Exception in the Android's code while starting the app

Question

In the "Crashes and ANRs" of the Google Play Developer console I've got such a report:

java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.AssetManager android.content.res.Resources.getAssets()' on a null object reference
at android.app.LoadedApk.getAssets(LoadedApk.java:590)
at android.app.LoadedApk.makeApplication(LoadedApk.java:646)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:5088)
at android.app.ActivityThread.access$1600(ActivityThread.java:177)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1509)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:5944)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1389)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1184)

The device that has this problem is Galaxy S4 and runs Android 5.0

What it can be - there is not a single line from my code, why does it fail?

Thanks a lot!

Answer 1

I've got this in my console too. It seems this occurs when users start the app when it's currently being updated or just after that.

A possible workaround would be to check if getResources returns null when the application start, and kill it if it does:

public class DevToolsApplication extends Application { 
    private static final String TAG = "DevToolsApplication"; 

    @Override 
    public void onCreate() { 
        super.onCreate(); 
        AppLogger.i(TAG, "app start..."); 
        checkAppReplacingState(); 
    } 

    private void checkAppReplacingState() { 
        if (getResources() == null) { 
            AppLogger.w(TAG, "app is replacing...kill"); 
            Process.killProcess(Process.myPid()); 
        } 
    } 
} 

See this for more information https://issuetracker.google.com/issues/36972466