code: public long calculateRecordCount (Collection<Path> paths) throws IOException {
      long sum = 0;
      for (Path path: paths) {
        sum += inputRecordCountProvider.getRecordCount(DatasetHelper.getApplicableFilePaths(this.fs, path, Lists.newArrayList(AVRO)));
      }
      return sum;
    }
docs: Calculate record count at given paths
  @param  paths all paths where the record count are calculated
  @return record count after parsing all files under given paths