Develop Reference

Android Package Name Dex Issue

I'm to trying create an application with package name "com.cvs.myapp". App builds perfectly but crashes in device at runtime.
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.cvs.myapp/com.cvs.myapp.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.cvs.myapp.MainActivity" on path: DexPathList[[zip file "/data/app/com.cvs.myapp-DG6fxWRjVXjsKQV_vwJwAw==/base.apk"],nativeLibraryDirectories=[/data/app/com.cvs.myapp-DG6fxWRjVXjsKQV_vwJwAw==/lib/x86, /system/lib]]
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2843)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3048)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
at android.os.Handler.dispatchMessage(Handler.java:106)
at android.os.Looper.loop(Looper.java:193)
at android.app.ActivityThread.main(ActivityThread.java:6669)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.cvs.myapp.MainActivity" on path: DexPathList[[zip file "/data/app/com.cvs.myapp-DG6fxWRjVXjsKQV_vwJwAw==/base.apk"],nativeLibraryDirectories=[/data/app/com.cvs.myapp-DG6fxWRjVXjsKQV_vwJwAw==/lib/x86, /system/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:134)
at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at android.app.AppComponentFactory.instantiateActivity(AppComponentFactory.java:69)
at androidx.core.app.CoreComponentFactory.instantiateActivity(CoreComponentFactory.java:41)
at android.app.Instrumentation.newActivity(Instrumentation.java:1215)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2831)
It's just a new project with no other additions containing only a MainActivity class. Same new project will work if i rename the package to "com.demo.myapp".
Using Analyse APK, I can see that the classes.dex file doesn't contain the MainActivity. Is the name "cvs" causing the issue as it will work perfectly with any other name instead of it?
gradle-wrapper.properties
distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.4-all.zip
build.gradle(project)
classpath 'com.android.tools.build:gradle:3.6.3'
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.cvs.myapp">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name="com.cvs.myapp.MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

As you mentioned this is happening when you are using the latest Gradle that is currently 3.6.3, It has a new packaging tool ZipFlinger, which might be causing the issue, try below code to disable it
android.useNewApkCreator=false
Moreover I got some relevant links, please have a look.
https://issuetracker.google.com/issues/150198184
After upgrading to android 3.6.1 apk cant be installed on devices
Android App runtime crash after update gradle plugin 3.6
MultiDex problem with Android Studio 3.6 when implementing it the right way

Fatal Exception - unable to instantiate activity - real application class is null

Trying to build and run an app in Android Studio 2.2.2 that does work in Eclipse. When I try to debug it (on a Samsung Galaxy tab 4) I get: (BTW is there any way to get this to come out more readably in StackOverflow?)
I/System.out: waiting for debugger to settle... I/System.out: debugger
has settled (1484) I/InstantRun: Instant Run Runtime started. Android
package is com.xxxxxxx.remote, real application class is null.
W/InstantRun: No instant run dex files added to classpath
D/AndroidRuntime: Shutting down VM E/AndroidRuntime: FATAL EXCEPTION:
main
Process: com.xxxxxxx.remote, PID: 1925
java.lang.RuntimeException: Unable to instantiate activity
ComponentInfo{com.xxxxxxx.remote/com.xxxxxxx.remote.RemoteControlActivity}:
java.lang.ClassNotFoundException: Didn't find class
"com.xxxxxxx.remote.RemoteControlActivity" on path: DexPathList[[zip
file
"/data/app/com.xxxxxxx.remote-1/base.apk"],nativeLibraryDirectories=[/vendor/lib,
/system/lib]]
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2644)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2867)
at android.app.ActivityThread.access$900(ActivityThread.java:181)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1476)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6134)
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:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.xxxxxxx.remote.RemoteControlActivity" on path:
DexPathList[[zip file
"/data/app/com.xxxxxxx.remote-1/base.apk"],nativeLibraryDirectories=[/vendor/lib,
/system/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
at android.app.Instrumentation.newActivity(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2634)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2867)
...etc...
I've "xxxxx"'ed out a proprietary name. What do real application class is null and No instant run dex files added to classpath mean? Also I see the reference to "Unable to instantiate activity ComponentInfo" in a lot of similar questions - what does it mean?
The activity it can't find is declared in the manifest as...
<activity android:launchMode="singleTask"
android:label="#string/app_name"
android:windowNoTitle="false"
android:configChanges="orientation"
android:screenOrientation="landscape"
android:name=".RemoteControlActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
I can't even hit a breakpoint at the beginning of the Activity, so how do I debug this?

