org.antlr.v4.misc.OrderedHashMap Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of antlr4 Show documentation

The ANTLR 4 grammar compiler.

There is a newer version: 4.9.0

/*
 * Copyright (c) 2012 The ANTLR Project. All rights reserved.
 * Use of this file is governed by the BSD-3-Clause license that
 * can be found in the LICENSE.txt file in the project root.
 */

package org.antlr.v4.misc;

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/** I need the get-element-i functionality so I'm subclassing
 *  LinkedHashMap.
 */
public class OrderedHashMap extends LinkedHashMap {
	private static final long serialVersionUID = -4127551298268351889L;

	/** Track the elements as they are added to the set */
	protected List elements = new ArrayList();

	public K getKey(int i) { return elements.get(i); }

	public V getElement(int i) { return get(elements.get(i)); }

	@Override
	public V put(K key, V value) {
		elements.add(key);
		return super.put(key, value);
	}

	@Override
	public void putAll(Map m) {
		for (Map.Entry entry : m.entrySet()) {
			put(entry.getKey(), entry.getValue());
		}
	}

	@Override
	public V remove(Object key) {
		elements.remove(key);
		return super.remove(key);
	}

	@Override
	public void clear() {
		elements.clear();
		super.clear();
	}
}