com.mchange.v1.util.MapUtils Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of org.apache.servicemix.bundles.mchange-commons-java

This OSGi bundle wraps ${pkgArtifactId} ${pkgVersion} jar file.

There is a newer version: 0.2.20_1

Show newest version

/*
 * Distributed as part of mchange-commons-java 0.2.11
 *
 * Copyright (C) 2015 Machinery For Change, Inc.
 *
 * Author: Steve Waldman 
 *
 * 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.v1.util;

import java.util.Iterator;
import java.util.Map;


/**
 * @deprecated Oops! Doesn't conform to Map equals() / hashCode() contract!
 */
public final class MapUtils
{
    public static boolean equivalentDisregardingSort(Map a, Map b)
    {
	if (a.size() != b.size())
	    return false;

	for (Iterator ii = a.keySet().iterator(); ii.hasNext(); )
	    {
		Object key = ii.next();
		if (! a.get( key ).equals( b.get( key ) ))
		    return false;
	    }
	return true;
    }

    /**
     * finds a hash value which takes into account
     * the value of all elements, such that two maps
     * for which equivalentDisregardingSort(a, b) returns
     * true will hashContentsDisregardingSort() to the same value
     */
    public static int hashContentsDisregardingSort(Map m)
    {
	int out = 0;
	for (Iterator ii = m.keySet().iterator(); ii.hasNext(); )
	    {
		Object key = ii.next();
		Object val = m.get( key );
		out ^= (key.hashCode() ^ val.hashCode());
	    }
	return out;
    }
}