J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1997-2004 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package javax.swing; |
| 27 | |
| 28 | import javax.swing.event.*; |
| 29 | import java.io.Serializable; |
| 30 | import java.util.EventListener; |
| 31 | |
| 32 | /** |
| 33 | * The abstract definition for the data model that provides |
| 34 | * a <code>List</code> with its contents. |
| 35 | * <p> |
| 36 | * <strong>Warning:</strong> |
| 37 | * Serialized objects of this class will not be compatible with |
| 38 | * future Swing releases. The current serialization support is |
| 39 | * appropriate for short term storage or RMI between applications running |
| 40 | * the same version of Swing. As of 1.4, support for long term storage |
| 41 | * of all JavaBeans<sup><font size="-2">TM</font></sup> |
| 42 | * has been added to the <code>java.beans</code> package. |
| 43 | * Please see {@link java.beans.XMLEncoder}. |
| 44 | * |
| 45 | * @author Hans Muller |
| 46 | */ |
| 47 | public abstract class AbstractListModel implements ListModel, Serializable |
| 48 | { |
| 49 | protected EventListenerList listenerList = new EventListenerList(); |
| 50 | |
| 51 | |
| 52 | /** |
| 53 | * Adds a listener to the list that's notified each time a change |
| 54 | * to the data model occurs. |
| 55 | * |
| 56 | * @param l the <code>ListDataListener</code> to be added |
| 57 | */ |
| 58 | public void addListDataListener(ListDataListener l) { |
| 59 | listenerList.add(ListDataListener.class, l); |
| 60 | } |
| 61 | |
| 62 | |
| 63 | /** |
| 64 | * Removes a listener from the list that's notified each time a |
| 65 | * change to the data model occurs. |
| 66 | * |
| 67 | * @param l the <code>ListDataListener</code> to be removed |
| 68 | */ |
| 69 | public void removeListDataListener(ListDataListener l) { |
| 70 | listenerList.remove(ListDataListener.class, l); |
| 71 | } |
| 72 | |
| 73 | |
| 74 | /** |
| 75 | * Returns an array of all the list data listeners |
| 76 | * registered on this <code>AbstractListModel</code>. |
| 77 | * |
| 78 | * @return all of this model's <code>ListDataListener</code>s, |
| 79 | * or an empty array if no list data listeners |
| 80 | * are currently registered |
| 81 | * |
| 82 | * @see #addListDataListener |
| 83 | * @see #removeListDataListener |
| 84 | * |
| 85 | * @since 1.4 |
| 86 | */ |
| 87 | public ListDataListener[] getListDataListeners() { |
| 88 | return (ListDataListener[])listenerList.getListeners( |
| 89 | ListDataListener.class); |
| 90 | } |
| 91 | |
| 92 | |
| 93 | /** |
| 94 | * <code>AbstractListModel</code> subclasses must call this method |
| 95 | * <b>after</b> |
| 96 | * one or more elements of the list change. The changed elements |
| 97 | * are specified by the closed interval index0, index1 -- the endpoints |
| 98 | * are included. Note that |
| 99 | * index0 need not be less than or equal to index1. |
| 100 | * |
| 101 | * @param source the <code>ListModel</code> that changed, typically "this" |
| 102 | * @param index0 one end of the new interval |
| 103 | * @param index1 the other end of the new interval |
| 104 | * @see EventListenerList |
| 105 | * @see DefaultListModel |
| 106 | */ |
| 107 | protected void fireContentsChanged(Object source, int index0, int index1) |
| 108 | { |
| 109 | Object[] listeners = listenerList.getListenerList(); |
| 110 | ListDataEvent e = null; |
| 111 | |
| 112 | for (int i = listeners.length - 2; i >= 0; i -= 2) { |
| 113 | if (listeners[i] == ListDataListener.class) { |
| 114 | if (e == null) { |
| 115 | e = new ListDataEvent(source, ListDataEvent.CONTENTS_CHANGED, index0, index1); |
| 116 | } |
| 117 | ((ListDataListener)listeners[i+1]).contentsChanged(e); |
| 118 | } |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | |
| 123 | /** |
| 124 | * <code>AbstractListModel</code> subclasses must call this method |
| 125 | * <b>after</b> |
| 126 | * one or more elements are added to the model. The new elements |
| 127 | * are specified by a closed interval index0, index1 -- the enpoints |
