欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页

登录注册及免密的实现

程序员文章站 2024-03-13 17:22:09
...

在实现以下功能前,我们得了解JDBC的封装以及Cookie如何使用。
对于以上不清楚的请移步我的博文JDBC工具类的封装Cookie基础使用

用户登录

1、创建用户信息表users

列名 数据类型 允许Null值
userId(主键) int
username varchar(50)
password varchar(50)
sex char(1)
email varchar (50)

注意:userId为auto_ increment,自增序列
关于如何在SqlServer中设置自增?
首先我们把主键的数据类型设为int,然后再下方属性中的标识规范中【(是表识)】设置为【是】
登录注册及免密的实现

2、login.jsp(登录页面)

<form action="/myWeb/login" method="post">
    用户名:<input type="text" name="username" value="${cookie.username.value}" /><br>
    密码:<input type="password" name="password" value="${cookie.password.value}"/><br>
    <input type="submit" value="登录">
    <a href="user_Add.html">注册</a>
</form>

3、user_Add.html(注册页面)

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>用户注册页面</title>
</head>
<body>
    <center>
        <form action="/myWeb/user/add" method="get">
            <table border="2">
                <tr>
                    <td>用户姓名</td>
                    <td><input type="text" name="username"></td>
                </tr>
                <tr>
                    <td>用户密码</td>
                    <td><input type="password" name="password"></td>
                </tr>
                <tr>
                    <td>用户性别</td>
                    <td>
                        <input type="radio" name="sex" value=""><input type="radio" name="sex" value=""></td>
                </tr>
                <tr>
                    <td>用户邮箱</td>
                    <td><input type="text" name="email"></td>
                </tr>
                <tr>
                    <td><input type="submit" value="用户注册"></td>
                    <td><input type="reset" value="重置"></td>
                </tr>
            </table>
        </form>
    </center>
</body>
</html>

4、Users(实体类)

package com.university.entity;

public class Users {
    private Integer userId;
    private String username;
    private String password;
    private String sex;
    private String email;

    public Users() {
    }

    public Users(Integer userId, String username, String password, String sex, String email) {
        this.userId = userId;
        this.username = username;
        this.password = password;
        this.sex = sex;
        this.email = email;
    }

    public Integer getUserId() {
        return userId;
    }

    public void setUserId(Integer userId) {
        this.userId = userId;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }
}

5、LoginServlet(登录逻辑处理)

package com.university.controller;

import com.university.dao.UserDao;
import com.university.entity.Users;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;

public class LoginServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        UserDao dao = new UserDao();
        Users user = null;
        //1、调用请求对象对请求体使用utf-8字符集进行重新编辑
        request.setCharacterEncoding("UTF-8");
        //2、调用请求对象读取请求体参数信息
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        //3、调用Dao将查询验证信息推送到数据库服务器上
        user = dao.login(username,password);
        //4、调用响应对象,根据验证结果将不同资源文件地址写入到响应头,交给浏览器
        response.setContentType("text/html;charset=UTF-8");
        if (user != null){
            //使用Cookie实现免密登录
            Cookie cookie1 = new Cookie("username",username);
            Cookie cookie2 = new Cookie("password",password);
            cookie1.setMaxAge(60 * 60 * 24 * 5);
            cookie2.setMaxAge(60 * 60 * 24 * 5);
            response.addCookie(cookie1);
            response.addCookie(cookie2);
            response.sendRedirect(request.getContextPath() + "/index.html");
        } else {
            response.getWriter().println("<font style='color:red;font-size:40'>用户名或密码错误</font>");
        }
    }
}

6、UserAddServlet(注册逻辑处理)

package com.university.controller;

import com.university.dao.UserDao;
import com.university.entity.Users;

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

public class UserAddServlet extends HttpServlet {
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        UserDao dao = new UserDao();
        Users user = null;
        int result = 0;
        PrintWriter out = null;
        //1、【调用请求对象】读取【请求头】参数信息,得到用户的信息信息
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        String sex = request.getParameter("sex");
        String email = request.getParameter("email");
        //2、【调用UserDao】将用户信息填充到INSERT命令并借助JDBC规范发送到数据库服务器
        user = new Users(null,username,password,sex,email);
        result = dao.add(user);
        //3、【调用响应对象】将【处理结果】以二进制形式写入到响应体
        response.setContentType("text/html;charset=UTF-8");
        out = response.getWriter();
        if (result == 1){
            response.sendRedirect(request.getContextPath() + "/login.jsp");
        } else {
            out.println("<font style='color:red;font-size:40'>用户信息注册失败</font>");
        }
    }
    //Tomcat负责销毁【请求对象】和【响应对象】
    //Tomcat负责将Http响应协议包推送到发起请求的浏览器上
    //浏览器根据响应头content-type指定编译器对响应体二进制内容编辑
    //浏览器将编辑后结果在窗口中展示给用户【结束】
}

7、web.xml(Servlet配置)

<servlet>
    <servlet-name>LoginServlet</servlet-name>
    <servlet-class>com.university.controller.LoginServlet</servlet-class>
</servlet>
<servlet>
    <servlet-name>UserAddServlet</servlet-name>
    <servlet-class>com.university.controller.UserAddServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>LoginServlet</servlet-name>
    <url-pattern>/login</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>UserAddServlet</servlet-name>
    <url-pattern>/user/add</url-pattern>
</servlet-mapping>

8、UserDao(数据库操作)

package com.university.dao;

import com.university.entity.Users;
import com.university.util.JdbcUtil;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class UserDao {
    private JdbcUtil util = new JdbcUtil();
    //用户登录
    public Users login(String username,String password){
        String sql = "select * from users where username=? and password=?";
        Users user = null;
        ResultSet rs = null;
        try {
            PreparedStatement ps = util.createStatement(sql);
            ps.setString(1,username);
            ps.setString(2,password);
            rs = ps.executeQuery();
            while (rs.next()){
                user = new Users();
                user.setUsername(rs.getString("username"));
                user.setPassword(rs.getString("password"));
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            util.close(rs);
        }
        return user;
    }

    //用户注册
    public int add(Users user){
        String sql = "insert into users(username,password,sex,email) values(?,?,?,?)";
        int result = 0;
        try {
            PreparedStatement ps = util.createStatement(sql);
            ps.setString(1,user.getUsername());
            ps.setString(2,user.getPassword());
            ps.setString(3,user.getSex());
            ps.setString(4,user.getEmail());
            result = ps.executeUpdate();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            util.close();
        }
        return result;
    }
}

9、测试

(1)查看自定义的页面

登录注册及免密的实现

(2)注册

登录注册及免密的实现

(3)点击【用户注册】按钮后跳转到【登录页面】,此时输入用户名和密码登录

登录注册及免密的实现

(4)输入错误密码或用户名

登录注册及免密的实现

(5)正式登录

登录注册及免密的实现

(6)此时退出浏览器,重新到【登录页面】,此时发现用户名与密码已经显示在页面上了,不在需要我们手动输入

登录注册及免密的实现

上一篇: Docker学习笔记杂记

下一篇: