org.apache.hadoop.hbase.regionserver.querymatcher

Class NewVersionBehaviorTracker

java.lang.Object

org.apache.hadoop.hbase.regionserver.querymatcher.NewVersionBehaviorTracker

All Implemented Interfaces:

ColumnTracker, DeleteTracker, ShipperListener

Direct Known Subclasses:

VisibilityNewVersionBehaivorTracker

@InterfaceAudience.Private
public class NewVersionBehaviorTracker
extends Object
implements ColumnTracker, DeleteTracker

A tracker both implementing ColumnTracker and DeleteTracker, used for mvcc-sensitive scanning. We should make sure in one QueryMatcher the ColumnTracker and DeleteTracker is the same instance.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	NewVersionBehaviorTracker.DeleteVersionsNode A data structure which contains infos we need that happens before this node's mvcc and after the previous node's mvcc.

Nested classes/interfaces inherited from interface org.apache.hadoop.hbase.regionserver.querymatcher.DeleteTracker

DeleteTracker.DeleteResult

Field Summary

Fields

Modifier and Type	Field and Description
private int	columnIndex
private byte[][]	columns
private CellComparator	comparator
private int	countCurrentCol
protected NavigableMap<Long,NewVersionBehaviorTracker.DeleteVersionsNode>	delColMap
protected NavigableMap<Long,NewVersionBehaviorTracker.DeleteVersionsNode>	delFamMap
private byte[]	lastCqArray
private int	lastCqLength
private long	lastCqMvcc
private int	lastCqOffset
private long	lastCqTs
private byte	lastCqType
protected int	maxVersions
private int	minVersions
private long	oldestStamp
private int	resultMaxVersions

Constructor Summary

Constructors

Constructor and Description
NewVersionBehaviorTracker(NavigableSet<byte[]> columns, CellComparator comparartor, int minVersion, int maxVersion, int resultMaxVersions, long oldestUnexpiredTS) Note maxVersion and minVersion must set according to cf's conf, not user's scan parameter.

Method Summary

Modifier and Type	Method and Description
void	add(Cell cell) Add the specified cell to the list of deletes to check against for this row operation.
void	beforeShipped() The action that needs to be performed before Shipper.shipped() is performed
ScanQueryMatcher.MatchCode	checkColumn(Cell cell, byte type) Checks if the column is present in the list of requested columns by returning the match code instance.
ScanQueryMatcher.MatchCode	checkVersions(Cell cell, long timestamp, byte type, boolean ignoreCount) Keeps track of the number of versions for the columns asked for.
boolean	done()
CellComparator	getCellComparator() Return the comparator passed to this delete tracker
ColumnCount	getColumnHint() Used by matcher and scan/get to get a hint of the next column to seek to after checkColumn() returns SKIP.
ScanQueryMatcher.MatchCode	getNextRowOrNextColumn(Cell cell) Retrieve the MatchCode for the next row or column
DeleteTracker.DeleteResult	isDeleted(Cell cell) This method is not idempotent, we will save some info to judge VERSION_MASKED.
boolean	isDone(long timestamp) Give the tracker a chance to declare it's done based on only the timestamp to allow an early out.
boolean	isEmpty()
protected long	prepare(Cell cell) Reset the map if it is different with the last Cell.
void	reset() Resets the Matcher
protected void	resetInternal()
void	update() Called at the end of every StoreFile.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.hbase.regionserver.querymatcher.ColumnTracker

doneWithColumn

Field Detail

lastCqArray

private byte[] lastCqArray

lastCqLength

private int lastCqLength

lastCqOffset

private int lastCqOffset

lastCqTs

private long lastCqTs

lastCqMvcc

private long lastCqMvcc

lastCqType

private byte lastCqType

columnIndex

private int columnIndex

countCurrentCol

private int countCurrentCol

maxVersions

protected int maxVersions

resultMaxVersions

private int resultMaxVersions

columns

private byte[][] columns

minVersions

private int minVersions

oldestStamp

private long oldestStamp

comparator

private CellComparator comparator

delColMap

protected NavigableMap<Long,NewVersionBehaviorTracker.DeleteVersionsNode> delColMap

delFamMap

protected NavigableMap<Long,NewVersionBehaviorTracker.DeleteVersionsNode> delFamMap

Constructor Detail

NewVersionBehaviorTracker

public NewVersionBehaviorTracker(NavigableSet<byte[]> columns,
                                 CellComparator comparartor,
                                 int minVersion,
                                 int maxVersion,
                                 int resultMaxVersions,
                                 long oldestUnexpiredTS)

Note maxVersion and minVersion must set according to cf's conf, not user's scan parameter.

Parameters:

columns - columns specified user in query

comparartor - the cell comparator

minVersion - The minimum number of versions to keep(used when TTL is set).

maxVersion - The maximum number of versions in CF's conf

resultMaxVersions - maximum versions to return per column, which may be different from maxVersion

oldestUnexpiredTS - the oldest timestamp we are interested in, based on TTL

Method Detail

beforeShipped

public void beforeShipped()
                   throws IOException

Description copied from interface: ShipperListener

The action that needs to be performed before Shipper.shipped() is performed

Specified by:

beforeShipped in interface ShipperListener

Throws:

IOException

prepare

protected long prepare(Cell cell)

Reset the map if it is different with the last Cell. Save the cq array/offset/length for next Cell.

