IMPORTANT

these tools were removed and are no longer supported in dex2jar version 2.0 and later.

if you know of alternative tools for renaming identifiers in Java bytecode using a map file, please add them here.

Introduction

dex-tool-0.0.9.8 add support to DeObfuscate a jar

Details

The Problem

for a Obfuscated jar like this

package a;
public class a
{
  static String a = "Hello";
  static void a() {
    System.out.println(a);
  }
  public static void main(String[] args) {
    a();
  }
}

all package,class,field,method names are 'a', which is difficult to read.

DeObfuscate It

run the following command

#generate a 'suggest' config for rename
d2j-init-deobf -f -o init.txt a.jar

we got a init.txt

p a=pa
c a/a=C000_a
m a/a.a()=Ma
m a/a.a=Fa

which means

#rename package a to pa
p a=pa
#rename class a to C000_a
c a/a=C000_a
#rename method a to Ma
m a/a.a()=Ma
#rename field a to Fa
m a/a.a=Fa

modify init.txt to

#rename package a to hello
p a=hello
#rename class a to World
c a/a=World
#rename method a to say
m a/a.a()=say
#rename field a to message
m a/a.a=message

and run

d2j-jar-remap -f -c init.txt -o a-deobf.jar a.jar

now we get the comfortable source

package hello;

import java.io.PrintStream;

public class World
{
  static String message = "Hello";

  static void say() {
    System.out.println(message);
  }

  public static void main(String[] args) {
    say();
  }
}

or run the program with

java -cp a-deobf.jar hello.World