Develop Reference

Missing class: com.google.android.aidl.BaseProxy

Occasionally after generating the Signed APK, the following warning would appear
Missing class: com.google.android.aidl.BaseProxy
Missing Class: com.google.android.aidl.BaseStub
However, the APK would be successfully generated. Only when released the warning would be detrimental to the app.
Fatal Exception: java.lang.NoClassDefFoundError
Failed resolution of: Lcom/google/android/aidl/BaseStub
What gradle dependancy is required so this class is found and resolved?
Here are links to my gradle files (shared on google drive):
build.gradle (module: app)
build.gradle (project)
Thanks.

Try to update your proguard rules with the following:
-keepclassmembers class com.google.android.aidl.** { *; }
EDIT: (from proguard documentation)
-keep: Specifies classes and class members (fields and methods) to be preserved as entry points to your code.
-keepclassmembers: Specifies class members (only) to be preserved, if their classes are preserved as well.
If you specify a class, without class members, ProGuard only preserves the class and its parameterless constructor as entry points. It may still remove, optimize, or obfuscate its other class members.
If you specify a method, ProGuard only preserves the method as an entry point. Its code may still be optimized and adapted.
So if you're not sure which option you need, you should probably simply use -keep. It will make sure the specified classes and class members are not removed in the shrinking step, and not renamed in the obfuscation step.
(below -keep includes all classes and class members from aidl)
-keep class com.google.android.aidl.** { *; }
In your case you are missing BaseProxy and BaseStub classes. You can specify only these classes in your -keep and -keepclassmembers and test which method is suitable for you with best code obfuscation for your release build.
(below -keep includes only BaseProxy and BaseStub)
-keep class com.google.android.aidl.BaseProxy { *; }
-keep class com.google.android.aidl.BaseStub { *; }
My suggestion is to specify the class names you don't want to remove and utilize the code obfuscation to reduce your app size.

The symptoms of your issue (only happens in release build means proguard is removing the class) leads me to suggest :
if the class missing is one of yours add this annotation to the that class
#Keep class TheClass { ... }
if the class giving you pain is in the third party lib (mostly you add lib via gradle file in your project ) then normally in the library readme file (from their website like Github repo readme etc ) there is a proguard rules note that you need to add something like :
# Parceler library
-keep interface org.parceler.Parcel
-keep #org.parceler.Parcel class * { *; }
-keep class **$$Parcelable { *; }

