import java.util.*;
import javax.activation.DataHandler;
import javax.activation.FileDataSource;
import javax.mail.*;
import javax.mail.internet.*;
public class SendAnEmail {
      private String to;// 收件人邮箱地址
      private String from;// 发件人邮箱地址
      private String smtpServer;// SMTP服务器地址
      private String username;// 登陆SMTP服务器的用户名
      private String password;// 登陆SMTP服务器的秘密
      private String subject;// 邮件主题
      private String content;// 邮件内容
      List<String> attachments = new ArrayList<String>();// 邮件附件
      public void setTo(String to) {
            this.to = to;
      }
      public void setFrom(String from) {
            this.from = from;
      }
      public void setSmtpServer(String smtpServer) {
            this.smtpServer = smtpServer;
      }
      public void setUsername(String username) {
            this.username = username;
      }
      public void setPassword(String password) {
            this.password = password;
      }
      public void setSubject(String subject) {
            this.subject = subject;
      }
      public void setContent(String content) {
            this.content = content;
      }
      public void attachfile(String filename) {
            attachments.add(filename);
      }
      public boolean send() {
            // 创建Session所需的Properties对象
            Properties props = new Properties();
            props.put("mail.smtp.host", smtpServer);
            props.put("mail.smtp.auth", "true");
            // 创建Session对象
            Session session = Session.getDefaultInstance(props,
            //登陆服务器的认证对象。
            new Authenticator() {
                  public PasswordAuthentication getPasswordAuthentication() {
                        return new PasswordAuthentication(username, password);
                  }
            });
            try {
                  // 实例化MimeMessage并设置相关属性
                  MimeMessage msg = new MimeMessage(session);
                  //设置发件人
                  msg.setFrom(new InternetAddress(from));
                  //设置收件人
            InternetAddress[] addresses = { new InternetAddress(to) };
                  msg.setRecipients(Message.RecipientType.TO, addresses);
                  //设置邮件主题
                  msg.setSubject(subject);
                  //通过Multipart创建邮件内容的容器对象
                  Multipart mp = new MimeMultipart();
                  MimeBodyPart mbpContent = new MimeBodyPart();
                  mbpContent.setText(content);
                  //向Multipart添加正文
                  mp.addBodyPart(mbpContent);
                  //遍历附件列表，将所有附件添加到邮件消息里。
                  for (String efile : attachments) {
                        MimeBodyPart mbpFile = new MimeBodyPart();
                        FileDataSource fds = new FileDataSource(efile);
                        mbpFile.setDataHandler(new DataHandler(fds));
                        mbpFile.setFileName(fds.getName());
                        //向Multipart添加附件
                        mp.addBodyPart(mbpFile);
                  }
                  attachments.clear();
                  msg.setContent(mp);
                  msg.setSentDate(new Date());
                  //发送邮件
                  Transport.send(msg);
            } catch (MessagingException e) {
                  e.printStackTrace();
                  return false;
            }
            return true;
      }
      public static void main(String[] argss) {
            SendAnEmail mail = new SendAnEmail();
            mail.setTo("*****@qq.com");
            mail.setFrom("*****@126.com");
            mail.setSmtpServer("smtp.126.com");
            mail.setPassword("********");
            mail.setSubject("This is an subject of a mail");
            mail.setContent("This is the content of my mail");
            mail.setUsername("*****@126.com");
            mail.attachfile("src/SendAnEmail.java");
            if (mail.send()) {
                  System.out.println("Send an Email successfully!");
            }
      }
}