824474 - java.lang.NullPointerException: at org.mozilla.gecko.TabsTray$TabsAdapter.removeTab(TabsTray.java)

Status: RESOLVED FIXED

(Firefox for Android Graveyard :: General, defect)

Description

[Robert Kaiser]

This bug was filed from the Socorro interface and is 
report bp-8c9e288b-4e4c-4dc1-b2c5-96c6e2121223 .
============================================================= 

Java exception message:

java.lang.NullPointerException
	at org.mozilla.gecko.TabsTray$TabsAdapter.removeTab(TabsTray.java:226)
	at org.mozilla.gecko.TabsTray$TabsAdapter.onTabChanged(TabsTray.java:156)
	at org.mozilla.gecko.Tabs$5.run(Tabs.java:374)
	at android.app.Activity.runOnUiThread(Activity.java:4170)
	at org.mozilla.gecko.Tabs.notifyListeners(Tabs.java:365)
	at org.mozilla.gecko.Tabs.notifyListeners(Tabs.java:361)
	at org.mozilla.gecko.Tab.onDestroy(Tab.java:110)
	at org.mozilla.gecko.Tabs.closeTab(Tabs.java:179)
	at org.mozilla.gecko.Tabs.closeTab(Tabs.java:163)
	at org.mozilla.gecko.TabsTray$3.onPropertyAnimationEnd(TabsTray.java:326)
	at org.mozilla.gecko.PropertyAnimator.stop(PropertyAnimator.java:158)
	at org.mozilla.gecko.PropertyAnimator.run(PropertyAnimator.java:96)
	at android.os.Handler.handleCallback(Handler.java:605)
	at android.os.Handler.dispatchMessage(Handler.java:92)
	at android.os.Looper.loop(Looper.java:137)
	at android.app.ActivityThread.main(ActivityThread.java:4514)
	at java.lang.reflect.Method.invokeNative(Native Method)
	at java.lang.reflect.Method.invoke(Method.java:511)
	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
	at dalvik.system.NativeStart.main(Native Method)

This started happening in 20.0a1 trunk on 2012-12-23.

Find more reports at https://crash-stats.mozilla.com/report/list?signature=java.lang.NullPointerException%3A%20at%20org.mozilla.gecko.TabsTray%24TabsAdapter.removeTab%28TabsTray.java%29

Comment 1

[Joe Drew (not getting mail)]

Happened to me as I closed a tab (I had a couple open at the time).

Comment 2

[Robert Kaiser]

I saw this myself today with the same scenario as comment 1, this is by far the top crash atm, and solely responsible for the high crash rate on Nightly.

Comment 3

[Sriram Ramasubramanian [:sriram]]

Is there any STR for this?

Comment 4

[Timothy Nikkel (:tnikkel)]

I don't have STR but I hit this more than once a day during normal browsing (I know, that doesn't help at all!).

Comment 5

[Timothy Nikkel (:tnikkel)]

And it's always when closing a tab when I have say around 4 or more tabs open.

Comment 6

[Sriram Ramasubramanian [:sriram]]

I just reproduced it. Should fix it soon. Stay tuned. :D

Comment 7

[Sriram Ramasubramanian [:sriram]]

Attachment: Patch

Some of the cases when this crashes could happen are:
1. Precondition: There is one normal tab and the tabs-tray is opened at least once. Open a private tab and open the tabs-tray. Now try closing the only private tab. This will crash, as we try to "hide()" the normal tabs. 
Fix: This is fixed in TabsPanel.java where we hide the previously switched tab contents, when we switch tabs.

2. Close the only available private tab. This closes the tabs-tray and informs Tabs not to send any more tab-changes. At this point, there could be a race where Tabs sends a notification for the closed tab and our adapter's tab-list is null.
Fix: Remove it from the adapter's list only it is not null.

Comment 8

[Sriram Ramasubramanian [:sriram]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/8f5e2129e89d

Comment 9

[Aaron Train [:aaronmt]]

Assuming the other bug 824354 is a dupe

Comment 11

[Naoki Hirata :nhirata (please use needinfo instead of cc)]

Sweet!  Thanks, Sriram.  This bug has caused Nightly to skyrocket in crashes.

Comment 12

[Daniel Holbert [:dholbert]]

https://hg.mozilla.org/mozilla-central/rev/8f5e2129e89d