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

Class StaticColumnLoader

java.lang.Object

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

Direct Known Subclasses:

ConstantColumnLoader, NullColumnLoader

public abstract class StaticColumnLoader
extends Object

Base class for columns that take values based on the reader, not individual rows. E.g. null columns (values are all null) or file metadata (AKA "implicit") columns that take values based on the file.

Field Summary

Fields

Modifier and Type	Field	Description
protected final ResultSetLoader	loader
protected final ResultVectorCache	vectorCache

Constructor Summary

Constructors

Constructor	Description
StaticColumnLoader(ResultVectorCache vectorCache)

Method Summary

Modifier and Type	Method	Description
void	close()
abstract VectorContainer	load(int rowCount)	Populate static vectors with the defined static values.

Methods inherited from class java.lang.Object

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

Field Details

loader

protected final ResultSetLoader loader

vectorCache

protected final ResultVectorCache vectorCache

Constructor Details

StaticColumnLoader

public StaticColumnLoader(ResultVectorCache vectorCache)

Method Details

load

public abstract VectorContainer load(int rowCount)

Populate static vectors with the defined static values.

Parameters:

rowCount - number of rows to generate. Must match the row count in the batch returned by the reader

close

public void close()