org.apache.hadoop.hdfs.server.aliasmap

Class InMemoryAliasMap

java.lang.Object

org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMap

All Implemented Interfaces:

Configurable, org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

@InterfaceAudience.Public
 @InterfaceStability.Unstable
public class InMemoryAliasMap
extends Object
implements org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol, Configurable

InMemoryAliasMap is an implementation of the InMemoryAliasMapProtocol for use with LevelDB.

Method Summary

Modifier and Type	Method and Description
void	close()
static void	completeBootstrapTransfer(File aliasMap) Extract the aliasmap archive to complete the bootstrap process.
static org.apache.hadoop.hdfs.protocol.Block	fromBlockBytes(byte[] blockDbFormat)
static org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation	fromProvidedStorageLocationBytes(byte[] providedStorageLocationDbFormat)
String	getBlockPoolId() Get the associated block pool id.
Configuration	getConf() Return the configuration used by this object.
static InMemoryAliasMap	init(Configuration conf, String blockPoolID)
org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol.IterationResult	list(Optional<org.apache.hadoop.hdfs.protocol.Block> marker) List the next batch of FileRegions in the alias map starting from the given marker.
Optional<org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation>	read(org.apache.hadoop.hdfs.protocol.Block block) Gets the ProvidedStorageLocation associated with the specified block.
void	setConf(Configuration conf) Set the configuration to be used by this object.
static byte[]	toProtoBufBytes(org.apache.hadoop.hdfs.protocol.Block block)
static byte[]	toProtoBufBytes(org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation providedStorageLocation)
static void	transferForBootstrap(javax.servlet.http.HttpServletResponse response, Configuration conf, InMemoryAliasMap aliasMap) Transfer this aliasmap for bootstrapping standby Namenodes.
void	write(org.apache.hadoop.hdfs.protocol.Block block, org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation providedStorageLocation) Stores the block and it's associated ProvidedStorageLocation in the alias map.

Methods inherited from class java.lang.Object

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

Method Detail

setConf

public void setConf(Configuration conf)

Description copied from interface: Configurable

Set the configuration to be used by this object.

Specified by:

setConf in interface Configurable

Parameters:

conf - configuration to be used

getConf

public Configuration getConf()

Description copied from interface: Configurable

Return the configuration used by this object.

Specified by:

getConf in interface Configurable

Returns:

Configuration

init

@Nonnull
public static InMemoryAliasMap init(Configuration conf,
                                             String blockPoolID)
                                      throws IOException

Throws:

IOException

list

public org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol.IterationResult list(Optional<org.apache.hadoop.hdfs.protocol.Block> marker)
                                                                                     throws IOException

Description copied from interface: org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

List the next batch of FileRegions in the alias map starting from the given marker. To retrieve all FileRegions stored in the alias map, multiple calls to this function might be required.

Specified by:

list in interface org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

Parameters:

marker - the next block to get fileregions from.

Returns:

the InMemoryAliasMapProtocol.IterationResult with a set of FileRegions and the next marker.

Throws:

IOException

read

@Nonnull
public Optional<org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation> read(@Nonnull
                                                                                       org.apache.hadoop.hdfs.protocol.Block block)
                                                                                throws IOException

Description copied from interface: org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

Gets the ProvidedStorageLocation associated with the specified block.

Specified by:

read in interface org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

Parameters:

block - the block to lookup

Returns:

the associated ProvidedStorageLocation.

Throws:

IOException

write

public void write(@Nonnull
                  org.apache.hadoop.hdfs.protocol.Block block,
                  @Nonnull
                  org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation providedStorageLocation)
           throws IOException

Description copied from interface: org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

Stores the block and it's associated ProvidedStorageLocation in the alias map.

Specified by:

write in interface org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

Throws:

IOException

getBlockPoolId

public String getBlockPoolId()

Description copied from interface: org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

Get the associated block pool id.

Specified by:

getBlockPoolId in interface org.apache.hadoop.hdfs.server.aliasmap.InMemoryAliasMapProtocol

Returns:

the block pool id associated with the Namenode running the in-memory alias map.

close

public void close()
           throws IOException

Throws:

IOException

fromProvidedStorageLocationBytes

@Nonnull
public static org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation fromProvidedStorageLocationBytes(@Nonnull
                                                                                                                byte[] providedStorageLocationDbFormat)
                                                                                                         throws com.google.protobuf.InvalidProtocolBufferException

Throws:

com.google.protobuf.InvalidProtocolBufferException

fromBlockBytes

@Nonnull
public static org.apache.hadoop.hdfs.protocol.Block fromBlockBytes(@Nonnull
                                                                            byte[] blockDbFormat)
                                                                     throws com.google.protobuf.InvalidProtocolBufferException

Throws:

com.google.protobuf.InvalidProtocolBufferException

toProtoBufBytes

public static byte[] toProtoBufBytes(@Nonnull
                                     org.apache.hadoop.hdfs.protocol.ProvidedStorageLocation providedStorageLocation)
                              throws IOException

Throws:

IOException

toProtoBufBytes

public static byte[] toProtoBufBytes(@Nonnull
                                     org.apache.hadoop.hdfs.protocol.Block block)
                              throws IOException

Throws:

IOException

transferForBootstrap

public static void transferForBootstrap(javax.servlet.http.HttpServletResponse response,
                                        Configuration conf,
                                        InMemoryAliasMap aliasMap)
                                 throws IOException

Transfer this aliasmap for bootstrapping standby Namenodes. The map is transferred as a tar.gz archive. This archive needs to be extracted on the standby Namenode.

Parameters:

response - http response.

conf - configuration to use.

aliasMap - aliasmap to transfer.

Throws:

IOException

completeBootstrapTransfer

public static void completeBootstrapTransfer(File aliasMap)
                                      throws IOException

Extract the aliasmap archive to complete the bootstrap process. This method has to be called after the aliasmap archive is transfered from the primary Namenode.

Parameters:

aliasMap - location of the aliasmap.

Throws:

IOException