错误提示如下：

Fri May 13 09:06:04 CST 2016 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 us
ing 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 verifica
tion.

解决方法：

原来的代码：

        driver="com.mysql.jdbc.Driver";
        url="jdbc:mysql://localhost:3306/db_1";
        username="root";
        password="123qwe";

改成：

        driver="com.mysql.jdbc.Driver";
        url="jdbc:mysql://localhost:3306/db_1?characterEncoding=UTF8&useSSL=false";
        username="root";
        password="123qwe";

这样就可以了~

JDBC连接数据库时候出错