code: public <V> V run(Callable<V,IOException> callable) throws IOException {
          return callable.call();
      }
docs: Does some calculations in batch.
  For a remote file, this can be much faster than doing the corresponding operations one by one as separate requests.
  The default implementation just calls the block directly.
  @param <V> a value type
  @param callable something to run all at once (only helpful if any mentioned files are on the same system)
  @return the callable result
  @throws IOException if remote communication failed
  @since 1.554