code: public static byte[] correctTypeConversions(ByteVec vec, byte[] requestedTypes) {
      byte[] metadataBytes = VecParquetReader.readFooterAsBytes(vec);
      ParquetMetadata metadata = VecParquetReader.readFooter(metadataBytes, ParquetMetadataConverter.NO_FILTER);
      byte[] roughTypes = roughGuessTypes(metadata.getFileMetaData().getSchema());
      return correctTypeConversions(roughTypes, requestedTypes);
    }
docs: Overrides unsupported type conversions/mappings specified by the user.
  @param vec byte vec holding bin\ary parquet data
  @param requestedTypes user-specified target types
  @return corrected types