JavaMail學習筆記（七）、帳號激活與忘記密碼實例

一、帳戶激活

在很多時候，在某些網站注冊一個用戶之後，網站會給這個用戶注冊時填寫的email地址發送一封帳戶激活郵件，這封郵件的內容就是一個激活帳戶的鏈接和一段簡短的文字描述，如果用戶沒有去郵箱將帳戶激活，可能在使用網站的某些功能時就會受到限製，比如不能發貼、下載資料、評論等限製。這麼做的原因應該是為了保證帳戶的安全性和郵箱的有效性，以後網站如果有什麼活動、資訊或係統安全通知等，可以在第一時間通知到用戶。比如我在奇藝視頻網站注冊一個帳號之後，它就會往我注冊時填寫的郵箱中發一封帳戶激活的郵件，郵件中有一個激活的鏈接，點擊它就可以將你的帳戶激活。如下圖所示：

這個功能是怎麼做到的呢，其實實現也是很簡單的，說白了就是一個Update操作。

實現思路：當一個用戶注冊成功之後，係統向用戶注冊時提供的email地址發送一封郵件，郵件的內容是一個激活帳戶的鏈接和一段簡短的文字描述，這個鏈接的功能就是將這個帳戶的狀態修改成激活狀態。這個功能的重點在於如何生成這個激活帳戶的鏈接。直接可以聯想到的方法就是建一個Servlet，Servlet接收一個用戶名參數，Servlet拿到用戶名參數之後，到數據庫把這條記錄load出來，做一次update操作即可。但是這樣做會有風險，比如有人想在你的網站上搞破壞，注冊時他填的email地址就是亂填的，這個Email地址可能根本就收不到郵件（但符合email格式），注冊完成之後，然後在瀏覽器地址欄輸入網站之前發送的帳戶激活鏈接，並加上新注冊的用戶名參數，這樣一來就跳過了去郵箱激活的步聚，時間久了，庫中可能會留下許多無效的email地址和帳戶。為了避免這個問題，解決方案是在用戶注冊成功之後，在發送激活帳戶的鏈接中加一個隨機碼，這個隨機碼是將用戶名和一個隨機數用md5加密後的一串16進製字符串，每次用戶在激活帳戶的時候，都驗證這個隨機碼是否和注冊時發送的一致，這樣就可以避免人為的修改激活鏈接達到帳戶激活的功能。

二、忘記密碼

當你在某網站注冊一個帳戶之後，發現這個帳戶很久沒用了，密碼也忘記了，如果還記得之前注冊時填寫的Email，那就可以向你的email中發一個重設密碼的鏈接，就可以重新設置你的密碼。大部份網站一般都提供了根據Email找回密碼的功能。實現此功能的思路：在登錄界麵添加一個“忘記密碼“的鏈接，用戶點擊進去之後，輸入用戶名或Email，係統根據用戶名或Email找出用戶信息，並生成一個重新設置密碼的鏈接發送到用戶的郵箱中（生成鏈接的方式和生成帳戶激活鏈接的方式一樣），用戶在郵箱中點擊重設密碼的鏈接，根據提示進入密碼重設頁麵，重新輸入新的密碼即可。

功能實現步聚（帳號激活）：

1、用戶注冊頁麵

<form action="${pageContext.request.contextPath}/register" method="post">
	用戶名：<input type="text" name="userName" value="${param.userName}"><span >${errors.userName}</span><br/>
	密碼：<input type="password" name="password" ><span >${errors.password}</span><br/>
	確認密碼：<input type="password" name="password2"><span >${errors.password2}</span><br/>
	email：<input type="text" name="email" value="${param.email}"><span >${errors.email}</span><br/>
	<input type="submit" value="注冊">
</form>

2、處理注冊請求的Servlet（RegisterServlet）

package org.study.accountactivate.web.servlet;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.study.accountactivate.dao.UserDao;
import org.study.accountactivate.dao.impl.UserDaoImpl;
import org.study.accountactivate.domail.User;
import org.study.accountactivate.util.EmailUtils;

/**
 * 用戶注冊
 */
public class RegisterServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
	
	private UserDao userDao = UserDaoImpl.getInstance();
       
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doPost(request, response);
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String userName = request.getParameter("userName");
		String password = request.getParameter("password");
		String password2 = request.getParameter("password2");
		String email = request.getParameter("email");
		
		Map<String, String> errors = new HashMap<String,String>();
		if (userName == null || "".equals(userName)) {
			errors.put("userName", "用戶名不能為空!");
		} else if (userName != null && userDao.findUserByName(userName) != null) {
			errors.put("userName", "該用戶已注冊!");
		}
		
		if (password == null || "".equals(password)) {
			errors.put("password","密碼不能為空!");
		} else if (password != null && password.length() < 3) {
			errors.put("password","密碼長度不能低於3位!");
		}
		
		if (password2 == null || "".equals(password2)) {
			errors.put("password2", "確認密碼不能為空!");
		} else if (password2 != null && !password2.equals(password)) {
			errors.put("password2", "兩次輸入的密碼不一致!");
		}
		
		if (email == null || "".equals(email)) {
			errors.put("email", "email不能為空!");
			
