org.rakeshv.utils
Class LRU<K,V>

java.lang.Object
  java.util.AbstractMap<K,V>
      java.util.HashMap<K,V>
          java.util.LinkedHashMap<K,V>
              org.rakeshv.utils.LinkedHashMap<K,V>
                  org.rakeshv.utils.LRU<K,V>

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.util.Map<K,V>

 class LRU<K,V>
extends LinkedHashMap<K,V>

A Least Recently Used implementation using a LinkedHashMap.

Note: This class uses the LinkedHashMap introducted in the Java 1.4 version, and replaces the old implementation that has been renamed as SimpleLRU.

Copyright 2004-2006 Rakesh Vidyadharan

Version:

$Id: LRU.java,v 1.9 2006/03/11 04:15:14 rakesh Exp $

Author:

Rakesh Vidyadharan 2004 May 2

Nested Class Summary

Nested classes/interfaces inherited from class org.rakeshv.utils.LinkedHashMap

LinkedHashMap.Statistics

Nested classes/interfaces inherited from interface java.util.Map

java.util.Map.Entry<K,V>

Field Summary

Fields inherited from class org.rakeshv.utils.LinkedHashMap

DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR, FIFO_CACHE, LRU_CACHE

Constructor Summary

LRU()
Default constructor.

LRU(int capacity)
Constructs an empty access-ordered instance with the specified initial capacity and a default load factor of LinkedHashMap.DEFAULT_LOAD_FACTOR.

LRU(int capacity, float loadFactor)
Constructs an empty access-ordered instance with the specified initial capacity and load factor.

LRU(java.util.Map<K,V> map)
Constructs an access-ordered LRU instance with the same mappings as the specified map.

Method Summary

Methods inherited from class org.rakeshv.utils.LinkedHashMap

clear, get, getMaxEntries, getStatistics, removeEldestEntry, setMaxEntries

Methods inherited from class java.util.LinkedHashMap

containsValue

Methods inherited from class java.util.HashMap

clone, containsKey, entrySet, isEmpty, keySet, put, putAll, remove, size, values

Methods inherited from class java.util.AbstractMap

equals, hashCode, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

containsKey, containsValue, entrySet, equals, hashCode, isEmpty, keySet, put, putAll, remove, size, values

Constructor Detail

LRU

LRU()

Default constructor. Creates a new Map with LinkedHashMap.DEFAULT_CAPACITY capacity and a load factor of LinkedHashMap.DEFAULT_LOAD_FACTOR. If this form of the constructor is used, then the cache size will not be controlled.

See Also:

LRU( int, float )

LRU

LRU(int capacity)

Constructs an empty access-ordered instance with the specified initial capacity and a default load factor of LinkedHashMap.DEFAULT_LOAD_FACTOR.

Parameters:

capacity - The maximum size for this map.

See Also:

LRU( int, float )

LRU

LRU(int capacity,
    float loadFactor)

Constructs an empty access-ordered instance with the specified initial capacity and load factor. This is the designated constructor that is used by all other constructors.

Parameters:

capacity - The maximum size for this map.

loadFactor - The load-factor to use.

LRU

LRU(java.util.Map<K,V> map)

Constructs an access-ordered LRU instance with the same mappings as the specified map. The LRU instance is created with a a default load factor of LinkedHashMap.DEFAULT_LOAD_FACTOR and a capacity sufficient to hold the mappings in the specified map.

Parameters:

map - The map to use to create the new instance.

Throws:

java.lang.NullPointerException - If the specified map is null.

See Also:

LRU( int )