Hi Michael,
Thanks for the heads-up, sounds like we'll have to change the locks.
- Don
On May 5, 2009, at 1:23 PM, Newcomb, Michael-P57487 wrote:
> The latest versions of jdk 1.6 (with at least update 11+) have
> changed some AWT methods that cause deadlock with OpenMap.
>
> When DTEDWorker finishes, it:
> 1. calls workerComplete(), which locks the DTEDLayer
> 2. calls repaint()
> 3. repaint() snakes its way up to BufferedLayer.BLMapBean.repaint()
> 4. that calls hasLayers() which in turn calls countComponents()
>
> Container.countComponents(), sometime between update 7 and update
> 11, changed to actually go through and count the components instead
> of returning a cached size. This locks the AWTTreeLock and causes a
> deadlock with normal repaint() code coming down and locking the
> AWTTreeLock.
>
> Normal paint():
> 1. locks AWTTreeLock as it is painting it's children
> 2. calls DTEDLayer.paint()
> 3. which calls getGraphicsList() which locks the DTEDLayer
>
> So, the deadlock occurs when the AWT thread locks the AWTTreeLock
> and *then* tries to lock the DTEDLayer object on getGraphicsList().
> But the DTEDWorker locks the DTEDLayer *then* tries to lock the
> AWTTreeLock.
>
> I don't think this will be isolated to DTEDLayer because I think
> there are patterns like this all throughout OpenMap.
>
> Thanks,
> Michael
>
--
[To unsubscribe to this list send an email to "majdart_at_bbn.com"
with the following text in the BODY of the message "unsubscribe openmap-users"]
Received on Wed May 06 2009 - 10:30:31 EDT