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     * $Id: SymbolicXYItemLabelGenerator.java,v 1.5.2.2 2007/02/02 15:52:42 mungady Exp $
036     * 
037     * Changes
038     * -------
039     * 29-Mar-2002 : Version 1, contributed by Anthony Boulestreau (DG);
040     * 26-Sep-2002 : Fixed errors reported by Checkstyle (DG);
041     * 23-Mar-2003 : Implemented Serializable (DG);
042     * 13-Aug-2003 : Implemented Cloneable (DG);
043     * 17-Nov-2003 : Implemented PublicCloneable (DG);
044     * 25-Feb-2004 : Renamed XYToolTipGenerator --> XYItemLabelGenerator (DG);
045     * 19-Jan-2005 : Now accesses primitives only from dataset (DG);
046     * 20-Apr-2005 : Renamed XYLabelGenerator --> XYItemLabelGenerator (DG);
047     * 02-Feb-2007 : Removed author tags all over JFreeChart sources (DG);
048     *
049     */
050    
051    package org.jfree.chart.labels;
052    
053    import java.io.Serializable;
054    
055    import org.jfree.data.time.RegularTimePeriod;
056    import org.jfree.data.time.TimeSeriesCollection;
057    import org.jfree.data.xy.XYDataset;
058    import org.jfree.data.xy.XisSymbolic;
059    import org.jfree.data.xy.YisSymbolic;
060    import org.jfree.util.PublicCloneable;
061    
062    /**
063     * A standard item label generator for plots that use data from an 
064     * {@link XYDataset}.
065     */
066    public class SymbolicXYItemLabelGenerator implements XYItemLabelGenerator, 
067                                                         XYToolTipGenerator,
068                                                         Cloneable, 
069                                                         PublicCloneable,
070                                                         Serializable {
071    
072        /** For serialization. */
073        private static final long serialVersionUID = 3963400354475494395L;
074        
075        /**
076         * Generates a tool tip text item for a particular item within a series.
077         *
078         * @param data  the dataset.
079         * @param series  the series number (zero-based index).
080         * @param item  the item number (zero-based index).
081         *
082         * @return The tool tip text (possibly <code>null</code>).
083         */
084        public String generateToolTip(XYDataset data, int series, int item) {
085    
086            String xStr, yStr;
087            if (data instanceof YisSymbolic) {
088                yStr = ((YisSymbolic) data).getYSymbolicValue(series, item);
089            }
090            else {
091                double y = data.getYValue(series, item);
092                yStr = Double.toString(round(y, 2));
093            }
094            if (data instanceof XisSymbolic) {
095                xStr = ((XisSymbolic) data).getXSymbolicValue(series, item);
096            }
097            else if (data instanceof TimeSeriesCollection) {
098                RegularTimePeriod p
099                    = ((TimeSeriesCollection) data).getSeries(series)
100                        .getTimePeriod(item);
101                xStr = p.toString();
102            }
103            else {
104                double x = data.getXValue(series, item);
105                xStr = Double.toString(round(x, 2));
106            }
107            return "X: " + xStr + ", Y: " + yStr;
108        }
109    
110        /**
111         * Generates a label for the specified item. The label is typically a 
112         * formatted version of the data value, but any text can be used.
113         *
114         * @param dataset  the dataset (<code>null</code> not permitted).
115         * @param series  the series index (zero-based).
116         * @param category  the category index (zero-based).
117         *
118         * @return The label (possibly <code>null</code>).
119         */
120        public String generateLabel(XYDataset dataset, int series, int category) {
121            return null;  //TODO: implement this method properly
122        }
123    
124        /**
125        * Round a double value.
126        *
127        * @param value  the value.
128        * @param nb  the exponent.
129        *
130        * @return The rounded value.
131        */
132        private static double round(double value, int nb) {
133            if (nb <= 0) {
134                return Math.floor(value + 0.5d);
135            }
136            double p = Math.pow(10, nb);
137            double tempval = Math.floor(value * p + 0.5d);
138            return tempval / p;
139        }
140        
141        /**
142         * Returns an independent copy of the generator.
143         * 
144         * @return A clone.
145         * 
146         * @throws CloneNotSupportedException if cloning is not supported.
147         */
148        public Object clone() throws CloneNotSupportedException { 
149            return super.clone();
150        }    
151    
152        /**
153         * Tests if this object is equal to another.
154         *
155         * @param obj  the other object.
156         *
157         * @return A boolean.
158         */
159        public boolean equals(Object obj) {
160            if (obj == this) {
161                return true;
162            }
163            if (obj instanceof SymbolicXYItemLabelGenerator) {
164                return true;
165            }
166            return false;
167        }
168        
169    }