/*******************************************************************************
* Copyright (c) 2006-2011 Gluster, Inc. <http://www.gluster.com>
* This file is part of Gluster Management Console.
*
* Gluster Management Console is free software; you can redistribute
* it and/or modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* Gluster Management Console is distributed in the hope that it
* will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see
* <http://www.gnu.org/licenses/>.
*******************************************************************************/
package org.gluster.storage.management.core.utils;
import java.util.LinkedHashMap;
import java.util.Map;
/**
* An LRU cache, based on <code>LinkedHashMap</code>.
* <p>
* This cache has a fixed maximum number of elements (<code>cacheSize</code>). If the cache is full and another entry is
* added, the LRU (least recently used) entry is dropped.
*
*/
public class LRUCache<K, V> extends LinkedHashMap<K, V> {
private static final long serialVersionUID = 1L;
private static final float loadFactor = 0.75f;
private int cacheSize;
/**
* Creates a new LRU cache.
*
* @param cacheSize
* the maximum number of entries that will be kept in this cache.
*/
public LRUCache(int cacheSize) {
super((int) Math.ceil(cacheSize / loadFactor) + 1, loadFactor, true);
this.cacheSize = cacheSize;
}
@Override
protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
return size() > cacheSize;
}
}