Package org.apache.drill.exec.physical.impl.scan.project

Class NullColumnBuilder

java.lang.Object

org.apache.drill.exec.physical.impl.scan.project.NullColumnBuilder

All Implemented Interfaces:

VectorSource

public class NullColumnBuilder
extends Object
implements VectorSource

Manages null columns by creating a null column loader for each set of non-empty null columns. This class acts as a scan-wide facade around the per-schema null column loader.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	NullColumnBuilder.NullBuilderBuilder

Field Summary

Fields

Modifier and Type	Field	Description
protected final List<NullColumnLoader.NullColumnSpec>	nullCols	Creates null columns if needed.
protected TupleMetadata	outputSchema

Constructor Summary

Constructors

Constructor	Description
NullColumnBuilder(NullColumnBuilder.NullBuilderBuilder builder)

Method Summary

Modifier and Type	Method	Description
ResolvedNullColumn	add(String name)
ResolvedNullColumn	add(String name, TypeProtos.MajorType type)
ResolvedNullColumn	add(ColumnMetadata colDefn)
void	build(ResultVectorCache vectorCache)
void	close()
boolean	hasColumns()
void	load(int rowCount)
NullColumnBuilder	newChild(String mapName)
VectorContainer	output()
ValueVector	vector(int index)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

nullCols

protected final List<NullColumnLoader.NullColumnSpec> nullCols

Creates null columns if needed.

outputSchema

protected TupleMetadata outputSchema

Constructor Details

NullColumnBuilder

public NullColumnBuilder(NullColumnBuilder.NullBuilderBuilder builder)

Method Details

newChild

public NullColumnBuilder newChild(String mapName)

add

public ResolvedNullColumn add(String name)

add

public ResolvedNullColumn add(ColumnMetadata colDefn)

add

public ResolvedNullColumn add(String name,
 TypeProtos.MajorType type)

build

public void build(ResultVectorCache vectorCache)

hasColumns

public boolean hasColumns()

load

public void load(int rowCount)

vector

public ValueVector vector(int index)

Specified by:

vector in interface VectorSource

output

public VectorContainer output()

close

public void close()