JavaMail学习笔记（七）、帐号激活与忘记密码实例

一、帐户激活

在很多时候，在某些网站注册一个用户之后，网站会给这个用户注册时填写的email地址发送一封帐户激活邮件，这封邮件的内容就是一个激活帐户的链接和一段简短的文字描述，如果用户没有去邮箱将帐户激活，可能在使用网站的某些功能时就会受到限制，比如不能发贴、下载资料、评论等限制。这么做的原因应该是为了保证帐户的安全性和邮箱的有效性，以后网站如果有什么活动、资讯或系统安全通知等，可以在第一时间通知到用户。比如我在奇艺视频网站注册一个帐号之后，它就会往我注册时填写的邮箱中发一封帐户激活的邮件，邮件中有一个激活的链接，点击它就可以将你的帐户激活。如下图所示：

这个功能是怎么做到的呢，其实实现也是很简单的，说白了就是一个Update操作。

实现思路：当一个用户注册成功之后，系统向用户注册时提供的email地址发送一封邮件，邮件的内容是一个激活帐户的链接和一段简短的文字描述，这个链接的功能就是将这个帐户的状态修改成激活状态。这个功能的重点在于如何生成这个激活帐户的链接。直接可以联想到的方法就是建一个Servlet，Servlet接收一个用户名参数，Servlet拿到用户名参数之后，到数据库把这条记录load出来，做一次update操作即可。但是这样做会有风险，比如有人想在你的网站上搞破坏，注册时他填的email地址就是乱填的，这个Email地址可能根本就收不到邮件（但符合email格式），注册完成之后，然后在浏览器地址栏输入网站之前发送的帐户激活链接，并加上新注册的用户名参数，这样一来就跳过了去邮箱激活的步聚，时间久了，库中可能会留下许多无效的email地址和帐户。为了避免这个问题，解决方案是在用户注册成功之后，在发送激活帐户的链接中加一个随机码，这个随机码是将用户名和一个随机数用md5加密后的一串16进制字符串，每次用户在激活帐户的时候，都验证这个随机码是否和注册时发送的一致，这样就可以避免人为的修改激活链接达到帐户激活的功能。

二、忘记密码

当你在某网站注册一个帐户之后，发现这个帐户很久没用了，密码也忘记了，如果还记得之前注册时填写的Email，那就可以向你的email中发一个重设密码的链接，就可以重新设置你的密码。大部份网站一般都提供了根据Email找回密码的功能。实现此功能的思路：在登录界面添加一个“忘记密码“的链接，用户点击进去之后，输入用户名或Email，系统根据用户名或Email找出用户信息，并生成一个重新设置密码的链接发送到用户的邮箱中（生成链接的方式和生成帐户激活链接的方式一样），用户在邮箱中点击重设密码的链接，根据提示进入密码重设页面，重新输入新的密码即可。

功能实现步聚（帐号激活）：

1、用户注册页面

<form action="${pageContext.request.contextPath}/register" method="post">用户名：<input type="text" name="userName" value="${param.userName}"><span class="error">${errors.userName}</span><br/>密码：<input type="password" name="password" ><span class="error">${errors.password}</span><br/>确认密码：<input type="password" name="password2"><span class="error">${errors.password2}</span><br/>email：<input type="text" name="email" value="${param.email}"><span class="error">${errors.email}</span><br/><input type="submit" value="注册">
</form>

2、处理注册请求的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;/*** 用户注册*/
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", "用户名不能为空!");} else if (userName != null && userDao.findUserByName(userName) != null) {errors.put("userName", "该用户已注册!");}if (password == null || "".equals(password)) {errors.put("password","密码不能为空!");} else if (password != null && password.length() < 3) {errors.put("password","密码长度不能低于3位!");}if (password2 == null || "".equals(password2)) {errors.put("password2", "确认密码不能为空!");} else if (password2 != null && !password2.equals(password)) {errors.put("password2", "两次输入的密码不一致!");}if (email == null || "".equals(email)) {errors.put("email", "email不能为空!");} 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格式不正确!");}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);// 注册成功后,发送帐户激活链接EmailUtils.sendAccountActivateEmail(user);// 注册成功直接将当前用户保存到session中request.getSession().setAttribute("user", user);request.getRequestDispatcher("/WEB-INF/pages/registerSuccess.jsp").forward(request,response);}
}

3、激活帐户的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;/*** 帐户激活*/
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("无效的用户！");}UserDao userDao = UserDaoImpl.getInstance();User user = userDao.findUserById(id);// 得到要激活的帐户user.setActivated(GenerateLinkUtils.verifyCheckcode(user, request));// 校验验证码是否和注册时发送的一致，以此设置是否激活该帐户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、操作用户的DAO接口与实现类（UserDao和UserDaoImpl类）

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;@Overridepublic void addUser(User user) {user.setId(nextId++);user.setRandomCode(UUID.randomUUID().toString());users.put(user.getId(), user);}@Overridepublic void updateUser(User user) {users.put(user.getId(), user);}@Overridepublic User findUserById(int id) {return users.get(id);}@Overridepublic 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;}@Overridepublic 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、发送Email的工具类（EmailUtils，用于发送帐户激活链接和密码重置链接）

