001    /* ===========================================================
002     * JFreeChart : a free chart library for the Java(tm) platform
003     * ===========================================================
004     *
005     * (C) Copyright 2000-2007, 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 2001-2007, 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     *
047     */
048    
049    package org.jfree.chart.labels;
050    
051    import java.io.Serializable;
052    
053    import org.jfree.data.time.RegularTimePeriod;
054    import org.jfree.data.time.TimeSeriesCollection;
055    import org.jfree.data.xy.XYDataset;
056    import org.jfree.data.xy.XisSymbolic;
057    import org.jfree.data.xy.YisSymbolic;
058    import org.jfree.util.PublicCloneable;
059    
060    /**
061     * A standard item label generator for plots that use data from an 
062     * {@link XYDataset}.
063     */
064    public class SymbolicXYItemLabelGenerator implements XYItemLabelGenerator, 
065                                                         XYToolTipGenerator,
066                                                         Cloneable, 
067                                                         PublicCloneable,
068                                                         Serializable {
069    
070        /** For serialization. */
071        private static final long serialVersionUID = 3963400354475494395L;
072        
073        /**
074         * Generates a tool tip text item for a particular item within a series.
075         *
076         * @param data  the dataset.
077         * @param series  the series number (zero-based index).
078         * @param item  the item number (zero-based index).
079         *
080         * @return The tool tip text (possibly <code>null</code>).
081         */
082        public String generateToolTip(XYDataset data, int series, int item) {
083    
084            String xStr, yStr;
085            if (data instanceof YisSymbolic) {
086                yStr = ((YisSymbolic) data).getYSymbolicValue(series, item);
087            }
088            else {
089                double y = data.getYValue(series, item);
090                yStr = Double.toString(round(y, 2));
091            }
092            if (data instanceof XisSymbolic) {
093                xStr = ((XisSymbolic) data).getXSymbolicValue(series, item);
094            }
095            else if (data instanceof TimeSeriesCollection) {
096                RegularTimePeriod p
097                    = ((TimeSeriesCollection) data).getSeries(series)
098                        .getTimePeriod(item);
099                xStr = p.toString();
100            }
101            else {
102                double x = data.getXValue(series, item);
103                xStr = Double.toString(round(x, 2));
104            }
105            return "X: " + xStr + ", Y: " + yStr;
106        }
107    
108        /**
109         * Generates a label for the specified item. The label is typically a 
110         * formatted version of the data value, but any text can be used.
111         *
112         * @param dataset  the dataset (<code>null</code> not permitted).
113         * @param series  the series index (zero-based).
114         * @param category  the category index (zero-based).
115         *
116         * @return The label (possibly <code>null</code>).
117         */
118        public String generateLabel(XYDataset dataset, int series, int category) {
119            return null;  //TODO: implement this method properly
120        }
121    
122        /**
123        * Round a double value.
124        *
125        * @param value  the value.
126        * @param nb  the exponent.
127        *
128        * @return The rounded value.
129        */
130        private static double round(double value, int nb) {
131            if (nb <= 0) {
132                return Math.floor(value + 0.5d);
133            }
134            double p = Math.pow(10, nb);
135            double tempval = Math.floor(value * p + 0.5d);
136            return tempval / p;
137        }
138        
139        /**
140         * Returns an independent copy of the generator.
141         * 
142         * @return A clone.
143         * 
144         * @throws CloneNotSupportedException if cloning is not supported.
145         */
146        public Object clone() throws CloneNotSupportedException { 
147            return super.clone();
148        }    
149    
150        /**
151         * Tests if this object is equal to another.
152         *
153         * @param obj  the other object.
154         *
155         * @return A boolean.
156         */
157        public boolean equals(Object obj) {
158            if (obj == this) {
159                return true;
160            }
161            if (obj instanceof SymbolicXYItemLabelGenerator) {
162                return true;
163            }
164            return false;
165        }
166        
167    }