Source for org.jfree.chart.util.RelativeDateFormat

   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:  * RelativeDateFormat.java
  29:  * -----------------------
  30:  * (C) Copyright 2006, 2007, by Object Refinery Limited and Contributors.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * Changes:
  36:  * --------
  37:  * 01-Nov-2006 : Version 1 (DG);
  38:  * 23-Nov-2006 : Added argument checks, updated equals(), added clone() and 
  39:  *               hashCode() (DG);
  40:  *
  41:  */
  42: package org.jfree.chart.util;
  43: 
  44: import java.text.DateFormat;
  45: import java.text.DecimalFormat;
  46: import java.text.FieldPosition;
  47: import java.text.NumberFormat;
  48: import java.text.ParsePosition;
  49: import java.util.Calendar;
  50: import java.util.Date;
  51: import java.util.GregorianCalendar;
  52: 
  53: /**
  54:  * A formatter that formats dates to show the elapsed time relative to some
  55:  * base date.
  56:  *
  57:  * @since 1.0.3
  58:  */
  59: public class RelativeDateFormat extends DateFormat {
  60:     
  61:     /** The base milliseconds for the elapsed time calculation. */
  62:     private long baseMillis;
  63:     
  64:     /**
  65:      * A flag that controls whether or not a zero day count is displayed.
  66:      */
  67:     private boolean showZeroDays;
  68:     
  69:     /** 
  70:      * A formatter for the day count (most likely not critical until the
  71:      * day count exceeds 999). 
  72:      */
  73:     private NumberFormat dayFormatter;
  74:     
  75:     /**
  76:      * A string appended after the day count.
  77:      */
  78:     private String daySuffix;
  79:     
  80:     /**
  81:      * A string appended after the hours.
  82:      */
  83:     private String hourSuffix;
  84:     
  85:     /**
  86:      * A string appended after the minutes.
  87:      */
  88:     private String minuteSuffix;
  89:     
  90:     /**
  91:      * A formatter for the seconds (and milliseconds).
  92:      */
  93:     private NumberFormat secondFormatter;
  94:     
  95:     /**
  96:      * A string appended after the seconds.
  97:      */
  98:     private String secondSuffix;
  99: 
 100:     /**
 101:      * A constant for the number of milliseconds in one hour.
 102:      */
 103:     private static long MILLISECONDS_IN_ONE_HOUR = 60 * 60 * 1000L;
 104: 
 105:     /**
 106:      * A constant for the number of milliseconds in one day.
 107:      */
 108:     private static long MILLISECONDS_IN_ONE_DAY = 24 * MILLISECONDS_IN_ONE_HOUR;
 109:     
 110:     /**
 111:      * Creates a new instance.
 112:      */
 113:     public RelativeDateFormat() {
 114:         this(0L);  
 115:     }
 116:     
 117:     /**
 118:      * Creates a new instance.
 119:      * 
 120:      * @param time  the date/time (<code>null</code> not permitted).
 121:      */
 122:     public RelativeDateFormat(Date time) {
 123:         this(time.getTime());
 124:     }
 125:     
 126:     /**
 127:      * Creates a new instance.
 128:      * 
 129:      * @param baseMillis  the time zone (<code>null</code> not permitted).
 130:      */
 131:     public RelativeDateFormat(long baseMillis) {
 132:         super();        
 133:         this.baseMillis = baseMillis;
 134:         this.showZeroDays = false;
 135:         this.dayFormatter = NumberFormat.getInstance();
 136:         this.daySuffix = "d";
 137:         this.hourSuffix = "h";
 138:         this.minuteSuffix = "m";
 139:         this.secondFormatter = NumberFormat.getNumberInstance();
 140:         this.secondFormatter.setMaximumFractionDigits(3);
 141:         this.secondFormatter.setMinimumFractionDigits(3);
 142:         this.secondSuffix = "s";
 143: 
 144:         // we don't use the calendar or numberFormat fields, but equals(Object) 
 145:         // is failing without them being non-null
 146:         this.calendar = new GregorianCalendar();
 147:         this.numberFormat = new DecimalFormat("0");    
 148:     }
 149:     
 150:     /**
 151:      * Returns the base date/time used to calculate the elapsed time for 
 152:      * display.
