@Override
 public Attachment update(
     UriInfo uriInfo, AttachmentRepresentation representation, Attachment target) {
   target.setTitle(representation.getTitle());
   target.setMimeType(representation.getMimeType());
   target.setUrl(representation.getUrl());
   return target;
 }
 @Override
 public AttachmentRepresentation from(UriInfo uriInfo, Attachment source) {
   AttachmentRepresentation rep = new AttachmentRepresentation(source.getId(), uriInfo);
   rep.setTitle(source.getTitle());
   rep.setMimeType(source.getMimeType());
   rep.setUrl(source.getUrl());
   return rep;
 }