我想使用注解@scheduled using cron来调度一个方法，例如，我希望该方法应该每天在客户机指定的时间内执行。因此，我想从db中获取cron值，以便让客户机能够在任何时候执行该方法。这是我的方法，它在上午10:00自动发送电子邮件到给定的地址，所以我的目标是使10:00动态。谢谢你的帮助。

@Scheduled(cron = "0 00 10* * ?")
    public void periodicNotification()  {
        JavaMailSenderImpl jms = (JavaMailSenderImpl) sender;
        MimeMessage message = jms.createMimeMessage();
        MimeMessageHelper helper;
        try {
            helper = new MimeMessageHelper(message, MimeMessageHelper.MULTIPART_MODE_MIXED_RELATED, StandardCharsets.UTF_8.name());

        List<EmailNotification> emailNotifs = enr.findAll();
        for (EmailNotification i : emailNotifs) 
        {
            helper.setFrom("smsender4@gmail.com");
            List<String> recipients = fileRepo.findWantedEmails(i.getDaysNum());
            //List<String> emails = recipientsRepository.getScheduledEmails();

            String[] to = recipients.stream().toArray(String[]::new);
            helper.setTo(to);
            helper.setText(i.getMessage());
            helper.setSubject(i.getSubject());
            sender.send(message);
            System.out.println("Email successfully sent to: " + Arrays.toString(to));
        }
        }
        catch (MessagingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }