Source for org.jfree.data.general.DatasetChangeEvent

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
   6:  *
   7:  * Project Info:  http://www.jfree.org/jfreechart/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it 
  10:  * under the terms of the GNU Lesser General Public License as published by 
  11:  * the Free Software Foundation; either version 2.1 of the License, or 
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but 
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
  22:  * USA.  
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
  25:  * in the United States and other countries.]
  26:  *
  27:  * -----------------------
  28:  * DatasetChangeEvent.java
  29:  * -----------------------
  30:  * (C) Copyright 2000-2007, by Object Refinery Limited.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * Changes (from 24-Aug-2001)
  36:  * --------------------------
  37:  * 24-Aug-2001 : Added standard source header. Fixed DOS encoding problem (DG);
  38:  * 15-Oct-2001 : Move to new package (com.jrefinery.data.*) (DG);
  39:  * 22-Oct-2001 : Renamed DataSource.java --> Dataset.java etc. (DG);
  40:  * 11-Jun-2002 : Separated the event source from the dataset to cover the case 
  41:  *               where the dataset is changed to null in the Plot class.  
  42:  *               Updated Javadocs (DG);
  43:  * 04-Oct-2002 : Fixed errors reported by Checkstyle (DG);
  44:  * 05-Oct-2004 : Minor Javadoc updates (DG);
  45:  *
  46:  */
  47: 
  48: package org.jfree.data.general;
  49: 
  50: /**
  51:  * A change event that encapsulates information about a change to a dataset.
  52:  */
  53: public class DatasetChangeEvent extends java.util.EventObject {
  54: 
  55:     /**
  56:      * The dataset that generated the change event.
  57:      */
  58:     private Dataset dataset;
  59: 
  60:     /**
  61:      * Constructs a new event.  The source is either the dataset or the 
  62:      * {@link org.jfree.chart.plot.Plot} class.  The dataset can be 
  63:      * <code>null</code> (in this case the source will be the 
  64:      * {@link org.jfree.chart.plot.Plot} class).
  65:      *
  66:      * @param source  the source of the event.
  67:      * @param dataset  the dataset that generated the event (<code>null</code>
  68:      *                 permitted).
  69:      */
  70:     public DatasetChangeEvent(Object source, Dataset dataset) {
  71:         super(source);
  72:         this.dataset = dataset;
  73:     }
  74: 
  75:     /**
  76:      * Returns the dataset that generated the event.  Note that the dataset
  77:      * may be <code>null</code> since adding a <code>null</code> dataset to a 
  78:      * plot will generated a change event.
  79:      *
  80:      * @return The dataset (possibly <code>null</code>).
  81:      */
  82:     public Dataset getDataset() {
  83:         return this.dataset;
  84:     }
  85: 
  86: }