/* * Copyright (c) 2000, 2004, Oracle and/or its affiliates. All rights reserved. * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. * * * * * * * * * * * * * * * * * * * * */ 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; } }