I'm not sure about the rationale of the Drools devs, but I can give an example of that design pattern from another rules package.
At my workplace (Southwest Airlines) we use Tibco BusinesEvents, and BE has the concept of Channels with Destinations that produce Events. A Channel can be mapped to various message producers (we mainly use JMS topics and queues) and our internal event types are mapped to the message types inside the Destination. This design pattern can be useful because often data with the same format can come from different sources, and the application may want to react differently mattering on the source. Also, there may be reasons you can't or don't want to include that source information in the data itself. For example, my current work deals with the airline's flight schedule, and reacting to daily changes in that schedule. We get RouteChange messages from various sources. (Sometimes due to a flight cancellation, and other times due to a flight addition.) We react differently to a RouteChange mattering on the reason, but the reason isn't encapsulated in the message, it's in the source. Thus it's nice to have multiple WM entry points, as otherwise we'd need yet another translation layer to inject a source marker into our RouteChangeEvent. GreG --- On Fri, 3/27/09, Wolfgang Laun <wolfgang.l...@gmail.com> wrote: > From: Wolfgang Laun <wolfgang.l...@gmail.com> > Subject: [rules-users] org.drools.runtime.rule.WorkingMemoryEntryPoint > To: "Rules Users List" <rules-users@lists.jboss.org> > Date: Friday, March 27, 2009, 12:26 PM > Where would I find information about the rationale of having > multiple named > WM entry points? > > Thanks > -W > _______________________________________________ > rules-users mailing list > rules-users@lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ rules-users mailing list rules-users@lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users
