/*

 * Copyright (c) 2000, 2004, 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

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 */

package java.util;

/**

 * An abstract wrapper class for an {@code EventListener} class

 * which associates a set of additional parameters with the listener.

 * Subclasses must provide the storage and accessor methods

 * for the additional arguments or parameters.

 * <p>

 * For example, a bean which supports named properties

 * would have a two argument method signature for adding

 * a {@code PropertyChangeListener} for a property:

 * <pre>

 * public void addPropertyChangeListener(String propertyName,

 *                                       PropertyChangeListener listener)

 * </pre>

 * If the bean also implemented the zero argument get listener method:

 * <pre>

 * public PropertyChangeListener[] getPropertyChangeListeners()

 * </pre>

 * then the array may contain inner {@code PropertyChangeListeners}

 * which are also {@code PropertyChangeListenerProxy} objects.

 * <p>

 * If the calling method is interested in retrieving the named property

 * then it would have to test the element to see if it is a proxy class.

 *

 * @since 1.4

 */

public abstract class EventListenerProxy<T extends EventListener>

        implements EventListener {

    private final T listener;

    /**

     * Creates a proxy for the specified listener.

     *

     * @param listener  the listener object

     */

    public EventListenerProxy(T listener) {

        this.listener = listener;

    }

    /**

     * Returns the listener associated with the proxy.

     *

     * @return  the listener associated with the proxy

     */

    public T getListener() {

        return this.listener;

    }

}