code: public void delete(Query query) {
          Log.debug("Deleting by query %s", query);
          try {
              indexWriter.deleteDocuments(query);
          } catch (IOException e) {
              Log.error(e, "Error while deleting by query %s", query);
              throw new RuntimeException(e);
          }
      }
docs: Deletes all the {@link Document}s satisfying the specified {@link Query}.
  
  @param query The {@link Query} to identify the documents to be deleted.