Source for org.jfree.chart.labels.AbstractPieItemLabelGenerator

   1: /* ===========================================================
   2:  * JFreeChart : a free chart library for the Java(tm) platform
   3:  * ===========================================================
   4:  *
   5:  * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
   6:  *
   7:  * Project Info:  http://www.jfree.org/jfreechart/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it 
  10:  * under the terms of the GNU Lesser General Public License as published by 
  11:  * the Free Software Foundation; either version 2.1 of the License, or 
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but 
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
  22:  * USA.  
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
  25:  * in the United States and other countries.]
  26:  *
  27:  * ----------------------------------
  28:  * AbstractPieItemLabelGenerator.java
  29:  * ----------------------------------
  30:  * (C) Copyright 2004-2007, by Object Refinery Limited.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * Changes
  36:  * -------
  37:  * 09-Nov-2004 : Version 1, draws out code from StandardPieItemLabelGenerator 
  38:  *               and StandardPieToolTipGenerator (DG);
  39:  * ------------- JFREECHART 1.0.x ---------------------------------------------
  40:  * 03-May-2006 : Fixed bug 1480978, a problem in the clone() method (DG);
  41:  * 23-Nov-2007 : Implemented hashCode() (DG);
  42:  * 
  43:  */
  44: 
  45: package org.jfree.chart.labels;
  46: 
  47: import java.io.Serializable;
  48: import java.text.MessageFormat;
  49: import java.text.NumberFormat;
  50: 
  51: import org.jfree.chart.HashUtilities;
  52: import org.jfree.data.general.DatasetUtilities;
  53: import org.jfree.data.general.PieDataset;
  54: 
  55: /**
  56:  * A base class used for generating pie chart item labels.
  57:  */
  58: public class AbstractPieItemLabelGenerator implements Serializable {
  59:     
  60:     /** For serialization. */
  61:     private static final long serialVersionUID = 7347703325267846275L;
  62:     
  63:     /** The label format string. */
  64:     private String labelFormat;
  65:     
  66:     /** A number formatter for the value. */
  67:     private NumberFormat numberFormat;
  68:     
  69:     /** A number formatter for the percentage. */
  70:     private NumberFormat percentFormat;
  71:     
  72:     /**
  73:      * Creates an item label generator using the specified number formatters.
  74:      *
  75:      * @param labelFormat  the label format string (<code>null</code> not
  76:      *                     permitted).
  77:      * @param numberFormat  the format object for the values (<code>null</code>
  78:      *                      not permitted).
  79:      * @param percentFormat  the format object for the percentages
  80:      *                       (<code>null</code> not permitted).
  81:      */
  82:     protected AbstractPieItemLabelGenerator(String labelFormat,
  83:                                             NumberFormat numberFormat, 
  84:                                             NumberFormat percentFormat) {
  85: 
  86:         if (labelFormat == null) {
  87:             throw new IllegalArgumentException("Null 'labelFormat' argument.");
  88:         }
  89:         if (numberFormat == null) {
  90:             throw new IllegalArgumentException("Null 'numberFormat' argument.");
  91:         }
  92:         if (percentFormat == null) {
  93:             throw new IllegalArgumentException(
  94:                     "Null 'percentFormat' argument.");   
  95:         }
  96:         this.labelFormat = labelFormat;
  97:         this.numberFormat = numberFormat;
  98:         this.percentFormat = percentFormat;
  99: 
 100:     }
 101: 
 102:     /**
 103:      * Returns the label format string.
 104:      * 
 105:      * @return The label format string (never <code>null</code>).
 106:      */
 107:     public String getLabelFormat() {
 108:         return this.labelFormat;
 109:     }
 110:     
 111:     /**
 112:      * Returns the number formatter.
 113:      *
 114:      * @return The formatter (never <code>null</code>).
 115:      */
 116:     public NumberFormat getNumberFormat() {
 117:         return this.numberFormat;
 118:     }
 119: 
 120:     /**
 121:      * Returns the percent formatter.
 122:      *
 123:      * @return The formatter (never <code>null</code>).
