presto-main/src/main/java/io/prestosql/split/MappedRecordSet.java/MappedRecordSet/MappedRecordSet
class MappedRecordSet:    public MappedRecordSet(RecordSet delegate, List<Integer> delegateFieldIndex)
    {
        this.delegate = requireNonNull(delegate, "delegate is null");
        this.delegateFieldIndex = Ints.toArray(requireNonNull(delegateFieldIndex, "delegateFieldIndex is null"));

        List<Type> types = delegate.getColumnTypes();
        this.columnTypes = delegateFieldIndex.stream().map(types::get).collect(toImmutableList());
    }