MapEntry.java

/*
 * Distributed as part of mchange-commons-java 0.2.11
 *
 * Copyright (C) 2015 Machinery For Change, Inc.
 *
 * Author: Steve Waldman <swaldman@mchange.com>
 *
 * This library is free software; you can redistribute it and/or modify
 * it under the terms of EITHER:
 *
 *     1) The GNU Lesser General Public License (LGPL), version 2.1, as 
 *        published by the Free Software Foundation
 *
 * OR
 *
 *     2) The Eclipse Public License (EPL), version 1.0
 *
 * You may choose which license to accept if you wish to redistribute
 * or modify this work. You may offer derivatives of this work
 * under the license you have chosen, or you may provide the same
 * choice of license which you have been offered here.
 *
 * This software 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.
 *
 * You should have received copies of both LGPL v2.1 and EPL v1.0
 * along with this software; see the files LICENSE-EPL and LICENSE-LGPL.
 * If not, the text of these licenses are currently available at
 *
 * LGPL v2.1: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 *  EPL v1.0: http://www.eclipse.org/org/documents/epl-v10.php 
 * 
 */

package com.mchange.v2.collection;

import java.util.*;
import com.mchange.v2.lang.ObjectUtils;

public class MapEntry implements Map.Entry
{
    Object key;
    Object value;

    public MapEntry( Object key, Object value )
    { 
	this.key = key;
	this.value = value;
    }

    public Object getKey()
    { return key; }

    public Object getValue()
    { return value;  }

    public Object setValue(Object o)
    { throw new UnsupportedOperationException(); }

    public boolean equals(Object o)
    {
	if (o instanceof Map.Entry)
	    {
		Map.Entry other = (Map.Entry) o;
		return 
		    ObjectUtils.eqOrBothNull( this.key   , other.getKey() ) &&
		    ObjectUtils.eqOrBothNull( this.value , other.getValue() );
		
	    }
	else
	    return false;
    }

    /*
     * Conforms to required contract for Map.Entry hashCode()
     */
    public int hashCode()
    {
	return 
	    ObjectUtils.hashOrZero( this.key ) ^
	    ObjectUtils.hashOrZero( this.value );
    }
}