org.iq80.leveldb.util

Class LRUCache<K,V>

java.lang.Object

org.iq80.leveldb.util.LRUCache<K,V>

All Implemented Interfaces:

ILRUCache<K,V>

public final class LRUCache<K,V>
extends Object
implements ILRUCache<K,V>

LRU cache with special weigher to count correctly Slice weight.

Author:

Honore Vasconcelos

Method Summary

Modifier and Type	Method and Description
static <K,V> ILRUCache<K,V>	createCache(int capacity, com.google.common.cache.Weigher<K,V> weigher)
long	getApproximateMemoryUsage()
V	getIfPresent(K key) Get a value from cache if present (already loaded)
void	invalidateAll() Discards all entries in the cache.
V	load(K key, Callable<V> loader) Get cached valued by key or load and cache loaded value.

Methods inherited from class java.lang.Object

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

Method Detail

createCache

public static <K,V> ILRUCache<K,V> createCache(int capacity,
                                               com.google.common.cache.Weigher<K,V> weigher)

load

public V load(K key,
              Callable<V> loader)
       throws ExecutionException

Description copied from interface: ILRUCache

Get cached valued by key or load and cache loaded value.

Specified by:

load in interface ILRUCache<K,V>

Parameters:

key - cache key

loader - key value loader

Returns:

loaded/saved value

Throws:

ExecutionException - if load has any exception.

getApproximateMemoryUsage

public long getApproximateMemoryUsage()

Specified by:

getApproximateMemoryUsage in interface ILRUCache<K,V>

getIfPresent

public V getIfPresent(K key)

Description copied from interface: ILRUCache

Get a value from cache if present (already loaded)

Specified by:

getIfPresent in interface ILRUCache<K,V>

Parameters:

key - cache key

Returns:

value if present, otherwise

invalidateAll

public void invalidateAll()

Description copied from interface: ILRUCache

Discards all entries in the cache.

Specified by:

invalidateAll in interface ILRUCache<K,V>