org.apache.hadoop.hbase.codec.prefixtree

Class PrefixTreeSeeker

java.lang.Object

org.apache.hadoop.hbase.codec.prefixtree.PrefixTreeSeeker

All Implemented Interfaces:

DataBlockEncoder.EncodedSeeker

@InterfaceAudience.Private
public class PrefixTreeSeeker
extends Object
implements DataBlockEncoder.EncodedSeeker

These methods have the same definition as any implementation of the EncodedSeeker. In the future, the EncodedSeeker could be modified to work with the Cell interface directly. It currently returns a new KeyValue object each time getKeyValue is called. This is not horrible, but in order to create a new KeyValue object, we must first allocate a new byte[] and copy in the data from the PrefixTreeCell. It is somewhat heavyweight right now.

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	includeMvccVersion
protected PrefixTreeArraySearcher	ptSearcher

Constructor Summary

Constructors

Constructor and Description
PrefixTreeSeeker(boolean includeMvccVersion)

Method Summary

Modifier and Type	Method and Description
boolean	advance()
int	compareKey(CellComparator comparator, Cell key)
Cell	get() Currently unused.
Cell	getCell() currently must do deep copy into new array
Cell	getKey()
ByteBuffer	getValueShallowCopy()
boolean	next()
void	releaseCurrentSearcher() Currently unused.
void	rewind()
int	seekToKeyInBlock(Cell key, boolean forceBeforeOnExactMatch)
protected int	seekToOrBeforeUsingPositionAtOrAfter(Cell kv, boolean seekBefore)
protected int	seekToOrBeforeUsingPositionAtOrBefore(Cell kv, boolean seekBefore)
void	setCurrentBuffer(ByteBuff fullBlockBuffer)

Methods inherited from class java.lang.Object

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

Field Detail

includeMvccVersion

protected boolean includeMvccVersion

ptSearcher

protected PrefixTreeArraySearcher ptSearcher

Constructor Detail

PrefixTreeSeeker

public PrefixTreeSeeker(boolean includeMvccVersion)

Method Detail

setCurrentBuffer

public void setCurrentBuffer(ByteBuff fullBlockBuffer)

Specified by:

setCurrentBuffer in interface DataBlockEncoder.EncodedSeeker

releaseCurrentSearcher

public void releaseCurrentSearcher()

Currently unused.

TODO performance leak. should reuse the searchers. hbase does not currently have a hook where this can be called

getKey

public Cell getKey()

Specified by:

getKey in interface DataBlockEncoder.EncodedSeeker

getValueShallowCopy

public ByteBuffer getValueShallowCopy()

Specified by:

getValueShallowCopy in interface DataBlockEncoder.EncodedSeeker

getCell

public Cell getCell()

currently must do deep copy into new array

Specified by:

getCell in interface DataBlockEncoder.EncodedSeeker

get

public Cell get()

Currently unused.

A nice, lightweight reference, though the underlying cell is transient. This method may return the same reference to the backing PrefixTreeCell repeatedly, while other implementations may return a different reference for each Cell.

The goal will be to transition the upper layers of HBase, like Filters and KeyValueHeap, to use this method instead of the getKeyValue() methods above.

rewind

public void rewind()

Specified by:

rewind in interface DataBlockEncoder.EncodedSeeker

next

public boolean next()

Specified by:

next in interface DataBlockEncoder.EncodedSeeker

advance

public boolean advance()

seekToOrBeforeUsingPositionAtOrBefore

protected int seekToOrBeforeUsingPositionAtOrBefore(Cell kv,
                                                    boolean seekBefore)

seekToOrBeforeUsingPositionAtOrAfter

protected int seekToOrBeforeUsingPositionAtOrAfter(Cell kv,
                                                   boolean seekBefore)

seekToKeyInBlock

public int seekToKeyInBlock(Cell key,
                            boolean forceBeforeOnExactMatch)

Specified by:

seekToKeyInBlock in interface DataBlockEncoder.EncodedSeeker

compareKey

public int compareKey(CellComparator comparator,
                      Cell key)

Specified by:

compareKey in interface DataBlockEncoder.EncodedSeeker