一、所需jar包：
1、mail.jar
2、activation.jar
二、代码：
1、MailUtil.java
package com.gnnuit.web.mail.util; import java.util.Properties; import javax.mail.Message; import javax.mail.Session; import javax.mail.Transport; import javax.mail.internet.InternetAddress; import javax.mail.internet.MimeMessage; import javax.mail.internet.MimeMessage.RecipientType; public class MailUtil { // 发送邮件 public static void sendMail(String email, String username) throws Exception { Properties props = new Properties(); props.put("mail.transport.protocol", "smtp"); props.put("mail.host", "127.0.0.1"); Session session = Session.getDefaultInstance(props); Transport transport = session.getTransport(); transport.connect("aaa@zhaojun.com", "123456"); Message message = createMessage(session, email, username); Thread.sleep(10 * 1000); Transport.send(message); transport.close(); } // 创建邮件 public static Message createMessage(Session session, String mail, String username) throws Exception { MimeMessage message = new MimeMessage(session); // 网站管理员 message.setFrom(new InternetAddress("aaa@zhaojun.com")); message.setRecipient(RecipientType.TO, new InternetAddress(mail)); message.setSubject("BBS论坛"); message.setContent("恭喜您，" + username + "注册成功", "text/html;charset=utf-8"); return message; } }
2、LoginServlet.java
package com.gnnuit.web.mail.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 com.gnnuit.web.mail.util.MailUtil; public class LoginServlet extends HttpServlet { private static final long serialVersionUID = 1L; public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("UTF-8"); final String username = request.getParameter("username"); final String email = request.getParameter("email"); // 一个线程发邮件 new Thread() { @Override public void run() { try { // 发送邮件 MailUtil.sendMail(email, username); } catch (Exception e) { e.printStackTrace(); } } }.start(); // 一个线程显示文件 request.setAttribute("message", "注册成功"); request.getRequestDispatcher("/message.jsp").forward(request, response); } }
3、login.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <body> <form action="${pageContext.request.contextPath }/LoginServlet" method="post"> <table border="1" align="center"> <caption>用户注册</caption> <tr> <th>用户名</th> <td><input type="text" name="username"/></td> </tr> <tr> <th>邮箱</th> <td><input type="text" name="email"/></td> </tr> <tr> <td colspan="2" align="center"> <input type="submit" value="提交"/> </td> </tr> </table> </form> </body> </html>
Java Web总结二十三发送邮件,布布扣,bubuko.com
原文：http://www.cnblogs.com/FlySheep/p/3756463.html