001 /* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jcommon/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * -----------------------
028 * SortableTableModel.java
029 * -----------------------
030 * (C) Copyright 2000-2005, by Object Refinery Limited;
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * $Id: SortableTableModel.java,v 1.6 2008/09/10 09:26:11 mungady Exp $
036 *
037 * Changes (from 26-Oct-2001)
038 * --------------------------
039 * 26-Oct-2001 : Changed package to com.jrefinery.ui.* (DG);
040 * 20-Nov-2001 : Made constructor protected (DG);
041 * 14-Oct-2002 : Fixed errors reported by Checkstyle (DG);
042 *
043 */
044
045 package org.jfree.ui;
046
047 import javax.swing.table.AbstractTableModel;
048
049 /**
050 * The base class for a sortable table model.
051 *
052 * @author David Gilbert
053 */
054 public abstract class SortableTableModel extends AbstractTableModel {
055
056 /** The column on which the data is sorted (-1 for no sorting). */
057 private int sortingColumn;
058
059 /** Indicates ascending (true) or descending (false) order. */
060 private boolean ascending;
061
062 /**
063 * Constructs a sortable table model.
064 */
065 public SortableTableModel() {
066 this.sortingColumn = -1;
067 this.ascending = true;
068 }
069
070 /**
071 * Returns the index of the sorting column, or -1 if the data is not sorted
072 * on any column.
073 *
074 * @return the column used for sorting.
075 */
076 public int getSortingColumn() {
077 return this.sortingColumn;
078 }
079
080 /**
081 * Returns <code>true</code> if the data is sorted in ascending order, and
082 * <code>false</code> otherwise.
083 *
084 * @return <code>true</code> if the data is sorted in ascending order, and
085 * <code>false</code> otherwise.
086 */
087 public boolean isAscending() {
088 return this.ascending;
089 }
090
091 /**
092 * Sets the flag that determines whether the sort order is ascending or
093 * descending.
094 *
095 * @param flag the flag.
096 */
097 public void setAscending(final boolean flag) {
098 this.ascending = flag;
099 }
100
101 /**
102 * Sorts the table.
103 *
104 * @param column the column to sort on (zero-based index).
105 * @param ascending a flag to indicate ascending order or descending order.
106 */
107 public void sortByColumn(final int column, final boolean ascending) {
108 if (isSortable(column)) {
109 this.sortingColumn = column;
110 }
111 }
112
113 /**
114 * Returns a flag indicating whether or not a column is sortable.
115 *
116 * @param column the column (zero-based index).
117 *
118 * @return boolean.
119 */
120 public boolean isSortable(final int column) {
121 return false;
122 }
123
124 }