AS Duplicate files copied in APK META-INF/DEPE

错误：

Error:Execution failed for task ':k-9:transformResourcesWithMergeJavaResForRelease'.
> com.android.build.api.transform.TransformException: com.android.builder.packaging.DuplicateFileException: Duplicate files copied in APK META-INF/DEPENDENCIES
  File1: /Users/renjinlong/IdeaProjects/dataSource/womail6/k-9/libs/apache-mime4j-dom-0.7.2.jar
  File2: /Users/renjinlong/IdeaProjects/dataSource/womail6/k-9/libs/httpclient-4.3.1.jar
  File3: /Users/renjinlong/IdeaProjects/dataSource/womail6/k-9/libs/httpcore-4.3.jar
  File4: /Users/renjinlong/IdeaProjects/dataSource/womail6/k-9/libs/httpmime-4.3.1.jar

解决：

   packagingOptions{

    exclude 'META-INF/NOTICE' // will not include NOTICE file
    exclude 'META-INF/LICENSE' // will not include LICENSE file
    exclude  'META-INF/DEPENDENCIES'
}

主要是最后一个。