web.xml文件

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd"><web-app>  <servlet>    <servlet-name>mailsenderservlet</servlet-name><!--邮件发送程序-->    <servlet-class>com.email.MailSenderServlet</servlet-class>    <init-param>      <param-name>server</param-name><!--邮件服务器SMTP地址-->      <param-value>smtp.163.com</param-value>    </init-param>    <init-param>      <param-name>port</param-name><!--邮件服务器SMTP端口-->      <param-value>25</param-value>    </init-param>    <init-param>      <param-name>address</param-name><!--邮件地址-->      <param-value>username@163.com</param-value>    </init-param>    <init-param>      <param-name>username</param-name><!--邮件账号-->      <param-value>username</param-value>    </init-param>    <init-param>      <param-name>password</param-name><!--密码-->      <param-value>******</param-value>    </init-param>    <init-param>      <param-name>validate</param-name><!--SMTP服务器是否要求验证-->      <param-value>true</param-value>    </init-param>    <init-param>      <param-name>time</param-name><!--扫描数据库时间间隔（分钟）-->      <param-value>5</param-value>    </init-param>    <load-on-startup>1</load-on-startup>  </servlet></web-app>

servlet:

package com.email;

import javax.servlet.*;import javax.servlet.http.*;import java.io.*;

public class MailSenderServlet    extends HttpServlet {  private MailSender sender;  private Thread t;

  public void init() throws ServletException {    sender = new MailSender();    sender.setRoot(root);    String server = getInitParameter("server");    String port = getInitParameter("port");    String address = getInitParameter("address");    String username = getInitParameter("username");    String password = getInitParameter("password");    if (server == null || port == null || address == null || username == null ||        password == null) {      System.out.println("系统文件web.xml错误：邮件发送程序初始化失败！");      return;    }    sender.setServer(server);    sender.setPort(port);    sender.setAddress(address);    sender.setUsername(username);    sender.setPassword(password);