Returns:

If this put has duplicate ts with last cell, return the mvcc of last cell. Else return MAX_VALUE.

add

public void add(Cell cell)

Description copied from interface: DeleteTracker

Add the specified cell to the list of deletes to check against for this row operation.

This is called when a Delete is encountered in a StoreFile.

Specified by:

add in interface DeleteTracker

Parameters:

cell - - the delete cell

isDeleted

public DeleteTracker.DeleteResult isDeleted(Cell cell)

This method is not idempotent, we will save some info to judge VERSION_MASKED.

Specified by:

isDeleted in interface DeleteTracker

Parameters:

cell - - current cell to check if deleted by a previously seen delete

Returns:

We don't distinguish DeleteColumn and DeleteFamily. We only return code for column.

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface DeleteTracker

Returns:

true if there are no current delete, false otherwise

update

public void update()

Description copied from interface: DeleteTracker

Called at the end of every StoreFile.

Many optimized implementations of Trackers will require an update at when the end of each StoreFile is reached.

Specified by:

update in interface DeleteTracker

checkColumn

public ScanQueryMatcher.MatchCode checkColumn(Cell cell,
                                              byte type)
                                       throws IOException

Description copied from interface: ColumnTracker

Checks if the column is present in the list of requested columns by returning the match code instance. It does not check against the number of versions for the columns asked for. To do the version check, one has to call ColumnTracker.checkVersions(Cell, long, byte, boolean) method based on the return type (INCLUDE) of this method. The values that can be returned by this method are ScanQueryMatcher.MatchCode.INCLUDE, ScanQueryMatcher.MatchCode.SEEK_NEXT_COL and ScanQueryMatcher.MatchCode.SEEK_NEXT_ROW.

Specified by:

checkColumn in interface ColumnTracker

type - The type of the Cell

Returns:

The match code instance.

Throws:

IOException - in case there is an internal consistency problem caused by a data corruption.

checkVersions

public ScanQueryMatcher.MatchCode checkVersions(Cell cell,
                                                long timestamp,
                                                byte type,
                                                boolean ignoreCount)
                                         throws IOException

Description copied from interface: ColumnTracker

Keeps track of the number of versions for the columns asked for. It assumes that the user has already checked if the cell needs to be included by calling the ColumnTracker.checkColumn(Cell, byte) method. The enum values returned by this method are ScanQueryMatcher.MatchCode.SKIP, ScanQueryMatcher.MatchCode.INCLUDE, ScanQueryMatcher.MatchCode.INCLUDE_AND_SEEK_NEXT_COL and ScanQueryMatcher.MatchCode.INCLUDE_AND_SEEK_NEXT_ROW. Implementations which include all the columns could just return ScanQueryMatcher.MatchCode.INCLUDE in the ColumnTracker.checkColumn(Cell, byte) method and perform all the operations in this checkVersions method.

Specified by:

checkVersions in interface ColumnTracker

timestamp - The timestamp of the cell.

type - the type of the key value (Put/Delete)

ignoreCount - indicates if the KV needs to be excluded while counting (used during compactions. We only count KV's that are older than all the scanners' read points.)

Returns:

the scan query matcher match code instance

Throws:

IOException - in case there is an internal consistency problem caused by a data corruption.

reset

public void reset()

Description copied from interface: ColumnTracker

Resets the Matcher

Specified by:

reset in interface ColumnTracker

Specified by:

reset in interface DeleteTracker

resetInternal

protected void resetInternal()

done

public boolean done()

Specified by:

done in interface ColumnTracker

Returns:

true when done.

getColumnHint

public ColumnCount getColumnHint()

Description copied from interface: ColumnTracker

Used by matcher and scan/get to get a hint of the next column to seek to after checkColumn() returns SKIP. Returns the next interesting column we want, or NULL there is none (wildcard scanner). Implementations aren't required to return anything useful unless the most recent call was to checkColumn() and the return code was SKIP. This is pretty implementation detail-y, but optimizations are like that.

Specified by:

getColumnHint in interface ColumnTracker

Returns:

null, or a ColumnCount that we should seek to

getNextRowOrNextColumn

public ScanQueryMatcher.MatchCode getNextRowOrNextColumn(Cell cell)

Description copied from interface: ColumnTracker

Retrieve the MatchCode for the next row or column

Specified by:

getNextRowOrNextColumn in interface ColumnTracker

isDone

public boolean isDone(long timestamp)

Description copied from interface: ColumnTracker

Give the tracker a chance to declare it's done based on only the timestamp to allow an early out.

Specified by:

isDone in interface ColumnTracker

Returns:

true to early out based on timestamp.

getCellComparator

public CellComparator getCellComparator()

Description copied from interface: DeleteTracker

Return the comparator passed to this delete tracker

Specified by:

getCellComparator in interface DeleteTracker

Returns:

the cell comparator