Duplicate files copied in APK META-INF/maven/com.squareup.okio/okio/pom.properties

我在导入okhttp包时出现以下问题：

Error:Execution failed for task ':app:transformResourcesWithMergeJavaResForDebug'.

> com.android.build.api.transform.TransformException: com.android.builder.packaging.DuplicateFileException:Duplicate files copied in APK META-INF/maven/com.squareup.okio/okio/pom.properties

File1: C:\Users\Administrator\.gradle\caches\modules-2\files-2.1\com.squareup.okio\okio\1.6.0\abc\okio-1.6.0.jar

File2: E:\android_studio\syc\app\build\intermediates\exploded-aar\com.umeng\message\2.4.1\jars\libs\com.umeng.message.lib_v2.4.1.jar

问题：Android Studio 引入冲突的jar包之后，会出现类似的错误。

解决方案：引入packagingOptions

android {
compileSdkVersion 23
buildToolsVersion "23.0.2"

defaultConfig {
applicationId "com.plusend.weather"
minSdkVersion 19
targetSdkVersion 23
versionCode 4
versionName "1.3"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
packagingOptions {
exclude 'META-INF/maven/com.squareup.okhttp/okhttp/pom.xml'
exclude 'META-INF/maven/com.squareup.okhttp/okhttp/pom.properties'
exclude 'META-INF/maven/com.squareup.okio/okio/pom.xml'
exclude 'META-INF/maven/com.squareup.okio/okio/pom.properties'
}
}

运行之后完美解决OK!

参考地址：http://blog.csdn.net/plusend/article/details/50243105