Package org.apache.hadoop.hdfs.server.datanode

Class ProvidedReplica

java.lang.Object

org.apache.hadoop.hdfs.protocol.Block

org.apache.hadoop.hdfs.server.datanode.ReplicaInfo

org.apache.hadoop.hdfs.server.datanode.ProvidedReplica

All Implemented Interfaces:

Comparable<org.apache.hadoop.hdfs.protocol.Block>, Replica, org.apache.hadoop.io.Writable, org.apache.hadoop.util.LightWeightGSet.LinkedElement

Direct Known Subclasses:

FinalizedProvidedReplica

@Private
@Unstable
public abstract class ProvidedReplica
extends ReplicaInfo

This abstract class is used as a base class for provided replicas.

Field Summary

Fields

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

Fields inherited from class org.apache.hadoop.hdfs.protocol.Block

BLOCK_FILE_PREFIX, blockFilePattern, METADATA_EXTENSION, metaFilePattern, metaOrBlockFilePattern

Constructor Summary

Constructors

Constructor	Description
ProvidedReplica(long blockId, URI fileURI, long fileOffset, long blockLen, long genStamp, org.apache.hadoop.fs.PathHandle pathHandle, FsVolumeSpi volume, org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem remoteFS)	Constructor.
ProvidedReplica(long blockId, org.apache.hadoop.fs.Path pathPrefix, String pathSuffix, long fileOffset, long blockLen, long genStamp, org.apache.hadoop.fs.PathHandle pathHandle, FsVolumeSpi volume, org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem remoteFS)	Constructor.
ProvidedReplica(ProvidedReplica r)

Method Summary

Modifier and Type	Method	Description
boolean	blockDataExists()
boolean	breakHardLinksIfNeeded()
void	bumpReplicaGS(long newGS)	Bump a replica's generation stamp to a new one.
int	compareWith(FsVolumeSpi.ScanInfo info)
void	copyBlockdata(URI destination)
void	copyMetadata(URI destination)
ReplicaRecoveryInfo	createInfo()
boolean	deleteBlockData()	Used to deletes the replica's block data.
boolean	deleteMetadata()	Used to deletes the replica's metadata.
long	getBlockDataLength()
URI	getBlockURI()	Get the URI for where the data of this replica is stored.
InputStream	getDataInputStream(long seekOffset)	Returns an InputStream to the replica's data.
OutputStream	getDataOutputStream(boolean append)	Returns an OutputStream to the replica's data.
LengthInputStream	getMetadataInputStream(long offset)	Returns an InputStream to the replica's metadata.
long	getMetadataLength()
OutputStream	getMetadataOutputStream(boolean append)	Returns an OutputStream to the replica's metadata.
URI	getMetadataURI()	Get the URI for where the metadata of this replica is stored.
org.apache.hadoop.fs.Path	getPathPrefix()
String	getPathSuffix()
boolean	getPinning(org.apache.hadoop.fs.LocalFileSystem localFS)	Check whether the block was pinned.
boolean	metadataExists()
boolean	renameData(URI destURI)	Rename the data URI to that referenced by destURI.
boolean	renameMeta(URI destURI)	Rename the metadata URI to that referenced by destURI.
void	setPathHandle(org.apache.hadoop.fs.PathHandle pathHandle)
void	setPinning(org.apache.hadoop.fs.LocalFileSystem localFS)	Set a block to be pinned on this datanode so that it cannot be moved by Balancer/Mover.
void	truncateBlock(long newLength)
void	updateWithReplica(StorageLocation replicaLocation)	Update this replica with the StorageLocation found.

Methods inherited from class org.apache.hadoop.hdfs.server.datanode.ReplicaInfo

getBytesReserved, getFileIoProvider, getNext, getOriginalBytesReserved, getOriginalReplica, getRecoveryID, getStorageUuid, getVolume, isOnTransientStorage, setNext, setRecoveryID, toString

Methods inherited from class org.apache.hadoop.hdfs.protocol.Block

appendStringTo, compareTo, equals, filename2id, getBlockId, getBlockId, getBlockName, getGenerationStamp, getGenerationStamp, getNumBytes, hashCode, isBlockFilename, isMetaFilename, matchingIdAndGenStamp, metaToBlockFile, readFields, readId, set, setBlockId, setGenerationStamp, setNumBytes, toString, write, writeId

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.hadoop.hdfs.server.datanode.Replica

getBlockId, getBytesOnDisk, getGenerationStamp, getNumBytes, getState, getVisibleLength

Field Details

LOG

public static final org.slf4j.Logger LOG

Constructor Details

ProvidedReplica

public ProvidedReplica(long blockId,
 URI fileURI,
 long fileOffset,
 long blockLen,
 long genStamp,
 org.apache.hadoop.fs.PathHandle pathHandle,
 FsVolumeSpi volume,
 org.apache.hadoop.conf.Configuration conf,
 org.apache.hadoop.fs.FileSystem remoteFS)

Constructor.

