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base on h2database 1.4.196. for more information, see http://h2database.com/

There is a newer version: 1.2

/*
 * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
 * and the EPL 1.0 (http://h2database.com/html/license.html).
 * Initial Developer: H2 Group
 */
package org.h2.util;

import java.util.LinkedHashMap;
import java.util.Map;

/**
 * This class implements a small LRU object cache.
 *
 * @param  the key
 * @param  the value
 */
public class SmallLRUCache extends LinkedHashMap {

    private static final long serialVersionUID = 1L;
    private int size;

    private SmallLRUCache(int size) {
        super(size, (float) 0.75, true);
        this.size = size;
    }

    /**
     * Create a new object with all elements of the given collection.
     *
     * @param  the key type
     * @param  the value type
     * @param size the number of elements
     * @return the object
     */
    public static  SmallLRUCache newInstance(int size) {
        return new SmallLRUCache<>(size);
    }

    public void setMaxSize(int size) {
        this.size = size;
    }

    @Override
    protected boolean removeEldestEntry(Map.Entry eldest) {
        return size() > size;
    }

}