You can disable InstantRun and see if the problem persists.

Android: Rare and Non-Reproducible ClassNotFoundException

I have a published app that gets reports about a ClassNotFoundExceptionfrom users that I went beyond my wits end trying to fix. I have not been able to reproduce this crash and similar instances of this error here on SO have either been cases of incorrect path to a dependency or a different package in the MainActivity than the manifest.
The issues with the wrong path to the dependencies are an Eclipse thing, while all the other errors could be easily fixed with Android Studio's "sync" and "clean project" (which I did to no avail).
I've triple checked all the package names and did not find any discrepancies.
Here is my manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.johan.fsc">
<uses-permission android:name = "android.permission.VIBRATE"/>
<uses-permission android:name="com.android.vending.BILLING" />
<application
android:allowBackup="true"
android:icon="#drawable/logo"
android:label="#string/app_name"
android:fullBackupContent="true">
<activity
android:name="com.johan.fsc.MainActivity"
android:screenOrientation="portrait"
android:label="#string/app_name"
android:theme="#style/splashscreenTheme"
android:hardwareAccelerated="false"
android:largeHeap="true">>
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name = "com.johan.fsc.SettingsActivity"
android:theme="#style/PreferencesTheme"/>
</application>
Here is the error report I always get from users:
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.johan.fsc/com.johan.fsc.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.johan.fsc.MainActivity" on path: DexPathList[[zip file "/data/app/com.johan.fsc-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2426)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2595)
at android.app.ActivityThread.access$800(ActivityThread.java:178)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1470)
at android.os.Handler.dispatchMessage(Handler.java:111)
at android.os.Looper.loop(Looper.java:194)
at android.app.ActivityThread.main(ActivityThread.java:5624)
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:959)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:754)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.johan.fsc.MainActivity" on path: DexPathList[[zip file "/data/app/com.johan.fsc-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
at android.app.Instrumentation.newActivity(Instrumentation.java:1071)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
... 10 more
Suppressed: java.io.IOException: Failed to open oat file from dex location '/data/app/com.johan.fsc-1/base.apk'
at dalvik.system.DexFile.openDexFileNative(Native Method)
at dalvik.system.DexFile.openDexFile(DexFile.java:295)
at dalvik.system.DexFile.<init>(DexFile.java:80)
at dalvik.system.DexFile.<init>(DexFile.java:59)
at dalvik.system.DexPathList.loadDexFile(DexPathList.java:262)
at dalvik.system.DexPathList.makeDexElements(DexPathList.java:231)
at dalvik.system.DexPathList.<init>(DexPathList.java:109)
at dalvik.system.BaseDexClassLoader.<init>(BaseDexClassLoader.java:48)
at dalvik.system.PathClassLoader.<init>(PathClassLoader.java:65)
at android.app.ApplicationLoaders.getClassLoader(ApplicationLoaders.java:57)
at android.app.LoadedApk.getClassLoader(LoadedApk.java:370)
at android.app.LoadedApk.makeApplication(LoadedApk.java:562)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4818)
at android.app.ActivityThread.access$1500(ActivityThread.java:178)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1531)
... 7 more
Caused by: java.io.IOException: Failed to open oat file from /data/app/com.johan.fsc-1/arm/base.odex (error Failed to open oat filename for reading: No such file or directory) (no dalvik_cache availible) and relocation failed.
... 22 more
Caused by: java.io.IOException:
... 22 more
Caused by: java.io.IOException: Failed to remove obsolete file from /data/dalvik-cache/arm/data#app#com.johan.fsc-1#base.apk#classes.dex when searching for dex file /data/app/com.johan.fsc-1/base.apk: Permission denied
... 22 more
Suppressed: java.lang.ClassNotFoundException: com.johan.fsc.MainActivity
at java.lang.Class.classForName(Native Method)
at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
... 13 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available/output.
It would seem that the culprit is java.io.IOException: Failed to remove obsolete file from /data/dalvik-cache/arm/data#app#com.johan.fsc-1#base.apk#classes.dex when searching for dex file /data/app/com.johan.fsc-1/base.apk: Permission denied, but I have not found why it's being invoked for some users and not the majority, and more importantly--how to fix it.

