Source for org.jfree.chart.labels.AbstractXYItemLabelGenerator

   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:  * AbstractXYItemLabelGenerator.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:  * 27-Feb-2004 : Version 1 (DG);
  38:  * 12-May-2004 : Moved default tool tip format to 
  39:  *               StandardXYToolTipGenerator (DG);
  40:  * 15-Jul-2004 : Switched getX() with getXValue() and getY() with 
  41:  *               getYValue() (DG);
  42:  * 08-Oct-2004 : Modified createItemArray() method to handle null values (DG);
  43:  * 10-Jan-2005 : Updated createItemArray() to use x, y primitives if 
  44:  *               possible (DG);
  45:  * ------------- JFREECHART 1.0.x --------------------------------------------
  46:  * 26-Jan-2006 : Minor API doc update (DG);
  47:  * 25-Jan-2007 : Added new constructor and fixed bug in clone() method (DG);
  48:  * 16-Oct-2007 : Removed redundant code (DG);
  49:  * 23-Nov-2007 : Implemented hashCode() (DG);
  50:  * 
  51:  */
  52: 
  53: package org.jfree.chart.labels;
  54: 
  55: import java.io.Serializable;
  56: import java.text.DateFormat;
  57: import java.text.MessageFormat;
  58: import java.text.NumberFormat;
  59: import java.util.Date;
  60: 
  61: import org.jfree.chart.HashUtilities;
  62: import org.jfree.data.xy.XYDataset;
  63: import org.jfree.util.ObjectUtilities;
  64: 
  65: /**
  66:  * A base class for creating item label generators.
  67:  */
  68: public class AbstractXYItemLabelGenerator implements Cloneable, Serializable {
  69:     
  70:     /** For serialization. */
  71:     private static final long serialVersionUID = 5869744396278660636L;
  72:     
  73:     /** The item label format string. */
  74:     private String formatString;
  75:     
  76:     /** A number formatter for the x value. */
  77:     private NumberFormat xFormat;
  78:     
  79:     /** A date formatter for the x value. */
  80:     private DateFormat xDateFormat;
  81: 
  82:     /** A formatter for the y value. */
  83:     private NumberFormat yFormat;
  84: 
  85:     /** A date formatter for the y value. */
  86:     private DateFormat yDateFormat;
  87:     
  88:     /** The string used to represent 'null' for the y-value. */
  89:     private String nullYString = "null";
  90:     
  91:     /**
  92:      * Creates an item label generator using default number formatters.
  93:      */
  94:     protected AbstractXYItemLabelGenerator() {
  95:         this("{2}", NumberFormat.getNumberInstance(), 
  96:                 NumberFormat.getNumberInstance());
  97:     }
  98: 
  99:     /**
 100:      * Creates an item label generator using the specified number formatters.
 101:      *
 102:      * @param formatString  the item label format string (<code>null</code> 
 103:      *                      not permitted).
 104:      * @param xFormat  the format object for the x values (<code>null</code> 
 105:      *                 not permitted).
 106:      * @param yFormat  the format object for the y values (<code>null</code> 
 107:      *                 not permitted).
 108:      */
 109:     protected AbstractXYItemLabelGenerator(String formatString,
 110:                                            NumberFormat xFormat, 
 111:                                            NumberFormat yFormat) {
 112: 
 113:         if (formatString == null) {
 114:             throw new IllegalArgumentException("Null 'formatString' argument.");
 115:         }
 116:         if (xFormat == null) {
 117:             throw new IllegalArgumentException("Null 'xFormat' argument.");   
 118:         }
 119:         if (yFormat == null) {
 120:             throw new IllegalArgumentException("Null 'yFormat' argument.");   
 121:         }
 122:         this.formatString = formatString;
 123:         this.xFormat = xFormat;
 124:         this.yFormat = yFormat;
 125: 
 126:     }
 127: 
 128:     /**
 129:      * Creates an item label generator using the specified number formatters.
 130:      *
 131:      * @param formatString  the item label format string (<code>null</code> 
 132:      *                      not permitted).
 133:      * @param xFormat  the format object for the x values (<code>null</code> 
 134:      *                 permitted).
 135:      * @param yFormat  the format object for the y values (<code>null</code> 
 136:      *                 not permitted).
