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.

Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: 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.

解决方案：

mysql数据库url中添加了autoReconnect=true&failOverReadOnly=false