/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* Copyright (c) 2010, Red Hat Inc. or third-party contributors as
* indicated by the @author tags or express copyright attribution
* statements applied by the authors. All third-party contributions are
* distributed under license by Red Hat Inc.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program 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 Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package org.hibernate.internal.util.collections;
import java.io.Serializable;
import java.util.LinkedHashMap;
import java.util.Map;
/**
* A simple LRU cache that implements the <code>Map</code> interface. Instances
* are not thread-safe and should be synchronized externally, for instance by
* using {@link java.util.Collections#synchronizedMap}.
*
* @author Manuel Dominguez Sarmiento
*/
public class LRUMap extends LinkedHashMap implements Serializable {
private static final long serialVersionUID = -5522608033020688048L;
private final int maxEntries;
public LRUMap(int maxEntries) {
super( maxEntries, .75f, true );
this.maxEntries = maxEntries;
}
@Override
protected boolean removeEldestEntry(Map.Entry eldest) {
return ( size() > maxEntries );
}
}