 137:      */
 138:     protected AbstractXYItemLabelGenerator(String formatString,
 139:                                            DateFormat xFormat, 
 140:                                            NumberFormat yFormat) {
 141: 
 142:         this(formatString, NumberFormat.getInstance(), yFormat);
 143:         this.xDateFormat = xFormat;
 144:     
 145:     }
 146:     
 147:     /**
 148:      * Creates an item label generator using the specified formatters (a 
 149:      * number formatter for the x-values and a date formatter for the 
 150:      * y-values).
 151:      *
 152:      * @param formatString  the item label format string (<code>null</code> 
 153:      *                      not permitted).
 154:      * @param xFormat  the format object for the x values (<code>null</code> 
 155:      *                 permitted).
 156:      * @param yFormat  the format object for the y values (<code>null</code> 
 157:      *                 not permitted).
 158:      *                 
 159:      * @since 1.0.4
 160:      */
 161:     protected AbstractXYItemLabelGenerator(String formatString,
 162:             NumberFormat xFormat, DateFormat yFormat) {
 163:         
 164:         this(formatString, xFormat, NumberFormat.getInstance());
 165:         this.yDateFormat = yFormat;
 166:     }
 167:     
 168:     /**
 169:      * Creates an item label generator using the specified number formatters.
 170:      *
 171:      * @param formatString  the item label format string (<code>null</code> 
 172:      *                      not permitted).
 173:      * @param xFormat  the format object for the x values (<code>null</code> 
 174:      *                 permitted).
 175:      * @param yFormat  the format object for the y values (<code>null</code> 
 176:      *                 not permitted).
 177:      */
 178:     protected AbstractXYItemLabelGenerator(String formatString,
 179:                                            DateFormat xFormat, 
 180:                                            DateFormat yFormat) {
 181: 
 182:         this(formatString, NumberFormat.getInstance(), 
 183:                 NumberFormat.getInstance());
 184:         this.xDateFormat = xFormat;
 185:         this.yDateFormat = yFormat;
 186:     
 187:     }
 188:     
 189:     /**
 190:      * Returns the format string (this controls the overall structure of the 
 191:      * label).
 192:      * 
 193:      * @return The format string (never <code>null</code>).
 194:      */
 195:     public String getFormatString() {
 196:         return this.formatString;
 197:     }
 198:     
 199:     /**
 200:      * Returns the number formatter for the x-values.
 201:      *
 202:      * @return The number formatter (possibly <code>null</code>).
 203:      */
 204:     public NumberFormat getXFormat() {
 205:         return this.xFormat;
 206:     }
 207: 
 208:     /**
 209:      * Returns the date formatter for the x-values.
 210:      *
 211:      * @return The date formatter (possibly <code>null</code>).
 212:      */
 213:     public DateFormat getXDateFormat() {
 214:         return this.xDateFormat;
 215:     }
 216: 
 217:     /**
 218:      * Returns the number formatter for the y-values.
 219:      *
 220:      * @return The number formatter (possibly <code>null</code>).
 221:      */
 222:     public NumberFormat getYFormat() {
 223:         return this.yFormat;
 224:     }
 225: 
 226:     /**
 227:      * Returns the date formatter for the y-values.
 228:      *
 229:      * @return The date formatter (possibly <code>null</code>).
 230:      */
 231:     public DateFormat getYDateFormat() {
 232:         return this.yDateFormat;
 233:     }
 234: 
 235:     /**
 236:      * Generates a label string for an item in the dataset.
 237:      *
 238:      * @param dataset  the dataset (<code>null</code> not permitted).
 239:      * @param series  the series (zero-based index).
 240:      * @param item  the item (zero-based index).
 241:      *
 242:      * @return The label (possibly <code>null</code>).
 243:      */
 244:     public String generateLabelString(XYDataset dataset, int series, int item) {
 245:         String result = null;    
 246:         Object[] items = createItemArray(dataset, series, item);
 247:         result = MessageFormat.format(this.formatString, items);
 248:         return result;
 249:     }
 250: 
 251:     /**
 252:      * Creates the array of items that can be passed to the 
 253:      * {@link MessageFormat} class for creating labels.
