Android 代码混淆

1.为什么要混淆

作为Android应用开发者，不得不面对一个尴尬的局面，就是自己辛辛苦苦开发的应用可以被别人很轻易的就反编译出来。

Google似乎也发现了这个问题，从SDK2.3开始我们可以看到在android-sdk-windows\tools\下面多了一个proguard文件夹。

proguard是一个java代码混淆的工具，通过proguard，别人即使反编译你的apk包，也只会看到一些让人很难看懂的代码，从而达到保护代码的作用。

2.怎么混淆

打包的配置文件build.gradle里面的一段配置代码

minifyEnabled 为true就会在打包的时候进行代码混淆处理

proguardFiles getDefaultProguardFile(‘proguard-android.txt’), ‘proguard-rules.pro’

getDefaultProguardFile(‘proguard-android.txt’) 加载默认混淆配置文件，再E:\tools\adt-bundle-windows-x86_64-20140624\sdk\tools\proguard 下
proguard-rules.pro 自定义混淆文件

3.自定义混淆配置

引用的第三方库一般在说明文档里面会有使用的时候的混淆说明，注意拷到自定义混淆文件中；

webview JPush gson xutils3 #baidu location v4包

# Add project specific ProGuard rules here.# By default, the flags in this file are appended to flags specified# in /Users/jacky/Documents/Android_env/eclipse_env/android-sdk-macosx/tools/proguard/proguard-android.txt# You can edit the include path and order by changing the proguardFiles# directive in build.gradle.## For more details, see#   http://developer.android.com/guide/developing/tools/proguard.html# Add any project specific keep options here:# If your project uses WebView with JS, uncomment the following# and specify the fully qualified class name to the JavaScript interface# class:#-keepclassmembers class fqcn.of.javascript.interface.for.webview {#   public *;#}# webview + js-keepattributes *JavascriptInterface*# keep 使用 webview 的类-keepclassmembers class com.cmcc.iot.gatwaycloud.CommonWebviewActivity {   public *;}# keep 使用 webview 的类的所有的内部类-keepclassmembers  class  com.cmcc.iot.gatwaycloud.CommonWebviewActivity*{    *;}#JPush-dontwarn cn.jpush.**-keep class cn.jpush.** { *; }#==================gson==========================-dontwarn com.google.**-keep class com.google.gson.** {*;}#==================protobuf======================-dontwarn com.google.**-keep class com.google.protobuf.** {*;}################### region for xUtils-keepattributes Signature,*Annotation*-keep public class org.xutils.** {    public protected *;}-keep public interface org.xutils.** {    public protected *;}-keepclassmembers class * extends org.xutils.** {    public protected *;}-keepclassmembers @org.xutils.db.annotation.* class * {*;}-keepclassmembers @org.xutils.http.annotation.* class * {*;}-keepclassmembers class * {    @org.xutils.view.annotation.Event <methods>;}#################### end region##---------------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.cmcc.iot.gatwaycloud.http.request.** { *; }-keep class com.cmcc.iot.gatwaycloud.http.response.** { *; }##---------------End: proguard configuration for Gson  ----------# Explicitly preserve all serialization members. The Serializable interface# is only a marker interface, so it wouldn't save them.-keepclassmembers class * implements java.io.Serializable {    static final long serialVersionUID;    private static final java.io.ObjectStreamField[] serialPersistentFields;    private void writeObject(java.io.ObjectOutputStream);    private void readObject(java.io.ObjectInputStream);    java.lang.Object writeReplace();    java.lang.Object readResolve();}-keep public class * implements java.io.Serializable {*;}#baidu location-keep class com.baidu.** { *; }-keep class vi.com.gdi.bgl.android.**{*;}#baidu location# 保持哪些类不被混淆-keep public class * extends android.app.Fragment-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-keep public class * extends android.app.backup.BackupAgentHelper-keep public class * extends android.preference.Preference#如果有引用v4包可以添加下面这行-keep public class * extends android.support.v4.app.Fragment-keepclasseswithmembers class * {   # 保持自定义控件类不被混淆    public <init>(android.content.Context, android.util.AttributeSet);}-keepclasseswithmembers class * {# 保持自定义控件类不被混淆    public <init>(android.content.Context, android.util.AttributeSet, int);}

参考链接：
1. Android studio 使用心得(五)—代码混淆和破解apk
http://my.oschina.net/aibenben/blog/371889
2.Android之混淆心得与亲身体验
http://www.cnblogs.com/lee0oo0/archive/2013/12/04/3457877.html
3.anroid 使用 Gson 混淆 遇到的bug　总结
http://www.cnblogs.com/dyllove98/archive/2013/07/25/3215037.html
4.日积月累：Proguard进行源代码混淆和崩溃日志反混淆
http://blog.csdn.net/p106786860/article/details/11974863