用Java 实现发送邮件功能

public class MailTest3 {

    public static void main(String[] args) {
         // 收件人电子邮箱
          String to = "[email protected]";
     
          // 发件人电子邮箱
          String from = "[email protected]";
     
          // 指定发送邮件的主机为 smtp.qq.com
          String host = "smtp.qq.com";  //QQ 邮件服务器
     
          // 获取系统属性
          Properties properties = System.getProperties();
     
          // 设置邮件服务器
          properties.setProperty("mail.smtp.host", host);//服务器地址
          properties.put("mail.smtp.port", "465"); // 服务器端口
     
          properties.put("mail.smtp.auth", "true");//是否要身份验证
          properties.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
          properties.put("mail.smtp.socketFactory.port", "465");
          properties.put("mail.smtp.starttls.enable", "true");
          properties.put("mail.smtp.socketFactory.fallback", "false"); 
          properties.put("mail.smtp.ssl.trust", "smtp.qq.com");
          // 获取默认session对象
          Session session = Session.getDefaultInstance(properties,new Authenticator(){
            public PasswordAuthentication getPasswordAuthentication()
            {
             return new PasswordAuthentication("[email protected]", "kfsszldekrusdjie"); //发件人邮件用户名、密码（是从QQ邮箱获取到的授权码）
            }
           });
          
          session.setDebug(true);
     
          try{
             // 创建默认的 MimeMessage 对象
             MimeMessage message = new MimeMessage(session);
     
             // Set From: 头部头字段
             message.setFrom(new InternetAddress(from));
     
             // Set To: 头部头字段
             message.addRecipient(Message.RecipientType.TO,
                                      new InternetAddress(to));
     
             // Set Subject: 头部头字段
             message.setSubject("This is the Subject Line!");
     
             // 设置消息体
             message.setText("This is actual message");
     
             // 发送消息
             Transport.send(message);
             System.out.println("Sent message successfully");
          }catch (MessagingException mex) {
             mex.printStackTrace();
          }
    }