Possible Cause 1: There is a typo in the manifest in the line android:largeHeap="true">>. xml line ends with >>. This may be preventing the Intent-Filter from executing.
Possible Cause 2: My guess is that the phone is searching for a class <PackageName>.<PackageName>.<ClassName> instead of <PackageName>.<ClassName> . So definitely <PackageName>.<PackageName>.<ClassName> is not found and ClassNotFoundException would be the result. In android studio, in the manifest, by default activity name is written like this: android:name=".<ClassName>" instead of android:name="<PackageName>.<ClassName>" . You can give this a try.
Most phones may be checking whether packagename is added before the class name in the manifest. If it is added then they don't add it while searching of the class. While few phones must be adding the package name by default while searching for the class. Hence, they cannot find your class.

Certainly, you're naming your activity wrong. An activity CAN NOT consist the package's name in its name attribute.
Since you're already defining the package name here
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.johan.fsc">
You shouldn't mention that name here
<activity android:name="com.johan.fsc.MainActivity"
The only situation you should use package name along with a class's name is when the java class resides in a different package, as done in import statements.
Even if your activity is not present in the src folder and is instead present in a nested folder, android studio should handle the linking of manifest and the activity itself. Yet again, package name shouldn't be used there.

Class not found exception after adding library project

I have created a library project as .jar file and try to use it in another project. But I am getting Class not found exception while using it.I added all the activities from the library in my manifest file and its all permission. But still getting same error.
Here is my manifest file
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="#string/google_maps_key" />
<activity android:name=".Activities.MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="in.moovo.moovobroker.Activity.Mainactivity"/>
</application>
My error stack trace here :
java.lang.NoClassDefFoundError: Failed resolution of: Lin/moovo/moovobroker/R$layout;
at in.moovo.moovobroker.Activity.Mainactivity.onCreate(Mainactivity.java:85)
at android.app.Activity.performCreate(Activity.java:6072)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2315)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2424)
at android.app.ActivityThread.access$900(ActivityThread.java:155)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1323)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:139)
at android.app.ActivityThread.main(ActivityThread.java:5298)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:950)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:745)
Caused by: java.lang.ClassNotFoundException: Didn't find class "in.moovo.moovobroker.R$layout" on path: DexPathList[[zip file "/data/app/in.moovo.moovobrokerappmapview-2/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
at in.moovo.moovobroker.Activity.Mainactivity.onCreate(Mainactivity.java:85) 
at android.app.Activity.performCreate(Activity.java:6072) 
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2315) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2424) 
at android.app.ActivityThread.access$900(ActivityThread.java:155) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1323) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:139) 
at android.app.ActivityThread.main(ActivityThread.java:5298) 
at java.lang.reflect.Method.invoke(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:372) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:950) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:745) 
Suppressed: java.lang.ClassNotFoundException: in.moovo.moovobroker.R$layout
at java.lang.Class.classForName(Native Method)
at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
... 15 more
Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack available

