docs: public void createLink(HalRelation rel, String... pathParams) {
      if(pathParams != null && pathParams.length > 0 && pathParams[0] != null) {
        Set<String> linkedResourceIds = linkedResources.get(rel);
        if(linkedResourceIds == null) {
          linkedResourceIds = new HashSet<String>();
          linkedResources.put(rel, linkedResourceIds);
        }
  
        // Hmm... use the last id in the pathParams as linked resource id
        linkedResourceIds.add(pathParams[pathParams.length - 1]);
  
        resource.addLink(rel.relName, rel.uriTemplate.build((Object[])pathParams));
      }
    }