安卓Duplicate files copied in APK META-INF/LICENSE

Caused by: java.lang.RuntimeException: com.android.build.api.transform.TransformException: com.android.builder.packaging.DuplicateFileException: Duplicate files copied in APK META-INF/LICENSE
    File1: E:\idea\MyApplication\android\libs\jackson-annotations-2.2.3.jar
    File2: E:\idea\MyApplication\android\libs\jackson-core-2.2.3.jar
    File3: E:\idea\MyApplication\android\libs\jackson-databind-2.2.3.jar

这是由于jar包中引入类有冲突引起的解决方法 为在build.gradle中加入这一段代码

  packagingOptions {
        exclude 'META-INF/DEPENDENCIES'
        exclude 'META-INF/NOTICE'
        exclude 'META-INF/LICENSE'
        exclude 'META-INF/LICENSE.txt'
        exclude 'META-INF/NOTICE.txt'
    }