jodd-mail/src/main/java/jodd/mail/ReceivedEmail.java
protected void processPart(final Part part) throws MessagingException, IOException {
		final Object content = part.getContent();

		if (content instanceof String) {
			addStringContent(part, (String) content);
		} else if (content instanceof Multipart) {
			processMultipart((Multipart) content);
		} else if (content instanceof InputStream) {
			addAttachment(part, (InputStream) content, attachmentStorage);
		} else if (content instanceof MimeMessage) {
			final MimeMessage mimeMessage = (MimeMessage) content;
			attachedMessage(new ReceivedEmail(mimeMessage, false, attachmentStorage));
		} else {
			addAttachment(part, part.getInputStream(), attachmentStorage);
		}
	}
protected void processPart(final Part part) throws MessagingException, IOException {
		final Object content = part.getContent();

		if (content instanceof String) {
			addStringContent(part, (String) content);
		} else if (content instanceof Multipart) {
			processMultipart((Multipart) content);
		} else if (content instanceof InputStream) {
			addAttachment(part, (InputStream) content, attachmentStorage);
		} else if (content instanceof MimeMessage) {
			final MimeMessage mimeMessage = (MimeMessage) content;
			attachedMessage(new ReceivedEmail(mimeMessage, false, attachmentStorage));
		} else {
			addAttachment(part, part.getInputStream(), attachmentStorage);
		}
	}
Process part of the received message. All parts are simply added to the {@link ReceivedEmail},
i.e. hierarchy is not saved.

@param part {@link Part} of received message
@throws IOException        if there is an error with the content.
@throws MessagingException if there is an error.