com.facebook.presto.common

Class Page

java.lang.Object

com.facebook.presto.common.Page

public final class Page
extends Object

Field Summary

Fields

Modifier and Type	Field and Description
static int	INSTANCE_SIZE

Constructor Summary

Constructors

Constructor and Description
Page(Block... blocks)
Page(int positionCount)
Page(int positionCount, Block... blocks)

Method Summary

Modifier and Type	Method and Description
Page	appendColumn(Block block)
Page	compact()
Page	copyPositions(int[] retainedPositions, int offset, int length)
Page	dropColumn(int channelIndex)
Page	extractChannel(int channel)
Page	extractChannels(int[] channels)
long	getApproximateLogicalSizeInBytes() Returns the approximate logical size of the page if logicalSizeInBytes was not calculated before.
Block	getBlock(int channel)
int	getChannelCount()
Page	getLoadedPage() Returns a page that assures all data is in memory.
Page	getLoadedPage(int... channels)
Page	getLoadedPage(int channel)
long	getLogicalSizeInBytes()
int	getPositionCount()
Page	getPositions(int[] retainedPositions, int offset, int length)
Page	getRegion(int positionOffset, int length)
long	getRetainedSizeInBytes()
Page	getSingleValuePage(int position) Gets the values at the specified position as a single element page.
long	getSizeInBytes()
Page	prependColumn(Block column)
String	toString()
static Page	wrapBlocksWithoutCopy(int positionCount, Block[] blocks) Visible to give trusted classes like PageBuilder access to a constructor that doesn't defensively copy the blocks

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE_SIZE

public static final int INSTANCE_SIZE

Constructor Detail

Page

public Page(Block... blocks)

Page

public Page(int positionCount)

Page

public Page(int positionCount,
            Block... blocks)

Method Detail

wrapBlocksWithoutCopy

public static Page wrapBlocksWithoutCopy(int positionCount,
                                         Block[] blocks)

Visible to give trusted classes like PageBuilder access to a constructor that doesn't defensively copy the blocks

getChannelCount

public int getChannelCount()

getPositionCount

public int getPositionCount()

getSizeInBytes

public long getSizeInBytes()

getLogicalSizeInBytes

public long getLogicalSizeInBytes()

getApproximateLogicalSizeInBytes

public long getApproximateLogicalSizeInBytes()

Returns the approximate logical size of the page if logicalSizeInBytes was not calculated before.

getRetainedSizeInBytes

public long getRetainedSizeInBytes()

getBlock

public Block getBlock(int channel)

getSingleValuePage

public Page getSingleValuePage(int position)

Gets the values at the specified position as a single element page. The method creates independent copy of the data.

getRegion

public Page getRegion(int positionOffset,
                      int length)

appendColumn

public Page appendColumn(Block block)

compact

public Page compact()

getLoadedPage

public Page getLoadedPage()

Returns a page that assures all data is in memory. May return the same page if all page data is already in memory.

This allows streaming data sources to skip sections that are not accessed in a query.

getLoadedPage

public Page getLoadedPage(int channel)

getLoadedPage

public Page getLoadedPage(int... channels)

toString

public String toString()

Overrides:

toString in class Object

getPositions

public Page getPositions(int[] retainedPositions,
                         int offset,
                         int length)

copyPositions

public Page copyPositions(int[] retainedPositions,
                          int offset,
                          int length)

extractChannel

public Page extractChannel(int channel)

extractChannels

public Page extractChannels(int[] channels)

prependColumn

public Page prependColumn(Block column)

dropColumn

public Page dropColumn(int channelIndex)