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
26package javax.swing;
27
28import 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 * @since 1.2
43 */
44public interface ListModel<E>
45{
46  /**
47   * Returns the length of the list.
48   * @return the length of the list
49   */
50  int getSize();
51
52  /**
53   * Returns the value at the specified index.
54   * @param index the requested index
55   * @return the value at <code>index</code>
56   */
57  E getElementAt(int index);
58
59  /**
60   * Adds a listener to the list that's notified each time a change
61   * to the data model occurs.
62   * @param l the <code>ListDataListener</code> to be added
63   */
64  void addListDataListener(ListDataListener l);
65
66  /**
67   * Removes a listener from the list that's notified each time a
68   * change to the data model occurs.
69   * @param l the <code>ListDataListener</code> to be removed
70   */
71  void removeListDataListener(ListDataListener l);
72}
73