Develop Reference

Rare Android Unable to Instantiate Application Exception

I'm seeing the following exception under Crashes in the dev console from time to time.
Whats puzzling about it is that google maps shows up in the call stack as if its calling or creating my app class - very confusing. Whats further weird is the "MyApp-2.apk" in the call stack - where it appends the "-2".
I do include the android.maps.jar file in the libs.
I would like to know how to recreate this if possible and how to prevent this from happening?
java.lang.RuntimeException: Unable to instantiate application com.MyApp.MyCustomApp:
java.lang.ClassNotFoundException: Didn't find class "com.MyApp.MyCustomApp"
on path: /system/framework/com.google.android.maps.jar:/data/app/com.MyApp-2.apk
at android.app.LoadedApk.makeApplication(LoadedApk.java:503)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4405)
at android.app.ActivityThread.access$1400(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1327)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5059)
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:792)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:555)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.MyApp.MyCustomApp" on path: /system/framework/com.google.android.maps.jar:/data/app/com.MyApp-2.apk
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
at android.app.Instrumentation.newApplication(Instrumentation.java:967)
at android.app.LoadedApk.makeApplication(LoadedApk.java:498)
... 11 more
Manifest Application Tag:
<application
android:name=".MyApp"
android:hardwareAccelerated="true"
android:icon="#drawable/app_icon"
android:label="#string/app_name"
android:theme="#style/AppBaseTheme" >
I'm using these JARS: android-support-v4-r2-googlemaps.jar + android-support-v4.jar

The prime reason why a Class within your application would be present on your test devices but missing at runtime on some others would be if your class has a dependency on some external feature which is missing on those devices. For example, if you used some Google API which is not part of AOSP and so missing on a plain AOSP build, or a vendor build which does not license these, then your class will be pruned at install time as its dependencies cannot be resolved.
A common reason for your app finding its way into such circumstances might be someone running an inconsistently assembled "custom ROM" on their device.

What could be causing a ClassNotFoundException?

So I've been working on an app lately which runs fine on most devices. However, sometimes the app crashes at start up with the following error:
java.lang.RuntimeException: Unable to instantiate activity
ComponentInfo{com.mypackage.app/com.mypackage.app.activities.MainPager}:
java.lang.ClassNotFoundException: com.mypackage.app.activities.MainPager
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1995)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2096)
at android.app.ActivityThread.access$600(ActivityThread.java:138)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1207)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:213)
at android.app.ActivityThread.main(ActivityThread.java:4787)
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:809)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:576)
at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:115)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassNotFoundException:
com.mypackage.app.activities.MainPager
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:61)
at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1986)
... 12 more
I get that this is because it can't find the class called MainPager. But how is that even possible? I mean, the class should be there.. I put it there myself :) . Why on earth is it not finding it?
EDIT: I think the cause may be that in my manifest I have android:package="com.mypackage.app" defined, but that my launch activity is in the package com.mypackage.app.activities. Currently testing this theory. Still weird that it only happens on some devices, though.
This solution won't work, since I then can't update the APK in Google Play (has to be the same package name in the manifest).

Since ADT update to revision 22 (May 2013) you have to check "Android Private Libraries" check box in Project -> Properties -> Java Build Path -> Order and Export in Eclipse for your older projects to get rid of this exception ...

in the manifest you add Activity name like this
android:name=".activities.MainPager"
because you have given package name
android:package="com.mypackage.app"

Now I am using ART runtime on Nexus 5, and I am getting ClassNotFound for some apps.
You can safely ignore those if that's the case for your users.

NoClassDefFoundError occured while initiate fragment

java.lang.NoClassDefFoundError occured at the first line:
FirstFragment firstTab = FirstFragment.newInstance(10);
mTabsAdapter.addTab(generateTabSpec(0, mTabHost),
firstTab.getClass(), null);
But I'm pretty sure the Fragment exist! (it's a fragment so don't need to check if declared in Manifest.) Even refactoring its name or move to other package didn't fix the problem. Here's the stacktrace:
ERROR/AndroidRuntime(23608): FATAL EXCEPTION: main
java.lang.NoClassDefFoundError: dev.twothree.android.wtf.FirstFragment
at dev.twothree.android.activity.FragmentTab.setupTabHost(FragmentTab.java:110)
at dev.twothree.android.activity.FragmentTab.onCreate(FragmentTab.java:75)
at android.app.Activity.performCreate(Activity.java:5008)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2136)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2207)
at android.app.ActivityThread.access$600(ActivityThread.java:139)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4899)
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:791)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:558)
at dalvik.system.NativeStart.main(Native Method)
Is it a bug of Intell J 12.0.4? My version is Build #IC-123.169. Later I'll try it in the Eclipse, but still hope it can be resolved in Intelli J.

