alluxio.worker.block.meta

Class AbstractBlockMeta

java.lang.Object

alluxio.worker.block.meta.AbstractBlockMeta

Direct Known Subclasses:

BlockMeta, TempBlockMeta

@ThreadSafe
public abstract class AbstractBlockMeta
extends Object

A base class of the metadata of blocks in Alluxio managed storage.

Field Summary

Fields

Modifier and Type	Field and Description
protected long	mBlockId
protected StorageDir	mDir

Constructor Summary

Constructors

Constructor and Description
AbstractBlockMeta(long blockId, StorageDir dir) Creates a new instance of AbstractBlockMeta.

Method Summary

Modifier and Type	Method and Description
static String	commitPath(StorageDir dir, long blockId) Committed block is stored in BlockStore under its StorageDir as a block file named after its blockId.
long	getBlockId()
BlockStoreLocation	getBlockLocation()
abstract long	getBlockSize()
StorageDir	getParentDir()
abstract String	getPath()
static String	tempPath(StorageDir dir, long sessionId, long blockId) All blocks are created as temp blocks before committed.

Methods inherited from class java.lang.Object

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

Field Detail

mBlockId

protected final long mBlockId

mDir

protected final StorageDir mDir

Constructor Detail

AbstractBlockMeta

public AbstractBlockMeta(long blockId,
                         StorageDir dir)

Creates a new instance of AbstractBlockMeta.

Parameters:

blockId - the block id

dir - the parent directory

Method Detail

tempPath

public static String tempPath(StorageDir dir,
                              long sessionId,
                              long blockId)

All blocks are created as temp blocks before committed. They are stored in BlockStore under a subdir of its StorageDir, the subdir is tmpFolder/sessionId % maxSubdirMax. tmpFolder is a property of PropertyKey.WORKER_DATA_TMP_FOLDER. maxSubdirMax is a property of PropertyKey.WORKER_DATA_TMP_SUBDIR_MAX. The block file name is "sessionId-blockId". e.g. sessionId 2 creates a temp Block 100 in StorageDir "/mnt/mem/0", this temp block has path:

/mnt/mem/0/.tmp_blocks/2/2-100

Parameters:

dir - the parent directory

sessionId - the session id

blockId - the block id

Returns:

temp file path

commitPath

public static String commitPath(StorageDir dir,
                                long blockId)

Committed block is stored in BlockStore under its StorageDir as a block file named after its blockId. e.g. Block 100 of StorageDir "/mnt/mem/0" has path:

/mnt/mem/0/100

Parameters:

blockId - the block id

dir - the parent directory

Returns:

committed file path

getBlockId

public long getBlockId()

Returns:

the block id

getBlockLocation

public BlockStoreLocation getBlockLocation()

Returns:

location of the block

getParentDir

public StorageDir getParentDir()

Returns:

the parent directory

getPath

public abstract String getPath()

Returns:

the block path

getBlockSize

public abstract long getBlockSize()

Returns:

the block size