Android Studio中Gradle sync failed

问题：Android Studio中更新同步Gradle 失败

    Gradle sync failed: Could not find com.android.tools.build:gradle:3.0.1.
    Searched in the following locations:
    https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.pom
    https://jcenter.bintray.com/com/android/tools/build/gradle/3.0.1/gradle-3.0.1.jar
    Required by:
    project :
    Consult IDE log for more details (Help | Show Log) (2s 787ms)

解决办法： 在工程目录下的build.gradle文件中，添加 google() 这一行。

buildscript {
    repositories {
        //添加
        google()
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.1'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
　　　　 //添加
        google()
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}