		} else if (email != null && !email.matches("[0-9a-zA-Z_-]+@[0-9a-zA-Z_-]+\\.[0-9a-zA-Z_-]+(\\.[0-9a-zA-Z_-])*")) {
			errors.put("email", "email格式不正確!");
		}
		
		if (!errors.isEmpty()) {
			request.setAttribute("errors", errors);
			request.getRequestDispatcher("/registerUI").forward(request, response);
			return;
		}
		
		User user = new User();
		user.setUserName(userName);
		user.setPassword(password);
		user.setEmail(email);
		user.setActivated(false);
		
		userDao.addUser(user);
		
		// 注冊成功後,發送帳戶激活鏈接
		EmailUtils.sendAccountActivateEmail(user);
		
		// 注冊成功直接將當前用戶保存到session中
		request.getSession().setAttribute("user", user);
		request.getRequestDispatcher("/WEB-INF/pages/registerSuccess.jsp").forward(request,response);
	}
}

3、激活帳戶的Servlet（ActivateAccountServle）

package org.study.accountactivate.web.servlet;

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

import org.study.accountactivate.dao.UserDao;
import org.study.accountactivate.dao.impl.UserDaoImpl;
import org.study.accountactivate.domail.User;
import org.study.accountactivate.util.GenerateLinkUtils;

/**
 * 帳戶激活
 */
public class ActivateAccountServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String idValue = request.getParameter("id");
		int id = -1;
		try {
			id = Integer.parseInt(idValue);
		} catch (NumberFormatException e) {
			throw new RuntimeException("無效的用戶！");
		}
		UserDao userDao = UserDaoImpl.getInstance();
		User user = userDao.findUserById(id);// 得到要激活的帳戶
		user.setActivated(GenerateLinkUtils.verifyCheckcode(user, request));// 校驗驗證碼是否和注冊時發送的一致，以此設置是否激活該帳戶
		userDao.updateUser(user);
		
		request.getSession().setAttribute("user", user);
		
		request.getRequestDispatcher("/accountActivateUI").forward(request, response);
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}
}

4、操作用戶的DAO接口與實現類（UserDao和UserDaoImpl類）

package org.study.accountactivate.dao;

import org.study.accountactivate.domail.User;

public interface UserDao {

	void addUser(User user);
	
	void updateUser(User user);
	
	User findUserById(int id);
	
	User findUserByName(String userName);
	
	User findUserByNameOrEmail(String nameOrEmail);
}

package org.study.accountactivate.dao.impl;

import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.UUID;

import org.study.accountactivate.dao.UserDao;
import org.study.accountactivate.domail.User;

public class UserDaoImpl implements UserDao {
	
	private static UserDaoImpl instance = new UserDaoImpl();
	
	private UserDaoImpl() {}
	
	public static UserDaoImpl getInstance() {
		return instance;
	}
	
	Map<Integer,User> users = new HashMap<Integer, User>();
	
	int nextId = 1;

	@Override
	public void addUser(User user) {
		user.setId(nextId++);
		user.setRandomCode(UUID.randomUUID().toString());
		users.put(user.getId(), user);
	}

	@Override
	public void updateUser(User user) {
		users.put(user.getId(), user);
	}

	@Override
	public User findUserById(int id) {
		return users.get(id);
	}

	@Override
	public User findUserByName(String userName) {
		Collection<User> userValues = users.values();
		for (Iterator<User> iterator = userValues.iterator();iterator.hasNext();) {
			User user = iterator.next();
			if (user.getUserName().equals(userName)) {
				return user;
			}
		}
		return null;
	}

	@Override
	public User findUserByNameOrEmail(String nameOrEmail) {
		Collection<User> userValues = users.values();
		for(Iterator<User> iterator = userValues.iterator();iterator.hasNext();) {
			User user = iterator.next();
			if (user.getEmail().equals(nameOrEmail) || user.getUserName().equals(nameOrEmail)) {
				return user;
			}
		}
		return null;
	}
}

5、發送Email的工具類（EmailUtils，用於發送帳戶激活鏈接和密碼重置鏈接）

package org.study.accountactivate.util;

import java.io.IOException;
import java.io.InputStream;
import java.util.Date;
import java.util.Properties;

import javax.mail.Authenticator;
import javax.mail.Message.RecipientType;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

import org.study.accountactivate.domail.User;

public class EmailUtils {
	
	private static final String FROM = "xyang81@163.com";