 153:      * 
 154:      * @return The base date/time in milliseconds since 1-Jan-1970.
 155:      * 
 156:      * @see #setBaseMillis(long)
 157:      */
 158:     public long getBaseMillis() {
 159:         return this.baseMillis;
 160:     }
 161:     
 162:     /**
 163:      * Sets the base date/time used to calculate the elapsed time for display.  
 164:      * This should be specified in milliseconds using the same encoding as
 165:      * <code>java.util.Date</code>.
 166:      * 
 167:      * @param baseMillis  the base date/time in milliseconds.
 168:      * 
 169:      * @see #getBaseMillis()
 170:      */
 171:     public void setBaseMillis(long baseMillis) {
 172:         this.baseMillis = baseMillis;
 173:     }
 174:     
 175:     /**
 176:      * Returns the flag that controls whether or not zero day counts are 
 177:      * shown in the formatted output.
 178:      * 
 179:      * @return The flag.
 180:      * 
 181:      * @see #setShowZeroDays(boolean)
 182:      */
 183:     public boolean getShowZeroDays() {
 184:         return this.showZeroDays;
 185:     }
 186:     
 187:     /**
 188:      * Sets the flag that controls whether or not zero day counts are shown
 189:      * in the formatted output.
 190:      * 
 191:      * @param show  the flag.
 192:      * 
 193:      * @see #getShowZeroDays()
 194:      */
 195:     public void setShowZeroDays(boolean show) {
 196:         this.showZeroDays = show;
 197:     }
 198:     
 199:     /**
 200:      * Returns the string that is appended to the day count.
 201:      * 
 202:      * @return The string.
 203:      * 
 204:      * @see #setDaySuffix(String)
 205:      */
 206:     public String getDaySuffix() {
 207:         return this.daySuffix;
 208:     }
 209:     
 210:     /**
 211:      * Sets the string that is appended to the day count.
 212:      * 
 213:      * @param suffix  the suffix (<code>null</code> not permitted).
 214:      * 
 215:      * @see #getDaySuffix()
 216:      */
 217:     public void setDaySuffix(String suffix) {
 218:         if (suffix == null) {
 219:             throw new IllegalArgumentException("Null 'suffix' argument.");
 220:         }
 221:         this.daySuffix = suffix;
 222:     }
 223: 
 224:     /**
 225:      * Returns the string that is appended to the hour count.
 226:      * 
 227:      * @return The string.
 228:      * 
 229:      * @see #setHourSuffix(String)
 230:      */
 231:     public String getHourSuffix() {
 232:         return this.hourSuffix;
 233:     }
 234:     
 235:     /**
 236:      * Sets the string that is appended to the hour count.
 237:      * 
 238:      * @param suffix  the suffix (<code>null</code> not permitted).
 239:      * 
 240:      * @see #getHourSuffix()
 241:      */
 242:     public void setHourSuffix(String suffix) {
 243:         if (suffix == null) {
 244:             throw new IllegalArgumentException("Null 'suffix' argument.");
 245:         }
 246:         this.hourSuffix = suffix;
 247:     }
 248: 
 249:     /**
 250:      * Returns the string that is appended to the minute count.
 251:      * 
 252:      * @return The string.
 253:      * 
 254:      * @see #setMinuteSuffix(String)
 255:      */
 256:     public String getMinuteSuffix() {
 257:         return this.minuteSuffix;
 258:     }
 259:     
 260:     /**
 261:      * Sets the string that is appended to the minute count.
 262:      * 
 263:      * @param suffix  the suffix (<code>null</code> not permitted).
