/**
 * Create a JDOM element, protecting the data with encoding if needed
 */
public static Element protectedElement(final String name, final String s) {
    final Element e = new Element(name);
    int badCount = 0;
    for (int i = 0; i < s.length(); i++) {
        final char c = s.charAt(i);
        if (Character.isISOControl(c) && !Character.isWhitespace(c)) {
            badCount++;
        }
    }
    if ((1.0 * badCount) / (1.0 * s.length()) > 0.1) {
        e.setAttribute("encoding", "base64");
        final Base64 b64 = new Base64();
        e.addContent(new String(b64.encode(s.getBytes())));
    } else if (badCount > 0) {
        e.setAttribute("encoding", "quoted-printable");
        final QuotedPrintableCodec qp = new QuotedPrintableCodec();
        e.addContent(new String(qp.encode(s.getBytes())));
    } else {
        e.addContent(s);
    }
    return e;
}
 

protected List<_BridgeMessageContent> extractContent(Part p) throws MessagingException, IOException {
    if (p.isMimeType("multipart/*")) {
        log.info("Found multipart content, extracting");

        List<_BridgeMessageContent> contents = new ArrayList<>();
        Multipart mp = (Multipart) p.getContent();
        int count = mp.getCount();
        for (int i = 0; i < count; i++) {
            contents.addAll(extractContent(mp.getBodyPart(i)));
        }
        return contents;
    }

    if (p.isMimeType("message/rfc822")) {
        log.info("Found nested content, extracting");
        return extractContent((Part) p.getContent());
    }

    String content = p.getContent().toString();
    String[] encodings = p.getHeader("Content-Transfer-Encoding");
    String encoding = (encodings != null && encodings.length > 0) ? encodings[0] : null;

    if (StringUtils.equalsIgnoreCase("quoted-printable", encoding)) {
        try {
            // TODO actually extract the charset properly
            // TODO read RFC to know default charset
            log.info("Transfer encoding is {}, decoding", encoding);
            content = new String(QuotedPrintableCodec.decodeQuotedPrintable(content.getBytes()));
        } catch (DecoderException e) {
            log.warn("Content transfer encoding is set to {} but enable to decode: {}", encoding, e.getMessage());
        }
    }

    if (p.isMimeType(MimeTypeUtils.TEXT_PLAIN_VALUE)) {
        log.info("Found plain text content");
        return Collections.singletonList(new BridgeMessageTextContent(content, encoding));
    }

    if (p.isMimeType(MimeTypeUtils.TEXT_HTML_VALUE)) {
        log.info("Found HTML content");
        return Collections.singletonList(new BridgeMessageHtmlContent(content, encoding));
    }

    return Collections.emptyList();
}
 

private String encodcAsQuotedPrintable( String normalizedHtml )
		throws EncoderException
{
	return new QuotedPrintableCodec( ).encode( normalizedHtml );
}