001/* AbstractListModel.java -- 002 Copyright (C) 2002, 2004, 2006, Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package javax.swing; 040 041import java.io.Serializable; 042import java.util.EventListener; 043 044import javax.swing.event.EventListenerList; 045import javax.swing.event.ListDataEvent; 046import javax.swing.event.ListDataListener; 047 048/** 049 * Provides standard implementations of some methods in {@link ListModel}. 050 * 051 * @author Ronald Veldema 052 * @author Andrew Selkirk 053 */ 054public abstract class AbstractListModel implements ListModel, Serializable 055{ 056 private static final long serialVersionUID = -3285184064379168730L; 057 058 /** List of ListDataListeners called for each change to the list. */ 059 protected EventListenerList listenerList; 060 061 /** 062 * Creates a new model instance - initialises the event listener list. 063 */ 064 public AbstractListModel() 065 { 066 listenerList = new EventListenerList(); 067 } 068 069 /** 070 * Add a listener object to this model. The listener will be called 071 * any time the set of elements in the model is changed. 072 * 073 * @param listener The listener to add 074 */ 075 public void addListDataListener(ListDataListener listener) 076 { 077 listenerList.add(ListDataListener.class, listener); 078 } 079 080 /** 081 * Add a listener object to this model. The listener will no longer be 082 * called when the set of elements in the model is changed. 083 * 084 * @param listener The listener to remove 085 */ 086 public void removeListDataListener(ListDataListener listener) 087 { 088 listenerList.remove(ListDataListener.class, listener); 089 } 090 091 /** 092 * Call {@link ListDataListener#contentsChanged} on each element of the 093 * {@link #listenerList} which is a {@link ListDataListener}. The event 094 * fired has type {@link ListDataEvent#CONTENTS_CHANGED} and represents a 095 * change to the data elements in the range [startIndex, endIndex] 096 * inclusive. 097 * 098 * @param source The source of the change, typically <code>this</code> 099 * @param startIndex The index of the first element which changed 100 * @param endIndex The index of the last element which changed 101 */ 102 protected void fireContentsChanged(Object source, int startIndex, 103 int endIndex) 104 { 105 ListDataEvent event = new ListDataEvent(source, ListDataEvent.CONTENTS_CHANGED, 106 startIndex, endIndex); 107 ListDataListener[] listeners = getListDataListeners(); 108 109 for (int index = 0; index < listeners.length; index++) 110 listeners[index].contentsChanged(event); 111 } 112 113 /** 114 * Call {@link ListDataListener#intervalAdded} on each element of the 115 * {@link #listenerList} which is a {@link ListDataListener}. The event 116 * fired has type {@link ListDataEvent#INTERVAL_ADDED} and represents an 117 * addition of the data elements in the range [startIndex, endIndex] 118 * inclusive. 119 * 120 * @param source The source of the change, typically <code>this</code> 121 * @param startIndex The index of the first new element 122 * @param endIndex The index of the last new element 123 */ 124 protected void fireIntervalAdded(Object source, int startIndex, int endIndex) 125 { 126 ListDataEvent event = 127 new ListDataEvent(source, ListDataEvent.INTERVAL_ADDED, 128 startIndex, endIndex); 129 ListDataListener[] listeners = getListDataListeners(); 130 131 for (int index = 0; index < listeners.length; index++) 132 listeners[index].intervalAdded(event); 133 } 134 135 /** 136 * Call {@link ListDataListener#intervalRemoved} on each element of the 137 * {@link #listenerList} which is a {@link ListDataListener}. The event 138 * fired has type {@link ListDataEvent#INTERVAL_REMOVED} and represents a 139 * removal of the data elements in the range [startIndex, endIndex] 140 * inclusive. 141 * 142 * @param source The source of the change, typically <code>this</code> 143 * @param startIndex The index of the first element removed 144 * @param endIndex The index of the last element removed 145 */ 146 protected void fireIntervalRemoved(Object source, int startIndex, 147 int endIndex) 148 { 149 ListDataEvent event = 150 new ListDataEvent(source, ListDataEvent.INTERVAL_REMOVED, 151 startIndex, endIndex); 152 ListDataListener[] listeners = getListDataListeners(); 153 154 for (int index = 0; index < listeners.length; index++) 155 listeners[index].intervalRemoved(event); 156 } 157 158 /** 159 * Return the subset of {@link EventListener} objects found in this 160 * object's {@link #listenerList} which are elements of the specified 161 * type. 162 * 163 * @param listenerType The type of listeners to select 164 * 165 * @return The set of listeners of the specified type 166 */ 167 public <T extends EventListener> T[] getListeners(Class<T> listenerType) 168 { 169 return listenerList.getListeners(listenerType); 170 } 171 172 /** 173 * A synonym for <code>getListeners(ListDataListener.class)</code>. 174 * 175 * @return The set of ListDataListeners found in the {@link #listenerList} 176 */ 177 public ListDataListener[] getListDataListeners() 178 { 179 return (ListDataListener[]) getListeners(ListDataListener.class); 180 } 181}