code: @Override
      public synchronized Deque<byte[]> batch(int size) throws GeneratorException {
          if (size < 0) {
              size = 0;
          }
          Deque<byte[]> batch = new ArrayDeque<>(size);
          while (size > 0) {
              batch.add(popOne());
              size--;
          }
          return batch;
      }
docs: {@inheritDoc}