I would look at Observable and Observer class in java to achieve signal
sort of behavior.
On Tue, Feb 26, 2013 at 5:47 PM, Nigel Sheridan-Smith <wtfi...@gmail.com>wrote:
> Hi all,
>
> I'm hooking up a data import batch job with Quartz to Wicket and have
> struck an issue - how do you notify a Wicket page that the batch job is
> complete?
>
> I originally planned to update the Wicket session with the running count of
> how many items are processed. However, the Wicket request cycle expires so
> it is not possible to update the session after the page is rendered.
>
>
> To create the job:
>
> JobDataMap dataMap = new JobDataMap();
> > dataMap.put("service", getService());
> > dataMap.put("deck", deck);
> > dataMap.put("importType", importType);
> > dataMap.put("fieldMapping", fieldMapping);
> > dataMap.put("fileUploaded", fileUploaded);
> > dataMap.put("totalRecords", prevImportSummary.totalRecordsInImport);
> > dataMap.put("callback", this);
> > // Create a new job with a basic trigger
> > JobDetail job = newJob(DataImportJob.class
> > ).usingJobData(dataMap).build();
> > Trigger trigger =
> > newTrigger().startNow().withSchedule(simpleSchedule()).build();
> > try {
> > // Schedule the job for immediate start
> > TorScheduler.getScheduler().scheduleJob(job, trigger);
> > } catch (SchedulerException se) {
> > TorScheduler.getLogger().error(se.getMessage());
> > throw new TorException("Cannot start the data import job");
> > }
>
> The data import job uses a callback to the Wicket page:
>
> callback.updateTotal(totalRecords);
> >
> callback.updateProgress(/* 0 */ totalRecords, false); // TODO:
> > Temporarily skip the progress bar page
> >
>
> >
> // Now add the entries to the repository
> >
> ImportSummary importSummary = dataImportProcess.commit(callback);
> >
> callback.updateImportSummary(importSummary);
> >
>
> The callback has this implementation (in the page):
>
> public void updateProgress(int count, boolean error) {
> >
> > // Attempt to reuse the same session as before (left open)
> >
> > session.setAttribute("importItemsDone", (Integer) count);
> >
> > session.setAttribute("importIsInError", (Boolean) error);
> >
> > }
> >
> > @Override
> >
> > public void updateTotal(int total) {
> >
> >
> > // Attempt to reuse the same session as before (left open)
> >
> > session.setAttribute("importItemsTotal", (Integer) total);
> >
> > }
> >
> >
> > @Override
> >
> > public void updateImportSummary(ImportSummary importSummary) {
> >
> >
> > // Attempt to reuse the same session as before (left open)
> >
> > session.setAttribute("importSummary", importSummary);
> >
> > }
> >
>
> However, I get this exception when attempting to update the Wicket session
> with the progress counter:
>
> java.lang.IllegalStateException: Cannot set the attribute: no RequestCycle
> available. If you get this error when using WicketTester.startPage(Page),
> make sure to call WicketTester.createRequestCycle() beforehand.
> at org.apache.wicket.Session.setAttribute(Session.java:773)
> at
>
> com.xxx.tor.webapp.profile.Wiz13ImportResults.updateTotal(Wiz13ImportResults.java:208)
> at com.xxx.tor.webapp.batch.DataImportJob.importNow(DataImportJob.java:53)
> at com.xxx.tor.webapp.batch.DataImportJob.execute(DataImportJob.java:83)
> at org.quartz.core.JobRunShell.run(JobRunShell.java:213)
> at
>
> org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:557)
>
>
> Is this the best approach? Or should I attempt to use methods on the Quartz
> scheduler to get the current progress of the batch job from within
> AbstractAjaxTimerBehavior.onTimer( )?
>
> I am using the JQWicket (jQuery UI) progress bar... with a 5 second delay
> on updates to the page.
>
> Cheers,
>
> Nigel
>
>
> --
> e: ni...@joinsomeone.com
> m: +61 403 930 963
>
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