org.apache.hadoop.hbase.regionserver

Class ScanDeleteTracker

java.lang.Object

org.apache.hadoop.hbase.regionserver.ScanDeleteTracker

All Implemented Interfaces:

DeleteTracker

@InterfaceAudience.Private
public class ScanDeleteTracker
extends Object
implements DeleteTracker

This class is responsible for the tracking and enforcement of Deletes during the course of a Scan operation. It only has to enforce Delete and DeleteColumn, since the DeleteFamily is handled at a higher level.

This class is utilized through three methods:

• add(byte[], int, int, long, byte) when encountering a Delete or DeleteColumn
• isDeleted(byte[], int, int, long) when checking if a Put KeyValue has been deleted
• update() when reaching the end of a StoreFile or row for scans

  This class is NOT thread-safe as queries are never multi-threaded

Nested Class Summary

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

DeleteTracker.DeleteCompare, DeleteTracker.DeleteResult

Constructor Summary

Constructors

Constructor and Description
ScanDeleteTracker() Constructor for ScanDeleteTracker

Method Summary

Methods

Modifier and Type	Method and Description
void	add(byte[] buffer, int qualifierOffset, int qualifierLength, long timestamp, byte type) Add the specified KeyValue to the list of deletes to check against for this row operation.
DeleteTracker.DeleteResult	isDeleted(byte[] buffer, int qualifierOffset, int qualifierLength, long timestamp) Check if the specified KeyValue buffer has been deleted by a previously seen delete.
boolean	isEmpty()
void	reset() Called between rows.
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

Constructor Detail

ScanDeleteTracker

public ScanDeleteTracker()

Constructor for ScanDeleteTracker

Method Detail

add

public void add(byte[] buffer,
       int qualifierOffset,
       int qualifierLength,
       long timestamp,
       byte type)

Add the specified KeyValue 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:

buffer - KeyValue buffer

qualifierOffset - column qualifier offset

qualifierLength - column qualifier length

timestamp - timestamp

type - delete type as byte

isDeleted

public DeleteTracker.DeleteResult isDeleted(byte[] buffer,
                                   int qualifierOffset,
                                   int qualifierLength,
                                   long timestamp)

Check if the specified KeyValue buffer has been deleted by a previously seen delete.

Specified by:

isDeleted in interface DeleteTracker

Parameters:

buffer - KeyValue buffer

qualifierOffset - column qualifier offset

qualifierLength - column qualifier length

timestamp - timestamp

Returns:

deleteResult

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface DeleteTracker

Returns:

true if there are no current delete, false otherwise

reset

public void reset()

Description copied from interface: DeleteTracker

Called between rows.

This clears everything as if a new DeleteTracker was instantiated.

Specified by:

reset in interface DeleteTracker

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