Parameters:

blockId - block id

fileURI - remote URI this block is to be read from

fileOffset - the offset in the remote URI

blockLen - the length of the block

genStamp - the generation stamp of the block

volume - the volume this block belongs to

conf - the configuration

remoteFS - reference to the remote filesystem to use for this replica.

ProvidedReplica

public ProvidedReplica(long blockId,
 org.apache.hadoop.fs.Path pathPrefix,
 String pathSuffix,
 long fileOffset,
 long blockLen,
 long genStamp,
 org.apache.hadoop.fs.PathHandle pathHandle,
 FsVolumeSpi volume,
 org.apache.hadoop.conf.Configuration conf,
 org.apache.hadoop.fs.FileSystem remoteFS)

Constructor.

Parameters:

blockId - block id

pathPrefix - A prefix of the Path associated with this replica on the remote FileSystem.

pathSuffix - A suffix of the Path associated with this replica on the remote FileSystem. Resolving the pathSuffix against the pathPrefix should provide the exact Path of the data associated with this replica on the remote FileSystem.

fileOffset - the offset in the remote URI

blockLen - the length of the block

genStamp - the generation stamp of the block

volume - the volume this block belongs to

conf - the configuration

remoteFS - reference to the remote filesystem to use for this replica.

ProvidedReplica

public ProvidedReplica(ProvidedReplica r)

Method Details

getBlockURI

public URI getBlockURI()

Description copied from class: ReplicaInfo

Get the URI for where the data of this replica is stored.

Specified by:

getBlockURI in class ReplicaInfo

Returns:

URI for the location of replica data.

getPathSuffix

@VisibleForTesting
public String getPathSuffix()

getPathPrefix

@VisibleForTesting
public org.apache.hadoop.fs.Path getPathPrefix()

getDataInputStream

public InputStream getDataInputStream(long seekOffset)
                               throws IOException

Description copied from class: ReplicaInfo

Returns an InputStream to the replica's data.

Specified by:

getDataInputStream in class ReplicaInfo

Parameters:

seekOffset - the offset at which the read is started from.

Returns:

the InputStream to read the replica data.

Throws:

IOException - if an error occurs in opening a stream to the data.

getDataOutputStream

public OutputStream getDataOutputStream(boolean append)
                                 throws IOException

Description copied from class: ReplicaInfo

Returns an OutputStream to the replica's data.

Specified by:

getDataOutputStream in class ReplicaInfo

Parameters:

append - indicates if the block should be opened for append.

Returns:

the OutputStream to write to the replica.

Throws:

IOException - if an error occurs in creating an OutputStream.

getMetadataURI

public URI getMetadataURI()

Description copied from class: ReplicaInfo

Get the URI for where the metadata of this replica is stored.

Specified by:

getMetadataURI in class ReplicaInfo

Returns:

URI for the location of replica metadata.

getMetadataOutputStream

public OutputStream getMetadataOutputStream(boolean append)
                                     throws IOException

Description copied from class: ReplicaInfo

Returns an OutputStream to the replica's metadata.

Specified by:

getMetadataOutputStream in class ReplicaInfo

Parameters:

append - indicates if the block metadata should be opened for append.

Returns:

the OutputStream to write to the replica's metadata.

Throws:

IOException - if an error occurs in creating an OutputStream.

blockDataExists

public boolean blockDataExists()

Specified by:

blockDataExists in class ReplicaInfo

Returns:

true if the replica's data exists.

deleteBlockData

public boolean deleteBlockData()

Description copied from class: ReplicaInfo

Used to deletes the replica's block data.

