JSP第六周作业

1.安装MySQL数据库，建立用户表 uid uname upwd 并插入3条数据

2.制作jsp登录页面 login.jsp 提交到dologin.jsp，使用jdbc连数据库，判断输入的用户名密码是否存在

3.如果存在，把用户名保存在SESSION中，跳转到welcome.jsp，welcome.jsp中读取session中的用户名，显示欢迎你xxx

4.若不存在，跳到登录页面。

登录界面

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>

<!DOCTYPE HTML >
<html>
  <head>       
    <title>登录界面</title>
  </head>
  
  <body bgcolor=pink>
   <form action="sjk.jsp"  method="post" >
   ID：<input type="text" name="uid"><br/><br/>
     密码：<input type="password" name="upwd"><br/><br/>
     验证码：<img src="yzm.jsp"/>
          <input type="text" name="code"/><br/><br/>
          <input type="submit" value="登录"><br/><br/><br/><br/>
   </form>
  </body >
</html>

欢迎界面

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
</head>
 
<%
    String uname = (String) request.getSession().getAttribute("uname");
%>

<body bgcolor=pink>
   <h1 style="color: black">欢迎<%=uname%>登陆！</h1>
</body>
</html>

登录失败界面

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
  </head>
  <body bgcolor=pink>
  <h1 style="color: black" >登录失败</h1>
  <h2><a href="login.jsp">登录</a></h2>
  </body>
</html>

验证码界面

<%@ page contentType="image/jpeg" language="java" import="java.util.*,java.awt.*,java.awt.image.*,javax.imageio.*" pageEncoding="utf-8"%>
 
<%!
    Color getRandColor(int fc,int bc){
        Random random = new Random();
        if(fc > 255){
            fc = 255;
        }
        if(bc < 255){
            bc = 255;
        }
        int r = fc +random.nextInt(bc-fc);
        int g = fc +random.nextInt(bc-fc);
        int b = fc +random.nextInt(bc-fc);
        return new Color(r,g,b);
    }
%>
 
<%
    //设置页面不缓存
    response.setHeader("Pragma","no-cache");
    response.setHeader("Cache-Control","no-catch");
    response.setDateHeader("Expires",0);
    //在内存中创建图象
    int width = 60;
    int height = 20;
    BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
    //创建图象
    Graphics g = image.getGraphics();
    //生成随机对象
    Random random = new Random();
    //设置背景色
    g.setColor(getRandColor(200,250));
    g.fillRect(0,0,width,height);
    //设置字体
    g.setFont(new Font("Tines Nev Roman",Font.PLAIN,18));
    //随机产生干扰线
    g.setColor(getRandColor(160,200));
    for(int i = 0; i < 255; i++){
        int x = random.nextInt(width);
        int y = random.nextInt(height);
        int xl = random.nextInt(12);
        int yl = random.nextInt(12);
    }
    //随机产生认证码,4位数字
    String sRand = "";
    for(int i = 0; i < 4; i++){
        String rand = String.valueOf(random.nextInt(10));
        sRand  += rand;
        //将认证码显示到图象中
        g.setColor(new Color(20 + random.nextInt(110),20 + random.nextInt(110),20 + random.nextInt(110)));
        g.drawString(rand,13*i+6,16);
    }
    session.setAttribute("rCode",sRand);
    //图像生效
    g.dispose();
    //输出图像到页面
    ImageIO.write(image,"JPEG",response.getOutputStream());
    out.clear();
    out = pageContext.pushBody();
%>

数据库

<%@page import="java.nio.channels.SeekableByteChannel"%>
<%@ page language="java" contentType="text/html" pageEncoding="UTF-8"%>
<%@ page import="java.sql.*"%>
<html>
<head>
<title>www.school.com</title>
</head>
<body>
    <%!public static final String DBDRIVER = "com.mysql.jdbc.Driver";
    public static final String DBURL = "jdbc:mysql://localhost:3306/mysql";
    public static final String DBUSER = "root";
    public static final String DBPASS = "root";%>
    <%
        Connection conn = null;
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        boolean flag = false;
        String name = null;
    %>
    <%
        try {
            Class.forName(DBDRIVER);
            conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
            String sql = "SELECT uname FROM stu WHERE uid=? AND upwd=?";
            pstmt = conn.prepareStatement(sql);
            pstmt.setString(1, request.getParameter("uid"));
            pstmt.setString(2, request.getParameter("upwd"));
         
            rs = pstmt.executeQuery();
            if (rs.next()) {
                name = rs.getString(1);
                flag = true;
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                if (rs != null)
                    rs.close();
                if (pstmt != null)
                    pstmt.close();
                if (conn != null)
                    conn.close();
                if (flag) {
                 request.getSession().setAttribute("uname",name);
                 request.getRequestDispatcher("welcome.jsp").forward(request,response);
                 
                   // request.getRequestDispatcher("ok.jsp").forward(request, response);
                } else {
                    response.sendRedirect("no.jsp");
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    %>
 
</body>
</html>

 

    

 

posted @ 2021-04-14 21:18  无法显示  阅读(58)  评论(0)  编辑  收藏  举报