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 * Week.java
029 * ---------
030 * (C) Copyright 2001-2007, by Object Refinery Limited and Contributors.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): Aimin Han;
034 *
035 * Changes
036 * -------
037 * 11-Oct-2001 : Version 1 (DG);
038 * 18-Dec-2001 : Changed order of parameters in constructor (DG);
039 * 19-Dec-2001 : Added a new constructor as suggested by Paul English (DG);
040 * 29-Jan-2002 : Worked on the parseWeek() method (DG);
041 * 13-Feb-2002 : Fixed bug in Week(Date) constructor (DG);
042 * 26-Feb-2002 : Changed getStart(), getMiddle() and getEnd() methods to
043 * evaluate with reference to a particular time zone (DG);
044 * 05-Apr-2002 : Reinstated this class to the JCommon library (DG);
045 * 24-Jun-2002 : Removed unnecessary main method (DG);
046 * 10-Sep-2002 : Added getSerialIndex() method (DG);
047 * 06-Oct-2002 : Fixed errors reported by Checkstyle (DG);
048 * 18-Oct-2002 : Changed to observe 52 or 53 weeks per year, consistent with
049 * GregorianCalendar. Thanks to Aimin Han for the code (DG);
050 * 02-Jan-2003 : Removed debug code (DG);
051 * 13-Mar-2003 : Moved to com.jrefinery.data.time package, and implemented
052 * Serializable (DG);
053 * 21-Oct-2003 : Added hashCode() method (DG);
054 * 24-May-2004 : Modified getFirstMillisecond() and getLastMillisecond() to
055 * take account of firstDayOfWeek setting in Java's Calendar
056 * class (DG);
057 * 30-Sep-2004 : Replaced getTime().getTime() with getTimeInMillis() (DG);
058 * 04-Nov-2004 : Reverted change of 30-Sep-2004, because it won't work for
059 * JDK 1.3 (DG);
060 * ------------- JFREECHART 1.0.x ---------------------------------------------
061 * 06-Mar-2006 : Fix for bug 1448828, incorrect calculation of week and year
062 * for the first few days of some years (DG);
063 * 05-Oct-2006 : Updated API docs (DG);
064 * 06-Oct-2006 : Refactored to cache first and last millisecond values (DG);
065 * 09-Jan-2007 : Fixed bug in next() (DG);
066 * 28-Aug-2007 : Added new constructor to avoid problem in creating new
067 * instances (DG);
068 * 19-Dec-2007 : Fixed bug in deprecated constructor (DG);
069 *
070 */
071
072 package org.jfree.data.time;
073
074 import java.io.Serializable;
075 import java.util.Calendar;
076 import java.util.Date;
077 import java.util.Locale;
078 import java.util.TimeZone;
079
080 /**
081 * A calendar week. All years are considered to have 53 weeks, numbered from 1
082 * to 53, although in many cases the 53rd week is empty. Most of the time, the
083 * 1st week of the year *begins* in the previous calendar year, but it always
084 * finishes in the current year (this behaviour matches the workings of the
085 * <code>GregorianCalendar</code> class).
086 * <P>
087 * This class is immutable, which is a requirement for all
088 * {@link RegularTimePeriod} subclasses.
089 */
090 public class Week extends RegularTimePeriod implements Serializable {
091
092 /** For serialization. */
093 private static final long serialVersionUID = 1856387786939865061L;
094
095 /** Constant for the first week in the year. */
096 public static final int FIRST_WEEK_IN_YEAR = 1;
097
098 /** Constant for the last week in the year. */
099 public static final int LAST_WEEK_IN_YEAR = 53;
100
101 /** The year in which the week falls. */
102 private short year;
103
104 /** The week (1-53). */
105 private byte week;
106
107 /** The first millisecond. */
108 private long firstMillisecond;
109
110 /** The last millisecond. */
111 private long lastMillisecond;
112
113 /**
114 * Creates a new time period for the week in which the current system
115 * date/time falls.
116 */
117 public Week() {
118 this(new Date());
119 }
120
121 /**
122 * Creates a time period representing the week in the specified year.
123 *
124 * @param week the week (1 to 53).
125 * @param year the year (1900 to 9999).
126 */
127 public Week(int week, int year) {
128 if ((week < FIRST_WEEK_IN_YEAR) && (week > LAST_WEEK_IN_YEAR)) {
129 throw new IllegalArgumentException(
130 "The 'week' argument must be in the range 1 - 53.");
131 }
132 this.week = (byte) week;
133 this.year = (short) year;
134 peg(Calendar.getInstance());
135 }
136
137 /**
138 * Creates a time period representing the week in the specified year.
