org.apache.drill.exec.vector.accessor

Interface ObjectReader

All Superinterfaces:

ColumnReader

All Known Implementing Classes:

AbstractObjectReader, AbstractScalarReader.ScalarObjectReader, AbstractTupleReader.TupleObjectReader, ArrayReaderImpl.ArrayObjectReader, DictReaderImpl.DictObjectReader, UnionReaderImpl.UnionObjectReader

public interface ObjectReader
extends ColumnReader

Defines a reader to get values for value vectors using a simple, uniform interface modeled after a JSON object. Every column value is an object of one of three types: scalar, array or tuple. Methods exist to "cast" this object to the proper type. This model allows a very simple representation: tuples (rows, maps) consist of objects. Arrays are lists of objects.

{@see ObjectWriter>

Method Summary

Modifier and Type	Method and Description
ArrayReader	array()
DictReader	dict()
ColumnReader	reader() Gets the reader as a generic type, for dynamic programming.
ScalarReader	scalar()
TupleReader	tuple()
VariantReader	variant()

Methods inherited from interface org.apache.drill.exec.vector.accessor.ColumnReader

getAsString, getObject, isNull, schema, type

Method Detail

scalar

ScalarReader scalar()

tuple

TupleReader tuple()

array

ArrayReader array()

variant

VariantReader variant()

dict

DictReader dict()

reader

ColumnReader reader()

Gets the reader as a generic type, for dynamic programming.

Returns:

the untyped reader