jsp第六次作业

index.jsp

<%@ 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>
<form action="mysql.jsp" method="post">
用户id:<input type="text" name="id"/><br>

密码:<input type="password" name="password"/><br>
验证码:<img src="yzm.jsp"/>
          <input type="text" name="code"/><br>
         
        <input type="submit" name="login" value="登录"><br>
</form>
  </body>
</html>

 mysql.jsp

<%@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 name FROM hhhh WHERE id=? AND password=?";
            pstmt = conn.prepareStatement(sql);
            pstmt.setString(1, request.getParameter("id"));
            pstmt.setString(2, request.getParameter("password"));
        
            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("name",name);
                 request.getRequestDispatcher("yes.jsp").forward(request,response);
                
                   // request.getRequestDispatcher("ok.jsp").forward(request, response);
                } else {
                    response.sendRedirect("no.jsp");
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    %>

</body>
</html>

 yzm.jsp

<%@ 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();
%>

 yes.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>

</head>
<body>

<%
    String name = (String) request.getSession().getAttribute("name");
%>
欢迎<%=name%>登陆
</body>
</html>

 no.jsp

<%@ 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>
    <base href="<%=basePath%>">
    
    <title>My JSP 'no.jsp' starting page</title>
    
	<meta http-equiv="pragma" content="no-cache">
	<meta http-equiv="cache-control" content="no-cache">
	<meta http-equiv="expires" content="0">    
	<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
	<meta http-equiv="description" content="This is my page">
	<!--
	<link rel="stylesheet" type="text/css" href="styles.css">
	-->

  </head>
  
  <body>
  <h1>登录失败</h1><hr>
    <h2>点击重新<a href="login.jsp">登录</a></h2>
  </body>
</html>

 

原文地址:https://www.cnblogs.com/shenyangkeji/p/14645236.html