Prevent class member name obfuscation by ProGuard

I have my class ClassMultiPoint with subclasses.

public class ClassMultiPoints
 {
   public String message;
   public List<ClassPoints> data;

   public class ClassPoints
    {
      public String id;
      public List<ClassPoint> points;
      public class ClassPoint
       {
         public String speed;
         public String bearing;
       }
    }
 }

I will get value of object oPoints from parse GSON:

oPoints = gson.fromJson( jsonString, ClassMultiPoints.class);

I try use oPoints.message.

When I run my application without proguard app run success. When I run my app with proguard my app crash.

I think problem is: proguard rename attribute 'oPoints.message' of my class to short 'a'.

I try keep the names of the methods and attributes is constant, but proguard rename its:

proguard.cfg:

-injars      bin/classes
-injars      libs
-outjars     bin/classes-processed.jar
-dontpreverify
-repackageclasses ''
-allowaccessmodification
-optimizations !code/simplification/arithmetic
-keepattributes *Annotation*
-dontskipnonpubliclibraryclasses
-optimizationpasses 5
-printmapping map.txt
-flattenpackagehierarchy

-keep public class * extends android.app.Activity
-keep public class * extends android.app.Application
-keep public class * extends android.app.MapActivity
-keep public class * extends android.app.Service
-keep public class * extends android.content.BroadcastReceiver
-keep public class * extends android.content.ContentProvider

-libraryjars  libs/commons-io-2.2.jar
-libraryjars  libs/ftp4j-1.7.1.jar
-libraryjars  libs/gson-2.2.2.jar

-keep public class org.apache.commons.io.**
-keep public class it.sauronsoftware.ftp4j.**
-keep public class com.google.gson.**

-keep public class com.mypackagename.ActivityMonitor$*

-keep public class * extends android.view.View {
    public <init>(android.content.Context);
    public <init>(android.content.Context, android.util.AttributeSet);
    public <init>(android.content.Context, android.util.AttributeSet, int);
    public void set*(...);
}

-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet);
}

-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet, int);
}

-keepclassmembers class * extends android.content.Context {
   public void *(android.view.View);
   public void *(android.view.MenuItem);
}

-keepclassmembers class * implements android.os.Parcelable {
    static android.os.Parcelable$Creator CREATOR;
}

-keepclassmembers class **.R$* {
    public static <fields>;
}

What is right way to keep names of the methods and attributes of the my one (static) class?

If you dont want your class members to be obfuscated then use SerializedName annotation provided by Gson. For example:

public class ClassMultiPoints
{
   @SerializedName("message")
   public String message;
   @SerializedName("data")
   public List<ClassPoints> data;

   ...

}

Moreover, make sure you do add proper proguard configuration for Gson library too. For example:

##---------------Begin: proguard configuration for Gson ----------
# Gson uses generic type information stored in a class file when working with
#fields. Proguard removes such information by default, so configure it to keep
#all of it.
-keepattributes Signature

# For using GSON @Expose annotation
-keepattributes *Annotation*

# Gson specific classes
-keep class sun.misc.Unsafe { *; }
#-keep class com.google.gson.stream.** { *; }

# Application classes that will be serialized/deserialized over Gson
-keep class com.google.gson.examples.android.model.** { *; }

##---------------End: proguard configuration for Gson ----------

For more info read this.

Thanks Waqas!

I find solution for my case:

-optimizationpasses 5
-dump class_files.txt
-printseeds seeds.txt
-printusage unused.txt
-printmapping mapping.txt
-optimizations !code/simplification/arithmetic,!field/*,!class/merging*/
-allowaccessmodification
-repackageclasses ''

-keep public class * extends android.app.Activity
-keep public class * extends android.app.Application
-keep public class * extends android.app.MapActivity
-keep public class * extends android.app.Service
-keep public class * extends android.content.BroadcastReceiver
-keep public class * extends android.content.ContentProvider

-libraryjars  libs/commons-io-2.2.jar
-libraryjars  libs/gson-2.2.2.jar
-keep public class org.apache.commons.io.**
-keep public class com.google.gson.**
-keep public class com.google.gson.** {public private protected *;}

##---------------Begin: proguard configuration for Gson ----------
-keepattributes *Annotation*,Signature
-keep class com.mypackage.ActivityMonitor.ClassMultiPoints.** { *; }
-keep public class com.mypackage.ActivityMonitor$ClassMultiPoints     { public protected *; }
-keep public class com.mypackage.ActivityMonitor$ClassMultiPoints$ClassPoints { public protected *; }
-keep public class com.mypackage.ActivityMonitor$ClassMultiPoints$ClassPoints$ClassPoint { public protected *; }
# To support Enum type of class members
-keepclassmembers enum * { *; } 
##---------------End: proguard configuration for Gson ----------

Also I don't use @SerializedName("message") in my class, aboved config work fine without serialization.

I also found I need to -keepclassmembers when using Dexguard's optimise option. Without this several of my model objects failed to deserialise

##---------------Begin: proguard configuration for Gson  ----------
# Gson uses generic type information stored in a class file when working with fields. Proguard
# removes such information by default, so configure it to keep all of it.
-keepattributes Signature

# For using GSON @Expose annotation
-keepattributes *Annotation*

# Application classes that will be serialized/deserialized over Gson, keepclassmembers
-keep class com.myapp.model.** { *; }
-keepclassmembers class com.myapp.model.** { *; }

If you use the @Expose annotation like I do, you can tell ProGuard to keep any field annotated with it:

# keep anything annotated with @Expose
-keepclassmembers public class * {
    @com.google.gson.annotations.Expose *;
}
# Also keep classes that @Expose everything
-keep @com.google.gson.annotations.Expose public class *

To exclude your class from obfuscation, Keep the attributes of InnerClasses, keep your class and keep the class members of the class eg.

-keepattributes InnerClasses
 -keep class com.yourproject.YourClass**
 -keepclassmembers class com.yourproject.YourClass** {
    *;
 }

For more information http://proguard.sourceforge.net/manual/examples.html

There is a built-in @Keep annotation that you use, please refer this link

Proguard 6.1 cannot handle interfaces with generics in a library. See the bug report here: https://sourceforge.net/p/proguard/bugs/765/

You can skip obfuscation in all Request type classes

open class Request
data class Example(val name: String) : Request()

proguard-rules.pro

-keepclassmembers class * extends <your-package-name>.util.ws.Request { *; }

GL

This thread has amazing answers already, however do not forget to add

-keep public class * extends java.lang.Exception

otherwise, all the crashes will be obfuscated when you see them on firebase.

See official docs here : https://firebase.google.com/docs/crashlytics/get-deobfuscated-reports?platform=android