<dependency>
    <groupId>javax.mail</groupId>
    <artifactId>mail</artifactId>
    <version>1.4.1</version>
</dependency>

@Data
public class EmailVo {
    private String receiveMail;
    private String subject;
    private String content;
}

@Configuration
public class EmailConfig {

// 我在Nacos配置中心配的user和password
    @Value("${mail.user}")
    private String mailUser;

    @Value("${mail.password}")
    private String mailPassword;

    @Bean
    public Properties props() {
        // 创建Properties 类用于记录邮箱的一些属性
        Properties props = new Properties();
        // 表示SMTP发送邮件，必须进行身份验证
        props.put("mail.smtp.auth", "true");
        //此处填写SMTP服务器
        props.put("mail.smtp.host", "smtp.qq.com");
        //端口号，QQ邮箱端口587
        props.put("mail.smtp.port", "587");
        // 此处填写，写信人的账号
        props.put("mail.user", mailUser);
        // 此处填写16位STMP口令
        props.put("mail.password", mailPassword);
        return props;
    }

    @Bean
    public Authenticator authenticator(Properties props) {
        // 构建授权信息，用于进行SMTP进行身份验证
        return new Authenticator() {
            protected PasswordAuthentication getPasswordAuthentication() {
                // 用户名、密码
                String userName = props.getProperty("mail.user");
                String password = props.getProperty("mail.password");
                return new PasswordAuthentication(userName, password);
            }
        };
    }
}

@RestController
public class SendEmailController {

    @Autowired
    private Properties props;

    @Autowired
    private Authenticator authenticator;

    @PostMapping("/email/send")
    public R sendEmail(@RequestBody EmailTo emailTo) throws MessagingException {
        // 使用环境属性和授权信息，创建邮件会话
        Session mailSession = Session.getInstance(props, authenticator);
        // 创建邮件消息
        MimeMessage message = new MimeMessage(mailSession);
        // 设置发件人
        InternetAddress form = new InternetAddress(props.getProperty("mail.user"));
        message.setFrom(form);
        // 设置收件人的邮箱
        InternetAddress to = new InternetAddress(emailTo.getReceiveMail());
        message.setRecipient(Message.RecipientType.TO, to);
        // 设置邮件标题
        message.setSubject(emailTo.getSubject());
        // 设置邮件的内容体
        message.setContent(emailTo.getContent(), "text/html;charset=UTF-8");
        // 最后当然就是发送邮件啦
        Transport.send(message);

        return R.ok();
    }

}