content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements. See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.apache.kafka.common.cache;
  
  import java.util.LinkedHashMap;
  import java.util.Map;
  
  /**
   * A cache implementing a least recently used policy.
   */
  public class LRUCache<K, V> implements Cache<K, V> {
      private final LinkedHashMap<K, V> cache;
  
      public LRUCache(final int maxSize) {
          cache = new LinkedHashMap<>(16, .75f, true) {
              @Override
              protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
                  return this.size() > maxSize; // require this. prefix to make lgtm.com happy
              }
          };
      }
  
      @Override
      public V get(K key) {
          return cache.get(key);
      }
  
      @Override
      public void put(K key, V value) {
          cache.put(key, value);
      }
  
      @Override
      public boolean remove(K key) {
          return cache.remove(key) != null;
      }
  
      @Override
      public long size() {
          return cache.size();
      }
  }
  