code: @Override
    public void processEvent(QueryBatch batch) {
      try {
        batch.getClient().newDocumentManager().delete( batch.getItems() );
      } catch (Throwable t) {
        for ( BatchFailureListener<Batch<String>> listener : failureListeners ) {
          try {
            listener.processFailure(batch, t);
          } catch (Throwable t2) {
            logger.error("Exception thrown by an onBatchFailure listener", t2);
          }
        }
        for ( BatchFailureListener<QueryBatch> queryBatchFailureListener : queryBatchFailureListeners ) {
          try {
            queryBatchFailureListener.processFailure(batch, t);
          } catch (Throwable t2) {
            logger.error("Exception thrown by an onFailure listener", t2);
          }
        }
      }
    }
docs: The standard BatchListener action called by QueryBatcher.