This error is not for Activity. This is for in/moovo/moovobroker/R$layout which you used into in.moovo.moovobroker.Activity.Mainactivity.
The way you are using is not correct way. When you decide to use jar file, the classes which are into jar, should not have dependency on any external resources.
Correct way is to use aar file. Read how to Create aar file in Android Studio

jar files contain only code! No activities can be found in your jar file. If you wish to use the activity resource files, you should use aar file instead.
Specifically: the 'aar' bundle is the binary distribution of an Android Library Project.
The file extension is .aar, and the maven artifact type should be aar as well, but the file itself a simple zip file with the following entries:
/AndroidManifest.xml (mandatory)
/classes.jar (mandatory)
/res/ (mandatory)
/R.txt (mandatory)
/assets/ (optional)
/libs/*.jar (optional)
/jni/<abi>/*.so (optional)
/proguard.txt (optional)
/lint.jar (optional)
These entries are directly at the root of the zip file.
See also this post for details.

java.lang.ClassNotFoundException when install app from APK [duplicate]

This question already has answers here:
Android ClassNotFoundException: Didn't find class on path
(37 answers)
Closed 8 years ago.
The error I describe below, occurs when:
Install the app on a device directly from the APK.
Download the app by Play Store
The error don´t occurs when:
Install apk through Eclipse pressing the 'run' button
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{my.package/my.package.MainActivity}:
java.lang.ClassNotFoundException: my.package.MainActivity
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1998)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2099)
at android.app.ActivityThread.access$600(ActivityThread.java:138)
at android.app.ActivityThread$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:4929)
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:798)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:565)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassNotFoundException: my.package.MainActivity
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:1056)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1989)
... 11 more
To export the APk I do as always, from "Use the Export Wizard to export and sign an APK"
Any idea because it occurs from the APK but not directly from eclipse?
The above error is generated by me. But reports of users are somewhat different:
User1:
java.lang.RuntimeException: Unable to instantiate activity
ComponentInfo{my.package/my.package.MainActivity}:
java.lang.ClassNotFoundException: Didn't find class
"my.package.MainActivity" on path: DexPathList[dexElements=[zip file
"/data/app/my.package-1.apk"],nativeLibraryDirectories=[/data/app-lib/my.package-1,
/vendor/lib, /system/lib]]
User2:
java.lang.RuntimeException: Unable to instantiate activity
ComponentInfo{my.package/my.package.MainActivity}:
java.lang.ClassNotFoundException: Didn't find class
"my.package.MainActivity" on path: DexPathList[[zip file
"/data/app/my.package-1.apk"],nativeLibraryDirectories=[/data/app-lib/my.package-1,
/vendor/lib, /system/lib]]
Manifest:
<?xml version="1.0" encoding="utf-8"?> <manifest
xmlns:android="http://schemas.android.com/apk/res/android"
package="my.package"
android:versionCode="12"
android:versionName="2.3" >
<uses-sdk
android:minSdkVersion="9"
android:targetSdkVersion="21" />
<application
android:allowBackup="true"
android:icon="#drawable/motion"
android:label="#string/app_name"
android:largeHeap="true"
android:theme="#style/Theme.AppCompat.Light" >
<activity
android:name="my.package.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="my.package.AlarmsListActivity"
android:theme="#style/dialogTheme"/>
<activity android:name="my.package.ImagenesActivity"/>
<activity android:name="my.package.EndActivity" />
</application>
</manifest>
I use the following libraries in MainActivity

This is your error:
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{my.package/my.package.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "my.package.MainActivity" on path: DexPathList[dexElements=[zip file "/data/app/my.package-1.apk"],nativeLibraryDirectories=[/data/app-lib/my.package-1, /vendor/lib, /system/lib]]
Solution:
You have added library project as a reference to your project and also may be you have added jar files for ChartView and support-v7 in your libs folder and also as a Add External Jars. So you have to enable both checkboxes for android-support-v7.jar file and for chartview jar file in order and export menu.
The path for it is,
Project - Right Click - Properties - Java Build Path - Order and Export Menu.
Finally you need to clean and run your project.