/*

 * Copyright (c) 2005, 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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 */

package com.sun.java.accessibility.util;

import java.awt.*;

import java.util.EventListener;

import javax.accessibility.*;

/**

 * The TopLevelWindowMulticaster class is used to maintain a list of

 * TopLevelWindowListener classes.  It is intended to be used primarily

 * for internal support in the EventQueueMonitor class, and is not intended

 * to be used by classes outside the Java Accessibility Utility package.

 *

 * @see EventQueueMonitor

 * @see EventQueueMonitor#addTopLevelWindowListener

 * @see EventQueueMonitor#removeTopLevelWindowListener

 *

 */

class TopLevelWindowMulticaster

    extends AWTEventMulticaster implements TopLevelWindowListener

{

    protected TopLevelWindowMulticaster(EventListener a, EventListener b) {

        super(a, b);

    }

    public void topLevelWindowCreated(Window w) {

        ((TopLevelWindowListener)a).topLevelWindowCreated(w);

        ((TopLevelWindowListener)b).topLevelWindowCreated(w);

    }

    public void topLevelWindowDestroyed(Window w) {

        ((TopLevelWindowListener)a).topLevelWindowDestroyed(w);

        ((TopLevelWindowListener)b).topLevelWindowDestroyed(w);

    }

    public static TopLevelWindowListener add(TopLevelWindowListener a, TopLevelWindowListener b) {

        return (TopLevelWindowListener)addInternal(a, b);

    }

    public static TopLevelWindowListener remove(TopLevelWindowListener l, TopLevelWindowListener oldl) {

        return (TopLevelWindowListener)removeInternal(l, oldl);

    }

    protected static EventListener addInternal(EventListener a, EventListener b) {

        if (a == null)  return b;

        if (b == null)  return a;

        return new TopLevelWindowMulticaster(a, b);

    }

    protected static EventListener removeInternal(EventListener l, EventListener oldl) {

        if (l == oldl || l == null) {

            return null;

        } else if (l instanceof TopLevelWindowMulticaster) {

            return ((TopLevelWindowMulticaster)l).remove(oldl);

        } else {

            return l;           // it's not here

        }

    }

}