001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2020, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * ------------
028 * Dataset.java
029 * ------------
030 * (C) Copyright 2000-2008, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes (from 18-Sep-2001)
036 * --------------------------
037 * 18-Sep-2001 : Added standard header and fixed DOS encoding problem (DG);
038 * 15-Oct-2001 : Moved to a new package (com.jrefinery.data.*) (DG);
039 * 22-Oct-2001 : Changed name to Dataset.java (DG);
040 * 17-Nov-2001 : Added getLegendItemCount() and getLegendItemLabels() methods,
041 *               created SeriesDataset interface and transferred series related
042 *               methods out (DG);
043 * 22-Jan-2002 : Reconsidered (and removed) the getLegendItemCount() and
044 *               getLegendItemLabels() methods...leave this to client code (DG);
045 * 27-Sep-2002 : Added get/setDatasetGroup() methods (DG);
046 * 10-Jan-2003 : Updated Javadocs (DG);
047 *
048 */
049
050package org.jfree.data.general;
051
052/**
053 * The base interface for data sets.
054 * <P>
055 * All datasets are required to support the {@link DatasetChangeEvent}
056 * mechanism by allowing listeners to register and receive notification of any
057 * changes to the dataset.
058 * <P>
059 * In addition, all datasets must belong to one (and only one)
060 * {@link DatasetGroup}.  The group object maintains a reader-writer lock
061 * which provides synchronised access to the datasets in multi-threaded code.
062 */
063public interface Dataset {
064
065    /**
066     * Registers an object for notification of changes to the dataset.
067     *
068     * @param listener  the object to register.
069     */
070    public void addChangeListener(DatasetChangeListener listener);
071
072    /**
073     * Deregisters an object for notification of changes to the dataset.
074     *
075     * @param listener  the object to deregister.
076     */
077    public void removeChangeListener(DatasetChangeListener listener);
078
079    /**
080     * Returns the dataset group.
081     *
082     * @return The dataset group.
083     */
084    public DatasetGroup getGroup();
085
086    /**
087     * Sets the dataset group.
088     *
089     * @param group  the dataset group.
090     */
091    public void setGroup(DatasetGroup group);
092
093}