问题1：
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.
1.在数据库连接的url中添加useSSL=false;
2.url中添加useSSL=true，并且提供服务器的验证证书。
如果只是做一个测试的话，没必要搞证书那么麻烦啦，在连接后添加一个useSSL=false即可，例如：
jdbc:mysql://localhost:3306/test?useSSL=false
问题2：
Could not get JDBC Connection; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransien
我干脆换了一个最新的mysql jar包，重启解决了