NamedTypeSignature namedTypeSignature = fields.get(i).getNamedTypeSignature();
String name = namedTypeSignature.getName().get().toLowerCase(Locale.ENGLISH);
Optional<Field> field = constructField(parameters.get(i), lookupColumnByName(groupColumnIO, name));
structHasParameters |= field.isPresent();
fieldsBuilder.add(field);
return Optional.empty();
Optional<Field> keyField = constructField(mapType.getKeyType(), keyValueColumnIO.getChild(0));
Optional<Field> valueField = constructField(mapType.getValueType(), keyValueColumnIO.getChild(1));
return Optional.of(new GroupField(type, repetitionLevel, definitionLevel, required, ImmutableList.of(keyField, valueField)));
return Optional.empty();
Optional<Field> field = constructField(types.get(0), getArrayElementColumn(groupColumnIO.getChild(0)));
return Optional.of(new GroupField(type, repetitionLevel, definitionLevel, required, ImmutableList.of(field)));