SonarQube在安装完后运行：127.0.0.1:9000出现如下提示：
SonarQube is under maintenance. Please check back later.
Whilst waiting, you might want to check new plugins to extend the current functionality.
If you are an administrator and have no idea why this message is showing, you should read the upgrade guide
这个需要安装完后先运行http://127.0.0.1:9000/setup 更新下 SonarQube