Execution failed for task mockableAndroidJar, mockable-android- . jar already exists
问题 I am facing issue with Android Studio 3, gradle android plugin 3 with build target 27 and support lib 27.0.0 Error:Execution failed for task ':module:mockableAndroidJar'. > Output file [[...]/build/generated/mockable-android-27.v3.jar] already exists. I have to clean or manually delete all mockable-android jars from the generated folder time to time. So this means instead of getting better build times, I have to clean the project most of the times. 回答1: Simply cleanup the existing jar before