说明：  现在有好多初学jsp的网友经常会问数据库怎么连接啊，怎么老出错啊？所以我集中的在这写篇文章供大家参考，其实这种把数据库逻辑全部放在jsp里未必是好的做法，但是有利于初学者学习，所以我就这样做了，当大家学到一定程度的时候，可以考虑用MVC的模式开发。
(now with a lot of beginners jsp netizens often ask how database connectivity ah, ah how old mistakes? So I concentrated on writing this article for reference, but in fact this database logic placed jsp Lane is not necessarily a good practice, but is conducive to beginners learning, so I do this, when we learn a certain extent, we can consider the use of the MVC pattern of development.)