code: public Optional<Link> getLink(LinkRelation rel) {
  
  		return links.stream() //
  				.filter(it -> it.hasRel(rel)) //
  				.findFirst();
  	}
docs: Returns the {@link Link} with the given rel.
  
  @param rel the relation type to lookup a link for.
  @return the link with the given rel or {@literal Optional#empty()} if none found.