    001    /* ===========================================================
    002     * JFreeChart : a free chart library for the Java(tm) platform
    003     * ===========================================================
    004     *
    005     * (C) Copyright 2000-2008, 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     * 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
    050    package 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     */
    063    public 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    }