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Oct 13, 2007 12:02pm
Medium Bug Labs team finsprings 268 posts

When I hit escape to close the VirtualBUG when my app is running I get a null pointer exception. I'm guessing it's trying to tell my service tracker that the menu service has gone away, but my service tracker is already gone at the this point or something. It doesn't do this if I start either the GPS or LCD on their own then kill the bug; just when I start both (to satisfy the requirements of my app). I thought at first it was because I wasn't calling close() on the OSGI ServiceTracker in my activator's stop method, but adding that call didn't change anything.

Will the next SDK include the source by default? That would make setting breakpoints and walking through this error case a little more straightforward? If it will, I'm inclined to hold off on troubleshooting this until then.

[Sat Oct 13 11:43:12 EDT 2007] [INFO] Received new REMOVE model change event for module GPS
STOPPING file:/home/dave/dev/eclipse/configuration/org.eclipse.osgi/bundles/171/1/.cp/jars/osgi.jar
STOPPING file:/home/dave/dev/eclipse/configuration/org.eclipse.osgi/bundles/171/1/.cp/jars/cg_event.jar
STOPPING file:/home/dave/dev/eclipse/configuration/org.eclipse.osgi/bundles/171/1/.cp/jars/cg_framework.jar
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/ch.ethz.iks.slp.jar
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.osgi.http.jar
[Sat Oct 13 11:43:12 EDT 2007] [INFO] Unregistered servlet at /service.
[Sat Oct 13 11:43:12 EDT 2007] [INFO] Unregistered servlet /program
[Sat Oct 13 11:43:13 EDT 2007] [INFO] Server received shutdown-message. Shutting down.
[Sat Oct 13 11:43:12 EDT 2007] [INFO] Unregistered servlet at /program.
[Sat Oct 13 11:43:13 EDT 2007] [INFO] Unregistered servlet /module
[Sat Oct 13 11:43:13 EDT 2007] [INFO] Unregistered servlet at /module.
[Sat Oct 13 11:43:13 EDT 2007] [INFO] Unregistered servlet /event
[Sat Oct 13 11:43:13 EDT 2007] [INFO] Unregistered servlet at /event.
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.bug.service.jar
[Sat Oct 13 11:43:13 EDT 2007] [INFO] Unregistered servlet at /service.
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.bug.program.jar
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.bug.base.jar
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.common.jar
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.bug.menu.jar
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.bug.module.jar
STOPPING file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.bug.event.jar
STOPPING file:/home/dave/dev/workspace2/.metadata/.plugins/com.buglabs.osgi.concierge.runtime/bundles/GpsLogger_1.0.2.jar
GpsLogger: activator stop
GpsLogger: activator stopped
java.lang.NullPointerException
at com.buglabs.util.trackers.PublicWSAdminTracker.removedService(PublicWSAdminTracker.java:59)

at org.osgi.util.tracker.ServiceTracker$Tracked.untrack(ServiceTracker.java:897)
at org.osgi.util.tracker.ServiceTracker.close(ServiceTracker.java:269)
at com.buglabs.bug.menu.Menu.stop(Menu.java:143)
at com.buglabs.bug.menu.Activator.stop(Activator.java:37)
at ch.ethz.iks.concierge.framework.BundleImpl.stopBundle(BundleImpl.java:502)
at ch.ethz.iks.concierge.framework.Framework$SystemBundle.setLevel(Framework.java:2293)
at ch.ethz.iks.concierge.framework.Framework$SystemBundle.access$0(Framework.java:2255)
at ch.ethz.iks.concierge.framework.Framework.shutdown(Framework.java:514)
at ch.ethz.iks.concierge.framework.Framework$1.run(Framework.java:2077)
org.osgi.framework.BundleException: Error stopping bundle Bundle [10]: file:/home/dave/dev/eclipse/plugins/com.buglabs.dragonfly.bug.kernel_1.0.0.226/kernel/com.buglabs.bug.menu.jar
at ch.ethz.iks.concierge.framework.BundleImpl.stopBundle(BundleImpl.java:509)
at ch.ethz.iks.concierge.framework.Framework$SystemBundle.setLevel(Framework.java:2293)
at ch.ethz.iks.concierge.framework.Framework$SystemBundle.access$0(Framework.java:2255)
at ch.ethz.iks.concierge.framework.Framework.shutdown(Framework.java:514)
at ch.ethz.iks.concierge.framework.Framework$1.run(Framework.java:2077)
Oct 14, 2007 6:15pm
Medium Bug Labs team finsprings 268 posts

This happens for me in another from-scratch app that isn’t using a TimerTask, so it at least doesn’t appear to be code that I’m adding that’s causing it.

Oct 15, 2007 9:47am
Medium Bug Labs team kgilmer 215 posts

finsprings,

There are various NPEs that pop up on shutdown and it’s probably nothing to do with your application. Yes, hold off on debugging until a new SDK build is released. We’re having a hard time with another issue related to OS X but expect something shortly.

Oct 24, 2007 9:55am
Medium Bug Labs team bcruskie 45 posts

I started seeing this NPE on my Linux box last month. A defect was opened but Ken+Team couldn’t reproduce the error. I will move this out to the public Bugzilla shortly.

Fin, I assume you are seeing this on your Linux machine?

Also I can reproduce the issue with the following steps with no Apps in my workspace:

STR:
1. From Dragonfly launch VB
2. Insert a GPS module in any slot
3. hit esc to exit the VB

Oct 24, 2007 10:26am
Img_missing_medium koolatron 52 posts

I see NPEs randomly when shutting down the bug, but it’s not consistent by any means and doesn’t seem to follow any pattern based on installed modules or loaded applications.

I didn’t pay it much attention because real hardware will never need to be shut down in the same manner as the virtual BUG, unless you’re powering it off, at which point an NPE during shutdown really doesn’t make a difference (unless it causes the shutdown process to hang).

Oct 24, 2007 10:27am
Medium Bug Labs team finsprings 268 posts

bcruskie

Fin, I assume you are seeing this on your Linux machine?

Yes, this is on a knoppmyth box (which is basically Debian Etch).
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