code: public List<ContentCodingType> getContentEncoding() {
  		String value = getFirst(CONTENT_ENCODING);
  		return (value != null ? ContentCodingType.parseCodingTypes(value) : Collections.<ContentCodingType>emptyList());
  	}
docs: Return the list of {@linkplain ContentCodingType content coding types}, as
  specified by the {@code Content-Encoding} header.
  <p>Returns an empty list when the content coding type(s) are unspecified.
  @return the content coding types