001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jfreechart/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 * PlotUtilities.java
029 * ------------------
030 * (C) Copyright 2007, by Sergei Ivanov and Contributors.
031 *
032 * Original Author: Sergei Ivanov;
033 * Contributor(s): David Gilbert (for Object Refinery Limited);
034 *
035 * Changes
036 * -------
037 * 26-Sep-2007 : Version 1, contributed by Sergei Ivanov (see patch
038 * 1772932) (DG);
039 *
040 */
041
042 package org.jfree.chart.plot;
043
044 import org.jfree.data.general.DatasetUtilities;
045 import org.jfree.data.xy.XYDataset;
046
047 /**
048 * Some utility methods related to the plot classes.
049 *
050 * @since 1.0.7
051 */
052 public class PlotUtilities {
053
054 /**
055 * Returns <code>true</code> if all the datasets belonging to the specified
056 * plot are empty or <code>null</code>, and <code>false</code> otherwise.
057 *
058 * @param plot the plot (<code>null</code> permitted).
059 *
060 * @return A boolean.
061 *
062 * @since 1.0.7
063 */
064 public static boolean isEmptyOrNull(XYPlot plot) {
065 if (plot != null) {
066 for (int i = 0, n = plot.getDatasetCount(); i < n; i++) {
067 final XYDataset dataset = plot.getDataset(i);
068 if (!DatasetUtilities.isEmptyOrNull(dataset)) {
069 return false;
070 }
071 }
072 }
073 return true;
074 }
075
076 }