import javax.mail.Authenticator;
import javax.mail.PasswordAuthentication;
public class Email_Autherticator extends Authenticator {
  String username = "你郵箱的用戶名";
  String password = "你郵箱的密碼";
  public Email_Autherticator() {
 super();
  }
  public Email_Autherticator(String user,String pwd){
 super();
 username = user;
 password = pwd;
  }
  public PasswordAuthentication getPasswordAuthentication(){
 return new PasswordAuthentication(username,password);
  }
}

import java.util.Date;
import java.util.Properties;
import javax.mail.Address;
import javax.mail.Authenticator;
import javax.mail.Message;
import javax.mail.SendFailedException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
public class Mail {
  private String host = "smtp.126.com";
  private String mail_head_name = "this is head of this mail";
  private String mail_head_value = "this is head of this mail";
  private String mail_to = "254173774@qq.com";
  private String mail_from = "hackboyo@126.com";
  private String mail_subject = "this is the subject of this test mail";
  private String mail_body = "this is mail_body of this test mail";
  private String personalName = "我的郵件";
  public void sendMail() throws SendFailedException{
 try {
   Properties props = new Properties();//獲取系統(tǒng)環(huán)境
   Authenticator auth = new Email_Autherticator();//進行郵件服務(wù)用戶認(rèn)證
   props.put("mail.smtp.host", host);
   props.put("mail.smtp.auth", "true");
   System.out.println(props);
   Session session = Session.getDefaultInstance(props,auth);
   //設(shè)置session,和郵件服務(wù)器進行通訊
   MimeMessage message = new MimeMessage(session);
   message.setContent("Hello","text/plain");//設(shè)置郵件格式
   message.setSubject(mail_subject);//設(shè)置郵件主題
   message.setText(mail_body);//設(shè)置郵件內(nèi)容
   message.setHeader(mail_head_name, mail_head_value);//設(shè)置郵件標(biāo)題
   message.setSentDate(new Date());//設(shè)置郵件發(fā)送時期
   Address address = new InternetAddress(mail_from,personalName);
   message.setFrom(address);//設(shè)置郵件發(fā)送者的地址
   Address toaddress = new InternetAddress(mail_to);//設(shè)置郵件接收者的地址
   message.addRecipient(Message.RecipientType.TO,toaddress);
   System.out.println(message);
   Transport.send(message);
   System.out.println("Send Mail Ok!");
 } catch (Exception e) {
   e.printStackTrace();
 }
 //return flag;
  }
}

public class Test {
  public static void main(String[] args) {
 Mail m = new Mail();
 try {
   m.sendMail();
 } catch (Exception e) {
 }
  }
}