EntryWeigher.java

/*
 * Copyright 2017 OmniFaces
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 */
package org.omnifaces.util.concurrentlinkedhashmap;

/**
 * A class that can determine the weight of an entry. The total weight threshold
 * is used to determine when an eviction is required.
 *
 * @author ben.manes@gmail.com (Ben Manes)
 * @see <a href="https://github.com/ben-manes/concurrentlinkedhashmap">
 *      https://github.com/ben-manes/concurrentlinkedhashmap</a>
 */
@ThreadSafe
public interface EntryWeigher<K, V> {

  /**
   * Measures an entry's weight to determine how many units of capacity that
   * the key and value consumes. An entry must consume a minimum of one unit.
   *
   * @param key the key to weigh
   * @param value the value to weigh
   * @return the entry's weight
   */
  int weightOf(K key, V value);
}