useFastInfosetForEncoding = false;
if (contentType == null) {
xmlCodec.decode(in, contentType, packet);
} else if (isMultipartRelated(contentType)) {
packet.setMessage(new XMLMultiPart(contentType, in, binding.getFeature(StreamingAttachmentFeature.class)));
} else if(isFastInfoset(contentType)) {
if (fiCodec == null) {
throw new RuntimeException(StreamingMessages.FASTINFOSET_NO_IMPLEMENTATION());
}