| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /* $Id$ */ |
| |
| package org.apache.fop.events; |
| |
| import java.util.List; |
| |
| /** |
| * EventListener implementation forwards events to possibly multiple other EventListeners. |
| */ |
| public class CompositeEventListener implements EventListener { |
| |
| private List listeners = new java.util.ArrayList(); |
| |
| /** |
| * Adds an event listener to the broadcaster. It is appended to the list of previously |
| * registered listeners (the order of registration defines the calling order). |
| * @param listener the listener to be added |
| */ |
| public synchronized void addEventListener(EventListener listener) { |
| this.listeners.add(listener); |
| } |
| |
| /** |
| * Removes an event listener from the broadcaster. If the event listener is not registered, |
| * nothing happens. |
| * @param listener the listener to be removed |
| */ |
| public synchronized void removeEventListener(EventListener listener) { |
| this.listeners.remove(listener); |
| } |
| |
| private synchronized int getListenerCount() { |
| return this.listeners.size(); |
| } |
| |
| /** |
| * Indicates whether any listeners have been registered with the broadcaster. |
| * @return true if listeners are present, false otherwise |
| */ |
| public boolean hasEventListeners() { |
| return (getListenerCount() > 0); |
| } |
| |
| /** {@inheritDoc} */ |
| public synchronized void processEvent(Event event) { |
| for (int i = 0, c = getListenerCount(); i < c; i++) { |
| EventListener listener = (EventListener)this.listeners.get(i); |
| listener.processEvent(event); |
| } |
| } |
| |
| } |