1/*
2 * Copyright (C) 2011 The Guava Authors
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.google.common.cache;
18
19import com.google.common.annotations.Beta;
20
21/**
22 * Calculates the weights of cache entries.
23 *
24 * @author fry@google.com (Charles Fry)
25 * @since 11.0
26 */
27@Beta
28public interface Weigher<K, V> {
29
30  /**
31   * Returns the weight of a cache entry. There is no unit for entry weights; rather they are simply
32   * relative to each other.
33   *
34   * @return the weight of the entry; must be non-negative
35   */
36  int weigh(K key, V value);
37
38}
39