JSP连接数据库

1、将c3p0-0.9.5.2.jar/mchange-commons-java-0.2.11.jar/ojdbc6.jar三个包放在WEB-INF的lib文件夹下，将web.xml文件放到WEB-INF下

2、在java Resources的src下新建一个包，在包里新建一个类用来连接数据库

3、编写连接数据库的代码：

package com.hanqi.web;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.mchange.v2.c3p0.ComboPooledDataSource;

public class CardDao {
    
    //
    private ComboPooledDataSource cp=new ComboPooledDataSource("helloc3p0");
    //验证输入信息
    public boolean checklogin(String cardid,String password)
    {
        boolean rtn=false;
        try {
            Connection conn=cp.getConnection();
            
            PreparedStatement ps=conn.prepareStatement("select * from bank where bcardid=?and bpassword=?");

            ps.setString(1, cardid);
            ps.setString(2, password);

            ResultSet rs=ps.executeQuery();
            rtn=rs.next();
            rs.close();
            ps.close();
            conn.close();
            
        } catch (SQLException e) {
            // TODO 自动生成的 catch 块
            e.printStackTrace();
        }
        return rtn;
    }

}
<%@page import="java.net.URLEncoder"%>
<%@page import="com.hanqi.web.CardDao"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<%
//设置不缓存页面
response.setHeader("cache-control","no-cache");
//设置定时跳转
//response.setHeader("refresh", "2;URL=http://www.baidu.com");



String cardid=request.getParameter("cardid");
String password=request.getParameter("password");
if(cardid==null||password==null||cardid.equals("")||password.equals(""))
{
    out.write("请正确登陆系统");
    response.setHeader("refresh", "3;");
    }
else{
    //检查登陆信息
    
    CardDao cd=new CardDao();
    if(cd.checklogin(cardid, password))
    {
        //out.write("登陆成功");
        //无缓存，直接发送
        response.getWriter().write("验证成功");
        
        //创建cookie
    
        Cookie ck=new Cookie("cardid",cardid);
        //设置过期时间 
        ck.setMaxAge(10*24*60*60);
        //发送 
        response.addCookie(ck);
        //
        String name="张三 ";
        //对中文进行转码 
        Cookie ck1=new Cookie("username",URLEncoder.encode("张三"));

        response.addCookie(ck1);
        //创建session
        session.setAttribute("cardid", cardid);
        session.setAttribute("username", "李四");
        //设置session的超时时间
        //默认设置是20分钟 
        //如果连续超过20分钟没有任何请求发送给服务器，session就失效
        //session.setMaxInactiveInterval(6);
                
        //页面跳转
        response.sendRedirect("main.jsp");
        //response.sendRedirect("http://www.baidu.com");
        
        //获取application属性
        int count=Integer.parseInt(application.getAttribute("count").toString());
        
        out.print("<br>网站计数器:"+count++);
        application.setAttribute("count",count);
        
    }
    else
    {
        out.write("登录失败");
        //跳回登陆页面
        response.setHeader("refresh", "2;URL=bank.jsp");
    }
    
    
    
}


%>
</body>
</html>

 

posted @ 2016-10-31 21:02  -加勒比海带  阅读(436)  评论(0)  编辑  收藏  举报