Package net.i2p.router.networkdb.kademlia

Class LocalHash

java.lang.Object

net.i2p.data.SimpleDataStructure

net.i2p.data.Hash

net.i2p.router.networkdb.kademlia.LocalHash

All Implemented Interfaces:

DataStructure

class LocalHash
extends Hash

Pull the caching used only by KBucketImpl out of Hash and put it here.

Since:

0.7.14

Author:

jrandom, moved from Hash.java by zzz

Field Summary

Fields inherited from class net.i2p.data.Hash

FAKE_HASH, HASH_LENGTH

Fields inherited from class net.i2p.data.SimpleDataStructure

_data

Constructor Summary

Constructors

Constructor	Description
LocalHash(byte[] b)
LocalHash(Hash h)

Method Summary

Modifier and Type	Method	Description
byte[]	cachedXor(Hash key)	Calculate the xor with the current object and the specified hash, caching values where possible.
void	clearXorCache()
void	prepareCache()	Prepare this hash's cache for xor values - very few hashes will need it, so we don't want to waste the memory, and lazy initialization would incur online overhead to verify the initialization.

Methods inherited from class net.i2p.data.Hash

clearCache, create, create, create, hashCode, length, readBytes, setData, toBase32, toBase64

Methods inherited from class net.i2p.data.SimpleDataStructure

calculateHash, equals, fromBase64, fromByteArray, getData, read, toByteArray, toString, writeBytes

Methods inherited from class java.lang.Object

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

Constructor Details

LocalHash

public LocalHash(Hash h)

LocalHash

public LocalHash(byte[] b)

Method Details

prepareCache

public void prepareCache()

Prepare this hash's cache for xor values - very few hashes will need it, so we don't want to waste the memory, and lazy initialization would incur online overhead to verify the initialization.

cachedXor

public byte[] cachedXor(Hash key)
                 throws IllegalStateException

Calculate the xor with the current object and the specified hash, caching values where possible. Currently this keeps up to MAX_CACHED_XOR (1024) entries, and uses an essentially random ejection policy. Later perhaps go for an LRU or FIFO?

Throws:

IllegalStateException - if you try to use the cache without first preparing this object's cache via .prepareCache()

clearXorCache

public void clearXorCache()