001/* =========================================================== 002 * Orson Charts : a 3D chart library for the Java(tm) platform 003 * =========================================================== 004 * 005 * (C)opyright 2013-2022, by David Gilbert. All rights reserved. 006 * 007 * https://github.com/jfree/orson-charts 008 * 009 * This program is free software: you can redistribute it and/or modify 010 * it under the terms of the GNU General Public License as published by 011 * the Free Software Foundation, either version 3 of the License, or 012 * (at your option) any later version. 013 * 014 * This program is distributed in the hope that it will be useful, 015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 017 * GNU General Public License for more details. 018 * 019 * You should have received a copy of the GNU General Public License 020 * along with this program. If not, see <http://www.gnu.org/licenses/>. 021 * 022 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 023 * Other names may be trademarks of their respective owners.] 024 * 025 * If you do not wish to be bound by the terms of the GPL, an alternative 026 * commercial license can be purchased. For details, please see visit the 027 * Orson Charts home page: 028 * 029 * http://www.object-refinery.com/orsoncharts/index.html 030 * 031 */ 032 033package org.jfree.chart3d.data; 034 035import java.util.Arrays; 036import java.util.EventListener; 037import java.util.List; 038import javax.swing.event.EventListenerList; 039 040/** 041 * A base class that can be used to create new dataset classes. 042 */ 043public class AbstractDataset3D implements Dataset3D { 044 045 /** Storage for registered change listeners. */ 046 private final transient EventListenerList listenerList; 047 048 /** 049 * A flag that controls whether or not the dataset will notify listeners 050 * of changes (defaults to {@code true}, but sometimes it is useful 051 * to disable this). 052 */ 053 private boolean notify; 054 055 /** 056 * Default constructor - allocates storage for listeners that can 057 * be registered with the dataset. 058 */ 059 protected AbstractDataset3D() { 060 this.listenerList = new EventListenerList(); 061 this.notify = true; 062 } 063 064 /** 065 * Returns a flag that controls whether or not change events are sent to 066 * registered listeners. 067 * 068 * @return A boolean. 069 * 070 * @see #setNotify(boolean) 071 */ 072 public boolean isNotify() { 073 return this.notify; 074 } 075 076 /** 077 * Sets a flag that controls whether or not listeners receive 078 * {@link Dataset3DChangeEvent} notifications. 079 * 080 * @param notify a boolean. 081 * 082 * @see #isNotify() 083 */ 084 public void setNotify(boolean notify) { 085 this.notify = notify; 086 // if the flag is being set to true, there may be queued up changes... 087 if (notify) { 088 fireChangeEvent(); 089 } 090 } 091 092 /** 093 * Registers an object to receive notification of changes to the dataset. 094 * 095 * @param listener the object to register. 096 * 097 * @see #removeChangeListener(Dataset3DChangeListener) 098 */ 099 @Override 100 public void addChangeListener(Dataset3DChangeListener listener) { 101 this.listenerList.add(Dataset3DChangeListener.class, listener); 102 } 103 104 /** 105 * Deregisters an object so that it no longer receives notification of 106 * changes to the dataset. 107 * 108 * @param listener the object to deregister. 109 * 110 * @see #addChangeListener(Dataset3DChangeListener) 111 */ 112 @Override 113 public void removeChangeListener(Dataset3DChangeListener listener) { 114 this.listenerList.remove(Dataset3DChangeListener.class, listener); 115 } 116 117 /** 118 * Returns {@code true} if the specified object is registered with 119 * the dataset as a listener. Most applications won't need to call this 120 * method, it exists mainly for use by unit testing code. 121 * 122 * @param listener the listener. 123 * 124 * @return A boolean. 125 * 126 * @see #addChangeListener(Dataset3DChangeListener) 127 * @see #removeChangeListener(Dataset3DChangeListener) 128 */ 129 @Override 130 public boolean hasListener(EventListener listener) { 131 List<?> list = Arrays.asList(this.listenerList.getListenerList()); 132 return list.contains(listener); 133 } 134 135 /** 136 * Notifies all registered listeners that the dataset has changed. 137 * 138 * @see #addChangeListener(Dataset3DChangeListener) 139 */ 140 protected void fireDatasetChanged() { 141 notifyListeners(new Dataset3DChangeEvent(this, this)); 142 } 143 144 /** 145 * Notifies all registered listeners that the dataset has changed, unless 146 * the {@code notify} flag is set to {@code false} in which 147 * case this method does nothing. 148 * 149 * @param event contains information about the event that triggered the 150 * notification. 151 * 152 * @see #addChangeListener(Dataset3DChangeListener) 153 * @see #removeChangeListener(Dataset3DChangeListener) 154 */ 155 protected void notifyListeners(Dataset3DChangeEvent event) { 156 // if the 'notify' flag has been switched to false, we don't notify 157 // the listeners 158 if (!this.notify) { 159 return; 160 } 161 Object[] listeners = this.listenerList.getListenerList(); 162 for (int i = listeners.length - 2; i >= 0; i -= 2) { 163 if (listeners[i] == Dataset3DChangeListener.class) { 164 ((Dataset3DChangeListener) listeners[i + 1]) 165 .datasetChanged(event); 166 } 167 } 168 } 169 170 /** 171 * Sends a {@link Dataset3DChangeEvent} to all registered listeners, unless 172 * the {@code notify} flag is set to {@code false} in which 173 * case this method does nothing. 174 */ 175 protected void fireChangeEvent() { 176 notifyListeners(new Dataset3DChangeEvent(this, this)); 177 } 178 179}