February 21 2013 Thursday
DOTS Deep Dive 4: I can schedule myself...
Finally, we will be able to enable FeedMonster for CollaborationToday project.
While doing final touches, I have been challenged by a question: "Can we schedule DOTS tasklets programmatically?"
Actually, this is in the wish list for the next version of DOTS. But we can do some trick here. I didn't test this on Domino 9 but it should work.
Here is the code:
So it's simple. There is a ServerTaskManager singleton object which manages all tasklets. We are using ".schedule(...)" method (luckily it's public).
When we load DOTS:
You can use some kind of parameterization to customize your tasklet scheduling. For instance, I am planning to use this functionality for FeedMonster such that If there are only 5 feeds to be read, it's useless to receive new stories every 5 minutes. However, there is no way to 'unschedule' a tasklet. We'll find another trick for this.
ServerTaskManager is a great object BTW. For instance;
I didn't find it safe though. Since it doesn't submit a CommandInterpreter object, there might be a problem in error trapping. Noted to the list of feedbacks :)
While doing final touches, I have been challenged by a question: "Can we schedule DOTS tasklets programmatically?"
Actually, this is in the wish list for the next version of DOTS. But we can do some trick here. I didn't test this on Domino 9 but it should work.
Here is the code:
package org.openntf.news.playground.tasklets;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import com.ibm.dots.annotation.RunOnStart;
import com.ibm.dots.task.AbstractServerTaskExt;
import com.ibm.dots.task.RunWhen;
import com.ibm.dots.task.RunWhen.RunUnit;
import com.ibm.dots.task.ServerTaskManager;
public class CustomSchedule extends AbstractServerTaskExt {
@Override
public void dispose() {
}
@RunOnStart
public void scheduleMe(IProgressMonitor monitor) {
ServerTaskManager stm=ServerTaskManager.getInstance();
// Every 10 seconds
RunWhen sched=new RunWhen(RunUnit.second, 10, 0, 0);
try {
// custom01 is this tasklet's id as defined in plugin.xml
stm.scheduleTasklet("custom01", sched);
} catch (CoreException e) {
e.printStackTrace();
}
logMessage("I have scheduled myself for "+sched);
}
@Override
protected void doRun(RunWhen runWhen, IProgressMonitor monitor) {
logMessage("CustomSchedule: "+runWhen.toString());
}
}
So it's simple. There is a ServerTaskManager singleton object which manages all tasklets. We are using ".schedule(...)" method (luckily it's public).
When we load DOTS:
> load dots
Listening for transport dt_socket at address: 8001
21.02.2013 13:55:30 Domino OSGi Tasklet Container started ( profile DOTS )
21.02.2013 13:55:31 [DOTS] (custom01) I have scheduled myself for Runs every 10 - second
21.02.2013 13:55:33 [DOTS] (custom01) CustomSchedule: Runs every 10 - second
21.02.2013 13:55:43 [DOTS] (custom01) CustomSchedule: Runs every 10 - second
You can use some kind of parameterization to customize your tasklet scheduling. For instance, I am planning to use this functionality for FeedMonster such that If there are only 5 feeds to be read, it's useless to receive new stories every 5 minutes. However, there is no way to 'unschedule' a tasklet. We'll find another trick for this.
ServerTaskManager is a great object BTW. For instance;
stm.runTasklet("someTasklet", "argument1", "argument2"); I didn't find it safe though. Since it doesn't submit a CommandInterpreter object, there might be a problem in error trapping. Noted to the list of feedbacks :)
