View Javadoc
1   /*
2    * Copyright (c) 1997, 2001, Oracle and/or its affiliates. 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.  Oracle designates this
8    * particular file as subject to the "Classpath" exception as provided
9    * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22   * or visit www.oracle.com if you need additional information or have any
23   * questions.
24   */
25  
26  package javax.swing;
27  
28  import javax.swing.event.ListDataListener;
29  
30  /**
31   * This interface defines the methods components like JList use
32   * to get the value of each cell in a list and the length of the list.
33   * Logically the model is a vector, indices vary from 0 to
34   * ListDataModel.getSize() - 1.  Any change to the contents or
35   * length of the data model must be reported to all of the
36   * ListDataListeners.
37   *
38   * @param <E> the type of the elements of this model
39   *
40   * @author Hans Muller
41   * @see JList
42   */
43  public interface ListModel<E>
44  {
45    /**
46     * Returns the length of the list.
47     * @return the length of the list
48     */
49    int getSize();
50  
51    /**
52     * Returns the value at the specified index.
53     * @param index the requested index
54     * @return the value at <code>index</code>
55     */
56    E getElementAt(int index);
57  
58    /**
59     * Adds a listener to the list that's notified each time a change
60     * to the data model occurs.
61     * @param l the <code>ListDataListener</code> to be added
62     */
63    void addListDataListener(ListDataListener l);
64  
65    /**
66     * Removes a listener from the list that's notified each time a
67     * change to the data model occurs.
68     * @param l the <code>ListDataListener</code> to be removed
69     */
70    void removeListDataListener(ListDataListener l);
71  }