code: @Override
      public ServiceInstance<T> queryForInstance(String name, String id) throws Exception
      {
          String path = pathForInstance(name, id);
          try
          {
              byte[] bytes = client.getData().forPath(path);
              return serializer.deserialize(bytes);
          }
          catch ( KeeperException.NoNodeException ignore )
          {
              // ignore
          }
          return null;
      }
docs: Return a group instance POJO
  
  @param name name of the group
  @param id ID of the instance
  @return the instance or <code>null</code> if not found
  @throws Exception errors