    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, 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 * 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
    050package org.jfree.chart.labels;
    051
    052import java.io.Serializable;
    053
    054import org.jfree.data.time.RegularTimePeriod;
    055import org.jfree.data.time.TimeSeriesCollection;
    056import org.jfree.data.xy.XYDataset;
    057import org.jfree.data.xy.XisSymbolic;
    058import org.jfree.data.xy.YisSymbolic;
    059import org.jfree.util.PublicCloneable;
    060
    061/**
    062 * A standard item label generator for plots that use data from an
    063 * {@link XYDataset}.
    064 */
    065public 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}