Copyright (c) 2000, 2016 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2016 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.jdt.internal.corext.util;

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

Least-recently-used cache. When the map tops the maximum size configured in the constructor, it
automatically removes the oldest entry in terms of last access.

Invoking the put or get method results in an access to the corresponding entry.
The putAll method generates one entry access for each mapping in the specified map, in
the order that key-value mappings are provided by the specified map's entry set iterator. No
other methods generate entry accesses. In particular, operations on collection-views do
not affect the order of iteration of the backing map.
Type parameters:
<K> – type of the keys
<V> – type of the values/**
 * Least-recently-used cache. When the map tops the maximum size configured in the constructor, it
 * automatically removes the oldest entry in terms of last access.
 * <p>
 * Invoking the <tt>put</tt> or <tt>get</tt> method results in an access to the corresponding entry.
 * The <tt>putAll</tt> method generates one entry access for each mapping in the specified map, in
 * the order that key-value mappings are provided by the specified map's entry set iterator. <i>No
 * other methods generate entry accesses.</i> In particular, operations on collection-views do
 * <i>not</i> affect the order of iteration of the backing map.
 * 
 * @param <K> type of the keys
 * @param <V> type of the values
 */
public class LRUMap<K,V> extends LinkedHashMap<K,V> {

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

	
Creates an empty LRU map with the given maximum size.
Params:
maxSize – the maximum number of elements in the cache/**
	 * Creates an empty LRU map with the given maximum size.
	 * 
	 * @param maxSize the maximum number of elements in the cache
	 */
	public LRUMap(int maxSize) {
		super(maxSize, 0.75f, true);
		fMaxSize= maxSize;
	}

	@Override
	protected boolean removeEldestEntry(Map.Entry<K,V> eldest) {
		return size() > fMaxSize;
	}
}