解决Establishing SSL connection without server‘s identity verification is not recommended.

每次从数据库中进行查询或者其他操作控制台都会出现以下警告，虽说不是error，但是很显眼。。
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.

解决方法：在配置文件中的连接数据库的URL后面添加 useSSL=false

方案二：可能是连接数据库的驱动版本问题(5.1.38)，更换成其他版本即可。