| 128 | * are included. Note that |
| 129 | * index0 need not be less than or equal to index1. |
| 130 | * |
| 131 | * @param source the <code>ListModel</code> that changed, typically "this" |
| 132 | * @param index0 one end of the new interval |
| 133 | * @param index1 the other end of the new interval |
| 134 | * @see EventListenerList |
| 135 | * @see DefaultListModel |
| 136 | */ |
| 137 | protected void fireIntervalAdded(Object source, int index0, int index1) |
| 138 | { |
| 139 | Object[] listeners = listenerList.getListenerList(); |
| 140 | ListDataEvent e = null; |
| 141 | |
| 142 | for (int i = listeners.length - 2; i >= 0; i -= 2) { |
| 143 | if (listeners[i] == ListDataListener.class) { |
| 144 | if (e == null) { |
| 145 | e = new ListDataEvent(source, ListDataEvent.INTERVAL_ADDED, index0, index1); |
| 146 | } |
| 147 | ((ListDataListener)listeners[i+1]).intervalAdded(e); |
| 148 | } |
| 149 | } |
| 150 | } |
| 151 | |
| 152 | |
| 153 | /** |
| 154 | * <code>AbstractListModel</code> subclasses must call this method |
| 155 | * <b>after</b> one or more elements are removed from the model. |
| 156 | * <code>index0</code> and <code>index1</code> are the end points |
| 157 | * of the interval that's been removed. Note that <code>index0</code> |
| 158 | * need not be less than or equal to <code>index1</code>. |
| 159 | * |
| 160 | * @param source the <code>ListModel</code> that changed, typically "this" |
| 161 | * @param index0 one end of the removed interval, |
| 162 | * including <code>index0</code> |
| 163 | * @param index1 the other end of the removed interval, |
| 164 | * including <code>index1</code> |
| 165 | * @see EventListenerList |
| 166 | * @see DefaultListModel |
| 167 | */ |
| 168 | protected void fireIntervalRemoved(Object source, int index0, int index1) |
| 169 | { |
| 170 | Object[] listeners = listenerList.getListenerList(); |
| 171 | ListDataEvent e = null; |
| 172 | |
| 173 | for (int i = listeners.length - 2; i >= 0; i -= 2) { |
| 174 | if (listeners[i] == ListDataListener.class) { |
| 175 | if (e == null) { |
| 176 | e = new ListDataEvent(source, ListDataEvent.INTERVAL_REMOVED, index0, index1); |
| 177 | } |
| 178 | ((ListDataListener)listeners[i+1]).intervalRemoved(e); |
| 179 | } |
| 180 | } |
| 181 | } |
| 182 | |
| 183 | /** |
| 184 | * Returns an array of all the objects currently registered as |
| 185 | * <code><em>Foo</em>Listener</code>s |
| 186 | * upon this model. |
| 187 | * <code><em>Foo</em>Listener</code>s |
| 188 | * are registered using the <code>add<em>Foo</em>Listener</code> method. |
| 189 | * <p> |
| 190 | * You can specify the <code>listenerType</code> argument |
| 191 | * with a class literal, such as <code><em>Foo</em>Listener.class</code>. |
| 192 | * For example, you can query a list model |
| 193 | * <code>m</code> |
| 194 | * for its list data listeners |
| 195 | * with the following code: |
| 196 | * |
| 197 | * <pre>ListDataListener[] ldls = (ListDataListener[])(m.getListeners(ListDataListener.class));</pre> |
| 198 | * |
| 199 | * If no such listeners exist, |
| 200 | * this method returns an empty array. |
| 201 | * |
| 202 | * @param listenerType the type of listeners requested; |
| 203 | * this parameter should specify an interface |
| 204 | * that descends from <code>java.util.EventListener</code> |
| 205 | * @return an array of all objects registered as |
| 206 | * <code><em>Foo</em>Listener</code>s |
| 207 | * on this model, |
| 208 | * or an empty array if no such |
| 209 | * listeners have been added |
| 210 | * @exception ClassCastException if <code>listenerType</code> doesn't |
| 211 | * specify a class or interface that implements |
| 212 | * <code>java.util.EventListener</code> |
| 213 | * |
| 214 | * @see #getListDataListeners |
| 215 | * |
| 216 | * @since 1.3 |
| 217 | */ |
| 218 | public <T extends EventListener> T[] getListeners(Class<T> listenerType) { |
| 219 | return listenerList.getListeners(listenerType); |
| 220 | } |
| 221 | } |