Android: NoClassDefFoundError only on release build

Question

I'm on Android Studio and trying to build my project on release mode.
Everything is OK in debug mode however below errors occur in release mode...

08-26 17:59:05.599  31696-31931/? W/System.err﹕ java.lang.NoClassDefFoundError: a.a.b.l
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at java.lang.Class.classForName(Native Method)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at java.lang.Class.forName(Class.java:308)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at java.lang.Class.forName(Class.java:272)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at com.a.a.a.a(Unknown Source)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at com.a.a.a.a(Unknown Source)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at com.a.a.e.b(Unknown Source)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at com.a.a.e.a(Unknown Source)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at com.a.e.a.uncaughtException(Unknown Source)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:693)
08-26 17:59:05.599  31696-31931/? W/System.err﹕ at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:690)
08-26 17:59:05.600  31696-31931/? E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #2
    Process: com.soonoo.mobilecampus, PID: 31696
    java.lang.RuntimeException: An error occured while executing doInBackground()
            at android.os.AsyncTask$3.done(AsyncTask.java:300)
            at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
            at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
            at java.util.concurrent.FutureTask.run(FutureTask.java:242)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:818)
     Caused by: java.lang.ExceptionInInitializerError
            at a.a.b.l.a(Unknown Source)
            at a.a.b.m.<clinit>(Unknown Source)
            at a.a.b.f.<init>(Unknown Source)
            at a.a.b.e.<init>(Unknown Source)
            at a.a.c.di.b(Unknown Source)
            at a.a.c.di.a(Unknown Source)
            at a.a.c.b.a(Unknown Source)
            at a.a.c.ae.b(Unknown Source)
            at a.a.a.a(Unknown Source)
            at com.soonoo.mobilecampus.mainlist.h.a(Unknown Source)
            at com.soonoo.mobilecampus.mainlist.h.doInBackground(Unknown Source)
            at android.os.AsyncTask$2.call(AsyncTask.java:288)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:818)
     Caused by: java.lang.NullPointerException: in == null
            at java.util.Properties.load(Properties.java:246)
            at a.a.b.l.d(Unknown Source)
            at a.a.b.l.<clinit>(Unknown Source)
            at a.a.b.l.a(Unknown Source)
            at a.a.b.m.<clinit>(Unknown Source)
            at a.a.b.f.<init>(Unknown Source)
            at a.a.b.e.<init>(Unknown Source)
            at a.a.c.di.b(Unknown Source)
            at a.a.c.di.a(Unknown Source)
            at a.a.c.b.a(Unknown Source)
            at a.a.c.ae.b(Unknown Source)
            at a.a.a.a(Unknown Source)
            at com.soonoo.mobilecampus.mainlist.h.a(Unknown Source)
            at com.soonoo.mobilecampus.mainlist.h.doInBackground(Unknown Source)
            at android.os.AsyncTask$2.call(AsyncTask.java:288)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
            at java.lang.Thread.run(Thread.java:818)

The problem is that exception messages do not display the name of classes, methods that occurs error.
All third party libraries I used in my project are specified in build.gradle.
How can I fix this?

The problem is possible this buildTypes { release { minifyEnabled false proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro' signingConfig signingConfigs.release } } — Smashing, Aug 26 '15 at 09:13
If you set minifyEnabled to false in your build.gradle it should work. — Smashing, Aug 26 '15 at 09:14
Some of the libraries you use require you to declare proguard rules for it's classes, once you do that you'll be fine. Also proguard will obscure your classes too, if you don't want a particular class to be obscured, set rules for that. — Udit Mukherjee, Aug 26 '15 at 09:14

score 8 · Accepted Answer · answered Aug 26 '15 at 09:24

8

The problem is basically the following:

buildTypes {
        release {
            **minifyEnabled false**
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }

If you set minifyEnabled to false, it should fix your problem. If you want to use the minify feature then you can add progaurd rules to your build.gradle. For instance for the Butterknife library you have to add the following:

-keep class butterknife.** { *; }
-dontwarn butterknife.internal.**
-keep class **$$ViewBinder { *; }

-keepclasseswithmembernames class * {
    @butterknife.* <fields>;
}

-keepclasseswithmembernames class * {
    @butterknife.* <methods>;
}

Glad I could help

answered Aug 26 '15 at 09:24

Smashing

1,640
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16

1

How can I know what libraries should be added into proguard? – soonoo Aug 26 '15 at 09:26
Usually on the libraries website it will tell you if it needs to be added. We don't use it for now so i'm not entirely sure. If you found the answer usefull then please accept it as the correct one. Have a good day man!. – Smashing Aug 26 '15 at 09:28
I get this error despite setting minifyEnabled false :( – wick.ed Jul 19 '17 at 19:46

Rahul Kahale · Answer 2 · 2020-11-23T17:29:23.760

In my case it was working for all database tables, except one which was specifically passed as argument inside UI Navigation So, if you are using UI Navigation with serializable argument type as one of the roomdb table, make sure you are not mentioning the class name of it in the XML file (as that will be changed in release DEX/minification process.)

XML file: Navigation.xml containing

<navigation>
        <fragment> 
            <argument android:name="questionObj" app:argType="roomdb.db.question" /> // removed for Fixing
            <action
            android:id="@+id/action_q1_to_q2">
        </fragment> 
    </navigation>

<argument ..... /> line was removed as a fix.

bundle!!.getSerializable("questionObj") as Question?

Should be used for passing

Errors were helpful & accurate

W/System.err: Caused by: java.lang.RuntimeException: Exception inflating navigation/navigation line 83
W/System.err: Caused by: java.lang.RuntimeException: java.lang.ClassNotFoundException: database.db.Question
W/System.err: Caused by: java.lang.ClassNotFoundException: database.db.Question
W/System.err: Caused by: java.lang.ClassNotFoundException: Didn't find class "database.db.Question" on path: DexPathList[[zip file "/data/app/appname-zu2-cBYoT7e345HeXbjQsgtpA==/base.apk"],nativeLibraryDirectories=[/data/app/appname-zu2-cBYoT7e345HeXbjQsgtpA==/lib/arm64, /system/lib64, /product/lib64]]
I/PackageManager.DexOptimizer: Running dexopt (dexoptNeeded=-3) on: /data/app/appname-zu2-cBYoT7e345HeXbjQsgtpA==/base.apk pkg=appname isa=arm64 dexoptFlags=boot_complete,profile_guided,enable_hidden_api_checks targetFilter=speed-prof

Android: NoClassDefFoundError only on release build

2 Answers2

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