Specified by:

deleteBlockData in class ReplicaInfo

Returns:

true if the replica's data is successfully deleted.

getBlockDataLength

public long getBlockDataLength()

Specified by:

getBlockDataLength in class ReplicaInfo

Returns:

the length of the block on storage.

getMetadataInputStream

public LengthInputStream getMetadataInputStream(long offset)
                                         throws IOException

Description copied from class: ReplicaInfo

Returns an InputStream to the replica's metadata.

Specified by:

getMetadataInputStream in class ReplicaInfo

Parameters:

offset - the offset at which the read is started from.

Returns:

the LengthInputStream to read the replica metadata.

Throws:

IOException

metadataExists

public boolean metadataExists()

Specified by:

metadataExists in class ReplicaInfo

Returns:

true if the replica's metadata exists.

deleteMetadata

public boolean deleteMetadata()

Description copied from class: ReplicaInfo

Used to deletes the replica's metadata.

Specified by:

deleteMetadata in class ReplicaInfo

Returns:

true if the replica's metadata is successfully deleted.

getMetadataLength

public long getMetadataLength()

Specified by:

getMetadataLength in class ReplicaInfo

Returns:

the length of the metadata on storage.

renameMeta

public boolean renameMeta(URI destURI)
                   throws IOException

Description copied from class: ReplicaInfo

Rename the metadata URI to that referenced by destURI.

Specified by:

renameMeta in class ReplicaInfo

Parameters:

destURI - the target URI.

Returns:

true if the rename is successful.

Throws:

IOException - if an exception occurs in the rename.

renameData

public boolean renameData(URI destURI)
                   throws IOException

Description copied from class: ReplicaInfo

Rename the data URI to that referenced by destURI.

Specified by:

renameData in class ReplicaInfo

Parameters:

destURI - the target URI.

Returns:

true if the rename is successful.

Throws:

IOException - if an exception occurs in the rename.

getPinning

public boolean getPinning(org.apache.hadoop.fs.LocalFileSystem localFS)
                   throws IOException

Description copied from class: ReplicaInfo

Check whether the block was pinned.

Specified by:

getPinning in class ReplicaInfo

Parameters:

localFS - the local filesystem to use.

Returns:

true if the block is pinned.

Throws:

IOException

setPinning

public void setPinning(org.apache.hadoop.fs.LocalFileSystem localFS)
                throws IOException

Description copied from class: ReplicaInfo

Set a block to be pinned on this datanode so that it cannot be moved by Balancer/Mover.

Specified by:

setPinning in class ReplicaInfo

Parameters:

localFS - the local filesystem to use.

Throws:

IOException - if there is an exception in the pinning.

bumpReplicaGS

public void bumpReplicaGS(long newGS)
                   throws IOException

Description copied from class: ReplicaInfo

Bump a replica's generation stamp to a new one. Its on-disk meta file name is renamed to be the new one too.

Specified by:

bumpReplicaGS in class ReplicaInfo

Parameters:

newGS - new generation stamp

Throws:

IOException - if the change fails

breakHardLinksIfNeeded

public boolean breakHardLinksIfNeeded()
                               throws IOException

Specified by:

breakHardLinksIfNeeded in class ReplicaInfo

Throws:

IOException

createInfo

public ReplicaRecoveryInfo createInfo()
                               throws UnsupportedOperationException

Specified by:

createInfo in class ReplicaInfo

Throws:

UnsupportedOperationException

compareWith

public int compareWith(FsVolumeSpi.ScanInfo info)

Specified by:

compareWith in class ReplicaInfo

truncateBlock

public void truncateBlock(long newLength)
                   throws IOException

Specified by:

truncateBlock in class ReplicaInfo

Throws:

IOException

updateWithReplica

public void updateWithReplica(StorageLocation replicaLocation)

Description copied from class: ReplicaInfo

Update this replica with the StorageLocation found.

Specified by:

updateWithReplica in class ReplicaInfo

Parameters:

replicaLocation - the StorageLocation found for this replica.

copyMetadata

public void copyMetadata(URI destination)
                  throws IOException

Specified by:

copyMetadata in class ReplicaInfo

Throws:

IOException

copyBlockdata

public void copyBlockdata(URI destination)
                   throws IOException

Specified by:

copyBlockdata in class ReplicaInfo

Throws:

IOException

setPathHandle

@VisibleForTesting
public void setPathHandle(org.apache.hadoop.fs.PathHandle pathHandle)