Error:Execution failed for task ‘:app:javaPreCompileDebug'.Annotation processors must be explicitly declared now. The following dependencies on the compile classpath are found to contain annotation processor. Please add them to the annotationProcessor configuration. - butterknife-7.0.1.jar (com.jakewharton:butterknife:7.0.1) Alternatively, set android.defaultConfig.javaCompileOptions.annotationProcessorOptions.includeCompileClasspath = true to continue with previous behavior. Note that this option is deprecated and will be removed in the future. See https://developer.android.com/r/tools/annotation-processor-error-message.html for more details.