code: private Map<String, Object> getEntity(String type, String id) throws StorageException {
          try {
              JestResult response = esClient.execute(new Get.Builder(getIndexName(), id).type(type).build());
              if (!response.isSucceeded()) {
                  return null;
              }
              return response.getSourceAsObject(Map.class);
          } catch (Exception e) {
              throw new StorageException(e);
          }
      }
docs: Gets an entity.  Callers must unmarshal the resulting map.
  @param type
  @param id
  @throws StorageException