org.apache.hadoop.hdfs.server.blockmanagement

Class BlockInfo

java.lang.Object

org.apache.hadoop.hdfs.protocol.Block

org.apache.hadoop.hdfs.server.blockmanagement.BlockInfo

All Implemented Interfaces:

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

Direct Known Subclasses:

BlockInfoUnderConstruction

public class BlockInfo
extends org.apache.hadoop.hdfs.protocol.Block
implements LightWeightGSet.LinkedElement

Internal class for block metadata.

Field Summary

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

BLOCK_FILE_PREFIX, blockFilePattern, METADATA_EXTENSION, metaFilePattern

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BlockInfo(BlockInfo from) Copy construction.
	BlockInfo(org.apache.hadoop.hdfs.protocol.Block blk, int replication)
	BlockInfo(int replication) Construct an entry for blocksmap

Method Summary

Methods

Modifier and Type	Method and Description
boolean	addNode(org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor node) Add data-node this block belongs to.
BlockInfoUnderConstruction	convertToBlockUnderConstruction(HdfsServerConstants.BlockUCState s, org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor[] targets) Convert a complete block to an under construction block.
boolean	equals(Object obj)
HdfsServerConstants.BlockUCState	getBlockUCState() BlockInfo represents a block that is not being constructed.
INodeFile	getINode()
LightWeightGSet.LinkedElement	getNext() Get the next element.
int	hashCode()
boolean	isComplete() Is this block complete?
BlockInfo	listInsert(BlockInfo head, org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor dn) Insert this block into the head of the list of blocks related to the specified DatanodeDescriptor.
BlockInfo	listRemove(BlockInfo head, org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor dn) Remove this block from the list of blocks related to the specified DatanodeDescriptor.
BlockInfo	moveBlockToHead(BlockInfo head, org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor dn, int curIndex, int headIndex) Remove this block from the list of blocks related to the specified DatanodeDescriptor.
boolean	removeNode(org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor node) Remove data-node from the block.
void	setINode(INodeFile inode)
void	setNext(LightWeightGSet.LinkedElement next) Set the next element.

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

compareTo, filename2id, getBlockId, getBlockId, getBlockName, getGenerationStamp, getGenerationStamp, getNumBytes, isBlockFilename, isMetaFilename, readFields, readId, set, setBlockId, setGenerationStamp, setNumBytes, toString, write, writeId

Methods inherited from class java.lang.Object

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

Constructor Detail

BlockInfo

public BlockInfo(int replication)

Construct an entry for blocksmap

Parameters:

replication - the block's replication factor

BlockInfo

public BlockInfo(org.apache.hadoop.hdfs.protocol.Block blk,
         int replication)

BlockInfo

protected BlockInfo(BlockInfo from)

Copy construction. This is used to convert BlockInfoUnderConstruction

Parameters:

from - BlockInfo to copy from.

Method Detail

getINode

public INodeFile getINode()

setINode

public void setINode(INodeFile inode)

addNode

public boolean addNode(org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor node)

Add data-node this block belongs to.

removeNode

public boolean removeNode(org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor node)

Remove data-node from the block.

listInsert

public BlockInfo listInsert(BlockInfo head,
                   org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor dn)

Insert this block into the head of the list of blocks related to the specified DatanodeDescriptor. If the head is null then form a new list.

Returns:

current block as the new head of the list.

listRemove

public BlockInfo listRemove(BlockInfo head,
                   org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor dn)

Remove this block from the list of blocks related to the specified DatanodeDescriptor. If this block is the head of the list then return the next block as the new head.

Returns:

the new head of the list or null if the list becomes empty after deletion.

moveBlockToHead

public BlockInfo moveBlockToHead(BlockInfo head,
                        org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor dn,
                        int curIndex,
                        int headIndex)

Remove this block from the list of blocks related to the specified DatanodeDescriptor. Insert it into the head of the list of blocks.

Returns:

the new head of the list.

getBlockUCState

public HdfsServerConstants.BlockUCState getBlockUCState()

BlockInfo represents a block that is not being constructed. In order to start modifying the block, the BlockInfo should be converted to BlockInfoUnderConstruction.

Returns:

HdfsServerConstants.BlockUCState.COMPLETE

isComplete

public boolean isComplete()

Is this block complete?

Returns:

true if the state of the block is HdfsServerConstants.BlockUCState.COMPLETE

convertToBlockUnderConstruction

public BlockInfoUnderConstruction convertToBlockUnderConstruction(HdfsServerConstants.BlockUCState s,
                                                         org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor[] targets)

Convert a complete block to an under construction block.

Returns:

BlockInfoUnderConstruction - an under construction block.

hashCode

public int hashCode()

Overrides:

hashCode in class org.apache.hadoop.hdfs.protocol.Block

equals

public boolean equals(Object obj)

Overrides:

equals in class org.apache.hadoop.hdfs.protocol.Block

getNext

public LightWeightGSet.LinkedElement getNext()

Description copied from interface: LightWeightGSet.LinkedElement

Get the next element.

Specified by:

getNext in interface LightWeightGSet.LinkedElement

setNext

public void setNext(LightWeightGSet.LinkedElement next)

Description copied from interface: LightWeightGSet.LinkedElement

Set the next element.

Specified by:

setNext in interface LightWeightGSet.LinkedElement