本文是介绍在一个小的JAVAWeb项目中，利用邮箱帮用户找回密码。
效果展示
需要一个发送邮件的jar包 ： javax.mail .jar
1.JSP页面（设置邮箱输入框）
<%@ 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" rel="external nofollow" >
<script type="text/javascript" src="bootstrap/js/bootstrap.min.js"></script>
</head>
<body>
<div style="text-align: center" width="300px" height="200px">
<form action="RetrievePassword.do" 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>
2.Servlet代码（根据用户输入的邮箱账号找到用户，并生成发送邮件类的实例，再设置收件人和要发送的内容，最后发送邮件）
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//获取用户的邮箱
String email = request.getParameter("email");
Admin admin = null;
User user = null;
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
admin = adminService.getAdminByEmail(email);
if(admin!=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："+admin.getPassword());
out.println("<script>alert('恭喜，找回密码成功');window.location.href='login.jsp'</script>");
} else {
user = userService.getUserByEmail(email);
if(user!=null) {
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>");
}
3.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 {
// 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;
}
}
注意此处用的授权码，需要自己登录邮箱去设置，如163邮箱设置如下：
