SwingWorker's done() not being executed

Question

The done() method not being executed after doInBackground() is finished.

I have the following code:

public class collectingWorker_USB4Java_Async_Fast extends SwingWorker<Void, Void> {     

    collectingWorker_USB4Java_Async_Fast(String name) {
        //initialize
        collectingWorkerDone = false;
    }

    @Override
    public Void doInBackground() {    

        loop = true;  

        while(loop){  
            collectData();                
            try {
                synchronized(TransferCallbackData) {
                    TransferCallbackData.wait();
                }
            } catch (InterruptedException ex) {
                Logger.getLogger(GraphPanel_JChart2D.class.getName()).log(Level.SEVERE, null, ex);
            }       
        }
        System.out.println("Out of the loop of collecting worker, loop: " + loop);
        return null;
    }  


    @Override
    protected void done() {
        collectingWorkerDone = true;
        System.out.println("Collecting worker DONE"); 
    }
}

But for some reason it is not executed after the doInBackground() is finished.

I have the worker in a while loop. To finished it I just set a boolean (loop) to false.

public void StartPlotting(){      
    Graphs.createCollectingThread();
    Graphs.collectWorker_usb4java_async_fast.execute();
}        

public void StopPlotting(){ 
    if (Graphs.collectWorker_usb4java_async_fast != null){
        if (Graphs.collectWorker_usb4java_async_fast.getState() == SwingWorker.StateValue.STARTED){
            Graphs.collectWorker_usb4java_async_fast.loop = false;
        }
        //wait until plotting is done
        synchronized(Graphs.collectWorker_usb4java_async_fast.TransferCallbackData){
            Graphs.collectWorker_usb4java_async_fast.TransferCallbackData.notify();
        }
        while(Graphs.collectWorker_usb4java_async_fast.getState() != SwingWorker.StateValue.DONE){
            synchronized(Graphs.collectWorker_usb4java_async_fast.TransferCallbackData){
                Graphs.collectWorker_usb4java_async_fast.TransferCallbackData.notify();
            }
        }  
    }
}  

public void StopPlottingWithCheck(){  
    if (Graphs.collectWorker_usb4java_async_fast != null){
        if (Graphs.collectWorker_usb4java_async_fast.getState() == SwingWorker.StateValue.STARTED){
            Graphs.collectWorker_usb4java_async_fast.loop = false;
        }
        //wait until plotting is done
        synchronized(Graphs.collectWorker_usb4java_async_fast.TransferCallbackData){
            Graphs.collectWorker_usb4java_async_fast.TransferCallbackData.notify();
        }
        while(Graphs.collectWorker_usb4java_async_fast.getState() != SwingWorker.StateValue.DONE){
            synchronized(Graphs.collectWorker_usb4java_async_fast.TransferCallbackData){
                Graphs.collectWorker_usb4java_async_fast.TransferCallbackData.notify();
            }
        }  
    }
    while(Graphs.collectingWorkerDone != true){
        //wait unil transfers dont receive more data
    }
}

If StopPlotting() is called just like that, I get:

Collecting worker DONE

However, if I StopPlottingWithCheck() is called, the code stalls.

In debug mode, I can see that the done() method is executed as soon as StopPlotting() is finished, this leads me to think that I have an EDT synchronization issue or something similar.

Is there any way to ensure that the done() method is executed right away after doInBackground() is finished?

I think you're likely right that you have a synchronization problem, but you haven't presented enough information to confirm it. Supposing that your `SwingWorker` runs at all, I see no reason to doubt that its `done()` method is invoked at the proper time -- and on the EDT, as documented. If your implementation is not properly synchronized, however, then you might not see the effects of that from a different thread right away, and maybe not *ever*. — John Bollinger, Mar 27 '17 at 15:15
done method not executed or your variable collectingWorkerDone is not updated? — johnII, Mar 27 '17 at 15:17
Additionally, I suggest finding a different approach than busy loops for awaiting operations to complete. You might use `wait` / `notify`, or a `SynchronousQueue`, or other alternatives. — John Bollinger, Mar 27 '17 at 15:20
Thanks for your comments, I just edited the posted code as requested, I hope you can give me a light on this — Camilo Guevara, Mar 27 '17 at 16:20
Posible duplicate of this [Q&A](http://stackoverflow.com/q/7053865/230513). — trashgod, Mar 27 '17 at 18:58
How is `while(loop){` controlled? When is it set to `false`? — MadProgrammer, Mar 27 '17 at 20:52
@MadProgrammer, it is just manually set to false, and then sync object is continuously notified until the worker state is DONE. it is done in the StopPlotting() method above — Camilo Guevara, Mar 27 '17 at 21:14
Which is why you still will want to post a decent [mcve] if you want a decent solution. You've still not posted code that we can run, that has a main method, and that shows your problem for us — Hovercraft Full Of Eels, Mar 27 '17 at 21:55

SwingWorker's done() not being executed

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