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";/*** 注册成功后,向用户发送帐户激活链接的邮件* @param user 未激活的用户*/public static void sendAccountActivateEmail(User user) {Session session = getSession();MimeMessage message = new MimeMessage(session);try {message.setSubject("帐户激活邮件");message.setSentDate(new Date());message.setFrom(new InternetAddress(FROM));message.setRecipient(RecipientType.TO, new InternetAddress(user.getEmail()));message.setContent("<a href='" + GenerateLinkUtils.generateActivateLink(user)+"'>点击激活帐户</a>","text/html;charset=utf-8");// 发送邮件Transport.send(message);} catch (Exception e) {e.printStackTrace();}}/*** 发送重设密码链接的邮件*/public static void sendResetPasswordEmail(User user) {Session session = getSession();MimeMessage message = new MimeMessage(session);try {message.setSubject("找回您的帐户与密码");message.setSentDate(new Date());message.setFrom(new InternetAddress(FROM));message.setRecipient(RecipientType.TO, new InternetAddress(user.getEmail()));message.setContent("要使用新的密码, 请使用以下链接启用密码:<br/><a href='" + GenerateLinkUtils.generateResetPwdLink(user) +"'>点击重新设置密码</a>","text/html;charset=utf-8");// 发送邮件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() {@Overrideprotected 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、生成帐户激活、密码重设链接的工具类（GenerateLinkUtils）

package org.study.accountactivate.util;import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;import javax.servlet.ServletRequest;import org.study.accountactivate.domail.User;/*** 生成帐户激活、重新设置密码的链接*/
public class GenerateLinkUtils {private static final String CHECK_CODE = "checkCode";/*** 生成帐户激活链接*/public static String generateActivateLink(User user) {return "http://localhost:8080/AccountActivate/activateAccount?id=" + user.getId() + "&" + CHECK_CODE + "=" + generateCheckcode(user);}/*** 生成重设密码的链接*/public static String generateResetPwdLink(User user) {return "http://localhost:8080/AccountActivate/resetPasswordUI?userName=" + user.getUserName() + "&" + CHECK_CODE + "=" + generateCheckcode(user);}/*** 生成验证帐户的MD5校验码* @param user  要激活的帐户* @return 将用户名和密码组合后，通过md5加密后的16进制格式的字符串*/public static String generateCheckcode(User user) {String userName = user.getUserName();String randomCode = user.getRandomCode();return md5(userName + ":" + randomCode);}/*** 验证校验码是否和注册时发送的验证码一致* @param user 要激活的帐户* @param checkcode 注册时发送的校验码* @return 如果一致返回true，否则返回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、实体类（User）

package org.study.accountactivate.domail;public class User {// 编号private int id;// 用户名private String userName;// 密码private String password;// emailprivate String email;// 是否激活private boolean activated;// 随机码(激活帐户与生成重设密码链接时使用)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;}}

功能实现步骤（忘记密码）：

1、登录页面

<form action="${pageContext.request.contextPath}/login" method="post"><span class="error" style="display: block;">${errors.loginError}</span>用户名：<input type="text" name="userName" value="${param.userName}"><span class="error">${errors.userName}</span><br/>密码：<input type="password" name="password"><span class="error">${errors.password}</span><br/><input type="submit" value="登录"> <a href="${pageContext.request.contextPath}/forgotPwdUI">忘记密码？</a> <a href="${pageContext.request.contextPath}/registerUI">注册</a>
</form>

2、发送重设密码申请的页面

<form action="${pageContext.request.contextPath}/forgotPwd" method="post"><span style="color: red">${requestScope.sendMailMsg}</span>用户名/邮箱：<input type="text" name="userNameOrEmail" /><span style="color: red">${requestScope.errorMsg}</span><br/><input type="submit" value="提交" /><a href=""></a>
</form>

3、处理“发送重设密码链接“请求的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;/*** 发送重设密码申请的链接*/
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;}// 发送重新设置密码的链接EmailUtils.sendResetPasswordEmail(user);request.setAttribute("sendMailMsg", "您的申请已提交成功，请查看您的"+user.getEmail()+"邮箱。");request.getRequestDispatcher("/WEB-INF/pages/forgotPwdSuccess.jsp").forward(request, response);}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request, response);}
}

4、重新设置密码的页面

<form action="${pageContext.request.contextPath}/resetPassword" method="post"><span class="error" style="display: block;">${errors.passwordError}</span>用户名：<input type="text" name="userName" value="${userName}" readonly="readonly"/><br/>新密码：<input type="password" name="newPassword" /><span class="error">${errors.newPassword }</span><br/>确认新密码：<input type="password" name="newPassword2"/><span class="error">${errors.newPassword2 }</span><br/><input type="submit" value="修改" />
</form>

5、处理重新设置密码请求的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;/*** 重新设置密码*/
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", "新密码不能为空！");}if (newPassword2 == null || "".equals(newPassword2)) {errors.put("newPassword2", "确认新密码不能为空！");}if (!newPassword.equals(newPassword2)) {errors.put("passwordError", "两次输入的密码不一致！");}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);}
}

帐户激活操作流程：

1）、注册页面