期末测验 编程题 登录Demo系统


测验目标

分值(满分50分)

1 项目概述

1.1 需求分析

项目功能需求(14分)

图1 默认项目/ch16_xx/进入登录界面
图2 登录界面输入
图3 主界面及其相应的子资源
图4 登录界面输入错误
图5 主界面未登录进入登录界面
图6 主界面单击【用户注销】调用logout(servlet)转向login_xx.jsp进入登录界面
图7 登录2分钟内,浏览器地址栏输入index.jsp 直接进入主界面

设计、提交要求

2 数据库设计

数据库名: 登录Demo_zzh 数据表名: 用户表_zzh

图8 数据库实现(2分)----高亮要求提交截图

建表语句

-- 1. 用户
DROP TABLE IF EXISTS `用户表_zzh`;
CREATE TABLE `用户表_zzh` (
  `用户名` varchar(45) NOT NULL PRIMARY KEY,
  `密码` varchar(45) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

INSERT INTO `用户表_zzh` VALUES 
('管理员','123456'),
('杜老师','山西省晋中市');

3 项目实现

3.1 确定项目开发环境

Tomcat9.0 MySQL 8.0 JDK8

3.2 创建数据库表

见上述数据库部分

3.3 创建项目、包名、引入JAR包

图9 项目包名、文件名(2分)
包名 说明
cn.zzh.utils 工具类:数据源工具、单价计算器工具
cn.zzh.model JavaBean类
cn.zzh.dao 数据访问
cn.zzh.service 服务层
cn.zzh.servlet web servlet层
cn.zzh.filter 过滤器

jar包 在web/WEB-INF创建lib文件夹,并粘贴下列5个jar文件,

图10 jar包

项目中jar_bootstarp文件下载

web/WEB-INF/web.xml(2分)

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <welcome-file-list>
        <welcome-file>login_zzh</welcome-file>
    </welcome-file-list>
</web-app>

3.3 界面设计

图11 BootStrap登录界面(2分)

web/login_zzh.jsp(2分)

<%--
  Created by IntelliJ IDEA.
  User: zzh15
  Date: 2024/6/20
  Time: 下午5:06
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <meta charset="utf-8" />
    <title>郑佐汉的登录Demo系统.登录</title>
    <link href="css/bootstrap.min.css" rel="stylesheet">
    <style>
        body{
            width: 100%;
            height: 100%;
            overflow: hidden;
            background: url(Images/bg.png) no-repeat;
            background-size: 100% 100%;
            background-attachment: fixed;
        }
        ul a{
            width: 400px;
            background-color: rgba(255, 255, 255, 0.8);
        }

        <!-- 通过background-color设置点击状态的背景颜色 B2FF99 FFFF85 -->
        a:link {background-color:#FFFF85;}
        a:visited {background-color:#B2FF99;}
        a:hover {background-color:#FF704D;}
        a:active {background-color:#FF704D;}
    </style>

    <script src="js/bootstrap.min.js"></script>
</head>
<body>
<h3>郑佐汉的登录Demo系统</h3>
<hr>
<p>用户名:${sessionScope.user.用户名}  | <a href="logins">用户注销</a></p>

<ul class="list-group nav nav-pills">
    <li><a class="list-group-item list-group-item-success" href="login_zzh.jsp">首页 index.jsp</a></li>
    <li><a class="list-group-item list-group-item-success" href="test.html">访问test.html</a></li>
    <li><a class="list-group-item list-group-item-success" href="test.txt">访问test.txt(GBK编码)</a></li>
    <li><a class="list-group-item list-group-item-success" href="zzh.jpg">访问zzh.jpg</a></li>
    <li><a class="list-group-item list-group-item-success" href="abcd.jpg">访问不存在的abcd.jpg</a></li>
    <li><a class="list-group-item list-group-item-success" href="sub/test02.html">访问sub/test2.html</a></li>
    <li><a class="list-group-item list-group-item-success" href="sub/test02.txt">访问sub/test2.txt(GBK编码)</a></li>
    <li><a class="list-group-item list-group-item-success" href="sub/zzh2.jpg">访问sub/zzh2.jpg</a></li>
    <li><a class="list-group-item list-group-item-success" href="sub/abcd.jpg">访问不存在的sub/abcd.jpg</a></li>
</ul>
<hr>
</body>
</html>
图12 BootStrap首页界面(2分)

web/index.jsp(2分)

<%--
  Created by IntelliJ IDEA.
  User: zzh15
  Date: 2024/6/20
  Time: 下午4:55
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
  <meta charset="UTF-8">
  <title>郑佐汉的登录Demo系统</title>
  <link href="css/bootstrap.min.css" rel="stylesheet">
  <style>
    body{
      width: 100%;
      height: 100%;
      overflow: hidden;
      background: url(Images/bg.png) no-repeat;
      background-size: 100% 100%;
      background-attachment: fixed;
    }
    form{
      width: 400px;
      margin: 200px auto;
      padding: 20px 30px;
      background-color: rgba(255, 255, 255, 0.8);
    }

    form div{
      margin-bottom:10px;
    }

    a:link, a:visited, a:hover, a:active {
      text-decoration: none;
      color: rgba(0, 0, 0, 0.5);
    }
  </style>
  <script src="js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
  <form action="login" method="post" onsubmit="return login()">
    <div style="margin-bottom:20px;">
      <h4 style="text-align:center;">郑佐汉的登录Demo系统.登录</h4>
    </div>
    <div class="form-group has-success has-feedback">
      <input type="text" class="form-control" name="ue" placeholder="用户名" value="">
      <span class="glyphicon glyphicon-user form-control-feedback"></span>
    </div>
    <div class="form-group has-success has-feedback">
      <input type="password" class="form-control" name="password" placeholder="密码" value="">
      <span class="glyphicon glyphicon-lock form-control-feedback"></span>
    </div>
    <div class="d-grid gap-1">
      <button type="submit" class="btn btn-primary btn-lg btn-block">登录</button>
    </div>
    <div style="color: red">

