使用AS打包混淆Jar包，百度一下，一片一片的，但是很多都是零零散散的寫得不是很詳細或是直接拷貝，按照他們的教程測試總不是很順利，所以這裡我就把我個人學習AS打包混淆Jar的成果總結出來，希望對大家有幫助。個人覺得寫得還是比較詳細的

使用gradle混淆打包Jar

使用AS開發專案，引入第三方庫是非常方便的，我們只需要在build.gradle中配置一行程式碼就可以輕鬆引入我們需要的開發庫。那麼gradle可以幫我們混淆打包Jar嗎？答案是當然可以！

那麼我們如何打包Jar呢？其實我們在編譯專案的時候，AS已經幫我們在目錄build/intermediates/bundles/release/classes.jar

在你的library的build.gradle檔案中加入如下程式碼：

 task makeJar(type: proguard.gradle.ProGuardTask, dependsOn: "build") { 
   // 未混淆的jar路徑    
 injars 'build/intermediates/bundles/release/classes.jar' 
   // 混淆後的jar輸出路徑   
 outjars 'build/outputs/cocolove2-banner-1.1.0.jar'
 
  
  // 混淆協議
  configuration 'proguard-rules.pro'
}

配置混淆協議

1.我們先把AS自帶的協議配置進來中文註釋，筆者新增

# This is a configuration file for ProGuard.
# http://proguard.sourceforge.net/index.html#manual/usage.html
#
# Starting with version 2.2 of the Android plugin for Gradle, these files are no longer used. Newer
# versions are distributed with the plugin and unpacked at build time. Files in this directory are
 

# no longer maintained.

#表示混淆時不使用大小寫混合類名
-dontusemixedcaseclassnames
#表示不跳過library中的非public的類
-dontskipnonpubliclibraryclasses
#列印混淆的詳細資訊
-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
##表示不進行校驗,這個校驗作用 在java平臺上的
-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 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);
}

-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.**

# Understand the @Keep support annotation.
-keep class android.support.annotation.Keep

-keep @android.support.annotation.Keep class * {*;}

-keepclasseswithmembers class * {
    @android.support.annotation.Keep <methods>;
}

-keepclasseswithmembers class * {
    @android.support.annotation.Keep <fields>;
}

-keepclasseswithmembers class * {
    @android.support.annotation.Keep <init>(...);
}

2.AS自帶的配置文件還是不夠的，我們還需要加入如下配置
這裡只展示基本操作，在實際開發中可能需要更多依賴，要根據具體情況引入自己需要的依賴包

#下面程式碼中的xx是指我個人的配置路徑,涉及個人資訊，這裡以xx代替
#引入依賴包rt.jar（jdk路徑）
-libraryjars /xxx/xx/xx/jdk1.8.0_77.jdk/Contents/Home/jre/lib/rt.jar
#引入依賴包android.jar(android SDK路徑)
-libraryjars /xx/xx/xx/Android/sdk/platforms/android-24/android.jar
#如果用到Appcompat包，需要引入
-libraryjars /xxx/xxx/xx/xxx/MyApplication/library-banner/build/intermediates/exploded-aar/com.android.support/appcompat-v7/24.1.1/jars/classes.jar
-libraryjars /xx/xx/xx/xx/MyApplication/library-banner/build/intermediates/exploded-aar/com.android.support/support-v4/24.1.1/jars/classes.jar

#忽略警告
-ignorewarnings
#保證是獨立的jar,沒有任何專案引用,如果不寫就會認為我們所有的程式碼是無用的,從而把所有的程式碼壓縮掉,匯出一個空的jar
-dontshrink
#保護泛型
-keepattributes Signature

3.加入自己不想混淆的配置根據實際需求配置

-keep class com.cocolove2.library_banner.view.**{*;}

在命令列執行命令混淆Jar，提示BUILD SUCCESFUL表示成功！

//mac
./gradlew makeJar

//windows
gradlew makeJar

示例展示

1.首先我們要看看下我們的buildTool的配置,如下圖：

如果你的專案的buildTool#Gradle配置如上圖，那你打包混淆的第一步已經完成了，而如果選擇的是本地的gradle，當你執行./gradlew makeJar時，系統會先下載gradle,不知是網路不好還是被牆掉了，我每次嘗試下載都是等了很久，最終也沒成功。

2.在專案目錄下執行./gradlew makeJar打包輸出混淆的Jar，如下圖

3.檢視混淆結果.

混淆報錯解決辦法個人遇到的

#log提示缺少依賴Jar,或者路徑不對

解決辦法：乖乖的引入缺少的依賴jar和修改路徑

#提示如下異常
[INFO] java.io.IOException: Can't read [D:\Program 
Files\Java\jdk1.8.0_91\jre\lib\rt.jar] (Can't process class 
[com/oracle/net/Sdp$1.class] (Unsupported class version number
 [52.0] (maximum 51.0, Java 1.7)))

解決辦法：
下載最新proguard（支援Java 8的版本），然後將下載的檔案解壓。
將andorid sdk/tools/proguard/lib中的jar包，替換為剛下載解壓檔案中的lib包。