Properties properties = new Properties();
properties.setProperty("mail.host", "smtp.qq.com");
properties.setProperty("mail.transport.protocol", "smtp");
properties.setProperty("mail.smtp.auth", "true");
properties.setProperty("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
properties.setProperty("mail.smtp.port", "465");
Session session = Session.getDefaultInstance(properties);
session.setDebug(true);

MimeMessage mimeMessage = new MimeMessage(session);
mimeMessage.addRecipients(Message.RecipientType.TO, "111@qq.com");//设置收信人
mimeMessage.addRecipients(Message.RecipientType.CC, "222@qq.com");//抄送
mimeMessage.setFrom("1510161612@qq.com");//邮件发送人
mimeMessage.setSubject("测试邮件主题");//邮件主题
mimeMessage.setContent("Hello,这是一封测试邮件", "text/html;charset=utf-8");//正文

Transport transport = session.getTransport();
transport.connect("smtp.qq.com", "333@qq.com", "刚刚申请到的授权码");
transport.sendMessage(mimeMessage, mimeMessage.getAllRecipients());//发送邮件，第二个参数为收件人
transport.close();

MimeMessage mimeMessage = new MimeMessage(session);
mimeMessage.addRecipients(Message.RecipientType.TO, "111@qq.com");//设置收信人
mimeMessage.addRecipients(Message.RecipientType.CC, "222@qq.com");//抄送
mimeMessage.setFrom("333@qq.com");//邮件发送人
mimeMessage.setSubject("测试邮件主题");//邮件主题
MimeMultipart mixed = new MimeMultipart("mixed");
mimeMessage.setContent(mixed);//设置整封邮件的MIME消息体为混合的组合关系
MimeBodyPart attach1 = new MimeBodyPart();//创建附件1
MimeBodyPart attach2 = new MimeBodyPart();//创建附件2
MimeBodyPart cOntent= new MimeBodyPart();//创建邮件正文
mixed.addBodyPart(attach1);//将附件一添加到MIME消息体中
mixed.addBodyPart(attach2);//将附件二添加到MIME消息体中
mixed.addBodyPart(content);//将正文添加到消息体中
FileDataSource fds1 = new FileDataSource(new File("C:\\Users\\sang\\Desktop\\1.png"));//构造附件一的数据源
DataHandler dh1 = new DataHandler(fds1);//数据处理
attach1.setDataHandler(dh1);//设置附件一的数据源
attach1.setFileName("1.png");//设置附件一的文件名
//附件二的操作与附件一类似，这里就不一一注释了
FileDataSource fds2 = new FileDataSource(new File("C:\\Users\\sang\\Desktop\\博客笔记.xlsx"));
DataHandler dh2 = new DataHandler(fds2);
attach2.setDataHandler(dh2);
attach2.setFileName(MimeUtility.encodeText("博客笔记.xlsx"));//设置文件名时，如果有中文，可以通过MimeUtility类中的encodeText方法进行编码，避免乱码
MimeMultipart bodyMimeMultipart = new MimeMultipart("related");//设置正文的MIME类型
content.setContent(bodyMimeMultipart);//将bodyMimeMultipart添加到正文消息体中
MimeBodyPart bodyPart = new MimeBodyPart();//正文的HTML部分
bodyPart.setContent("
Hello大家好，这是一封测试邮件
","text/html;charset=utf-8");
MimeBodyPart picPart = new MimeBodyPart();//正文的图片部分
DataHandler dataHandler = new DataHandler(new FileDataSource("C:\\Users\\sang\\Desktop\\2.png"));
picPart.setDataHandler(dataHandler);
picPart.setContentID("2.png");
//将正文的HTML和图片部分分别添加到bodyMimeMultipart中
bodyMimeMultipart.addBodyPart(bodyPart);
bodyMimeMultipart.addBodyPart(picPart);
mimeMessage.saveChanges();