问题1：
Unknown initial character set index ‘255’ received from server.Initial client character
解决：
因为mysql-connector-java的版本与服务器数据库版本(8.0.11)不符合，所以导致连接出错，
java架包的版本要与数据库版本对应
问题2：
The server time zone value ‘�й���ʱ��’ is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver …
解决：mysql时区问题，把端口改为：3306/?serverTimezone=America/Winnipeg&dummyparam=
