    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     * SymbolicXYItemLabelGenerator.java
    029     * ---------------------------------
    030     * (C) Copyright 2001-2008, by Anthony Boulestreau and Contributors.
    031     *
    032     * Original Author:  Anthony Boulestreau;
    033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
    034     *
    035     * Changes
    036     * -------
    037     * 29-Mar-2002 : Version 1, contributed by Anthony Boulestreau (DG);
    038     * 26-Sep-2002 : Fixed errors reported by Checkstyle (DG);
    039     * 23-Mar-2003 : Implemented Serializable (DG);
    040     * 13-Aug-2003 : Implemented Cloneable (DG);
    041     * 17-Nov-2003 : Implemented PublicCloneable (DG);
    042     * 25-Feb-2004 : Renamed XYToolTipGenerator --> XYItemLabelGenerator (DG);
    043     * 19-Jan-2005 : Now accesses primitives only from dataset (DG);
    044     * 20-Apr-2005 : Renamed XYLabelGenerator --> XYItemLabelGenerator (DG);
    045     * 02-Feb-2007 : Removed author tags all over JFreeChart sources (DG);
    046     * 31-Mar-2008 : Added hashCode() method to appease FindBugs (DG);
    047     *
    048     */
    049
    050    package org.jfree.chart.labels;
    051
    052    import java.io.Serializable;
    053
    054    import org.jfree.data.time.RegularTimePeriod;
    055    import org.jfree.data.time.TimeSeriesCollection;
    056    import org.jfree.data.xy.XYDataset;
    057    import org.jfree.data.xy.XisSymbolic;
    058    import org.jfree.data.xy.YisSymbolic;
    059    import org.jfree.util.PublicCloneable;
    060
    061    /**
    062     * A standard item label generator for plots that use data from an
    063     * {@link XYDataset}.
    064     */
    065    public class SymbolicXYItemLabelGenerator implements XYItemLabelGenerator,
    066            XYToolTipGenerator, Cloneable, PublicCloneable, Serializable {
    067
    068        /** For serialization. */
    069        private static final long serialVersionUID = 3963400354475494395L;
    070
    071        /**
    072         * Generates a tool tip text item for a particular item within a series.
    073         *
    074         * @param data  the dataset.
    075         * @param series  the series number (zero-based index).
    076         * @param item  the item number (zero-based index).
    077         *
    078         * @return The tool tip text (possibly <code>null</code>).
    079         */
    080        public String generateToolTip(XYDataset data, int series, int item) {
    081
    082            String xStr, yStr;
    083            if (data instanceof YisSymbolic) {
    084                yStr = ((YisSymbolic) data).getYSymbolicValue(series, item);
    085            }
    086            else {
    087                double y = data.getYValue(series, item);
    088                yStr = Double.toString(round(y, 2));
    089            }
    090            if (data instanceof XisSymbolic) {
    091                xStr = ((XisSymbolic) data).getXSymbolicValue(series, item);
    092            }
    093            else if (data instanceof TimeSeriesCollection) {
    094                RegularTimePeriod p
    095                    = ((TimeSeriesCollection) data).getSeries(series)
    096                        .getTimePeriod(item);
    097                xStr = p.toString();
    098            }
    099            else {
    100                double x = data.getXValue(series, item);
    101                xStr = Double.toString(round(x, 2));
    102            }
    103            return "X: " + xStr + ", Y: " + yStr;
    104        }
    105
    106        /**
    107         * Generates a label for the specified item. The label is typically a
    108         * formatted version of the data value, but any text can be used.
    109         *
    110         * @param dataset  the dataset (<code>null</code> not permitted).
    111         * @param series  the series index (zero-based).
    112         * @param category  the category index (zero-based).
    113         *
    114         * @return The label (possibly <code>null</code>).
    115         */
    116        public String generateLabel(XYDataset dataset, int series, int category) {
    117            return null;  //TODO: implement this method properly
    118        }
    119
    120        /**
    121        * Round a double value.
    122        *
    123        * @param value  the value.
    124        * @param nb  the exponent.
    125        *
    126        * @return The rounded value.
    127        */
    128        private static double round(double value, int nb) {
    129            if (nb <= 0) {
    130                return Math.floor(value + 0.5d);
    131            }
    132            double p = Math.pow(10, nb);
    133            double tempval = Math.floor(value * p + 0.5d);
    134            return tempval / p;
    135        }
    136
    137        /**
    138         * Returns an independent copy of the generator.
    139         *
    140         * @return A clone.
    141         *
    142         * @throws CloneNotSupportedException if cloning is not supported.
    143         */
    144        public Object clone() throws CloneNotSupportedException {
    145            return super.clone();
    146        }
    147
    148        /**
    149         * Tests if this object is equal to another.
    150         *
    151         * @param obj  the other object.
    152         *
    153         * @return A boolean.
    154         */
    155        public boolean equals(Object obj) {
    156            if (obj == this) {
    157                return true;
    158            }
    159            if (obj instanceof SymbolicXYItemLabelGenerator) {
    160                return true;
    161            }
    162            return false;
    163        }
    164
    165        /**
    166         * Returns a hash code for this instance.
    167         *
    168         * @return A hash code.
    169         */
    170        public int hashCode() {
    171            int result = 127;
    172            return result;
    173        }
    174
    175    }