jaroslav@601: /*
jaroslav@601:  * Copyright (c) 2000, 2004, Oracle and/or its affiliates. All rights reserved.
jaroslav@601:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jaroslav@601:  *
jaroslav@601:  * This code is free software; you can redistribute it and/or modify it
jaroslav@601:  * under the terms of the GNU General Public License version 2 only, as
jaroslav@601:  * published by the Free Software Foundation.  Oracle designates this
jaroslav@601:  * particular file as subject to the "Classpath" exception as provided
jaroslav@601:  * by Oracle in the LICENSE file that accompanied this code.
jaroslav@601:  *
jaroslav@601:  * This code is distributed in the hope that it will be useful, but WITHOUT
jaroslav@601:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jaroslav@601:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jaroslav@601:  * version 2 for more details (a copy is included in the LICENSE file that
jaroslav@601:  * accompanied this code).
jaroslav@601:  *
jaroslav@601:  * You should have received a copy of the GNU General Public License version
jaroslav@601:  * 2 along with this work; if not, write to the Free Software Foundation,
jaroslav@601:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jaroslav@601:  *
jaroslav@601:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jaroslav@601:  * or visit www.oracle.com if you need additional information or have any
jaroslav@601:  * questions.
jaroslav@601:  */
jaroslav@601: 
jaroslav@601: package java.util;
jaroslav@601: 
jaroslav@601: /**
jaroslav@601:  * An abstract wrapper class for an {@code EventListener} class
jaroslav@601:  * which associates a set of additional parameters with the listener.
jaroslav@601:  * Subclasses must provide the storage and accessor methods
jaroslav@601:  * for the additional arguments or parameters.
jaroslav@601:  * <p>
jaroslav@601:  * For example, a bean which supports named properties
jaroslav@601:  * would have a two argument method signature for adding
jaroslav@601:  * a {@code PropertyChangeListener} for a property:
jaroslav@601:  * <pre>
jaroslav@601:  * public void addPropertyChangeListener(String propertyName,
jaroslav@601:  *                                       PropertyChangeListener listener)
jaroslav@601:  * </pre>
jaroslav@601:  * If the bean also implemented the zero argument get listener method:
jaroslav@601:  * <pre>
jaroslav@601:  * public PropertyChangeListener[] getPropertyChangeListeners()
jaroslav@601:  * </pre>
jaroslav@601:  * then the array may contain inner {@code PropertyChangeListeners}
jaroslav@601:  * which are also {@code PropertyChangeListenerProxy} objects.
jaroslav@601:  * <p>
jaroslav@601:  * If the calling method is interested in retrieving the named property
jaroslav@601:  * then it would have to test the element to see if it is a proxy class.
jaroslav@601:  *
jaroslav@601:  * @since 1.4
jaroslav@601:  */
jaroslav@601: public abstract class EventListenerProxy<T extends EventListener>
jaroslav@601:         implements EventListener {
jaroslav@601: 
jaroslav@601:     private final T listener;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Creates a proxy for the specified listener.
jaroslav@601:      *
jaroslav@601:      * @param listener  the listener object
jaroslav@601:      */
jaroslav@601:     public EventListenerProxy(T listener) {
jaroslav@601:         this.listener = listener;
jaroslav@601:     }
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Returns the listener associated with the proxy.
jaroslav@601:      *
jaroslav@601:      * @return  the listener associated with the proxy
jaroslav@601:      */
jaroslav@601:     public T getListener() {
jaroslav@601:         return this.listener;
jaroslav@601:     }
jaroslav@601: }