/*
* This file is part of the Heritrix web crawler (crawler.archive.org).
*
* Licensed to the Internet Archive (IA) by one or more individual
* contributors.
*
* The IA 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.archive.util;
import java.util.LinkedHashMap;
import java.util.Map;
/**
* A least-recently used cache. As new entries are added to the map, the
* least-recently accessed entries are removed.
*
* @author pjack
*
* @param <K> The key type of the LRU
* @param <V> The value type of the LRU
*/
public class LRU<K,V> extends LinkedHashMap<K,V> {
/**
* Generated by Eclipse.
*/
private static final long serialVersionUID = 1032420936705267913L;
/**
* The maximum number of entries to store in the cache.
*/
private int max;
/**
* Constructor.
*
* @param max the maximum number of entries to cache
*/
public LRU(int max) {
super(max, (float)0.75, true);
this.max = max;
}
@Override
protected boolean removeEldestEntry(Map.Entry<K,V> entry) {
return size() >= max;
}
}