/* * This file is part of the GeoLatte project. * * GeoLatte is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * GeoLatte 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with GeoLatte. If not, see <http://www.gnu.org/licenses/>. * * Copyright (C) 2010 - 2010 and Ownership of code is shared by: * Qmino bvba - Romeinsestraat 18 - 3001 Heverlee (http://www.qmino.com) * Geovise bvba - Generaal Eisenhowerlei 9 - 2140 Antwerpen (http://www.geovise.com) */ package org.geolatte.common.transformer; import java.util.ArrayList; /** * <p> * Base class for transformer chains. A transformer chain can include a {@link TransformerSource}, a {@link Transformer} and {@link TransformerSink}, all of them optional. * This abstract class implements nothing more than the basic event mechanism for firing error events that might originate from a source, sink of a transformer. * </p> * <i>Creation-Date</i>: 04-May-2010<br> * <i>Creation-Time</i>: 14:54:50<br> * * * @author Bert Vanhooff * @author <a href="http://www.qmino.com">Qmino bvba</a> * @since SDK1.5 */ public abstract class TransformerChain<Source, Target> { private ArrayList<TransformerEventListener> transformerEventListeners = new ArrayList<TransformerEventListener>(); private ArrayList<TransformerSourceEventListener> transformerSourceEventListeners = new ArrayList<TransformerSourceEventListener>(); private ArrayList<TransformerSinkEventListener> transformerSinkEventListeners = new ArrayList<TransformerSinkEventListener>(); /** * Adds a listener for transformer events. Null listeners are ignored. * @param listener The listener to add */ public void addTransformerEventListener(TransformerEventListener listener) { if (listener != null) transformerEventListeners.add(listener); } /** * Removes the given listener. * @param listener The listener to remove. */ public void removeTransformerEventListener(TransformerEventListener listener) { transformerEventListeners.remove(listener); } /** * (Re)-fires the given event * @param event A pre-constructed event. */ protected void onTransformerErrorOccurred(TransformerErrorEvent event) { for (TransformerEventListener listener : transformerEventListeners) fireTransformerErrorEvent(listener, event); } /** * Helper method that fires the given event on the given listener. * @param listener The listener to fire the event on. * @param event The event to fire. */ private void fireTransformerErrorEvent(TransformerEventListener listener, TransformerErrorEvent event) { try { listener.ErrorOccurred(event); } catch (RuntimeException e) { // Log this somehow System.err.println("Exception thrown while trying to invoke event listener, removing bed behaved listener."); e.printStackTrace(); removeTransformerEventListener(listener); } } public void addSourceEventListener(TransformerSourceEventListener listener) { if (listener != null) transformerSourceEventListeners.add(listener); } public void removeSourceEventListener(TransformerSourceEventListener listener) { transformerSourceEventListeners.remove(listener); } /** * (Re)-fires the given event * @param event The event to fire. */ protected void onTransformerSourceErrorOccurred(TransformerSourceErrorEvent event) { for (TransformerSourceEventListener listener : transformerSourceEventListeners) fireTransformerSourceErrorEvent(listener, event); } /** * Helper method that fires the given event on the given listener. * @param listener The listener to fire the event on. * @param event The event to fire. */ private void fireTransformerSourceErrorEvent(TransformerSourceEventListener listener, TransformerSourceErrorEvent event) { try { listener.ErrorOccurred(event); } catch (RuntimeException e) { // Log this somehow System.err.println("Exception thrown while trying to invoke event listener, removing bed behaved listener."); e.printStackTrace(); removeSourceEventListener(listener); } } public void addSinkEventListener(TransformerSinkEventListener listener) { if (listener != null) transformerSinkEventListeners.add(listener); } public void removeSinkEventListener(TransformerSinkEventListener listener) { transformerSinkEventListeners.remove(listener); } /** * (Re)-fires the given event * @param event The event to fire. */ protected void onTransformerSinkErrorOccurred(TransformerSinkErrorEvent event) { for (TransformerSinkEventListener listener : transformerSinkEventListeners) fireTransformerSinkErrorEvent(listener, event); } private void fireTransformerSinkErrorEvent(TransformerSinkEventListener listener, TransformerSinkErrorEvent event) { try { listener.ErrorOccurred(event); } catch (RuntimeException e) { // Log this somehow System.err.println("Exception thrown while trying to invoke event listener, removing bad behaved listener."); e.printStackTrace(); removeSinkEventListener(listener); } } }