数据库连接问题

[LyndonZhao]

问题1:
java.sql.SQLException: The server time zone value '???ú±ê×??±??' 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.
解决办法：
修改数据库连接url，增加serverTimezone=UTC
jdbc.url=jdbc:mysql://localhost:3306/seckill?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC

2. 问题2
   Sun Jun 02 21:55:58 CST 2019 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide

解决方法：
修改数据库连接url，增加useSSL=true
jdbc.url=jdbc:mysql://localhost:3306/seckill?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC&useSSL=true

问题3：
23:00:20.370 [http-nio-8080-exec-4] DEBUG org.springframework.web.servlet.DispatcherServlet - Could not complete request
org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.AbstractMethodError: Method com/mchange/v2/c3p0/impl/NewProxyPreparedStatement.isClosed()Z is abstract
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1006)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866)

修改依赖。
原来为：

c3p0
c3p0
0.9.1.2

修改后为：

com.mchange
c3p0
0.9.5.2

[LyndonZhao]

BTW：我的mysql版本时MySQL Server 5.7