	/**
	 * 注冊成功後,向用戶發送帳戶激活鏈接的郵件
	 * @param user 未激活的用戶
	 */
	public static void sendAccountActivateEmail(User user) {
		Session session = getSession();
		MimeMessage message = new MimeMessage(session);
		try {
			message.setSubject("帳戶激活郵件");
			message.setSentDate(new Date());
			message.setFrom(new InternetAddress(FROM));
			message.setRecipient(RecipientType.TO, new InternetAddress(user.getEmail()));
			message.setContent("<a href='" + GenerateLinkUtils.generateActivateLink(user)+"'>點擊激活帳戶</a>","text/html;charset=utf-8");
			// 發送郵件
			Transport.send(message);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	/**
	 * 發送重設密碼鏈接的郵件
	 */
	public static void sendResetPasswordEmail(User user) {
		Session session = getSession();
		MimeMessage message = new MimeMessage(session);
		try {
			message.setSubject("找回您的帳戶與密碼");
			message.setSentDate(new Date());
			message.setFrom(new InternetAddress(FROM));
			message.setRecipient(RecipientType.TO, new InternetAddress(user.getEmail()));
			message.setContent("要使用新的密碼, 請使用以下鏈接啟用密碼:<br/><a href='" + GenerateLinkUtils.generateResetPwdLink(user) +"'>點擊重新設置密碼</a>","text/html;charset=utf-8");
			// 發送郵件
			Transport.send(message);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	public static Session getSession() {
		Properties props = new Properties();
		props.setProperty("mail.transport.protocol", "smtp");
		props.setProperty("mail.smtp.host", "smtp.163.com");
		props.setProperty("mail.smtp.port", "25");
		props.setProperty("mail.smtp.auth", "true");
		Session session = Session.getInstance(props, new Authenticator() {
			@Override
			protected PasswordAuthentication getPasswordAuthentication() {
				String password = null;
				InputStream is = EmailUtils.class.getResourceAsStream("password.dat");
				byte[] b = new byte[1024];
				try {
					int len = is.read(b);
					password = new String(b,0,len);
				} catch (IOException e) {
					e.printStackTrace();
				}
				return new PasswordAuthentication(FROM, password);
			}
			
		});
		return session;
	}
}

6、生成帳戶激活、密碼重設鏈接的工具類（GenerateLinkUtils）

package org.study.accountactivate.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import javax.servlet.ServletRequest;

import org.study.accountactivate.domail.User;

/**
 * 生成帳戶激活、重新設置密碼的鏈接
 */
public class GenerateLinkUtils {
	
	private static final String CHECK_CODE = "checkCode";
	
	/**
	 * 生成帳戶激活鏈接
	 */
	public static String generateActivateLink(User user) {
		return "https://localhost:8080/AccountActivate/activateAccount?&" + CHECK_CODE + "=" + generateCheckcode(user);
	}
	
	/**
	 * 生成重設密碼的鏈接
	 */
	public static String generateResetPwdLink(User user) {
		return "https://localhost:8080/AccountActivate/resetPasswordUI?userName=" 
				+ user.getUserName() + "&" + CHECK_CODE + "=" + generateCheckcode(user);
	}
	
	/**
	 * 生成驗證帳戶的MD5校驗碼
	 * @param user  要激活的帳戶
	 * @return 將用戶名和密碼組合後，通過md5加密後的16進製格式的字符串
	 */
	public static String generateCheckcode(User user) {
		String userName = user.getUserName();
		String randomCode = user.getRandomCode();
		return md5(userName + ":" + randomCode);
	}
	
	/**
	 * 驗證校驗碼是否和注冊時發送的驗證碼一致
	 * @param user 要激活的帳戶
	 * @param checkcode 注冊時發送的校驗碼
	 * @return 如果一致返回true，否則返回false
	 */
	public static boolean verifyCheckcode(User user,ServletRequest request) {
		String checkCode = request.getParameter(CHECK_CODE);
		return generateCheckcode(user).equals(checkCode);
	}

	private static String md5(String string) {
		MessageDigest md = null;
		try {
			md = MessageDigest.getInstance("md5");
			md.update(string.getBytes());
			byte[] md5Bytes = md.digest();
			return bytes2Hex(md5Bytes);
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
		
		return null;
	}
	
	private static String bytes2Hex(byte[] byteArray)
	{
		StringBuffer strBuf = new StringBuffer();
		for (int i = 0; i < byteArray.length; i++)
		{
			if(byteArray[i] >= 0 && byteArray[i] < 16)
			{
				strBuf.append("0");
			}
			strBuf.append(Integer.toHexString(byteArray[i] & 0xFF));
		}
		return strBuf.toString();
	}
}

7、實體類（User）

package org.study.accountactivate.domail;

public class User {
	// 編號
	private int id;
	// 用戶名
	private String userName;
	// 密碼
	private String password;
	// email
	private String email;
	// 是否激活
	private boolean activated;
	// 隨機碼(激活帳戶與生成重設密碼鏈接時使用)
	private String randomCode;
	