Native crashes on some devices with ProGuard

EDIT: For future devs who may be suffering from the same issues, I'm afraid I can't be of much use. The problem apparently solved itself during future versions of the app, but I have been unable to ascertain the cause.
I've been testing an application through the Google Play closed beta testing system, using my friends as beta testers. After pushing an update where the .apk was obfuscated using ProGuard, two testers started reporting crashes. The crashes are unpredictable and sporadic, and they have been unable to ascertain any reason or pattern for them. To make things worse, the crash reports I'm getting in the Dev Console contain no information at all, simply stating "Native crash at (no location available)", no stack trace, not even any device information.
I do know the device information through just asking the testers in question, and both devices are Sony phones, an Xperia Z3 and an Xperia Z3 Compact. However, I also have a Z3 Compact available for testing and have been unable to reproduce the crash while running the same obfuscated apk. We are running the same OS version as well.
I have sent one of the testers and unobfuscated apk, and he was unable to reproduce the crash running that version. This, and the fact that the crash first occurred after a patch that introduced ProGuard obfuscation, leads me to believe that to be the cause.
At first, I ran ProGuard using only the default configuration file from the SDK:
# This is a configuration file for ProGuard.
# LINK REMOVED
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-verbose
# Optimization is turned off by default. Dex does not like code run
# through the ProGuard optimize and preverify steps (and performs some
# of these optimizations on its own).
-dontoptimize
-dontpreverify
# Note that if you want to enable optimization, you cannot just
# include optimization flags in your own project configuration file;
# instead you will need to point to the
# "proguard-android-optimize.txt" file instead of this one from your
# project.properties file.
-keepattributes *Annotation*
-keep public class com.google.vending.licensing.ILicensingService
-keep public class com.android.vending.licensing.ILicensingService
# For native methods, see LINK REMOVED
-keepclasseswithmembernames class * {
native <methods>;
}
# keep setters in Views so that animations can still work.
# see http://proguard.sourceforge.net/manual/examples.html#beans
-keepclassmembers public class * extends android.view.View {
void set*(***);
*** get*();
}
# We want to keep methods in Activity that could be used in the XML attribute onClick
-keepclassmembers class * extends android.app.Activity {
public void *(android.view.View);
}
# For enumeration classes, see http://proguard.sourceforge.net/manual/examples.html#enumerations
-keepclassmembers enum * {
public static **[] values();
public static ** valueOf(java.lang.String);
}
-keepclassmembers class * implements android.os.Parcelable {
public static final android.os.Parcelable$Creator CREATOR;
}
-keepclassmembers class **.R$* {
public static <fields>;
}
# The support library contains references to newer platform versions.
# Don't warn about those in case this app is linking against an older
# platform version. We know about them, and they are safe.
-dontwarn android.support.**
I have since added the following lines to proguard-project.txt, which is also included in the proguard configuration variable for the project:
-keep class * extends java.util.ListResourceBundle {
protected java.lang.Object[][] getContents();
}
# Keep SafeParcelable value, needed for reflection. This is required to support backwards
# compatibility of some classes.
-keep public class com.google.android.gms.common.internal.safeparcel.SafeParcelable {
public static final *** NULL;
}
# Keep the names of classes/members we need for client functionality.
-keepnames #com.google.android.gms.common.annotation.KeepName class *
-keepclassmembernames class * {
#com.google.android.gms.common.annotation.KeepName *;
}
# Needed for Parcelable/SafeParcelable Creators to not get stripped
-keepnames class * implements android.os.Parcelable {
public static final ** CREATOR;
}
# Needed when building against the Marshmallow SDK
-dontwarn org.apache.http.**
# Needed when building against pre-Marshmallow SDK.
-dontwarn android.security.NetworkSecurityPolicy
-keep public class * extends android.app.Activity
-keep public class * extends android.app.Application
-keep public class * extends android.app.Service
-keep public class * extends android.content.BroadcastReceiver
-keep public class * extends android.content.ContentProvider
-libraryjars D:/Docs/Android/spaceprog/spaceprogr/libs/android-support-v4.jar
-keep class com.viewpagerindicator.** { *; }
-keep class com.google.android.gms.** { *; }
-keep class com.google.example.games.basegameutils.** { *; }
-printmapping out.map
-renamesourcefileattribute SourceFile
-keepattributes SourceFile,LineNumberTable
The upper part (with comments) of these additions comes directly from the README of the Google Play Services as a recommendation to be added whenever using the library. The rest I added myself while trying to research and debug the problem.
If anyone notices any omissions or other signs of trouble in my ProGuard configuration I'd be happy to know. I'd also be greatful for any suggestions on how to further debug the problem. Keep in mind that full module testing where only one module is obfuscated at a time is impossible in this case, because I do not have a device that can reproduce the issue and I cannot ask volunteer testers to install 30+ different versions of the .apk and play until it either crashes or until they are confident it will not.

proguard warning: the configuration keeps the entry point....but not the descriptor class

I've configured:
-keep ,allowoptimization,allowobfuscation,allowshrinking public class org.jf.dexlib2.dexbacked.** {
*;
}
but still getting the warning:
Note: the configuration keeps the entry point 'com.trusteer.trf.dex_parser { int get_strings_count(org.jf.dexlib2.dexbacked.DexBackedDexFile); }', but not the descriptor class 'org.jf.dexlib2.dexbacked.DexBackedDexFile'
I am using proguard version 4.7 (in Android SDK)
What should I do?

You have told Proguard to keep a certain method void foo(Bar bar); but to obfuscate the descriptor class Bar.
This is only a problem if you are going to invoke the method from an external source as the signature will be changed by the obfuscation (if you use Proguard to obfuscate a library and then use that library in another app).
So have the following choices:
Configure Proguard to also keep Bar.
Use the -dontnote directive to tell Proguard not to print notes like this.

Note: the configuration keeps the entry point '...', but not the descriptor class '...'
Your configuration contains a -keep option to preserve the given method (or field), but no -keep option for the given class that is an argument type or return type in the method's descriptor. You may then want to keep the class too. Otherwise, ProGuard will obfuscate its name, thus changing the method's signature. The method might then become unfindable as an entry point, e.g. if it is part of a public API. You can automatically keep such descriptor classes with the -keep option modifier includedescriptorclasses (-keep,includedescriptorclasses ...). You can switch off these notes by specifying the -dontnote option.

