Android RPC failed

Questions
1

When I type gradle clean build, it occurrs this.

%E5%BE%AE%E4%BF%A1%E5%9B%BE%E7%89%87_20190320154205
%E5%BE%AE%E4%BF%A1%E5%9B%BE%E7%89%87_201903201542051918×570 208 KB
[root@master android_rpc]# gradle clean build --scan

FAILURE: Build failed with an exception.

  • What went wrong: A problem occurred configuring root project ‘android_rpc’.

Could not resolve all artifacts for configuration ‘:classpath’. Could not resolve com.android.tools.build:gradle:3.1.0. Required by: project : Could not resolve com.android.tools.build:gradle:3.1.0. Could not get resource ‘https://maven.google.com/com/android/tools/build/gradle/3.1.0/gradle-3.1.0.pom’. Could not GET ‘https://maven.google.com/com/android/tools/build/gradle/3.1.0/gradle-3.1.0.pom’.

2

seems to be network issue access https://maven.google.com/com/android/tools/build/gradle/3.1.0/gradle-3.1.0.pom