presto-parquet/src/main/java/io/prestosql/parquet/ParquetTypeUtils.java/ParquetTypeUtils/getDescriptor
class ParquetTypeUtils:    public static Optional<RichColumnDescriptor> getDescriptor(List<PrimitiveColumnIO> columns, List<String> path)
    {
        checkArgument(path.size() >= 1, "Parquet nested path should have at least one component");
        int index = getPathIndex(columns, path);
        if (index == -1) {
            return Optional.empty();
        }
        PrimitiveColumnIO columnIO = columns.get(index);
        return Optional.of(new RichColumnDescriptor(columnIO.getColumnDescriptor(), columnIO.getType().asPrimitiveType()));
    }