001 /* ListModel.java --
002 Copyright (C) 2002, 2004 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038 package javax.swing;
039
040 import javax.swing.event.ListDataListener;
041
042 /**
043 * The data model that is typically used in {@link JList}.
044 *
045 * @author Graydon Hoare (graydon@redhat.com)
046 */
047 public interface ListModel
048 {
049 /**
050 * Return the number of data elements in the list.
051 *
052 * @return The number of data elements in the list
053 */
054 int getSize();
055
056 /**
057 * Retrieves a data element at a specified index.
058 *
059 * @param index The index of the element to retrieve
060 *
061 * @return The data element at the specified index
062 */
063 Object getElementAt(int index);
064
065 /**
066 * Add a listener object to this model. The listener will be called
067 * any time the set of elements in the model is changed.
068 *
069 * @param l The listener to add
070 */
071 void addListDataListener(ListDataListener l);
072
073 /**
074 * Add a listener object to this model. The listener will no longer be
075 * called when the set of elements in the model is changed.
076 *
077 * @param l The listener to remove
078 */
079 void removeListDataListener(ListDataListener l);
080 }