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.table;
27
28 import javax.swing;
29 import javax.swing.event;
30 import java.io.Serializable;
31 import java.util.EventListener;
32
33 /**
34 * This abstract class provides default implementations for most of
35 * the methods in the <code>TableModel</code> interface. It takes care of
36 * the management of listeners and provides some conveniences for generating
37 * <code>TableModelEvents</code> and dispatching them to the listeners.
38 * To create a concrete <code>TableModel</code> as a subclass of
39 * <code>AbstractTableModel</code> you need only provide implementations
40 * for the following three methods:
41 *
42 * <pre>
43 * public int getRowCount();
44 * public int getColumnCount();
45 * public Object getValueAt(int row, int column);
46 * </pre>
47 * <p>
48 * <strong>Warning:</strong>
49 * Serialized objects of this class will not be compatible with
50 * future Swing releases. The current serialization support is
51 * appropriate for short term storage or RMI between applications running
52 * the same version of Swing. As of 1.4, support for long term storage
53 * of all JavaBeans<sup><font size="-2">TM</font></sup>
54 * has been added to the <code>java.beans</code> package.
55 * Please see {@link java.beans.XMLEncoder}.
56 *
57 * @author Alan Chung
58 * @author Philip Milne
59 */
60 public abstract class AbstractTableModel implements TableModel, Serializable
61 {
62 //
63 // Instance Variables
64 //
65
66 /** List of listeners */
67 protected EventListenerList listenerList = new EventListenerList();
68
69 //
70 // Default Implementation of the Interface
71 //
72
73 /**
74 * Returns a default name for the column using spreadsheet conventions:
75 * A, B, C, ... Z, AA, AB, etc. If <code>column</code> cannot be found,
76 * returns an empty string.
77 *
78 * @param column the column being queried
79 * @return a string containing the default name of <code>column</code>
80 */
81 public String getColumnName(int column) {
82 String result = "";
83 for (; column >= 0; column = column / 26 - 1) {
84 result = (char)((char)(column%26)+'A') + result;
85 }
86 return result;
87 }
88
89 /**
90 * Returns a column given its name.
91 * Implementation is naive so this should be overridden if
92 * this method is to be called often. This method is not
93 * in the <code>TableModel</code> interface and is not used by the
94 * <code>JTable</code>.
95 *
96 * @param columnName string containing name of column to be located
97 * @return the column with <code>columnName</code>, or -1 if not found
98 */
99 public int findColumn(String columnName) {
100 for (int i = 0; i < getColumnCount(); i++) {
101 if (columnName.equals(getColumnName(i))) {
102 return i;
103 }
104 }
105 return -1;
106 }
107
108 /**
109 * Returns <code>Object.class</code> regardless of <code>columnIndex</code>.
110 *
111 * @param columnIndex the column being queried
112 * @return the Object.class
113 */
114 public Class<?> getColumnClass(int columnIndex) {
115 return Object.class;
116 }
117
118 /**
119 * Returns false. This is the default implementation for all cells.
120 *
121 * @param rowIndex the row being queried
122 * @param columnIndex the column being queried
123 * @return false
124 */
125 public boolean isCellEditable(int rowIndex, int columnIndex) {
126 return false;
127 }
128
129 /**
130 * This empty implementation is provided so users don't have to implement
131 * this method if their data model is not editable.
132 *
133 * @param aValue value to assign to cell
134 * @param rowIndex row of cell
135 * @param columnIndex column of cell
136 */
137 public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
138 }
139
140
141 //
142 // Managing Listeners
143 //
144
145 /**
146 * Adds a listener to the list that's notified each time a change
147 * to the data model occurs.
148 *
149 * @param l the TableModelListener
150 */
151 public void addTableModelListener(TableModelListener l) {
152 listenerList.add(TableModelListener.class, l);
153 }
154
155 /**
156 * Removes a listener from the list that's notified each time a
157 * change to the data model occurs.
158 *
159 * @param l the TableModelListener
160 */
161 public void removeTableModelListener(TableModelListener l) {
162 listenerList.remove(TableModelListener.class, l);
163 }
164
165 /**
166 * Returns an array of all the table model listeners
167 * registered on this model.
168 *
169 * @return all of this model's <code>TableModelListener</code>s
170 * or an empty
171 * array if no table model listeners are currently registered
172 *
173 * @see #addTableModelListener
174 * @see #removeTableModelListener
175 *
176 * @since 1.4
177 */
178 public TableModelListener[] getTableModelListeners() {
179 return (TableModelListener[])listenerList.getListeners(
180 TableModelListener.class);
181 }
182
183 //
184 // Fire methods
185 //
186
187 /**
188 * Notifies all listeners that all cell values in the table's
189 * rows may have changed. The number of rows may also have changed
190 * and the <code>JTable</code> should redraw the
191 * table from scratch. The structure of the table (as in the order of the
192 * columns) is assumed to be the same.
193 *
194 * @see TableModelEvent
195 * @see EventListenerList
196 * @see javax.swing.JTable#tableChanged(TableModelEvent)
197 */
198 public void fireTableDataChanged() {
199 fireTableChanged(new TableModelEvent(this));
200 }
201
202 /**
203 * Notifies all listeners that the table's structure has changed.
