Java完成密码找回功能

以你之姓@ 2023-06-09 15:25 65阅读 0赞

# 说明：以讲解Email操作为主，不过多描述数据库操作，有javaweb基础的话，我相信能够举一反三。   ![20181101234911824.png][] #

# 必要的准备工作(略)： #

**1.导入jar包**  
需要一个发送邮件的jar包 ： javax.mail .jar  
下载jar包：链接：https://pan.baidu.com/s/1t9G\_V2aaa\_FbHx51pbB1Xg   
                    提取码：s4a5

**2*.(略写)*数据库相关操作(以我的为例)，这里不描述数据库的创建以后面截图为准。**  
UserDaoImpl.java

@Override
    	public User queryUserByEmail(String email) {
    		Connection conn=null;
    		User user=null;
    		PreparedStatement pstmt=null;
    		ResultSet rs=null;
    		try {
    		String sql="select * from userrejister where email=?";
    		Object[] params={email};
    		//DBUtil为工具类
    		rs=DBUtil.executeQuery(sql, params);
    		if(rs.next()){
    				String username=rs.getString("username");
    				String password=rs.getString("password");
    				String school=rs.getString("school");
    				String sex=rs.getString("sex");
    				String tel=rs.getString("tel");
    				Integer Id=rs.getInt("id");
    				String age=rs.getString("age");
    				String Email=rs.getString("email");
    				user=new User(username,password,school,sex,tel,Id,age,Email);
    			}
    			return user;
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    			return null;
    		}finally{
    			JDBCUtil.close(rs, pstmt, conn);
    		}
    	}

UserServiceImpl.java

@Override
    	public User getUserByEmail(String email) {
    		return ud.queryUserByEmail(email);
    	}

DBUtil.java

public static Connection conn=null;
    public static PreparedStatement pstmt=null;
    public static ResultSet rs=null;	
    public static PreparedStatement createPreparedStatement(String sql,Object[] params){		
    		try {
    			conn=JDBCUtil.getConnection();
    			pstmt=conn.prepareStatement(sql);
    			if(params!=null){
    				for(int i=0;i<params.length;i++){
    					pstmt.setObject(i+1, params[i]);
    				}	
    			}
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
    		return pstmt;
    	}
    		
    public static ResultSet executeQuery(String sql,Object[] params){
    		//这里的rs不能关闭，因为返回的是结果集，其他类还要使用！！！！！。
    		
    		try {
    			pstmt=createPreparedStatement(sql, params);
    			rs=pstmt.executeQuery();
    		}catch (SQLException e) {
    				e.printStackTrace();
    				return null;
    			}
    		return rs;
    		}

User.java(实体类)

package com.entity;
    import java.util.*;
    import java.sql.*;
    public class User {
    	private String password;
    	private String school;
    	private String sex;
    	private String tel;
    	private Integer id;
    	private String age;
    	private String email;
    	private String username;
    
    }

3.数据库创建  
![20191021210300539.png][]

4.写jsp测试页面  
input.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    	pageEncoding="UTF-8"%>
    <!DOCTYPE html>
    <html lang="en">
    <head>
    <meta charset="utf-8">
    <title>找回密码-图书管理系统</title>
    <link rel="stylesheet" href="bootstrap/css/bootstrap.min.css">
    <script type="text/javascript" src="bootstrap/js/bootstrap.min.js"></script>
    </head>
    <body>
    	<div style="text-align: center" width="300px" height="200px">
    		<form action="GetBackPassword" method="post">
     
     
    			<input type="email" name="email" id="email" width="100px"
    				height="60px" style="margin-top: 100px" placeholder="请输入您的邮箱地址"
    				required> <br>
    			<br>
     
    			<button type="submit" class="btn btn-success" id="button"
    				width="100px" height="60px">找回密码</button>
     
    		</form>
    		<br>
    		<br>
     
    		<button type="button" class="btn btn-primary" id="button"
    			onclick="backLogin()" width="100px" height="60px">返回登录页面</button>
    	</div>
    	<script type="text/javascript">
    		function backLogin() {
    			window.location.href = "login.jsp"
    		}
    	</script>
    </body>
    </html>

说明：这时候准备工作已经完成，下面将具体讲解 **发送邮件类** 和 **Servlet代码**

# 发送邮件类     #

package com.bookms.util;
     
    import javax.mail.MessagingException;
    import javax.mail.NoSuchProviderException;
    import javax.mail.Session;
    import javax.mail.Transport;
    import javax.mail.internet.InternetAddress;
    import javax.mail.internet.MimeMessage;
    import java.util.Date;
    import java.util.Properties;
     
    public class SendMail {
     
    	//hpzy_rz_liuhx@163.com
    	// 发件人的邮箱账号如：xxx@163.com
    	public static String sendEmailAccount = "";
    	// 发件人的邮箱的授权码(自己在邮箱服务器中开启并设置)
    	public static String sendEmailPassword = "";
    	// 发件人邮箱的SMTP服务器地址，如：smtp.163.com
    	public static String sendEmailSMTPHost = "smtp.163.com";
    	// 收件人的邮箱账号
    	public static String receiveMailAccount = "";
     