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	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 boolean isActivated() {
		return activated;
	}
	public void setActivated(boolean activated) {
		this.activated = activated;
	}
	public String getRandomCode() {
		return randomCode;
	}
	public void setRandomCode(String randomCode) {
		this.randomCode = randomCode;
	}
	public String getEmail() {
		return email;
	}
	public void setEmail(String email) {
		this.email = email;
	}

}

功能實現步驟（忘記密碼）：

1、登錄頁麵

<form action="${pageContext.request.contextPath}/login" method="post">
	<span  >${errors.loginError}</span>
	用戶名：<input type="text" name="userName" value="${param.userName}"><span >${errors.userName}</span><br/>
	密碼：<input type="password" name="password"><span >${errors.password}</span><br/>
	<input type="submit" value="登錄"> 
	<a href="${pageContext.request.contextPath}/forgotPwdUI">忘記密碼？</a> 
	<a href="${pageContext.request.contextPath}/registerUI">注冊</a>
</form>

2、發送重設密碼申請的頁麵

<form action="${pageContext.request.contextPath}/forgotPwd" method="post">
	<span >${requestScope.sendMailMsg}</span>
	用戶名/郵箱：<input type="text" name="userNameOrEmail" /><span >${requestScope.errorMsg}</span><br/>
	<input type="submit" value="提交" /><a href=""></a>
</form>

3、處理“發送重設密碼鏈接“請求的Servlet（ForgotPwdServlet）

package org.study.accountactivate.web.servlet;

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

import org.study.accountactivate.dao.UserDao;
import org.study.accountactivate.dao.impl.UserDaoImpl;
import org.study.accountactivate.domail.User;
import org.study.accountactivate.util.EmailUtils;

/**
 * 發送重設密碼申請的鏈接
 */
public class ForgotPwdServlet extends HttpServlet {
	
	private static final long serialVersionUID = 1L;

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String userNameOrEmail = request.getParameter("userNameOrEmail");
		UserDao userDao = UserDaoImpl.getInstance();
		User user = userDao.findUserByNameOrEmail(userNameOrEmail);
		if (user == null) {
			request.setAttribute("errorMsg", userNameOrEmail + "，不存在！");
			request.getRequestDispatcher("/forgotPwdUI").forward(request, response);
			return;
		}
		
		// 發送重新設置密碼的鏈接
		EmailUtils.sendResetPasswordEmail(user);
		
		request.setAttribute("sendMailMsg", "您的申請已提交成功，請查看您的"+user.getEmail()+"郵箱。");
		
		request.getRequestDispatcher("/WEB-INF/pages/forgotPwdSuccess.jsp").forward(request, response);
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}
}

4、重新設置密碼的頁麵

<form action="${pageContext.request.contextPath}/resetPassword" method="post">
	<span  >${errors.passwordError}</span>
	用戶名：<input type="text" name="userName" value="${userName}" readonly="readonly"/><br/>
	新密碼：<input type="password" name="newPassword" /><span >${errors.newPassword }</span><br/>
	確認新密碼：<input type="password" name="newPassword2"/><span >${errors.newPassword2 }</span><br/>
	<input type="submit" value="修改" />
</form>

5、處理重新設置密碼請求的Servlet（ResetPasswordServlet）

package org.study.accountactivate.web.servlet;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.study.accountactivate.dao.UserDao;
import org.study.accountactivate.dao.impl.UserDaoImpl;
import org.study.accountactivate.domail.User;

/**
 * 重新設置密碼
 */
public class ResetPasswordServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String userName = request.getParameter("userName");
		String newPassword = request.getParameter("newPassword");
		String newPassword2 = request.getParameter("newPassword2");
		Map<String,String> errors = new HashMap<String, String>();
		if (newPassword == null || "".equals(newPassword)) {
			errors.put("newPassword", "新密碼不能為空！");
		}
		
		if (newPassword2 == null || "".equals(newPassword2)) {
			errors.put("newPassword2", "確認新密碼不能為空！");
		}
		
		if (!newPassword.equals(newPassword2)) {
			errors.put("passwordError", "兩次輸入的密碼不一致！");
		}
		
		if (!errors.isEmpty()) {
			request.setAttribute("errors", errors);
			request.getRequestDispatcher("/resetPasswordUI?userName=" + userName).forward(request, response);
			return;
		}
		
		UserDao userDao = UserDaoImpl.getInstance();
		User user = userDao.findUserByName(userName);
		user.setPassword(newPassword);
		
		request.getRequestDispatcher("/WEB-INF/pages/resetPasswordSuccess.jsp").forward(request, response);
		
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}
}

帳戶激活操作流程：

1）、注冊頁麵