 254:      *
 255:      * @param dataset  the dataset (<code>null</code> not permitted).
 256:      * @param series  the series (zero-based index).
 257:      * @param item  the item (zero-based index).
 258:      *
 259:      * @return An array of three items from the dataset formatted as
 260:      *         <code>String</code> objects (never <code>null</code>).
 261:      */
 262:     protected Object[] createItemArray(XYDataset dataset, int series, 
 263:                                        int item) {
 264:         Object[] result = new Object[3];
 265:         result[0] = dataset.getSeriesKey(series).toString();
 266:         
 267:         double x = dataset.getXValue(series, item);
 268:         if (this.xDateFormat != null) {
 269:             result[1] = this.xDateFormat.format(new Date((long) x));   
 270:         }
 271:         else {
 272:             result[1] = this.xFormat.format(x);
 273:         }
 274:         
 275:         double y = dataset.getYValue(series, item);
 276:         if (Double.isNaN(y) && dataset.getY(series, item) == null) {
 277:             result[2] = this.nullYString;
 278:         }
 279:         else {
 280:             if (this.yDateFormat != null) {
 281:                 result[2] = this.yDateFormat.format(new Date((long) y));   
 282:             }
 283:             else {
 284:                 result[2] = this.yFormat.format(y);
 285:             }
 286:         }
 287:         return result;
 288:     }
 289: 
 290:     /**
 291:      * Tests this object for equality with an arbitrary object.
 292:      *
 293:      * @param obj  the other object (<code>null</code> permitted).
 294:      *
 295:      * @return A boolean.
 296:      */
 297:     public boolean equals(Object obj) {
 298:         if (obj == this) {
 299:             return true;
 300:         }
 301:         if (!(obj instanceof AbstractXYItemLabelGenerator)) {
 302:             return false;
 303:         }
 304:         AbstractXYItemLabelGenerator that = (AbstractXYItemLabelGenerator) obj;
 305:         if (!this.formatString.equals(that.formatString)) {
 306:             return false;   
 307:         }
 308:         if (!ObjectUtilities.equal(this.xFormat, that.xFormat)) {
 309:             return false;   
 310:         }
 311:         if (!ObjectUtilities.equal(this.xDateFormat, that.xDateFormat)) {
 312:             return false;   
 313:         }
 314:         if (!ObjectUtilities.equal(this.yFormat, that.yFormat)) {
 315:             return false;   
 316:         }
 317:         if (!ObjectUtilities.equal(this.yDateFormat, that.yDateFormat)) {
 318:             return false;   
 319:         }
 320:         return true;
 321:     }
 322: 
 323:     /**
 324:      * Returns a hash code for this instance.
 325:      * 
 326:      * @return A hash code.
 327:      */
 328:     public int hashCode() {
 329:         int result = 127;
 330:         result = HashUtilities.hashCode(result, this.formatString);
 331:         result = HashUtilities.hashCode(result, this.xFormat);
 332:         result = HashUtilities.hashCode(result, this.xDateFormat);
 333:         result = HashUtilities.hashCode(result, this.yFormat);
 334:         result = HashUtilities.hashCode(result, this.yDateFormat);
 335:         return result;
 336:     }
 337:     
 338:     /**
 339:      * Returns an independent copy of the generator.
 340:      * 
 341:      * @return A clone.
 342:      * 
 343:      * @throws CloneNotSupportedException if cloning is not supported.
 344:      */
 345:     public Object clone() throws CloneNotSupportedException {
 346:         AbstractXYItemLabelGenerator clone 
 347:                 = (AbstractXYItemLabelGenerator) super.clone();
 348:         if (this.xFormat != null) {
 349:             clone.xFormat = (NumberFormat) this.xFormat.clone();
 350:         }
 351:         if (this.yFormat != null) {
 352:             clone.yFormat = (NumberFormat) this.yFormat.clone();
 353:         }
 354:         if (this.xDateFormat != null) {
 355:             clone.xDateFormat = (DateFormat) this.xDateFormat.clone();
 356:         }
 357:         if (this.yDateFormat != null) {
 358:             clone.yDateFormat = (DateFormat) this.yDateFormat.clone();
 359:         }        
 360:         return clone;
 361:     }
 362:     
 363: }