204 * The number of columns in the table, and the names and types of
205 * the new columns may be different from the previous state.
206 * If the <code>JTable</code> receives this event and its
207 * <code>autoCreateColumnsFromModel</code>
208 * flag is set it discards any table columns that it had and reallocates
209 * default columns in the order they appear in the model. This is the
210 * same as calling <code>setModel(TableModel)</code> on the
211 * <code>JTable</code>.
212 *
213 * @see TableModelEvent
214 * @see EventListenerList
215 */
216 public void fireTableStructureChanged() {
217 fireTableChanged(new TableModelEvent(this, TableModelEvent.HEADER_ROW));
218 }
219
220 /**
221 * Notifies all listeners that rows in the range
222 * <code>[firstRow, lastRow]</code>, inclusive, have been inserted.
223 *
224 * @param firstRow the first row
225 * @param lastRow the last row
226 *
227 * @see TableModelEvent
228 * @see EventListenerList
229 *
230 */
231 public void fireTableRowsInserted(int firstRow, int lastRow) {
232 fireTableChanged(new TableModelEvent(this, firstRow, lastRow,
233 TableModelEvent.ALL_COLUMNS, TableModelEvent.INSERT));
234 }
235
236 /**
237 * Notifies all listeners that rows in the range
238 * <code>[firstRow, lastRow]</code>, inclusive, have been updated.
239 *
240 * @param firstRow the first row
241 * @param lastRow the last row
242 *
243 * @see TableModelEvent
244 * @see EventListenerList
245 */
246 public void fireTableRowsUpdated(int firstRow, int lastRow) {
247 fireTableChanged(new TableModelEvent(this, firstRow, lastRow,
248 TableModelEvent.ALL_COLUMNS, TableModelEvent.UPDATE));
249 }
250
251 /**
252 * Notifies all listeners that rows in the range
253 * <code>[firstRow, lastRow]</code>, inclusive, have been deleted.
254 *
255 * @param firstRow the first row
256 * @param lastRow the last row
257 *
258 * @see TableModelEvent
259 * @see EventListenerList
260 */
261 public void fireTableRowsDeleted(int firstRow, int lastRow) {
262 fireTableChanged(new TableModelEvent(this, firstRow, lastRow,
263 TableModelEvent.ALL_COLUMNS, TableModelEvent.DELETE));
264 }
265
266 /**
267 * Notifies all listeners that the value of the cell at
268 * <code>[row, column]</code> has been updated.
269 *
270 * @param row row of cell which has been updated
271 * @param column column of cell which has been updated
272 * @see TableModelEvent
273 * @see EventListenerList
274 */
275 public void fireTableCellUpdated(int row, int column) {
276 fireTableChanged(new TableModelEvent(this, row, row, column));
277 }
278
279 /**
280 * Forwards the given notification event to all
281 * <code>TableModelListeners</code> that registered
282 * themselves as listeners for this table model.
283 *
284 * @param e the event to be forwarded
285 *
286 * @see #addTableModelListener
287 * @see TableModelEvent
288 * @see EventListenerList
289 */
290 public void fireTableChanged(TableModelEvent e) {
291 // Guaranteed to return a non-null array
292 Object[] listeners = listenerList.getListenerList();
293 // Process the listeners last to first, notifying
294 // those that are interested in this event
295 for (int i = listeners.length-2; i>=0; i-=2) {
296 if (listeners[i]==TableModelListener.class) {
297 ((TableModelListener)listeners[i+1]).tableChanged(e);
298 }
299 }
300 }
301
302 /**
303 * Returns an array of all the objects currently registered
304 * as <code><em>Foo</em>Listener</code>s
305 * upon this <code>AbstractTableModel</code>.
306 * <code><em>Foo</em>Listener</code>s are registered using the
307 * <code>add<em>Foo</em>Listener</code> method.
308 *
309 * <p>
310 *
311 * You can specify the <code>listenerType</code> argument
312 * with a class literal,
313 * such as
314 * <code><em>Foo</em>Listener.class</code>.
315 * For example, you can query a
316 * model <code>m</code>
317 * for its table model listeners with the following code:
318 *
319 * <pre>TableModelListener[] tmls = (TableModelListener[])(m.getListeners(TableModelListener.class));</pre>
320 *
321 * If no such listeners exist, this method returns an empty array.
322 *
323 * @param listenerType the type of listeners requested; this parameter
324 * should specify an interface that descends from
325 * <code>java.util.EventListener</code>
326 * @return an array of all objects registered as
327 * <code><em>Foo</em>Listener</code>s on this component,
328 * or an empty array if no such
329 * listeners have been added
330 * @exception ClassCastException if <code>listenerType</code>
331 * doesn't specify a class or interface that implements
332 * <code>java.util.EventListener</code>
333 *
334 * @see #getTableModelListeners
335 *
336 * @since 1.3
337 */
338 public <T extends EventListener> T[] getListeners(Class<T> listenerType) {
339 return listenerList.getListeners(listenerType);
340 }
341 } // End of class AbstractTableModel
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