Question

I am working on application which is host on android market. Sometimes (once a month ) I got a crash report:

Unable to instantiate application java.lang.ClassNotFoundException

App downloads are between 10,000-50,000. I don’t know why this exceptions raise on some devices not all ( I tested it on 3 different devices & I couldn’t re-produce it at my end).

I read articles/suggestions on different android forums regarding the issue but I didn’t succeed in solving it. Does anyone face similar issue & suggest me what should I do?

Note:
I am extending application class like this

public class MyApplication extends Application {

}

I register it in the manifest.xml like this

<application android:icon="@drawable/app_icon"
    android:label="@string/my_app_name" android:name="MyApplication">

Stack Trace :

java.lang.RuntimeException: Unable to instantiate application  com.xyz.MyApplication      java.lang.ClassNotFoundException: com.xyz.MyApplication in loader dalvik.system.PathClassLoader[/mnt/asec/com.xyz-1/pkg.apk]
at android.app.ActivityThread$PackageInfo.makeApplication(ActivityThread.java:650)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4238)
at android.app.ActivityThread.access$3000(ActivityThread.java:126)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2076)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4633)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassNotFoundException: com.xyz.MyApplication in loader dalvik.system.PathClassLoader[/mnt/asec/com.xyz-1/pkg.apk]
at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
at android.app.Instrumentation.newApplication(Instrumentation.java:942)
at android.app.ActivityThread$PackageInfo.makeApplication(ActivityThread.java:645)

I don’t know why application crash on some devices not all.

Answer 1

I think the problem is with getApplication() which I have used in 10 different place. So I have used singleton pattern to solve this.

public class MyApplication extends Application {
    private static MyApplication me;

    @Override
    public void onCreate() {        
        super.onCreate();
        me = this ;

    }
    public static MyApplication getInstance() {
         return me;
    }
}

Now I have used getApplication() like this

     MyApplication application = MyApplication.getInstance();

insted of

     MyApplication application = (MyApplication) getApplication();

I have uploaded the fixed version on the market & now waiting if there is anymore this kind of crash. If everything goes perfect ( if no more crash in 2 weeks) then I will close the question. In meanwhile anyone has better idea or know the solution , please share it.
Thanks,