参考博客：https://blog.csdn.net/liaoyuecai/article/details/79903576
碰到这个错误，百度了一下，说在数据库url后添加
useSSL=false&serverTimezone=Hongkong
试了一下果然好了，可是为什么呢？
| spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true spring.datasource.driver-class-name=com.mysql.jdbc.Driver |
查了一下，说是用了最新版本的mysql包造成的，这个版本的包需要加时区
此外，如果不加useSSL=false，那么就会报警告
| Thu Apr 26 10:44:58 CST 2018 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 truststore for server certificate verification. |
意思是根据5.5.45+,5.6.26+,5.7.6+默认建立，如果没有明确设置，ssl连接默认建立
所以，您需要通过设置useSSL = false显式禁用SSL，或者设置useSSL = true并为服务器证书验证提供信任库。