Fri May 19 22:56:23 CST 2017 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.
http://www.imooc.com/qadetail/159702
没设置SSL
凑够10个字
Establishing SSL connection without server's identity verification is not recommended
意思是：
如果使用SSL连接却不进行身份验证，这种方式是不推荐的。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.
意思是:
以上版本如果没有明确声明，默认建立SSL连接。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：
或者通过设置useSSL=false明确禁用SSL，或者启用SSL的同时提供服务器身份验证。
总结一下，解决题目的办法如下：
//禁用SSL
jdbc:mysql://localhost:3306/Peoples?autoReconnect=true&useSSL=false