Package org.qiunet.utils.collection.lru

Class LruHashMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

java.util.HashMap<K,V>

java.util.LinkedHashMap<K,V>

org.qiunet.utils.collection.lru.LruHashMap<K,V>

All Implemented Interfaces:

Serializable, Cloneable, Map<K,V>

public class LruHashMap<K,V>
extends LinkedHashMap<K,V>

LruHashMap is an extension of Java's HashMap, which has a bounded size(); When it reaches that size, each time a new element is added, the least recently used (LRU) entry is removed. Java makes it very easy to implement LruHashMap - all its functionality is already available from LinkedHashMap, and we just need to configure that properly. Note that LruHashMap is thread safe

Author:

kinson

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K extends Object,V extends Object>, AbstractMap.SimpleImmutableEntry<K extends Object,V extends Object>

Constructor Summary

Constructors

Constructor	Description
LruHashMap()
LruHashMap(int maxCapacity)

Method Summary

Modifier and Type	Method	Description
void	clear()
boolean	containsKey(Object key)
V	get(Object key)
int	getMaxCapacity()
V	put(K key, V value)
V	remove(Object key)
protected boolean	removeEldestEntry(Map.Entry<K,V> eldest)
void	setMaxCapacity(int maxCapacity)
int	size()

Methods inherited from class java.util.LinkedHashMap

containsValue, entrySet, forEach, getOrDefault, keySet, replaceAll, values

Methods inherited from class java.util.HashMap

clone, compute, computeIfAbsent, computeIfPresent, isEmpty, merge, putAll, putIfAbsent, remove, replace, replace

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

compute, computeIfAbsent, computeIfPresent, equals, hashCode, isEmpty, merge, putAll, putIfAbsent, remove, replace, replace

Constructor Details

LruHashMap

public LruHashMap()

LruHashMap

public LruHashMap(int maxCapacity)

Method Details

removeEldestEntry

protected boolean removeEldestEntry(Map.Entry<K,V> eldest)

Overrides:

removeEldestEntry in class LinkedHashMap<K,V>

containsKey

public boolean containsKey(Object key)

Specified by:

containsKey in interface Map<K,V>

Overrides:

containsKey in class HashMap<K,V>

get

public V get(Object key)

Specified by:

get in interface Map<K,V>

Overrides:

get in class LinkedHashMap<K,V>

put

public V put(K key,
 V value)

Specified by:

put in interface Map<K,V>

Overrides:

put in class HashMap<K,V>

remove

public V remove(Object key)

Specified by:

remove in interface Map<K,V>

Overrides:

remove in class HashMap<K,V>

size

public int size()

Specified by:

size in interface Map<K,V>

Overrides:

size in class HashMap<K,V>

clear

public void clear()

Specified by:

clear in interface Map<K,V>

Overrides:

clear in class LinkedHashMap<K,V>

getMaxCapacity

public int getMaxCapacity()

setMaxCapacity

public void setMaxCapacity(int maxCapacity)