com.cloudant.client.cache

Class LRUCache<K,V>

java.lang.Object

com.cloudant.client.cache.LRUCache<K,V>

Type Parameters:

K - the type of the cache keys

V - the type of the cache values

All Implemented Interfaces:

Cache<K,V>

public class LRUCache<K,V>
extends java.lang.Object
implements Cache<K,V>

A Least Recently Used (LRU) cache. New objects are added to the cache up to the capacity after which any further additions will result in the removal of the key-value pair that was accessed least recently.

Constructor Summary

Constructors

Constructor and Description
LRUCache(int cacheCapacity) Create a new LRUCache with the specified capacity.

Method Summary

Modifier and Type	Method and Description
void	clear() Delete all entries from the cache.
void	delete(K key) Delete a key-value pair from the cache.
void	deleteAll(java.util.List<K> keys) Delete one or more key-value pairs from the cache.
V	get(K key) Look up a value in the cache.
java.util.Map<K,V>	getAll(java.util.List<K> keys) Look up one or more values in the cache.
Stats<java.lang.Void>	getStatistics() This cache implementation does not provide any statistics.
void	put(K key, V value) Cache a key-value pair.
void	putAll(java.util.Map<K,V> map) Cache one or more key-value pairs.
long	size()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

LRUCache

public LRUCache(int cacheCapacity)

Create a new LRUCache with the specified capacity.

Parameters:

cacheCapacity - maximum number of entries to store

Method Detail

clear

public void clear()

Delete all entries from the cache.

Specified by:

clear in interface Cache<K,V>

delete

public void delete(K key)

Delete a key-value pair from the cache.

Specified by:

delete in interface Cache<K,V>

Parameters:

key - key corresponding to value

deleteAll

public void deleteAll(java.util.List<K> keys)

Delete one or more key-value pairs from the cache.

Specified by:

deleteAll in interface Cache<K,V>

Parameters:

keys - List containing the keys to delete

get

public V get(K key)

Look up a value in the cache.

Specified by:

get in interface Cache<K,V>

Parameters:

key - key corresponding to value

Returns:

value corresponding to key, null if key is not in cache or if value is expired

getAll

public java.util.Map<K,V> getAll(java.util.List<K> keys)

Look up one or more values in the cache. Don't return expired values.

Specified by:

getAll in interface Cache<K,V>

Parameters:

keys - List containing the keys to look up

Returns:

map containing key-value pairs corresponding to unexpired data in the cache

getStatistics

public Stats<java.lang.Void> getStatistics()

This cache implementation does not provide any statistics. Calling Stats.getStats() will return null.

Specified by:

getStatistics in interface Cache<K,V>

Returns:

a Stats implementation that always returns null for calls to getStats()

put

public void put(K key,
                V value)

Cache a key-value pair.

Specified by:

put in interface Cache<K,V>

Parameters:

key - key associated with value

value - value associated with key

putAll

public void putAll(java.util.Map<K,V> map)

Cache one or more key-value pairs.

Specified by:

putAll in interface Cache<K,V>

Parameters:

map - map containing key-value pairs to cache

size

public long size()

Specified by:

size in interface Cache<K,V>

Returns:

the number of objects in cache