How to obfuscate everything but public method names and attributes with proguard?

Question

I'm building an android framework and I need to obfuscate and shrink the jar to ship it to users.

I'm using the proguard tool included in the android SDK and I have the following requirements for the output jar:

• keep all the classes included in the input jar, but obfuscate them.
• don't obfuscate the class names of the classes called in the `AndroidManifest.xml
• don't obfuscate the class name and public method names/attributes for the class that is used has an interface for the user, however do it for their contents.

To do so, I use the following configuration :

-optimizationpasses 5
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-dontpreverify
-verbose

-keep, allowobfuscation class com.company.*
-keepclassmembers, allowobfuscation class * {
    *;
}


-keepnames class com.company.MyClass { *; }
-keepclassmembernames class com.company.MyClass {
    public <methods>;
    public <fields>;
    #!private *; also tried this but it didn't work
}

However my private classes names and attributes still have the same name even though the content is obfuscated. Did I miss something in my wildcards?

Answer 1

After playing a bit, I found the following to be working

-optimizationpasses 5
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-dontpreverify
-verbose

-keep, allowobfuscation class com.company.*
-keepclassmembers, allowobfuscation class * {
    *;
}

-keepnames class com.company.MyClass
-keepclassmembernames class com.company.MyClass {
    public <methods>;
    public <fields>;
    #!private *; also tried this but it didn't work
}

The error in your configuration is the presence of { *; } at the end of the -keepnames option.

I used the following class:

package com.company;

public class MyClass {
  public static void main(String[] args) {
    int longVariableName = publicStaticMethod();
    String abcxyz = privateStaticMethod("abc", "xyz");
    System.out.println("longVariableName: " + longVariableName);
    System.out.println("abcxyz: " + abcxyz);
  }

  public static int publicStaticMethod() {
    return 9000;
  }

  private static String privateStaticMethod(String first, String second) {
    return first + second;
  }
}

and the decompiled resulting class was this:

package com.company;

import java.io.PrintStream;

public class MyClass {
  public static void main(String[] paramArrayOfString) {
    paramArrayOfString = publicStaticMethod();
    String str = a("abc", "xyz");
    System.out.println("longVariableName: " + paramArrayOfString);
    System.out.println("abcxyz: " + str);
  }
  
  public static int publicStaticMethod() {
    return 9000;
  }
  
  private static String a(String paramString1, String paramString2) {
    return paramString1 + paramString2;
  }
}