org.apache.drill.exec.vector.accessor

Interface TupleReader

All Superinterfaces:

ColumnReader

All Known Subinterfaces:

RowSetReader

All Known Implementing Classes:

AbstractTupleReader, DictEntryReader, MapReader, RowSetReaderImpl

public interface TupleReader
extends ColumnReader

Interface for reading from tuples (rows or maps). Provides a column reader for each column that can be obtained either by name or column index (as defined in the tuple schema.) Also provides two generic methods to get the value as a Java object or as a string.

See Also:

TupleWriter}

Method Summary

Modifier and Type	Method and Description
ArrayReader	array(int colIndex)
ArrayReader	array(String colName)
ObjectReader	column(int colIndex) Return a column reader by column index as reported by the associated metadata.
ObjectReader	column(String colName) Return a column reader by name.
int	columnCount()
DictReader	dict(int colIndex)
DictReader	dict(String colName)
ScalarReader	scalar(int colIndex)
ScalarReader	scalar(String colName)
TupleReader	tuple(int colIndex)
TupleReader	tuple(String colName)
TupleMetadata	tupleSchema()
ObjectType	type(int colIndex)
ObjectType	type(String colName)
VariantReader	variant(int colIndex)
VariantReader	variant(String colName)

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

getAsString, getObject, isNull, schema, type

Method Detail

tupleSchema

TupleMetadata tupleSchema()

columnCount

int columnCount()

column

ObjectReader column(int colIndex)

Return a column reader by column index as reported by the associated metadata.

Parameters:

colIndex - column index

Returns:

reader for the column

Throws:

{@link - java.lang.IndexOutOfBoundsException} if the index is invalid

column

ObjectReader column(String colName)

Return a column reader by name.

Parameters:

colName - column name

Returns:

reader for the column, or null if no such column exists

type

ObjectType type(int colIndex)

type

ObjectType type(String colName)

scalar

ScalarReader scalar(int colIndex)

scalar

ScalarReader scalar(String colName)

tuple

TupleReader tuple(int colIndex)

tuple

TupleReader tuple(String colName)

array

ArrayReader array(int colIndex)

array

ArrayReader array(String colName)

variant

VariantReader variant(int colIndex)

variant

VariantReader variant(String colName)

dict

DictReader dict(int colIndex)

dict

DictReader dict(String colName)