    	// 把发送邮件封装为函数，参数为收件人的邮箱账号和要发送的内容
    	public void sendMail(String receiveMailAccount, String mailContent) {
    		// 创建用于连接邮件服务器的参数配置
    		Properties props = new Properties();
    		// 设置使用SMTP协议
    		props.setProperty("mail.transport.protocol", "smtp");
    		// 设置发件人的SMTP服务器地址
    		props.setProperty("mail.smtp.host", sendEmailSMTPHost);
    		// 设置需要验证
    		props.setProperty("mail.smtp.auth", "true");
     
    		// 根据配置创建会话对象, 用于和邮件服务器交互
    		Session session = Session.getInstance(props);
    		// 设置debug模式，便于查看发送过程所产生的日志
    		session.setDebug(true);
     
    		try {
    			// 创建一封邮件
    			MimeMessage message = createMimeMessage(session, sendEmailAccount, receiveMailAccount, mailContent);
     
    			// 根据 Session 获取邮件传输对象
    			Transport transport = session.getTransport();
     
    			transport.connect(sendEmailAccount, sendEmailPassword);
     
    			// 发送邮件, 发到所有的收件地址, 通过message.getAllRecipients() 可以获取到在创建邮件对象时添加的所有收件人
    			transport.sendMessage(message, message.getAllRecipients());
     
    			// 关闭连接
    			transport.close();
    		} catch (NoSuchProviderException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} catch (MessagingException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} catch (Exception e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
    	}
     
    	/**
    	 * 
    	 * @param session
    	 *            和服务器交互的会话
    	 * @param sendMail
    	 *            发件人邮箱
    	 * @param receiveMail
    	 *            收件人邮箱
    	 * @return
    	 * @throws Exception
    	 */
    	public static MimeMessage createMimeMessage(Session session, String sendMail, String receiveMail,
    			String mailContent) throws Exception {
    		// 创建一封邮件
    		MimeMessage message = new MimeMessage(session);
     
    		// 设置发件人姓名和编码格式
    		message.setFrom(new InternetAddress(sendMail, "图书管理系统", "UTF-8"));
     
    		// 收件人
    		message.setRecipient(MimeMessage.RecipientType.TO, new InternetAddress(receiveMail, "尊敬的用户", "UTF-8"));
     
    		// 设置邮件主题
    		message.setSubject("找回密码提醒", "UTF-8");
     
    		// 设置邮件正文
    		message.setContent(mailContent, "text/html;charset=UTF-8");
     
    		// 设置发件时间
    		message.setSentDate(new Date());
     
    		// 保存设置
    		message.saveChanges();
     
    		return message;
    	}
     
    }

**具体说明：**  
![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxODc3MTg0_size_16_color_FFFFFF_t_70][]

发件人的邮箱：这里可以自己***手动设置***  
\*\*发件人的邮箱授权码（重点）：也需要***手动设置***，稍后会已截图的形式呈现哪里找授权码。  
 收件人的邮箱账号：这里不用手动设置，利用JSP传递邮箱给Servlet，再传递给此变量即可。注意：jsp输入的邮箱要你在数据库中保存好了的呀...

授权码获得途径：自己设置授权码，然后在sendEmail中手动添加进去，即可。  
![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxODc3MTg0_size_16_color_FFFFFF_t_70 1][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxODc3MTg0_size_16_color_FFFFFF_t_70 2][]

# Servlet类 #

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		request.setCharacterEncoding("utf-8");
    		response.setHeader("Content-Type","text/html;charset=utf-8");
    		//获取用户的邮箱
    		String email = request.getParameter("email");
    		PrintWriter out = response.getWriter();
    		//实例化一个发送邮件的对象
    		SendMail mySendMail = new SendMail();
    		//根据邮箱找到该用户信息
    		IUserService service=new UserServiceImpl();
    		User user = service.getUserByEmail(email);
    		if(user!=null) {
    			//设置收件人和消息内容
    			mySendMail.sendMail(email, "图书管理系统提醒，您的密码为："+user.getPassword());
    			out.println("<script>alert('恭喜，找回密码成功');window.location.href='login.jsp'</script>");
    		} 
    		out.println("<script>alert('该邮箱尚未注册！请重新输入');window.location.href='retrievePassword.jsp'</script>");	
    	}

最后会将密码发送给该邮箱的用户：  
![20181101234911824.png][]

[20181101234911824.png]: /images/20230531/a50b161c5f854c3e8aa4d580b9fff133.png
[20191021210300539.png]: /images/20230531/e9a1fadf944d4ca78e5d732fe1b407ab.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxODc3MTg0_size_16_color_FFFFFF_t_70]: /images/20230531/9b8257a7edc4423ab5dc78e28a4db6cb.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxODc3MTg0_size_16_color_FFFFFF_t_70 1]: /images/20230531/d016c64a299841b5933432e17db036c3.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQxODc3MTg0_size_16_color_FFFFFF_t_70 2]: /images/20230531/d299d2b5ca144d52b18231ba9d53e6a7.png