org.apache.camel.util
Class LRUWeakCache<K,V>

java.lang.Object
  org.apache.camel.util.LRUCache<K,V>
      org.apache.camel.util.LRUWeakCache<K,V>

All Implemented Interfaces:

com.googlecode.concurrentlinkedhashmap.EvictionListener<K,V>, Serializable, Map<K,V>

public class LRUWeakCache<K,V>
extends LRUCache<K,V>

A Least Recently Used Cache which uses WeakReference.

This implementation uses WeakReference for stored values in the cache, to support the JVM when it wants to reclaim objects for example during garbage collection. Therefore this implementation does not support all the Map methods.

The following methods is only be be used:

• containsKey - To determine if the key is in the cache and refers to a value
• entrySet - To return a set of all the entries (as key/value paris)
• get - To get a value from the cache
• isEmpty - To determine if the cache contains any values
• keySet - To return a set of the current keys which refers to a value
• put - To add a value to the cache
• putAll - To add values to the cache
• remove - To remove a value from the cache by its key
• size - To get the current size
• values - To return a copy of all the value in a list

The LRUCache.containsValue(Object) method should not be used as it's not adjusted to check for the existence of a value without catering for the soft references.

Notice that if the JVM reclaim memory the content of this cache may be garbage collected, without any eviction notifications.

See Also:

LRUCache, LRUSoftCache, Serialized Form

Nested Class Summary

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

Map.Entry<K,V>

Constructor Summary

LRUWeakCache(int maximumCacheSize)

LRUWeakCache(int initialCapacity, int maximumCacheSize)

Method Summary

boolean	containsKey(Object o)
Set<Map.Entry<K,V>>	entrySet()
V	get(Object o)
boolean	isEmpty()
V	put(K key, V value)
void	putAll(Map<? extends K,? extends V> map)
V	remove(Object o)
int	size()
String	toString()
Collection<V>	values()

Methods inherited from class org.apache.camel.util.LRUCache

clear, containsValue, getEvicted, getHits, getMaxCacheSize, getMisses, keySet, onEviction, resetStatistics

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

equals, hashCode

Constructor Detail

LRUWeakCache

public LRUWeakCache(int maximumCacheSize)

LRUWeakCache

public LRUWeakCache(int initialCapacity,
                    int maximumCacheSize)

Method Detail

put

public V put(K key,
             V value)

Specified by:

put in interface Map<K,V>

Overrides:

put in class LRUCache<K,V>

get

public V get(Object o)

Specified by:

get in interface Map<K,V>

Overrides:

get in class LRUCache<K,V>

putAll

public void putAll(Map<? extends K,? extends V> map)

Specified by:

putAll in interface Map<K,V>

Overrides:

putAll in class LRUCache<K,V>

remove

public V remove(Object o)

Specified by:

remove in interface Map<K,V>

Overrides:

remove in class LRUCache<K,V>

values

public Collection<V> values()

Specified by:

values in interface Map<K,V>

Overrides:

values in class LRUCache<K,V>

size

public int size()

Specified by:

size in interface Map<K,V>

Overrides:

size in class LRUCache<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<K,V>

Overrides:

isEmpty in class LRUCache<K,V>

containsKey

public boolean containsKey(Object o)

Specified by:

containsKey in interface Map<K,V>

Overrides:

containsKey in class LRUCache<K,V>

entrySet

public Set<Map.Entry<K,V>> entrySet()

Specified by:

entrySet in interface Map<K,V>

Overrides:

entrySet in class LRUCache<K,V>

toString

public String toString()

Overrides:

toString in class LRUCache<K,V>