    </div>
  </form>

</div>
</body>
</html>

3.4 配置c3p0-config.xml文件

src\c3p0-config.xml(2分)


<?xml version="1.0" encoding="UTF-8"?>
<c3p0-config>
    <default-config>
        <property name="driverClass">com.mysql.cj.jdbc.Driver</property>
        <property name="jdbcUrl">jdbc:mysql://123.57.28.35:3306/登录Demo_zzh?serverTimezone=UTC&amp;useUnicode=true&amp;characterEncoding=utf-8</property>
        <property name="user"> root </property>
        <property name="password"> Zzh123... </property>
    </default-config>
</c3p0-config>

3.5 DBUtils工具类

cn.zzh.utils.DataSourceUtils(2分)


package cn.zzh.utils;

import com.mchange.v2.c3p0.ComboPooledDataSource;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;

public class DataSourceUtils {
    // 读取 src/c3p0-config.xml 配置信息,生成静态final变量 ds
    private static final DataSource ds=new ComboPooledDataSource();

    // 静态方法 getDataSource() 获取数据源
    public static DataSource getDataSource(){
        return ds;
    }

    // 静态方法 getConnection() 获取数据库连接
    public static Connection getConnection() throws SQLException {
        return ds.getConnection();
    }
}

3.6 model

cn/zzh/model/User_zzh.java(2分)

package cn.zzh.model;

public class User_zzh {
    private String 用户名;

    private String 密码;

    public String get用户名() {
        return 用户名;
    }

    public String get密码() {
        return 密码;
    }

    public void set用户名(String 用户名) {
        this.用户名 = 用户名;
    }

    public void set密码(String 密码) {
        this.密码 = 密码;
    }

    @Override
    public String toString() {
        return "User_zzh{" +
                "用户名='" + 用户名 + '\'' +
                ", 密码='" + 密码 + '\'' +
                '}';
    }

}

3.7 dao

cn/zzh/dao/UserDao_zzh.java(2分)

package cn.zzh.dao;

import cn.zzh.model.User_zzh;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.BeanHandler;

import java.sql.SQLException;

public class UserDao_zzh {
    public User_zzh selectByUsernamePassword(String username, String password) throws SQLException {
        QueryRunner r = new QueryRunner(cn.zzh.utils.DataSourceUtils.getDataSource());
        String sql = "select * from 用户表_zzh where 用户名=? and 密码=?";
        return r.query(sql, new BeanHandler<User_zzh>(User_zzh.class),username,password);
    }
}

3.8 service

cn/zzh/service/UserService_zzh.java(2分)

package cn.zzh.service;

import cn.zzh.dao.UserDao_zzh;
import cn.zzh.model.User_zzh;

import java.sql.SQLException;

public class UserService_zzh {

    private UserDao_zzh uDao = new UserDao_zzh();

    public User_zzh login(String ue, String password) {
        User_zzh user = null;
        try {
            user = uDao.selectByUsernamePassword(ue, password);
        } catch (SQLException e) {
            e.printStackTrace();
            // 可能还需要将异常信息记录到日志中或者进行其他处理
        }
        return user; // 直接返回查询结果,无需重复查询
    }
}

3.8 servlet

cn/zzh/servlet/LoginServlet_zzh.java(4分)

package cn.zzh.servlet;

import cn.zzh.model.User_zzh;
import cn.zzh.service.UserService_zzh;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet("/login")
public class LoginServlet_zzh extends HttpServlet { // 继承自 HttpServlet
    private UserService_zzh uService = new UserService_zzh();

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        String username = request.getParameter("ue"); // 最好将变量名改为 "username" 以保持一致性
        String password = request.getParameter("password");
        User_zzh user = uService.login(username, password); // 假设 login 方法会处理密码的哈希验证
        if(user == null) {
            request.setAttribute("failMsg", "用户名或者密码错误,请重新登录!");
            request.getRequestDispatcher("/index.jsp").forward(request, response);
        } else {
            request.getSession().setAttribute("user", user);
            request.getRequestDispatcher("/login_zzh.jsp").forward(request, response);
        }
    }
}

cn/zzh/servlet/LogoutServlet_zzh.java(2分)

package cn.zzh.servlet;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet("/logins")
public class LogoutServlet_zzh extends HttpServlet {

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.getSession().removeAttribute("user");
        request.getSession().invalidate();
        request.getRequestDispatcher("/index.jsp").forward(request, response);
    }
}

3.9 编写登录过滤器

cn.zzh.filter.LoginFilter_zzh.java(6分)

登录过滤器:登录用户可访问/* 所有资源,用户没有登录仅可访问 跳转到首页

package cn.zzh.filter;

import cn.zzh.model.User_zzh;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebFilter("/*")
public class LoginFilter_zzh implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {

        HttpServletRequest req = (HttpServletRequest) request;
        HttpServletResponse resp = (HttpServletResponse) response;

        String requestURI = req.getRequestURI();
        if (requestURI.endsWith("login_zzh.jsp") || requestURI.endsWith("login")) {
            // 如果是登录页面或登录请求,则直接放行
            chain.doFilter(req, resp);
            return;
        }

        // 判断用户是否登录
        User_zzh u = (User_zzh) req.getSession().getAttribute("user");
        if (u == null) {
            // 未登录用户,转向到登录页面
            req.getRequestDispatcher("/index.jsp").forward(req, resp);
            return;
        } else {
            // 已登录用户,允许访问
            chain.doFilter(req, resp);
        }
    }

    @Override
    public void destroy() {

    }
}

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