Re: [rules-dev] Issue with ResourceChangeScanner

Michael, In this exact case I am not expecting the scanner to ever find an updated resource; however, the changeset is configured to read one resource from a URL and another from the classpath.  The resource from the URL is expected to change, but the one from the classpath is not.  We have a use case where we may need classpath resources to be scanned, but I'm not sure it will ever come up. Unfortunately I don't think that we can reference that resource any way other than the classpath at this moment, but we do have another workaround.  Previous to Drools 5 we had a custom way of refreshing our resources which I think we will go back to for now. Should I log a feature request for this change? Steve Ronderos rules-dev-bounces(a)lists.jboss.org wrote on 10/07/2009 05:29:56 PM: > [image removed] > > Re: [rules-dev] Issue with ResourceChangeScanner > > Michael Neale > > to: > > Rules Dev List > > 10/07/2009 05:31 PM > > Sent by: > > rules-dev-bounces(a)lists.jboss.org > > Please respond to Rules Dev List > > Hi Steve - I have seen that issue before reported by others. But you > just explained the cause ! - I don't often use the classpath scanner > myself, so never thought of that. > > Yes the lastModified being zero is a problem... > > OK, well I think perhaps the solution would be if lastModified is not > a valid value, to NOT use that to decide availablility. > > I think using a scanner on  a classpath resource is a bit unusual to > start with, but it is possible in various containers to dynamically > change the classpath, so it kind of technically makes sense. > > If I had things in the classpath, I would assume they are constant - > but I assume you are actually expecting the scan to pick up changes in > a future ? > > (in the meantime, if you can avoid the classpath one that problem > should go away). > > On Thu, Oct 8, 2009 at 5:53 AM, Steve Ronderos <steve.ronderos(a)ni.com&gt; > wrote: > > > > Hello Dev List, > > > > I encountered an issue today with my KnowledgeAgent removing resources > > from > > its RuleBase shortly after creating it.  I have the > > ResourceChangeScanner > > running in my application. > > > > I tracked the issue back to the scan() method in > > ResourceChangeScannerImpl. > >  It appears that the method is trying to identify resources that are no > > longer available and remove them from both the RuleBase and future > > scans. > >  To do this it is checking lastModified on the resource and on a result > > of 0 > > removing the resource.  The resources that I configured in my change-set > > definitely still exist, but due to URL handler implementation provided > > by my > > classloader, getLastModified always returns 0.  (The resource I'm > > retrieving > > is coming from a jar that is in my application's classpath and the URL > > handler implementation is oracle.classloader.SharedCodeSourceURL) > > > > Do you think it would be possible for the scan to identify unavailable > > resources some other way than with the lastModified? and then if > > lastModified is 0 maybe always or never update the resource? I'm not > > sure > > what the best approach to that would be, but removing resources when > > their > > lastModified is 0 seems incorrect to me. > > > > Thanks, > > > > Steve Ronderos > > _______________________________________________ > > rules-dev mailing list > > rules-dev(a)lists.jboss.org > > https://lists.jboss.org/mailman/listinfo/rules-dev > > > > > > > > -- > Michael D Neale > home: www.michaelneale.net > blog: michaelneale.blogspot.com > > _______________________________________________ > rules-dev mailing list > rules-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/rules-dev _______________________________________________ rules-dev mailing list rules-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-dev