Package org.apache.hadoop.hbase.regionserver

Class SnapshotSegmentScanner

java.lang.Object

org.apache.hadoop.hbase.regionserver.NonLazyKeyValueScanner

org.apache.hadoop.hbase.regionserver.NonReversedNonLazyKeyValueScanner

org.apache.hadoop.hbase.regionserver.SnapshotSegmentScanner

All Implemented Interfaces:

Closeable, AutoCloseable, KeyValueScanner, Shipper

@Private
public class SnapshotSegmentScanner
extends NonReversedNonLazyKeyValueScanner

A basic SegmentScanner used against an ImmutableScanner snapshot Used flushing where we do a single pass, no reverse scanning or inserts happening. Its a dumbed-down Scanner that can go fast. Like CollectionBackedScanner (but making it know about Segments was onerous).

Field Summary

Fields

Modifier and Type	Field	Description
private ExtendedCell	current
private Iterator<ExtendedCell>	iter
private final ImmutableSegment	segment

Fields inherited from interface org.apache.hadoop.hbase.regionserver.KeyValueScanner

NO_NEXT_INDEXED_KEY

Constructor Summary

Constructors

Constructor	Description
SnapshotSegmentScanner(ImmutableSegment segment)

Method Summary

Modifier and Type	Method	Description
void	close()	Close the KeyValue scanner.
private static Iterator<ExtendedCell>	createIterator(Segment segment)
long	getScannerOrder()	Get the order of this KeyValueScanner.
ExtendedCell	next()	Return the next Cell in this scanner, iterating the scanner
ExtendedCell	peek()	Look at the next Cell in this scanner, but do not iterate scanner.
boolean	reseek(ExtendedCell seekCell)	Reseek the scanner at or after the specified KeyValue.
boolean	seek(ExtendedCell seekCell)	Seek the scanner at or after the specified KeyValue.

Methods inherited from class org.apache.hadoop.hbase.regionserver.NonReversedNonLazyKeyValueScanner

backwardSeek, seekToLastRow, seekToPreviousRow

Methods inherited from class org.apache.hadoop.hbase.regionserver.NonLazyKeyValueScanner

doRealSeek, enforceSeek, getFilePath, getNextIndexedKey, isFileScanner, realSeekDone, recordBlockSize, requestSeek, shipped, shouldUseScanner

Methods inherited from class java.lang.Object

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

Field Details

segment

private final ImmutableSegment segment

iter

private Iterator<ExtendedCell> iter

current

private ExtendedCell current

Constructor Details

SnapshotSegmentScanner

public SnapshotSegmentScanner(ImmutableSegment segment)

Method Details

createIterator

private static Iterator<ExtendedCell> createIterator(Segment segment)

peek

public ExtendedCell peek()

Description copied from interface: KeyValueScanner

Look at the next Cell in this scanner, but do not iterate scanner. NOTICE: The returned cell has not been passed into ScanQueryMatcher. So it may not be what the user need.

Returns:

the next Cell

next

public ExtendedCell next()

Description copied from interface: KeyValueScanner

Return the next Cell in this scanner, iterating the scanner

Returns:

the next Cell

seek

public boolean seek(ExtendedCell seekCell)

Description copied from interface: KeyValueScanner

Seek the scanner at or after the specified KeyValue.

Parameters:

seekCell - seek value

Returns:

true if scanner has values left, false if end of scanner

reseek

public boolean reseek(ExtendedCell seekCell)

Description copied from interface: KeyValueScanner

Reseek the scanner at or after the specified KeyValue. This method is guaranteed to seek at or after the required key only if the key comes after the current position of the scanner. Should not be used to seek to a key which may come before the current position.

Parameters:

seekCell - seek value (should be non-null)

Returns:

true if scanner has values left, false if end of scanner

getScannerOrder

public long getScannerOrder()

Description copied from interface: KeyValueScanner

Get the order of this KeyValueScanner. This is only relevant for StoreFileScanners. This is required for comparing multiple files to find out which one has the latest data. StoreFileScanners are ordered from 0 (oldest) to newest in increasing order.

See Also:

• KeyValueScanner.getScannerOrder()

close

public void close()

Description copied from interface: KeyValueScanner

Close the KeyValue scanner.