Could not find com.android.tools.build:gradle:3.0.1

android studio升级3.1.3，gradle同时升级后报错：

Could not find com.android.tools.build:gradle:3.0.1. 
Searched in the following locations:     
https://jcenter.bintray.com/com/android/tools/build/gradl
e/3.0.1/gradle-3.0.1.pom     
https://jcenter.bintray.com/com/android/tools/build/gradl
e/3.0.1/gradle-3.0

解决办法如下：

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()
        google()//加在这里
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.1'

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

allprojects {
    repositories {
        jcenter()
        google()加在这里
    }
}

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

在以上两处中文注释处，加上google()即可解决，原理嘛，这就很明显了嘛。