mysql-connector-java包8.0版本，支持MySQL5.5以上的所有MySQL版本 “MySQL Connector/J 8.0 is highly recommended for use with MySQL Server 8.0, 5.7, 5.6, and 5.5. Please upgrade to MySQL Connector/J 8.0.” 官方说明文档地址：https://dev.mysql.com/downloads/connector/j/