 264:      * 
 265:      * @see #getMinuteSuffix()
 266:      */
 267:     public void setMinuteSuffix(String suffix) {
 268:         if (suffix == null) {
 269:             throw new IllegalArgumentException("Null 'suffix' argument.");
 270:         }
 271:         this.minuteSuffix = suffix;
 272:     }
 273: 
 274:     /**
 275:      * Returns the string that is appended to the second count.
 276:      * 
 277:      * @return The string.
 278:      * 
 279:      * @see #setSecondSuffix(String)
 280:      */
 281:     public String getSecondSuffix() {
 282:         return this.secondSuffix;
 283:     }
 284:     
 285:     /**
 286:      * Sets the string that is appended to the second count.
 287:      * 
 288:      * @param suffix  the suffix (<code>null</code> not permitted).
 289:      * 
 290:      * @see #getSecondSuffix()
 291:      */
 292:     public void setSecondSuffix(String suffix) {
 293:         if (suffix == null) {
 294:             throw new IllegalArgumentException("Null 'suffix' argument.");
 295:         }
 296:         this.secondSuffix = suffix;
 297:     }
 298:     
 299:     /**
 300:      * Sets the formatter for the seconds and milliseconds.
 301:      * 
 302:      * @param formatter  the formatter (<code>null</code> not permitted).
 303:      */
 304:     public void setSecondFormatter(NumberFormat formatter) {
 305:         if (formatter == null) {
 306:             throw new IllegalArgumentException("Null 'formatter' argument.");
 307:         }
 308:         this.secondFormatter = formatter;
 309:     }
 310: 
 311:     /**
 312:      * Formats the given date as the amount of elapsed time (relative to the
 313:      * base date specified in the constructor).
 314:      * 
 315:      * @param date  the date.
 316:      * @param toAppendTo  the string buffer.
 317:      * @param fieldPosition  the field position.
 318:      * 
 319:      * @return The formatted date.
 320:      */
 321:     public StringBuffer format(Date date, StringBuffer toAppendTo,
 322:                                FieldPosition fieldPosition) {
 323:         long currentMillis = date.getTime();
 324:         long elapsed = currentMillis - this.baseMillis;
 325:         
 326:         long days = elapsed / MILLISECONDS_IN_ONE_DAY;
 327:         elapsed = elapsed - (days * MILLISECONDS_IN_ONE_DAY);
 328:         long hours = elapsed / MILLISECONDS_IN_ONE_HOUR;
 329:         elapsed = elapsed - (hours * MILLISECONDS_IN_ONE_HOUR);
 330:         long minutes = elapsed / 60000L;
 331:         elapsed = elapsed - (minutes * 60000L);
 332:         double seconds = elapsed / 1000.0;
 333:         if (days != 0 || this.showZeroDays) {
 334:             toAppendTo.append(this.dayFormatter.format(days) + getDaySuffix());
 335:         }
 336:         toAppendTo.append(String.valueOf(hours) + getHourSuffix());
 337:         toAppendTo.append(String.valueOf(minutes) + getMinuteSuffix());
 338:         toAppendTo.append(this.secondFormatter.format(seconds) 
 339:                 + getSecondSuffix());
 340:         return toAppendTo;   
 341:     }
 342: 
 343:     /**
 344:      * Parses the given string (not implemented).
 345:      * 
 346:      * @param source  the date string.
 347:      * @param pos  the parse position.
 348:      * 
 349:      * @return <code>null</code>, as this method has not been implemented.
 350:      */
 351:     public Date parse(String source, ParsePosition pos) {
 352:         return null;   
 353:     }
 354: 
 355:     /**
 356:      * Tests this formatter for equality with an arbitrary object.
 357:      * 
 358:      * @param obj  the object (<code>null</code> permitted).
 359:      * 
 360:      * @return A boolean.
