Package org.apache.hadoop.hdfs.server.common.blockaliasmap.impl

Class LevelDBFileRegionAliasMap

java.lang.Object

org.apache.hadoop.hdfs.server.common.blockaliasmap.BlockAliasMap<FileRegion>

org.apache.hadoop.hdfs.server.common.blockaliasmap.impl.LevelDBFileRegionAliasMap

All Implemented Interfaces:

org.apache.hadoop.conf.Configurable

@Public
@Unstable
public class LevelDBFileRegionAliasMap
extends BlockAliasMap<FileRegion>
implements org.apache.hadoop.conf.Configurable

A LevelDB based implementation of BlockAliasMap.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	LevelDBFileRegionAliasMap.LevelDBOptions	Class specifying reader options for the LevelDBFileRegionAliasMap.
static class	LevelDBFileRegionAliasMap.LevelDBReader	This class is used as a reader for block maps which are stored as LevelDB files.
static class	LevelDBFileRegionAliasMap.LevelDBWriter	This class is used as a writer for block maps which are stored as LevelDB files.

Nested classes/interfaces inherited from class org.apache.hadoop.hdfs.server.common.blockaliasmap.BlockAliasMap

BlockAliasMap.ImmutableIterator, BlockAliasMap.Reader<U extends BlockAlias>, BlockAliasMap.Writer<U extends BlockAlias>

Field Summary

Fields

Modifier and Type	Field	Description
static final org.slf4j.Logger	LOG

Constructor Summary

Constructors

Constructor	Description
LevelDBFileRegionAliasMap()

Method Summary

Modifier and Type	Method	Description
void	close()
org.apache.hadoop.conf.Configuration	getConf()
BlockAliasMap.Reader<FileRegion>	getReader(BlockAliasMap.Reader.Options opts, String blockPoolID)	Returns a reader to the alias map.
BlockAliasMap.Writer<FileRegion>	getWriter(BlockAliasMap.Writer.Options opts, String blockPoolID)	Returns the writer for the alias map.
void	refresh()	Refresh the alias map.
void	setConf(org.apache.hadoop.conf.Configuration conf)

Methods inherited from class java.lang.Object

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

Field Details

LOG

public static final org.slf4j.Logger LOG

Constructor Details

LevelDBFileRegionAliasMap

public LevelDBFileRegionAliasMap()

Method Details

setConf

public void setConf(org.apache.hadoop.conf.Configuration conf)

Specified by:

setConf in interface org.apache.hadoop.conf.Configurable

getConf

public org.apache.hadoop.conf.Configuration getConf()

Specified by:

getConf in interface org.apache.hadoop.conf.Configurable

getReader

public BlockAliasMap.Reader<FileRegion> getReader(BlockAliasMap.Reader.Options opts,
 String blockPoolID)
                                           throws IOException

Description copied from class: BlockAliasMap

Returns a reader to the alias map.

Specified by:

getReader in class BlockAliasMap<FileRegion>

Parameters:

opts - reader options

blockPoolID - block pool id to use

Returns:

BlockAliasMap.Reader to the alias map. If a Reader for the blockPoolID cannot be created, this will return null.

Throws:

IOException

getWriter

public BlockAliasMap.Writer<FileRegion> getWriter(BlockAliasMap.Writer.Options opts,
 String blockPoolID)
                                           throws IOException

Description copied from class: BlockAliasMap

Returns the writer for the alias map.

Specified by:

getWriter in class BlockAliasMap<FileRegion>

Parameters:

opts - writer options.

blockPoolID - block pool id to use

Returns:

BlockAliasMap.Writer to the alias map.

Throws:

IOException

refresh

public void refresh()
             throws IOException

Description copied from class: BlockAliasMap

Refresh the alias map.

Specified by:

refresh in class BlockAliasMap<FileRegion>

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in class BlockAliasMap<FileRegion>

Throws:

IOException