 124:      */
 125:     public NumberFormat getPercentFormat() {
 126:         return this.percentFormat;
 127:     }
 128: 
 129:     /**
 130:      * Creates the array of items that can be passed to the 
 131:      * {@link MessageFormat} class for creating labels.  The returned array
 132:      * contains four values:
 133:      * <ul>
 134:      * <li>result[0] = the section key converted to a <code>String</code>;</li>
 135:      * <li>result[1] = the formatted data value;</li>
 136:      * <li>result[2] = the formatted percentage (of the total);</li>
 137:      * <li>result[3] = the formatted total value.</li>
 138:      * </ul>
 139:      *
 140:      * @param dataset  the dataset (<code>null</code> not permitted).
 141:      * @param key  the key (<code>null</code> not permitted).
 142:      *
 143:      * @return The items (never <code>null</code>).
 144:      */
 145:     protected Object[] createItemArray(PieDataset dataset, Comparable key) {
 146:         Object[] result = new Object[4];
 147:         double total = DatasetUtilities.calculatePieDatasetTotal(dataset);
 148:         result[0] = key.toString();
 149:         Number value = dataset.getValue(key);
 150:         if (value != null) {
 151:             result[1] = this.numberFormat.format(value);  
 152:         }
 153:         else {
 154:             result[1] = "null";
 155:         }
 156:         double percent = 0.0;
 157:         if (value != null) {
 158:             double v = value.doubleValue();
 159:             if (v > 0.0) {
 160:                 percent = v / total; 
 161:             }
 162:         }       
 163:         result[2] = this.percentFormat.format(percent);
 164:         result[3] = this.numberFormat.format(total);
 165:         return result;
 166:     }
 167:     
 168:     /**
 169:      * Generates a label for a pie section.
 170:      * 
 171:      * @param dataset  the dataset (<code>null</code> not permitted).
 172:      * @param key  the section key (<code>null</code> not permitted).
 173:      * 
 174:      * @return The label (possibly <code>null</code>).
 175:      */
 176:     protected String generateSectionLabel(PieDataset dataset, Comparable key) {
 177:         String result = null;    
 178:         if (dataset != null) {
 179:             Object[] items = createItemArray(dataset, key);
 180:             result = MessageFormat.format(this.labelFormat, items);
 181:         }
 182:         return result;
 183:     }
 184: 
 185:     /**
 186:      * Tests the generator for equality with an arbitrary object.
 187:      *
 188:      * @param obj  the object to test against (<code>null</code> permitted).
 189:      *
 190:      * @return A boolean.
 191:      */
 192:     public boolean equals(Object obj) {
 193:         if (obj == this) {
 194:             return true;
 195:         }
 196:         if (!(obj instanceof AbstractPieItemLabelGenerator)) {
 197:             return false;
 198:         }
 199:         
 200:         AbstractPieItemLabelGenerator that 
 201:                 = (AbstractPieItemLabelGenerator) obj;
 202:         if (!this.labelFormat.equals(that.labelFormat)) {
 203:             return false;
 204:         }
 205:         if (!this.numberFormat.equals(that.numberFormat)) {
 206:             return false;   
 207:         }
 208:         if (!this.percentFormat.equals(that.percentFormat)) {
 209:             return false;   
 210:         }
 211:         return true;
 212: 
 213:     }
 214:     
 215:     /**
 216:      * Returns a hash code for this instance.
 217:      * 
 218:      * @return A hash code.
 219:      */
 220:     public int hashCode() {
 221:         int result = 127;
 222:         result = HashUtilities.hashCode(result, this.labelFormat);
 223:         result = HashUtilities.hashCode(result, this.numberFormat);
 224:         result = HashUtilities.hashCode(result, this.percentFormat);
 225:         return result;
 226:     }
 227:     
 228:     /**
 229:      * Returns an independent copy of the generator.
 230:      * 
 231:      * @return A clone.
 232:      * 
 233:      * @throws CloneNotSupportedException  should not happen.
 234:      */
 235:     public Object clone() throws CloneNotSupportedException {      
 236:         AbstractPieItemLabelGenerator clone 
 237:                 = (AbstractPieItemLabelGenerator) super.clone();
 238:         if (this.numberFormat != null) {
 239:             clone.numberFormat = (NumberFormat) this.numberFormat.clone();
 240:         }
 241:         if (this.percentFormat != null) {
 242:             clone.percentFormat = (NumberFormat) this.percentFormat.clone();
 243:         }
 244:         return clone;
 245:     }
 246: 
 247: }