/*
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
package com.facebook.imagepipeline.cache;
import javax.annotation.Nullable;
import com.facebook.common.internal.Predicate;
import com.facebook.common.references.CloseableReference;
/**
* Interface for the image pipeline memory cache.
*
* @param <K> the key type
* @param <V> the value type
*/
public interface MemoryCache<K, V> {
/**
* Caches the the given key-value pair.
*
* <p> The cache returns a new copy of the provided reference which should be used instead of the
* original one. The client should close the returned reference when it is not required anymore.
*
* <p> If the cache failed to cache the given value, then the null reference is returned.
*
* @param key
* @param value
* @return a new reference to be used, or null if the caching failed
*/
@Nullable
CloseableReference<V> cache(K key, CloseableReference<V> value);
/**
* Gets the item with the given key, or null if there is no such item.
*
* @param key
* @return a reference to the cached value, or null if the item was not found
*/
@Nullable
CloseableReference<V> get(K key);
/**
* Removes all the items from the cache whose keys match the specified predicate.
*
* @param predicate returns true if an item with the given key should be removed
* @return number of the items removed from the cache
*/
public int removeAll(Predicate<K> predicate);
/**
* Find if any of the items from the cache whose keys match the specified predicate.
*
* @param predicate returns true if an item with the given key matches
* @return true if the predicate was found in the cache, false otherwise
*/
public boolean contains(Predicate<K> predicate);
}