摘自：http://mangocool.com/1535426841921.html
1、Establishing SSL connection without server's identity verification is not recommend
解决办法：
在mysql连接字符串url中加入ssl=true或者false即可，如下：
url=jdbc:mysql://xxx.xxx.xxx.xxx:3306/xxx?
characterEncoding=utf8
&useSSL=true
参考：
https://blog.csdn.net/guoweimelon/article/details/50810399
2、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.
解决办法：
在mysql连接字符串url中加入serverTimezone=UTC即可，如下：
url=jdbc:mysql://xxx.xxx.xxx.xxx:3306/xxx?
characterEncoding=utf8
&useSSL=true
&serverTimezone=UTC
参考：
https://blog.csdn.net/yefengzhichen/article/details/51834511
3、java.sql.SQLException: The connection
property 'zeroDateTimeBehavior' acceptable values are:
'CONVERT_TO_NULL', 'EXCEPTION' or 'ROUND'. The value 'convertToNull' is
not acceptable.
java.lang.IllegalArgumentException: No enum constant com.mysql.cj.conf.PropertyDefinitions.ZeroDatetimeBehavior.CONVERTTONULL
解决办法：
由于MySql废弃了convertToNull该写法，改为 CONVERT_TO_NULL
url=jdbc:mysql://xxx.xxx.xxx.xxx:3306/xxx?characterEncoding=utf8
&useSSL=true
&serverTimezone=UTC
&zeroDateTimeBehavior=CONVERT_TO_NULL
参考：
https://blog.csdn.net/qq_32454537/article/details/80109800
4、Exception in thread "main"
org.springframework.beans.factory.parsing.BeanDefinitionParsingException:
Configuration problem: Unable to locate Spring NamespaceHandler for XML
schema namespace [http://www.springframework.org/schema/context]
Offending resource: class path resource [spring-mybatis.xml]
参考：http://chenzhou123520.iteye.com/blog/1971322
5、Caused by: java.lang.UnsupportedClassVersionError: com/mysql/jdbc/Driver : Unsupported major.minor version 52.0
解决办法：
mysql8 依赖jdk1.8，升级jdk
6、Path does not chain with any of the trust anchors
解决办法：
应该是证书问题，把useSSL=true改为useSSL=false就好了。
参考：
https://blog.csdn.net/u013727805/article/details/80555726
