org.apache.camel.util

Class LRUCache<K,V>

java.lang.Object

org.apache.camel.util.LRUCache<K,V>

All Implemented Interfaces:

com.github.benmanes.caffeine.cache.RemovalListener<K,V>, Serializable, Map<K,V>

Direct Known Subclasses:

LRUSoftCache, LRUWeakCache

public class LRUCache<K,V>
extends Object
implements Map<K,V>, com.github.benmanes.caffeine.cache.RemovalListener<K,V>, Serializable

A cache that uses a near optional LRU Cache.

The Cache is implemented by Caffeine which provides an efficient cache.

If this cache stores Service then this implementation will on eviction invoke the Service.stop() method, to auto-stop the service.

Use LRUCacheFactory to create a new instance (do not use the constructor).

See Also:

LRUCacheFactory, LRUSoftCache, LRUWeakCache, Serialized Form

Nested Class Summary

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

Map.Entry<K,V>

Field Summary

Fields

Modifier and Type	Field and Description
protected LongAdder	evicted
protected LongAdder	hits
protected LongAdder	misses

Constructor Summary

Constructors

Constructor and Description
LRUCache(int maximumCacheSize) Constructs an empty LRUCache instance with the specified maximumCacheSize, and will stop on eviction.
LRUCache(int initialCapacity, int maximumCacheSize) Constructs an empty LRUCache instance with the specified initial capacity, maximumCacheSize, and will stop on eviction.
LRUCache(int initialCapacity, int maximumCacheSize, boolean stopOnEviction) Constructs an empty LRUCache instance with the specified initial capacity, maximumCacheSize,load factor and ordering mode.
LRUCache(int initialCapacity, int maximumCacheSize, boolean stopOnEviction, boolean soft, boolean weak, boolean syncListener) Constructs an empty LRUCache instance with the specified initial capacity, maximumCacheSize,load factor and ordering mode.

Method Summary

Modifier and Type	Method and Description
void	cleanUp()
void	clear()
boolean	containsKey(Object o)
boolean	containsValue(Object o)
Set<Map.Entry<K,V>>	entrySet()
V	get(Object o)
long	getEvicted() Gets the number of evicted entries.
long	getHits() Gets the number of cache hits
int	getMaxCacheSize() Returns the maxCacheSize.
long	getMisses() Gets the number of cache misses.
boolean	isEmpty()
Set<K>	keySet()
void	onRemoval(K key, V value, com.github.benmanes.caffeine.cache.RemovalCause cause)
V	put(K k, V v)
void	putAll(Map<? extends K,? extends V> map)
V	remove(Object o)
void	resetStatistics() Rest the cache statistics such as hits and misses.
int	size()
String	toString()
Collection<V>	values()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

Field Detail

hits

protected final LongAdder hits

misses

protected final LongAdder misses

evicted

protected final LongAdder evicted

Constructor Detail

LRUCache

public LRUCache(int maximumCacheSize)

Constructs an empty LRUCache instance with the specified maximumCacheSize, and will stop on eviction.

Parameters:

maximumCacheSize - the max capacity.

Throws:

IllegalArgumentException - if the initial capacity is negative

LRUCache

public LRUCache(int initialCapacity,
                int maximumCacheSize)

Constructs an empty LRUCache instance with the specified initial capacity, maximumCacheSize, and will stop on eviction.

Parameters:

initialCapacity - the initial capacity.

maximumCacheSize - the max capacity.

Throws:

IllegalArgumentException - if the initial capacity is negative

LRUCache

public LRUCache(int initialCapacity,
                int maximumCacheSize,
                boolean stopOnEviction)

Constructs an empty LRUCache instance with the specified initial capacity, maximumCacheSize,load factor and ordering mode.

Parameters:

initialCapacity - the initial capacity.

maximumCacheSize - the max capacity.

stopOnEviction - whether to stop service on eviction.

Throws:

IllegalArgumentException - if the initial capacity is negative

LRUCache

public LRUCache(int initialCapacity,
                int maximumCacheSize,
                boolean stopOnEviction,
                boolean soft,
                boolean weak,
                boolean syncListener)

Constructs an empty LRUCache instance with the specified initial capacity, maximumCacheSize,load factor and ordering mode.

Parameters:

initialCapacity - the initial capacity.

maximumCacheSize - the max capacity.

stopOnEviction - whether to stop service on eviction.

soft - whether to use soft values a soft cache (default is false)

weak - whether to use weak keys/values as a weak cache (default is false)

syncListener - whether to use synchronous call for the eviction listener (default is false)

Throws:

IllegalArgumentException - if the initial capacity is negative

Method Detail

get

public V get(Object o)

Specified by:

get in interface Map<K,V>

size

public int size()

Specified by:

size in interface Map<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<K,V>

containsKey

public boolean containsKey(Object o)

Specified by:

containsKey in interface Map<K,V>

containsValue

public boolean containsValue(Object o)

Specified by:

containsValue in interface Map<K,V>

put

public V put(K k,
             V v)

Specified by:

put in interface Map<K,V>

remove

public V remove(Object o)

Specified by:

remove in interface Map<K,V>

putAll

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

Specified by:

putAll in interface Map<K,V>

clear

public void clear()

Specified by:

clear in interface Map<K,V>

keySet

public Set<K> keySet()

Specified by:

keySet in interface Map<K,V>

values

public Collection<V> values()

Specified by:

values in interface Map<K,V>

entrySet

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

Specified by:

entrySet in interface Map<K,V>

onRemoval

public void onRemoval(K key,
                      V value,
                      com.github.benmanes.caffeine.cache.RemovalCause cause)

Specified by:

onRemoval in interface com.github.benmanes.caffeine.cache.RemovalListener<K,V>

getHits

public long getHits()

Gets the number of cache hits

getMisses

public long getMisses()

Gets the number of cache misses.

getEvicted

public long getEvicted()

Gets the number of evicted entries.

getMaxCacheSize

public int getMaxCacheSize()

Returns the maxCacheSize.

resetStatistics

public void resetStatistics()

Rest the cache statistics such as hits and misses.

cleanUp

public void cleanUp()

toString

public String toString()

Overrides:

toString in class Object