I have an exception in android application and i don't know the reason?

the exception is

11-30 22:53:18.017: ERROR/Zygote(32): setreuid() failed. errno: 2
11-30 22:53:27.508: ERROR/Zygote(32): setreuid() failed. errno: 17
11-30 22:53:29.578: ERROR/BatteryService(65): usbOnlinePath not found
11-30 22:53:29.578: ERROR/BatteryService(65): batteryVoltagePath not found
11-30 22:53:29.578: ERROR/BatteryService(65): batteryTemperaturePath not found
11-30 22:53:29.618: ERROR/SurfaceFlinger(65): Couldn't open /sys/power/wait_for_fb_sleep or /sys/power/wait_for_fb_wake
11-30 22:53:36.538: ERROR/EventHub(65): could not get driver version for /dev/input/mouse0, Not a typewriter
11-30 22:53:36.538: ERROR/EventHub(65): could not get driver version for /dev/input/mice, Not a typewriter
11-30 22:53:36.708: ERROR/System(65): Failure starting core service
11-30 22:53:36.708: ERROR/System(65): java.lang.SecurityException
11-30 22:53:36.708: ERROR/System(65):     at android.os.BinderProxy.transact(Native Method)
11-30 22:53:36.708: ERROR/System(65):     at android.os.ServiceManagerProxy.addService(ServiceManagerNative.java:146)
11-30 22:53:36.708: ERROR/System(65):     at android.os.ServiceManager.addService(ServiceManager.java:72)
11-30 22:53:36.708: ERROR/System(65):     at com.android.server.ServerThread.run(SystemServer.java:184)
11-30 22:53:38.058: ERROR/SoundPool(65): error loading /system/media/audio/ui/Effect_Tick.ogg
11-30 22:53:38.058: ERROR/SoundPool(65): error loading /system/media/audio/ui/KeypressStandard.ogg
11-30 22:53:38.068: ERROR/SoundPool(65): error loading /system/media/audio/ui/KeypressSpacebar.ogg
11-30 22:53:38.068: ERROR/SoundPool(65): error loading /system/media/audio/ui/KeypressDelete.ogg
11-30 22:53:38.088: ERROR/SoundPool(65): error loading /system/media/audio/ui/KeypressReturn.ogg
11-30 22:53:41.837: ERROR/ThrottleService(65): Could not open GPS configuration file /etc/gps.conf
11-30 22:53:43.177: ERROR/logwrapper(143): executing /system/bin/tc failed: No such file or directory
11-30 22:53:43.25开发者_运维百科7: ERROR/logwrapper(145): executing /system/bin/tc failed: No such file or directory
11-30 22:53:43.347: ERROR/logwrapper(147): executing /system/bin/tc failed: No such file or directory
11-30 22:53:58.014: ERROR/HierarchicalStateMachine(65): TetherMaster - unhandledMessage: msg.what=3
11-30 22:55:39.283: ERROR/AndroidRuntime(272): FATAL EXCEPTION: main
11-30 22:55:39.283: ERROR/AndroidRuntime(272): java.lang.RuntimeException: Unable to start activity ComponentInfo{ayanoo.forms/ayanoo.forms.FriendsActivity}: java.lang.NullPointerException
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.os.Looper.loop(Looper.java:123)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.ActivityThread.main(ActivityThread.java:4627)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at java.lang.reflect.Method.invokeNative(Native Method)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at java.lang.reflect.Method.invoke(Method.java:521)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at dalvik.system.NativeStart.main(Native Method)
11-30 22:55:39.283: ERROR/AndroidRuntime(272): Caused by: java.lang.NullPointerException
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at ayanoo.forms.FriendsActivity.createLetters(FriendsActivity.java:54)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at ayanoo.forms.FriendsActivity.initLayout(FriendsActivity.java:43)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at ayanoo.forms.FriendsActivity.onCreate(FriendsActivity.java:31)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     ... 11 more

Look at the bottom of the error text; there's the answer:

11-30 22:55:39.283: ERROR/AndroidRuntime(272): Caused by: java.lang.NullPointerException
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at ayanoo.forms.FriendsActivity.createLetters(FriendsActivity.java:54)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at ayanoo.forms.FriendsActivity.initLayout(FriendsActivity.java:43)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at ayanoo.forms.FriendsActivity.onCreate(FriendsActivity.java:31)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11-30 22:55:39.283: ERROR/AndroidRuntime(272):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)

I couldn't help you further unless you post your code.