After open the whole project with Eclipse, config all the dependencies ONCE AGAIN, Eclipse point out that I accidentally CAST one of the custom library class to another class. Maybe that's why no successful compiled class file existed for later invoke.
Anyway, it seems Intelli-J didn't found that error while 3rd party library is involved, it could be a bug. But the blame is also on me for not find that so obvious error.

How to resolve Exception during suite construction?

I have followed the below steps to test my app.
I have created Android Project.
I have created the debug signature for my sample app and test app(which need to be tested)
Place the sampleapp_debug.apk in the bin folder (where my workspace is there)
Installed the testapp_debug.apk in the emulator.
Now i am running the project as a Android JunitTest.
I am getting the below error.. How to resolve this..
java.lang.RuntimeException: Exception during suite construction
at android.test.suitebuilder.TestSuiteBuilder$FailedToCreateTests.testSuiteConstructionFailed(TestSuiteBuilder.java:239)
at java.lang.reflect.Method.invokeNative(Native Method)
at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:169)
at android.test.AndroidTestRunner.runTest(AndroidTestRunner.java:154)
at android.test.InstrumentationTestRunner.onStart(InstrumentationTestRunner.java:520)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1447)
Caused by: java.lang.NullPointerException: Method name must not be null.
at java.lang.ClassCache.findMethodByName(ClassCache.java:297)
at java.lang.Class.getMethod(Class.java:985)
at android.test.suitebuilder.TestMethod.getAnnotation(TestMethod.java:60)
at android.test.suitebuilder.annotation.HasMethodAnnotation.apply(HasMethodAnnotation.java:39)
at android.test.suitebuilder.annotation.HasMethodAnnotation.apply(HasMethodAnnotation.java:30)
at com.android.internal.util.Predicates$OrPredicate.apply(Predicates.java:106)
at android.test.suitebuilder.annotation.HasAnnotation.apply(HasAnnotation.java:42)
at android.test.suitebuilder.annotation.HasAnnotation.apply(HasAnnotation.java:31)
at com.android.internal.util.Predicates$NotPredicate.apply(Predicates.java:122)
at android.test.suitebuilder.TestSuiteBuilder.satisfiesAllPredicates(TestSuiteBuilder.java:254)
at android.test.suitebuilder.TestSuiteBuilder.build(TestSuiteBuilder.java:190)
at android.test.InstrumentationTestRunner.onCreate(InstrumentationTestRunner.java:373)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4218)
at android.app.ActivityThread.access$3000(ActivityThread.java:125)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2071)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4627)
at java.lang.reflect.Method.invokeNative(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
at dalvik.system.NativeStart.main(Native Method)

I faced similar type of problem before. I resolved the same by using default constructor in Testcode rather than parametrized constructor. The following tutorial was useful for me
See this tutorial

I encounter the same error and this solution worked for me:
Do not use public TestTextView(String name) but public TestTextView()
as constructor.
as what W.Elsinga mention on his comment found here Link

Your referenced code was way old.
Just add default constructor.
public StartActivityTest() {
super(StartActivity.class);
}

I think the problem at method: android.test.suitebuilder.TestMethod.getAnnotation().
Try to call the method setName() at constructor of the activity.
See: RuntimeException while using ActivityUnitTestCase, but not while ActivityInstrumentationTestCase2
The exception is caused by android.test.suitebuilder.TestMethod.getAnnotation(), too.

Error When creating an Application class in Android

I followed the advice given on the internet regarding working with Application classes in android.
I also added a field "android:name=.Session" to my Application object in the manifest.
The application is called "Session".
What do you think is the error? This is happening even before the my App starts.
This is the error stack:
**java.lang.RuntimeException: Unable to instantiate application com.appfire.Session: java.lang.InstantiationException: com.appfire.Session**
at android.app.ActivityThread$PackageInfo.makeApplication(ActivityThread.java:523)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:3996)
at android.app.ActivityThread.access$2900(ActivityThread.java:119)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1901)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:123)
at android.app.ActivityThread.main(ActivityThread.java:4363)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:521)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
at dalvik.system.NativeStart.main(Native Method)
**Caused by: java.lang.InstantiationException: com.appfire.Session**
at java.lang.Class.newInstanceImpl(Native Method)
at java.lang.Class.newInstance(Class.java:1479)
at android.app.Instrumentation.newApplication(Instrumentation.java:957)
at android.app.Instrumentation.newApplication(Instrumentation.java:942)
at android.app.ActivityThread$PackageInfo.makeApplication(ActivityThread.java:518)

Make sure your Session class is public, is not static, and does not have a default constructor.
public class Session extends Application {}

In the Manifest application tag, make sure you include the fully-qualified class name of your custom Application object:
<application
android:name="com.mycompany.myapp.Session"
.... />
The Android docs do say the class name must be fully qualified:
http://developer.android.com/guide/topics/manifest/application-element.html#nm
(This is not the case for Activity class names that are included in the activity tag of the Manifest. Those can be relative, preceded with a '.').

My solution was to delete the whole project from Eclipse and load it again from SVN. Now it works