of class Calendar. rule closest when Current( $now: now ) $level: Level( $value == 2, $date: date ) not $x: Level( Math.abs( $x.getDate().getTimeInMillis() - $now.getTimeInMillis() ) < Math.abs( $date.getTimeInMillis() - $now.getTimeInMillis() ) ) then // $level is the Level fact closest to Current with a level of 2 end Untested. If the long expression gives you trouble, try enclosing it in eval(...). -W On 11 March 2014 18:14, JChrist <io.christod(a)gmail.com&gt; wrote: > Hello everyone, > I was messing with drools v6.0.1.Final the past week and I have not been > able to completely understand how to integrate the rule engine to my > specification. > > For the needs of my project, I want to regularly insert some data in the > engine, similar to the following: > class Level { double value;Calendar date; } > this class contains some values at specific time points (both in the past > and in the future). > > I would like to be able create a decision table based on the "current" > time > (plus or minus a variable offset) and the value of the closest Level to > that > time point. > > For example, assuming it is '2014-11-03 19:10:00' and the level objects in > the session currently are: > '1.0 2014-11-03 18:00:00' and '2.0 2014-11-03 19:00:00', > > I would want a rule to say that if current level value is 2.0 then do some > stuff and it would make a match. > > I would really appreciate any help on how to overcome this issue, as well > as > any good examples/tutorials regarding this. > > Kind regards. > > > > > -- > View this message in context: > http://drools.46999.n3.nabble.com/Temporal-rules-in-decision-table-tp4028... > Sent from the Drools: User forum mailing list archive at Nabble.com. > _______________________________________________ > rules-users mailing list > rules-users(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

You can create a rule with a timer to update Current with the required frequency. rule "set current" timer (int: 1s 1s) no-loop when $c: Current() then modify( $c ){ setXYZ(whatever) } end On 11/03/2014, Ioannis Christodoulou <io.christod(a)gmail.com&gt; wrote: > Thanks a lot for the prompt reply and the detailed example! > It took me some time but I managed to convert it to a working xls decision > table. > > Now, I wanted to figure out how to automatically update the Current object > regularly, in order to re-calculate the rules over time. > My application is a java ee one. Would creating a @schedule on a singleton > method be a good solution, or is there another better advice for it? > > Thanks again! > > Ευχαριστώ πολύ, > Ιωάννης Χριστοδούλου > > > On Tue, Mar 11, 2014 at 8:50 PM, Wolfgang Laun > <wolfgang.laun(a)gmail.com&gt;wrote: > >> As you have Level with a field date, you can access that point in time in >> milliseconds, using getTimeInMillis(). For the current time, you might >> insert an object of class Current with a member now of class Calendar. >> >> rule closest >> when >> Current( $now: now ) >> $level: Level( $value == 2, $date: date ) >> not $x: Level( Math.abs( $x.getDate().getTimeInMillis() - >> $now.getTimeInMillis() ) < Math.abs( $date.getTimeInMillis() - >> $now.getTimeInMillis() ) ) >> then >> // $level is the Level fact closest to Current with a level of 2 >> end >> >> Untested. If the long expression gives you trouble, try enclosing it in >> eval(...). >> -W >> >> >> On 11 March 2014 18:14, JChrist <io.christod(a)gmail.com&gt; wrote: >> >>> Hello everyone, >>> I was messing with drools v6.0.1.Final the past week and I have not been >>> able to completely understand how to integrate the rule engine to my >>> specification. >>> >>> For the needs of my project, I want to regularly insert some data in the >>> engine, similar to the following: >>> class Level { double value;Calendar date; } >>> this class contains some values at specific time points (both in the >>> past >>> and in the future). >>> >>> I would like to be able create a decision table based on the "current" >>> time >>> (plus or minus a variable offset) and the value of the closest Level to >>> that >>> time point. >>> >>> For example, assuming it is '2014-11-03 19:10:00' and the level objects >>> in >>> the session currently are: >>> '1.0 2014-11-03 18:00:00' and '2.0 2014-11-03 19:00:00', >>> >>> I would want a rule to say that if current level value is 2.0 then do >>> some >>> stuff and it would make a match. >>> >>> I would really appreciate any help on how to overcome this issue, as >>> well >>> as >>> any good examples/tutorials regarding this. >>> >>> Kind regards. >>> >>> >>> >>> >>> -- >>> View this message in context: >>> http://drools.46999.n3.nabble.com/Temporal-rules-in-decision-table-tp4028... >>> Sent from the Drools: User forum mailing list archive at Nabble.com. >>> _______________________________________________ >>> rules-users mailing list >>> rules-users(a)lists.jboss.org >>> https://lists.jboss.org/mailman/listinfo/rules-users >>> >> >> >> _______________________________________________ >> rules-users mailing list >> rules-users(a)lists.jboss.org >> https://lists.jboss.org/mailman/listinfo/rules-users >> > _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users