使用 mybatis-generator 的 maven 插件可能会报出如下问题
Failed to execute goal org.mybatis.generator:mybatis-generator-maven-plugin:1.3.7:generate (default-cli) on project MyProject: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
一般来说，这种情况是数据库url写错了
来源：oschina
链接：https://my.oschina.net/hengbao666/blog/3175933