Add this line in your 'proguard-rules.pro' file to fix this problem .
-ignorewarnings

From the docuemnts:
allowshrinking Specifies that the entry points specified in the -keep
option may be shrunk, even if they have to be preserved otherwise.
That is, the entry points may be removed in the shrinking step, but if
they are necessary after all, they may not be optimized or obfuscated
So it appears that you need to remove the allowshrinking modifier.

In my case this problem appears when I add to build.gradle
minifyEnable true
Official instructions: https://flutter.dev/docs/deployment/android
Bug https://github.com/flutter/flutter/issues/19250
Sample proguard-rules.pro file:
#Flutter Wrapper
-ignorewarnings
-keep class io.flutter.app.** { *; }
-keep class io.flutter.plugin.** { *; }
-keep class io.flutter.util.** { *; }
-keep class io.flutter.view.** { *; }
-keep class io.flutter.** { *; }
-keep class io.flutter.plugins.** { *; }

I did some digging in the docs. You have not supplied your whole configuration file, but I'm guessing that that com.trusteer.trf.dex_parser is set to both keep and not to obfuscate.
This means that there is a refrence from com.trusteer.trf.dex_parser to a class called org.jf.dexlib2.dexbacked.DexBackedDexFile that was either shrunk or obfuscated. This means that the link is now broken - dex_parser can't import DexBackedDexFile.
So either disable shrinking and obfuscation for DexBackedDexFile, or allow optimization and obfuscation on dex_parser.

Proguard and Netty 5 on Android

I've seen a couple questions regarding this issue, but they are for older versions of Netty.
I have tried their answers, switching org.jboss.netty out with io.netty, but the same error occurs.
I'm trying to compile an Android app that uses Netty 5.0.0Alpha2 (build #16) with Proguard enabled.
Without Proguard, the app runs fine.
As soon as I enable Proguard, I get this exception when it tries to use Netty:
java.lang.IllegalStateException: unknown type parameter 'I': class io.netty.channel.SimpleChannelInboundHandler
at io.netty.util.internal.TypeParameterMatcher.find0(Unknown Source)
at io.netty.util.internal.TypeParameterMatcher.find(Unknown Source)
at io.netty.channel.SimpleChannelInboundHandler.<init>(Unknown Source)
at io.netty.channel.SimpleChannelInboundHandler.<init>(Unknown Source)
...
This is my Proguard config:
# billing
-keep class com.android.vending.billing.**
# butterknife
-dontwarn butterknife.internal.**
-keep class **$$ViewInjector {
*;
}
-keepnames class * {
#butterknife.InjectView *;
}
# admob
-keep public class com.google.android.gms.ads.** {
public *;
}
-keep public class com.google.ads.** {
public *;
}
# logging
-assumenosideeffects class android.util.Log
# netty (partial)
-dontwarn io.netty.**
-dontwarn sun.**
I have tested it without the -dontwarn options to see if the warnings would point me in the right direction, but it's all missing optional dependencies like slf4j and Tomcat.
I have also tried excluding all the Netty classes like so:
-keep class io.netty.** {
*;
}
...but that does not appear to fix it either.

I have fixed this issue with some carefully* applied Proguard rules after reading through parts of the rather huge Netty sources:
-keepattributes Signature,InnerClasses
-keepclasseswithmembers class io.netty.** {
*;
}
-keepnames class io.netty.** {
*;
}
My original exception was caused by the type variables being removed from the bytecode, which Netty uses via reflection. Signature in -keepattributes keeps this information.
You get a slightly different exception if you only do Signature on -keepattributes - adding InnerClasses fixes this one by bringing back even more information in the class files.
Later, I got java.lang.NoSuchFieldException: ctl; that's what -keepnames is for. This way, the field is still called ctl like Netty expects.
Finally, some members (like ctl, seen earlier) were being removed by Proguard because Netty only uses them via reflection. The final rule, -keepclasseswithmembers, makes sure Proguard doesn't remove them.
If you take this approach, I strongly recommend you use only the Netty jars you need, instead of the -all jar. Switching from -all to just the required Netty jars brought my method count way down after I had gone past the 65k limit. Reducing your jars requires bit of trial-and-error though as the separation is unclear and there's not really any resources saying what's what.
* not carefully at all, I just slapped rules into the file and removed them if they did nothing. There's probably a better way to do this that doesn't keep this information in the entire program, but instead just Netty.

