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Re: Concurrency and restarting tasks

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On Tuesday, February 26, 2013 9:58:28 AM UTC-5, Joerg Meier wrote:
> On Tue, 26 Feb 2013 06:32:28 -0800 (PST), me 2 wrote:
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> 
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> > I have an interesting (to me at least!) puzzle.
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> 
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> > I have a task that can take a long time that I need to run periodically.  I want to be able to cancel the execution of that task.  I've been looking at the Scheduler and Future objects, but I haven't seen how to cleanly stop, wait for a couple of seconds and restart the task on schedule.  And my task won't always take X seconds--sometimes it will generate exceptions or take longer or shorter or any number of other things.
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> > There are plenty of examples that show the first steps--setting up the schedule and canceling.  Restarting apparently is not as common.
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> As I understand, ThreadS are simply not made to be resumed after being
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> cancelled. What you want might simply not be possible. That being said, it
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> shouldn't be too hard to simply make a new Thread with your Runnable and
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> start that instead of restarting the cancelled one.
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> Alternatively, you can make your long running task somehow check for a
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> volatile flag and pause if it's set to something.
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> 
> Liebe Gruesse,
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> 		Joerg
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> 
> 
> -- 
> 
> Ich lese meine Emails nicht, replies to Email bleiben also leider
> 
> ungelesen.

Hey,

I suppose you are right.  That doesn't make much sense when you put it like that.

The problem is that I need an event to fire if the task doesn't complete in X seconds.  I guess I don't really care about canceling the thread--just getting the event to fire and then getting set up to attempt the task again.

The double setup with the two scheduled tasks--one to start and one to cancel--gets muddled after like the 4th iteration.

Hmmm....

I'll keep looking.
Me

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Concurrency and restarting tasks me 2 <winona_whitener@yahoo.com> - 2013-02-26 06:32 -0800
  Re: Concurrency and restarting tasks Roedy Green <see_website@mindprod.com.invalid> - 2013-02-26 06:47 -0800
  Re: Concurrency and restarting tasks Joerg Meier <joergmmeier@arcor.de> - 2013-02-26 15:58 +0100
    Re: Concurrency and restarting tasks me 2 <winona_whitener@yahoo.com> - 2013-02-26 08:09 -0800
      Re: Concurrency and restarting tasks Joerg Meier <joergmmeier@arcor.de> - 2013-02-26 18:14 +0100

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