Java编码Base64，MimeBodyPart附件

我有一个用Base64编码的PDF文件，现在我想发送PDF并允许从邮件打开。

我正在阅读此问题，但不适用于我```js https://stackoverflow.com/a/9124625/811293

Message message = new MimeMessage(session); message.setFrom(new InternetAddress(from)); message.setSentDate(new Date()); message.setRecipients(Message.RecipientType.TO, InternetAddress.parse(sendTo)); message.setSubject("Subject - " + new Date()); Multipart multipart = new MimeMultipart();

MimeBodyPart mimeBodyPart = new MimeBodyPart(); mimeBodyPart.setContent("contentMessage", "text/html"); // YES FOR NOW SIMPLE MESSAGE multipart.addBodyPart(mimeBodyPart);

MimeBodyPart attachmentOnFly = new MimeBodyPart();

/* //In the future the PDF will be created on Fly (Will not be stored) InputStream inputStream = new FileInputStream("/path/to/encoded/Base64/file.pdf");//new ByteArrayInputStream("Bytes from source".getBytes()); ByteArrayDataSource byteArrayDataSource = new ByteArrayDataSource(inputStream, "application/pdf"); attachmentOnFly.setDataHandler(new DataHandler(byteArrayDataSource)); */

attachmentOnFly.attachFile(new File("/path/to/encoded/Base64/file.pdf")); attachmentOnFly.setHeader("Content-Type", "application/pdf"); attachmentOnFly.setHeader("Content-Transfer-Encoding", "base64"); attachmentOnFly.setDisposition(Part.ATTACHMENT); attachmentOnFly.setFileName("myFileName.pdf"); multipart.addBodyPart(attachmentOnFly);

message.setContent(multipart); Transport.send(message);

我的问题是，当收到邮件时，我无法打开PDF，但是使用Telnet替代方法却可行。

如何发送Enconded Base64 PDF，并且可以从邮件中打开它？