Una's answer keep too many classes, which makes my app 1MB larger than usual. So I use the rules below:
# netty
-keepclassmembernames class io.netty.buffer.AbstractByteBufAllocator {
*;
}
-keepclassmembernames class io.netty.buffer.AdvancedLeakAwareByteBuf {
*;
}
-keep public class io.netty.util.ReferenceCountUtil {
*;
}

ConnectivityManager ClassCastException with Google Analytics v4 and ProGuard

I'm having troubles compiling an app that uses ProGuard and Google Analytics v4. A single other thread that seems to be similar is here, except there aren't very many details.
I've tried the following to no avail:
Doing keep com.google.** { *; }
Doing a -keep android.support.** { *; } package. This error continues to crop up with every other bit of obfuscated code, as if joining the newly obfuscated code with the pre-obfuscated Google Analytics code always causes errors.
Using -keepattributes Signature in case there's an issue with generics.
Using an obfuscated dictionary of four-letter words (such as rNqp, sSlq) in case something to do with Android dexing causes the pre-obfuscated Google Analytics classes to conflict with the obfuscated project files.
Here is the exception:
11-08 22:45:01.644 2206-2226/com.example.helloworld E/GAV3﹕ Thread[GAThread,5,main]: Error on GAThread: java.lang.ClassCastException: android.net.ConnectivityManager cannot be cast to android.support.v4.d.a
at com.google.a.a.a.at.a(Unknown Source)
at com.google.a.a.a.am.a(Unknown Source)
at com.google.a.a.a.s.h(Unknown Source)
at com.google.a.a.a.s.g(Unknown Source)
at com.google.a.a.a.s.a(Unknown Source)
at com.google.a.a.a.u.run(Unknown Source)
at com.google.a.a.a.ab.run(Unknown Source)
11-08 22:45:01.644 2206-2226/com.example.helloworld E/GAV3﹕ Thread[GAThread,5,main]: Google Analytics is shutting down.
Proguard configuration file (99.9% vanilla):
# This is a configuration file for ProGuard.
# http://proguard.sourceforge.net/index.html#manual/usage.html
# Optimizations: If you don't want to optimize, use the
# proguard-android.txt configuration file instead of this one, which
# turns off the optimization flags. Adding optimization introduces
# certain risks, since for example not all optimizations performed by
# ProGuard works on all versions of Dalvik. The following flags turn
# off various optimizations known to have issues, but the list may not
# be complete or up to date. (The "arithmetic" optimization can be
# used if you are only targeting Android 2.0 or later.) Make sure you
# test thoroughly if you go this route.
#-optimizations !code/simplification/cast,!field/*,!class/merging/*
#-optimizationpasses 5
#-allowaccessmodification
#-dontpreverify
# The remainder of this file is identical to the non-optimized version
# of the Proguard configuration file (except that the other file has
# flags to turn off optimization).
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-verbose
-keepattributes *Annotation*
-keep public class com.google.vending.licensing.ILicensingService
-keep public class com.android.vending.licensing.ILicensingService
# For native methods, see http://proguard.sourceforge.net/manual/examples.html#native
-keepclasseswithmembernames class * {
native <methods>;
}
# keep setters in Views so that animations can still work.
# see http://proguard.sourceforge.net/manual/examples.html#beans
-keepclassmembers public class * extends android.view.View {
void set*(***);
*** get*();
}
# We want to keep methods in Activity that could be used in the XML attribute onClick
-keepclassmembers class * extends android.app.Activity {
public void *(android.view.View);
}
# For enumeration classes, see http://proguard.sourceforge.net/manual/examples.html#enumerations
-keepclassmembers enum * {
public static **[] values();
public static ** valueOf(java.lang.String);
}
-keep class * implements android.os.Parcelable {
public static final android.os.Parcelable$Creator *;
}
-keepclassmembers class **.R$* {
public static <fields>;
}
# The support library contains references to newer platform versions.
# Don't warn about those in case this app is linking against an older
# platform version. We know about them, and they are safe.
-dontwarn android.support.**
-keepattributes Signature

It seems like you're using a copy of proguard-android-optimize.txt (a more common approach is to refer to the original, maintained file in the Android SDK). You can try disabling optimization:
-dontoptimize
If this indeed avoids the problem, you can report the issue in ProGuard's bug tracker or to me directly.
Make sure that you are using the latest version of ProGuard (version 5.1 at this time of writing) and the latest version of the GMS library.
(I am the developer of ProGuard)

I've found the solution. It just involves not obfuscating the ConnectivityManager. I've used:
-keep android.net.** { *; }
which is working fine.