001 /* 002 * Created on Mar 29, 2008 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with 005 * the License. You may obtain a copy of the License at 006 * 007 * http://www.apache.org/licenses/LICENSE-2.0 008 * 009 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on 010 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the 011 * specific language governing permissions and limitations under the License. 012 * 013 * Copyright @2008-2010 the original author or authors. 014 */ 015 package org.fest.swing.input; 016 017 import static org.fest.swing.listener.WeakEventListener.attachAsWeakEventListener; 018 019 import java.awt.AWTEvent; 020 import java.awt.Toolkit; 021 import java.awt.event.AWTEventListener; 022 023 import org.fest.swing.listener.WeakEventListener; 024 import org.fest.util.VisibleForTesting; 025 026 /** 027 * Understands an <code>{@link AWTEventListener}</code> which normalizes the event stream by sending a single 028 * <code>WINDOW_CLOSED</code>, instead of one every time dispose is called. 029 * 030 * @author Alex Ruiz 031 */ 032 public class EventNormalizer implements AWTEventListener { 033 034 private final DisposedWindowMonitor disposedWindowMonitor; 035 036 private WeakEventListener weakEventListener; 037 private AWTEventListener listener; 038 039 /** 040 * Creates a new </code>{@link EventNormalizer}</code>. 041 */ 042 public EventNormalizer() { 043 this(new DisposedWindowMonitor()); 044 } 045 046 @VisibleForTesting 047 EventNormalizer(DisposedWindowMonitor disposedWindowMonitor) { 048 this.disposedWindowMonitor = disposedWindowMonitor; 049 } 050 051 /** 052 * Starts listening for events. 053 * @param toolkit the <code>Toolkit</code> to use. 054 * @param delegate the event listener to delegate event processing to. 055 * @param mask the event mask to use to register this normalizer in the <code>Toolkit</code>. 056 */ 057 public void startListening(final Toolkit toolkit, AWTEventListener delegate, long mask) { 058 listener = delegate; 059 weakEventListener = attachAsWeakEventListener(toolkit, this, mask); 060 } 061 062 /** 063 * Stops listening for events and disposes the delegate event listener. 064 */ 065 public void stopListening() { 066 disposeWeakEventListener(); 067 listener = null; 068 } 069 070 private void disposeWeakEventListener() { 071 if (weakEventListener == null) return; 072 weakEventListener.dispose(); 073 weakEventListener = null; 074 } 075 076 /** 077 * Event reception callback. 078 * @param event the dispatached event. 079 */ 080 public void eventDispatched(AWTEvent event) { 081 boolean discard = disposedWindowMonitor.isDuplicateDispose(event); 082 if (!discard && listener != null) delegate(event); 083 } 084 085 private void delegate(AWTEvent e) { 086 listener.eventDispatched(e); 087 } 088 }