如何从 JavaMailSender 异常中检索附件名称？

Question

我正在使用 org.springframework.mail.javamail.JavaMailSender（Spring Framework 4.1.6）。我正在通过以下方式发送多封电子邮件：

mailSender.send(mimeMessagePreparators);

其中 mimeMessagePreparators 是一个 MimeMessagePreparator 数组。每个 MimeMessagePreparator 构建如下：

        MimeMessagePreparator mimeMessagePreparator = new MimeMessagePreparator() {
            public void prepare(MimeMessage mimeMessage) throws MessagingException {

                MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMessage, true);

                // get the subscribers of the attachment and put them as the recipients
                // of this email
                mimeMessageHelper.setTo(subscribers);

                // all email have the same from, bcc, reply to, subject, and body
                String fromEmailAddress = emailTemplate.getFromEmailAddress();
                mimeMessageHelper.setFrom(fromEmailAddress);

                // note: bcc the sender so that they get the email too
                mimeMessageHelper.setBcc(fromEmailAddress);

                // this will help on auto replies and bounce messages
                // also it should help on deliverability
                mimeMessageHelper.setReplyTo(fromEmailAddress);

                String subject = emailTemplate.getSubject();
                mimeMessageHelper.setSubject(subject);

                String emailBody = emailTemplate.getBody();
                mimeMessageHelper.setText(OPEN_EMAIL_TAGS + emailBody + CLOSE_EMAIL_TAGS, true);

                // get the physical file and add as an email attachment
                FileSystemResource file = new FileSystemResource(new File(directory, attachment.getName()));
                mimeMessageHelper.addAttachment(attachment.getName(), file);

            }
        };

我需要知道哪些电子邮件发送失败（即出现 MailException）并最终告诉用户与失败电子邮件关联的附件名称。如何从异常中检索附件名称？到目前为止，我有

try {
        mailSender.send(mimeMessagePreparators);
} catch (MailSendException mailSendException) {

        Map<Object, Exception> map = mailSendException.getFailedMessages();

        for (Map.Entry<Object, Exception> entry : map.entrySet()) {
            MimeMessage mimeMessage = (MimeMessage) entry.getKey();
            // get attachment names from mimeMessage? or preferably
            // get in a more simplistic way using a helper such as MimeMessageHelper
} catch (MailException mailException) {
    // how do I get attachment names here?
}

Answer 1

如果您有一堆 MimeMessage objects，请参阅从这里开始的 JavaMail FAQ 条目：

How do I tell if a message has attachments?

本质上，您需要遍历邮件中的各个部分，确定哪些部分代表附件，然后访问您认为代表附件的部分中的任何元数据或 headers "name"。

如何从 JavaMailSender 异常中检索附件名称？

How can attachment names be retrieved from a JavaMailSender exception?

spring

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