 361:      */
 362:     public boolean equals(Object obj) {
 363:         if (obj == this) {
 364:             return true;
 365:         }
 366:         if (!(obj instanceof RelativeDateFormat)) {
 367:             return false;
 368:         }
 369:         if (!super.equals(obj)) {
 370:             return false;
 371:         }
 372:         RelativeDateFormat that = (RelativeDateFormat) obj;
 373:         if (this.baseMillis != that.baseMillis) {
 374:             return false;
 375:         }
 376:         if (this.showZeroDays != that.showZeroDays) {
 377:             return false;
 378:         }
 379:         if (!this.daySuffix.equals(that.daySuffix)) {
 380:             return false;
 381:         }
 382:         if (!this.hourSuffix.equals(that.hourSuffix)) {
 383:             return false;
 384:         }
 385:         if (!this.minuteSuffix.equals(that.minuteSuffix)) {
 386:             return false;
 387:         }
 388:         if (!this.secondSuffix.equals(that.secondSuffix)) {
 389:             return false;
 390:         }
 391:         if (!this.secondFormatter.equals(that.secondFormatter)) {
 392:             return false;
 393:         }
 394:         return true;
 395:     }
 396:     
 397:     /**
 398:      * Returns a hash code for this instance.
 399:      * 
 400:      * @return A hash code.
 401:      */
 402:     public int hashCode() {
 403:         int result = 193;
 404:         result = 37 * result 
 405:                 + (int) (this.baseMillis ^ (this.baseMillis >>> 32));
 406:         result = 37 * result + this.daySuffix.hashCode();
 407:         result = 37 * result + this.hourSuffix.hashCode();
 408:         result = 37 * result + this.minuteSuffix.hashCode();
 409:         result = 37 * result + this.secondSuffix.hashCode();
 410:         result = 37 * result + this.secondFormatter.hashCode();
 411:         return result;
 412:     }
 413: 
 414:     /**
 415:      * Returns a clone of this instance.
 416:      * 
 417:      * @return A clone.
 418:      */
 419:     public Object clone() {
 420:         RelativeDateFormat clone = (RelativeDateFormat) super.clone();
 421:         clone.dayFormatter = (NumberFormat) this.dayFormatter.clone();
 422:         clone.secondFormatter = (NumberFormat) this.secondFormatter.clone();
 423:         return clone;
 424:     }
 425:     
 426:     /**
 427:      * Some test code.
 428:      * 
 429:      * @param args  ignored.
 430:      */
 431:     public static void main(String[] args) {
 432:         GregorianCalendar c0 = new GregorianCalendar(2006, 10, 1, 0, 0, 0);
 433:         GregorianCalendar c1 = new GregorianCalendar(2006, 10, 1, 11, 37, 43);
 434:         c1.set(Calendar.MILLISECOND, 123);
 435:         
 436:         System.out.println("Default: ");
 437:         RelativeDateFormat rdf = new RelativeDateFormat(c0.getTimeInMillis());
 438:         System.out.println(rdf.format(c1.getTime()));
 439:         System.out.println();
 440:         
 441:         System.out.println("Hide milliseconds: ");
 442:         rdf.setSecondFormatter(new DecimalFormat("0"));
 443:         System.out.println(rdf.format(c1.getTime()));        
 444:         System.out.println();
 445: 
 446:         System.out.println("Show zero day output: ");
 447:         rdf.setShowZeroDays(true);
 448:         System.out.println(rdf.format(c1.getTime()));
 449:         System.out.println();
 450:         
 451:         System.out.println("Alternative suffixes: ");
 452:         rdf.setShowZeroDays(false);
 453:         rdf.setDaySuffix(":");
 454:         rdf.setHourSuffix(":");
 455:         rdf.setMinuteSuffix(":");
 456:         rdf.setSecondSuffix("");
 457:         System.out.println(rdf.format(c1.getTime()));
 458:         System.out.println();
 459:     }
 460: }