<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>

@Autowired
    JavaMailSenderImpl mailSender;
    
    @Async
    public void SendEmail(){
        // 发送简单邮件
        SimpleMailMessage simpleMailMessage = new SimpleMailMessage();
        // 邮件主题
        simpleMailMessage.setSubject("主题");
        // 邮件内容
        simpleMailMessage.setText("正文");
        // 发送给谁
        simpleMailMessage.setTo("1233@"); 
        // 从哪里来
        simpleMailMessage.setFrom("11111@");
        mailSender.send(simpleMailMessage);
    }
    
// 启动类开启异步注解功能，及时给前台返回结果
    @EnableAsync

public void SendEmail() throws MessagingException {
        // 一个复杂的邮件
        MimeMessage mimeMessage = mailSender.createMimeMessage();
        // 组装内容
        MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, true,"utf-8");
        helper.setSubject("你好");
        helper.setText("<a>正文<a>",true);

        // 附件
        helper.addAttachment("1.jpg", new File("C:\\Users\\yh\\Desktop\\20210425165104.png"));
        helper.addAttachment("2.jpg", new File("C:\\Users\\yh\\Desktop\\20210425165207.png"));

        helper.setTo("1234@");
        helper.setFrom("11111@");

        mailSender.send(mimeMessage);
    }

spring:
  mail:
    username: 11111@
    password: 开启smtp服务获取密码
    host: smtp.
    #不同邮件后缀 host不同