Package org.iq80.leveldb.table

Class BlockIterator

java.lang.Object

org.iq80.leveldb.table.BlockIterator

All Implemented Interfaces:

com.google.common.collect.PeekingIterator<Map.Entry<Slice,Slice>>, Iterator<Map.Entry<Slice,Slice>>, SeekingIterator<Slice,Slice>

public class BlockIterator
extends Object
implements SeekingIterator<Slice,Slice>

Field Summary

Fields

Modifier and Type	Field	Description
private final Comparator<Slice>	comparator
private final SliceInput	data
private BlockEntry	nextEntry
private final int	restartCount
private final Slice	restartPositions

Constructor Summary

Constructors

Constructor	Description
BlockIterator(Slice data, Slice restartPositions, Comparator<Slice> comparator)

Method Summary

Modifier and Type	Method	Description
boolean	hasNext()
BlockEntry	next()
BlockEntry	peek()
private static BlockEntry	readEntry(SliceInput data, BlockEntry previousEntry)	Reads the entry at the current data readIndex.
void	remove()
void	seek(Slice targetKey)	Repositions the iterator so the key of the next BlockElement returned greater than or equal to the specified targetKey.
void	seekToFirst()	Repositions the iterator so the beginning of this block.
private void	seekToRestartPosition(int restartPosition)	Seeks to and reads the entry at the specified restart position.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining

Field Details

data

private final SliceInput data

restartPositions

private final Slice restartPositions

restartCount

private final int restartCount

comparator

private final Comparator<Slice> comparator

nextEntry

private BlockEntry nextEntry

Constructor Details

BlockIterator

public BlockIterator(Slice data,
 Slice restartPositions,
 Comparator<Slice> comparator)

Method Details

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<Map.Entry<Slice,Slice>>

peek

public BlockEntry peek()

Specified by:

peek in interface com.google.common.collect.PeekingIterator<Map.Entry<Slice,Slice>>

next

public BlockEntry next()

Specified by:

next in interface Iterator<Map.Entry<Slice,Slice>>

Specified by:

next in interface com.google.common.collect.PeekingIterator<Map.Entry<Slice,Slice>>

remove

public void remove()

Specified by:

remove in interface Iterator<Map.Entry<Slice,Slice>>

Specified by:

remove in interface com.google.common.collect.PeekingIterator<Map.Entry<Slice,Slice>>

seekToFirst

public void seekToFirst()

Repositions the iterator so the beginning of this block.

Specified by:

seekToFirst in interface SeekingIterator<Slice,Slice>

seek

public void seek(Slice targetKey)

Repositions the iterator so the key of the next BlockElement returned greater than or equal to the specified targetKey.

Specified by:

seek in interface SeekingIterator<Slice,Slice>

seekToRestartPosition

private void seekToRestartPosition(int restartPosition)

Seeks to and reads the entry at the specified restart position.

After this method, nextEntry will contain the next entry to return, and the previousEntry will be null.

readEntry

private static BlockEntry readEntry(SliceInput data,
 BlockEntry previousEntry)

Reads the entry at the current data readIndex. After this method, data readIndex is positioned at the beginning of the next entry or at the end of data if there was not a next entry.

Returns:

true if an entry was read