mysql8.x 新版本jdbc连接方式

1. 旧版本，MySQL Connector/J 5.x 版本的连接方式：
   url = jdbc:mysql://localhost:3306/thrcloud_db01?useUnicode=true&characterEncoding=utf8
   driver-class-name = com.mysql.jdbc.Driver
2. 新版本，MySQL Connector/J 6.x之后 的连接方式：
   url = jdbc:mysql://localhost:3306/thrcloud_db01?serverTimezone=UTC&characterEncoding=utf8&useUnicode=true&useSSL=false
   driver-class-name = com.mysql.cj.jdbc.Driver

　　注意：新版mysql驱动的url必须设置时区，即serverTimezone=UTC，否则会报如下错误：

java.sql.SQLException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:129) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:76) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:835) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:455) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1464) ~[druid-1.0.31.jar:1.0.31]
    at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1529) ~[druid-1.0.31.jar:1.0.31]
    at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2109) ~[druid-1.0.31.jar:1.0.31]
Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server time zone value 'Öйú±ê׼ʱ¼ä' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support.
    at sun.reflect.GeneratedConstructorAccessor29.newInstance(Unknown Source) ~[na:na]