javamail使用方法

下面是一段用Java mail API发带附件邮件的方法，附件是读的硬盘上的文件，你参考下吧  
String message="Mail send OK！";  
  Session session=null;  
  Properties props = System.getProperties();  
  props.put("mail.smtp.host", smtpServer);  
  if(ifAuth){ //the mail server ask auth  
  props.put("mail.smtp.auth","true");  
  MailAuth smtpAuth=new MailAuth(username,password);  
  session=Session.getDefaultInstance(props, smtpAuth);  
  }else{  
  props.put("mail.smtp.auth","false");  
  session=Session.getDefaultInstance(props, null);  
  }  
  session.setDebug(isDebug);  

  Transport trans = null;
  try {  
  Message msg = new MimeMessage(session);  
  try{  
  Address from_address;
  if (displayName == null)
  from_address = new InternetAddress(from);
  else 
  from_address = new InternetAddress(from, displayName);
  msg.setFrom(from_address);  
  }catch(java.io.UnsupportedEncodingException e){  
  e.printStackTrace();  
  }  
  //InternetAddress[] address={new InternetAddress(to)};  
  InternetAddress[] address= InternetAddress.parse(to);  
  msg.setRecipients(Message.RecipientType.TO,address);  
  msg.setSubject(subject);  
   
  if (cc != null) {
  InternetAddress[] ccAddr= InternetAddress.parse(cc);  
  msg.setRecipients(Message.RecipientType.CC, ccAddr);
  }
   
   
  Multipart mp = new MimeMultipart();  
  MimeBodyPart mbp = new MimeBodyPart();  
  //mbp.setContent(content.toString(), "text/html"); //;charset=gb2312");  
  mbp.setContent(content.toString(), "text/plain"); //;charset=gb2312");  
  mp.addBodyPart(mbp);  
  if(!file.isEmpty()){//have attachment
  Enumeration efile=file.elements();  
  while(efile.hasMoreElements()){  
  mbp=new MimeBodyPart();  
  filename=efile.nextElement().toString(); //get each attachment name  
  FileDataSource fds=new FileDataSource(filename); //get the file data source
  mbp.setDataHandler(new DataHandler(fds)); //get the attachment content  
  mbp.setFileName(fds.getName()); //get the file name and include to content
  mp.addBodyPart(mbp);  
  }  
  file.removeAllElements();  
  }  
  msg.setContent(mp); // add the Multipart into mail  
  msg.setSentDate(new Date()); //set the date in mail header  

  // send  
  msg.saveChanges();  
  trans = session.getTransport("smtp");  
  trans.connect(smtpServer, username, password);  
  trans.sendMessage(msg, msg.getAllRecipients());  
  trans.close();  
   
  }catch(AuthenticationFailedException e){  
  map.put("state", "failed");  
  message="Mail send fail！Error caused：auth error!\n";  
  e.printStackTrace();  
  }catch (MessagingException e) {  
  message="Mail send fail！Error caused：\n"+e.getMessage();  
  map.put("state", "failed");  
  e.printStackTrace();  
  Exception ex = null;  
  if ((ex = e.getNextException()) != null) {  
  System.out.println(ex.toString());  
  ex.printStackTrace();  
  }  
  }