Question

我正在使用Gmail Java SDK发送带有附件的电子邮件。

根据该文档，上传文件的最大大小为35 MB。（https://developers.google.com/gmail/api/v1/reference/users/messages/send）。

但是，实际上，我只能发送最大大小为5MB且带有附件的电子邮件，除此之外，我还会从Google收到400错误的请求太大错误。

这是我在发送前创建mime消息的代码：

    Properties props = new Properties();
    Session session = Session.getDefaultInstance(props, null);

    MimeMessage email = new MimeMessage(session);
    email.setFrom(new InternetAddress(from));
    email.setRecipient(javax.mail.Message.RecipientType.TO, new InternetAddress(to));
    email.setSubject(SUBJECT_RE + subject);
    email.setReplyTo(new Address[]{new InternetAddress(from)});
    String references = getMailReferences(messageId, service);
    if(StringUtils.isNotEmpty(references)) {
    email.setHeader(MAIL_HEADER_REFERENCES, references);
    }

    MimeBodyPart mimeBodyPart = new MimeBodyPart();
    mimeBodyPart.setContent(bodyText, "text/plain");

    Multipart multipart = new MimeMultipart("mixed");
    multipart.addBodyPart(mimeBodyPart);

    for(int i=0 ; i< attachments.size() ; i++) {
        EmailAttach attachment = attachments.get(i);
        MimeBodyPart mimeBodyPartAttachment = new MimeBodyPart();
        InputStream inputStream = new ByteArrayInputStream(attachment.getAttachmentBytes());
        DataHandler dataHandler = new DataHandler(new InputStreamDataSource(inputStream, attachment.getFileName())); 
        mimeBodyPartAttachment.setDataHandler(dataHandler);
        mimeBodyPartAttachment.setFileName(dataHandler.getName());
        multipart.addBodyPart(mimeBodyPartAttachment);
    }

    email.setContent(multipart);

在发送带有gmail附件的电子邮件时是否存在大小限制，或者是否需要更改代码以处理大附件（示例句柄/创建MimeBodyPart）（> 5MB）？

Answer 1

已解决，您需要使用带有AbstractInputStreamContent参数的send方法，并且不要对消息内容进行Base64编码：

  Message message = createMessageWithEmail(emailContent, threadId);
        ByteArrayOutputStream buffer = new ByteArrayOutputStream();
        emailContent.writeTo(buffer);
        message = service.users().messages().send(userId, message, new ByteArrayContent("message/rfc822", buffer.toByteArray())).execute();

在使用Gmail API（Java）发送电子邮件时，mimebodypart附件的最大尺寸是多少？

1 个答案: