?/*
 * Copyright 2006-2007 original author or authors.
 *
 * Licensed 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.ecside.common;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;


/**
 * @author Wei Zijun
 *
 */

public class IndexHashMap extends HashMap  {

	private static final long serialVersionUID = -5156437706039907818L;

	private List list=new ArrayList();
	

	public Object put(Object key, Object value) {
		if (!containsKey(key)){
			list.add(key);
		}
		return super.put(key, value);
	}

	
	public Object get(int idx){
		return super.get(getKey(idx));
	}
	public int getIndex(Object key){
		return list.indexOf(key);
	}
	public Object getKey(int idx){
		if (idx>=list.size()) return null;
		return list.get(idx);
	}
	
	public void remove(int idx){
		Object key=getKey(idx);
		removeFromList(getIndex(key));
		super.remove(key);
	}
	
	public Object remove(Object key) {
		removeFromList(getIndex(key));
		return super.remove(key);
	}
	
	public void clear() {
		this.list = new ArrayList();
		super.clear();
	}
	private void removeFromList(int idx){
		if (idx<list.size() && idx>=0) {
			list.remove(idx);
		}
	}



}