code: public List<GroupCategory> getLotGroups() {
          ClientResource resource = new ClientResource(Route.LOTGROUP.url());
  
          try {
              Representation repr = resource.get();
              return mapper.readValue(repr.getText(), new TypeReference<List<GroupCategory>>() {});
          } catch (IOException ex) {
              LEX4JLogger.log(Level.WARNING, "Could not retrieve lot groups correctly!");
              return null;
          }
      }
docs: Returns the lot groups
  
  @return the lot groups