org.apache.hadoop.hbase.io.hfile

Class CachedBlock

java.lang.Object

org.apache.hadoop.hbase.io.hfile.CachedBlock

All Implemented Interfaces:

Comparable<CachedBlock>, HeapSize

@InterfaceAudience.Private
public class CachedBlock
extends Object
implements HeapSize, Comparable<CachedBlock>

Represents an entry in the LruBlockCache.

Makes the block memory-aware with HeapSize and Comparable to sort by access time for the LRU. It also takes care of priority by either instantiating as in-memory or handling the transition from single to multiple access.

Field Summary

Fields

Modifier and Type	Field and Description
static long	PER_BLOCK_OVERHEAD

Constructor Summary

Constructors

Constructor and Description
CachedBlock(BlockCacheKey cacheKey, Cacheable buf, long accessTime)
CachedBlock(BlockCacheKey cacheKey, Cacheable buf, long accessTime, boolean inMemory)

Method Summary

Methods

Modifier and Type	Method and Description
void	access(long accessTime) Block has been accessed.
int	compareTo(CachedBlock that)
boolean	equals(Object obj)
Cacheable	getBuffer()
BlockCacheKey	getCacheKey()
org.apache.hadoop.hbase.io.hfile.CachedBlock.BlockPriority	getPriority()
long	heapSize()

Methods inherited from class java.lang.Object

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

Field Detail

PER_BLOCK_OVERHEAD

public static final long PER_BLOCK_OVERHEAD

Constructor Detail

CachedBlock

public CachedBlock(BlockCacheKey cacheKey,
           Cacheable buf,
           long accessTime)

CachedBlock

public CachedBlock(BlockCacheKey cacheKey,
           Cacheable buf,
           long accessTime,
           boolean inMemory)

Method Detail

access

public void access(long accessTime)

Block has been accessed. Update its local access time.

heapSize

public long heapSize()

Specified by:

heapSize in interface HeapSize

compareTo

public int compareTo(CachedBlock that)

Specified by:

compareTo in interface Comparable<CachedBlock>

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

getBuffer

public Cacheable getBuffer()

getCacheKey

public BlockCacheKey getCacheKey()

getPriority

public org.apache.hadoop.hbase.io.hfile.CachedBlock.BlockPriority getPriority()