139 *
140 * @param week the week (1 to 53).
141 * @param year the year (1900 to 9999).
142 */
143 public Week(int week, Year year) {
144 if ((week < FIRST_WEEK_IN_YEAR) && (week > LAST_WEEK_IN_YEAR)) {
145 throw new IllegalArgumentException(
146 "The 'week' argument must be in the range 1 - 53.");
147 }
148 this.week = (byte) week;
149 this.year = (short) year.getYear();
150 peg(Calendar.getInstance());
151 }
152
153 /**
154 * Creates a time period for the week in which the specified date/time
155 * falls.
156 *
157 * @param time the time (<code>null</code> not permitted).
158 */
159 public Week(Date time) {
160 // defer argument checking...
161 this(time, RegularTimePeriod.DEFAULT_TIME_ZONE, Locale.getDefault());
162 }
163
164 /**
165 * Creates a time period for the week in which the specified date/time
166 * falls, calculated relative to the specified time zone.
167 *
168 * @param time the date/time (<code>null</code> not permitted).
169 * @param zone the time zone (<code>null</code> not permitted).
170 *
171 * @deprecated As of 1.0.7, use {@link #Week(Date, TimeZone, Locale)}.
172 */
173 public Week(Date time, TimeZone zone) {
174 // defer argument checking...
175 this(time, zone, Locale.getDefault());
176 }
177
178 /**
179 * Creates a time period for the week in which the specified date/time
180 * falls, calculated relative to the specified time zone.
181 *
182 * @param time the date/time (<code>null</code> not permitted).
183 * @param zone the time zone (<code>null</code> not permitted).
184 * @param locale the locale (<code>null</code> not permitted).
185 *
186 * @since 1.0.7
187 */
188 public Week(Date time, TimeZone zone, Locale locale) {
189 if (time == null) {
190 throw new IllegalArgumentException("Null 'time' argument.");
191 }
192 if (zone == null) {
193 throw new IllegalArgumentException("Null 'zone' argument.");
194 }
195 if (locale == null) {
196 throw new IllegalArgumentException("Null 'locale' argument.");
197 }
198 Calendar calendar = Calendar.getInstance(zone, locale);
199 calendar.setTime(time);
200
201 // sometimes the last few days of the year are considered to fall in
202 // the *first* week of the following year. Refer to the Javadocs for
203 // GregorianCalendar.
204 int tempWeek = calendar.get(Calendar.WEEK_OF_YEAR);
205 if (tempWeek == 1
206 && calendar.get(Calendar.MONTH) == Calendar.DECEMBER) {
207 this.week = 1;
208 this.year = (short) (calendar.get(Calendar.YEAR) + 1);
209 }
210 else {
211 this.week = (byte) Math.min(tempWeek, LAST_WEEK_IN_YEAR);
212 int yyyy = calendar.get(Calendar.YEAR);
213 // alternatively, sometimes the first few days of the year are
214 // considered to fall in the *last* week of the previous year...
215 if (calendar.get(Calendar.MONTH) == Calendar.JANUARY
216 && this.week >= 52) {
217 yyyy--;
218 }
219 this.year = (short) yyyy;
220 }
221 peg(calendar);
222 }
223
224 /**
225 * Returns the year in which the week falls.
226 *
227 * @return The year (never <code>null</code>).
228 */
229 public Year getYear() {
230 return new Year(this.year);
231 }
232
233 /**
234 * Returns the year in which the week falls, as an integer value.
235 *
236 * @return The year.
237 */
238 public int getYearValue() {
239 return this.year;
240 }
241
242 /**
243 * Returns the week.
244 *
245 * @return The week.
246 */
247 public int getWeek() {
248 return this.week;
249 }
250
251 /**
252 * Returns the first millisecond of the week. This will be determined
253 * relative to the time zone specified in the constructor, or in the
254 * calendar instance passed in the most recent call to the
255 * {@link #peg(Calendar)} method.
256 *
257 * @return The first millisecond of the week.
258 *
259 * @see #getLastMillisecond()
260 */
261 public long getFirstMillisecond() {
262 return this.firstMillisecond;
263 }
264
265 /**
266 * Returns the last millisecond of the week. This will be
267 * determined relative to the time zone specified in the constructor, or
268 * in the calendar instance passed in the most recent call to the
269 * {@link #peg(Calendar)} method.
270 *
271 * @return The last millisecond of the week.
272 *
273 * @see #getFirstMillisecond()
274 */
275 public long getLastMillisecond() {
276 return this.lastMillisecond;
277 }
278
279 /**
280 * Recalculates the start date/time and end date/time for this time period
281 * relative to the supplied calendar (which incorporates a time zone).
