org.trimou.engine.cache

Interface ComputingCache<K,V>

Type Parameters:

K - The key

V - The value

public interface ComputingCache<K,V>

A simple abstraction for computing (lazy loading) cache. It may not contain null values. An implementation must be thread-safe.

Since:

1.7

Author:

Martin Kouba

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	ComputingCache.Function<K,V>
static interface	ComputingCache.KeyPredicate<K>
static interface	ComputingCache.Listener<K>

Method Summary

Modifier and Type	Method and Description
void	clear() Clear the cache.
V	get(K key)
Map<K,V>	getAllPresent()
V	getIfPresent(K key)
void	invalidate(ComputingCache.KeyPredicate<K> keyPredicate) Invalidate all entries whose keys satisfy a predicate.
long	size() The expired entries may be also counted, but will never be visible to other read/write operations.

Method Detail

get

V get(K key)

Parameters:

key -

Returns:

a value for a key, computing the value if necessary

getIfPresent

V getIfPresent(K key)

Parameters:

key -

Returns:

a value for a key or null if no such value exists

clear

void clear()

Clear the cache.

size

long size()

The expired entries may be also counted, but will never be visible to other read/write operations.

Returns:

the number of cached entries

invalidate

void invalidate(ComputingCache.KeyPredicate<K> keyPredicate)

Invalidate all entries whose keys satisfy a predicate.

Parameters:

keyPredicate -

getAllPresent

Map<K,V> getAllPresent()

Returns:

an immutable map of the values which are present in the cache at the time this method is called