282 *
283 * @param calendar the calendar (<code>null</code> not permitted).
284 *
285 * @since 1.0.3
286 */
287 public void peg(Calendar calendar) {
288 this.firstMillisecond = getFirstMillisecond(calendar);
289 this.lastMillisecond = getLastMillisecond(calendar);
290 }
291
292 /**
293 * Returns the week preceding this one. This method will return
294 * <code>null</code> for some lower limit on the range of weeks (currently
295 * week 1, 1900). For week 1 of any year, the previous week is always week
296 * 53, but week 53 may not contain any days (you should check for this).
297 *
298 * @return The preceding week (possibly <code>null</code>).
299 */
300 public RegularTimePeriod previous() {
301
302 Week result;
303 if (this.week != FIRST_WEEK_IN_YEAR) {
304 result = new Week(this.week - 1, this.year);
305 }
306 else {
307 // we need to work out if the previous year has 52 or 53 weeks...
308 if (this.year > 1900) {
309 int yy = this.year - 1;
310 Calendar prevYearCalendar = Calendar.getInstance();
311 prevYearCalendar.set(yy, Calendar.DECEMBER, 31);
312 result = new Week(prevYearCalendar.getActualMaximum(
313 Calendar.WEEK_OF_YEAR), yy);
314 }
315 else {
316 result = null;
317 }
318 }
319 return result;
320
321 }
322
323 /**
324 * Returns the week following this one. This method will return
325 * <code>null</code> for some upper limit on the range of weeks (currently
326 * week 53, 9999). For week 52 of any year, the following week is always
327 * week 53, but week 53 may not contain any days (you should check for
328 * this).
329 *
330 * @return The following week (possibly <code>null</code>).
331 */
332 public RegularTimePeriod next() {
333
334 Week result;
335 if (this.week < 52) {
336 result = new Week(this.week + 1, this.year);
337 }
338 else {
339 Calendar calendar = Calendar.getInstance();
340 calendar.set(this.year, Calendar.DECEMBER, 31);
341 int actualMaxWeek
342 = calendar.getActualMaximum(Calendar.WEEK_OF_YEAR);
343 if (this.week < actualMaxWeek) {
344 result = new Week(this.week + 1, this.year);
345 }
346 else {
347 if (this.year < 9999) {
348 result = new Week(FIRST_WEEK_IN_YEAR, this.year + 1);
349 }
350 else {
351 result = null;
352 }
353 }
354 }
355 return result;
356
357 }
358
359 /**
360 * Returns a serial index number for the week.
361 *
362 * @return The serial index number.
363 */
364 public long getSerialIndex() {
365 return this.year * 53L + this.week;
366 }
367
368 /**
369 * Returns the first millisecond of the week, evaluated using the supplied
370 * calendar (which determines the time zone).
371 *
372 * @param calendar the calendar (<code>null</code> not permitted).
373 *
374 * @return The first millisecond of the week.
375 *
376 * @throws NullPointerException if <code>calendar</code> is
377 * <code>null</code>.
378 */
379 public long getFirstMillisecond(Calendar calendar) {
380 Calendar c = (Calendar) calendar.clone();
381 c.clear();
382 c.set(Calendar.YEAR, this.year);
383 c.set(Calendar.WEEK_OF_YEAR, this.week);
384 c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
385 c.set(Calendar.HOUR, 0);
386 c.set(Calendar.MINUTE, 0);
387 c.set(Calendar.SECOND, 0);
388 c.set(Calendar.MILLISECOND, 0);
389 //return c.getTimeInMillis(); // this won't work for JDK 1.3
390 return c.getTime().getTime();
391 }
392
393 /**
394 * Returns the last millisecond of the week, evaluated using the supplied
395 * calendar (which determines the time zone).
396 *
397 * @param calendar the calendar (<code>null</code> not permitted).
398 *
399 * @return The last millisecond of the week.
400 *
401 * @throws NullPointerException if <code>calendar</code> is
402 * <code>null</code>.
403 */
404 public long getLastMillisecond(Calendar calendar) {
405 Calendar c = (Calendar) calendar.clone();
406 c.clear();
407 c.set(Calendar.YEAR, this.year);
408 c.set(Calendar.WEEK_OF_YEAR, this.week + 1);
409 c.set(Calendar.DAY_OF_WEEK, c.getFirstDayOfWeek());
410 c.set(Calendar.HOUR, 0);
411 c.set(Calendar.MINUTE, 0);
412 c.set(Calendar.SECOND, 0);
413 c.set(Calendar.MILLISECOND, 0);
414 //return c.getTimeInMillis(); // this won't work for JDK 1.3
415 return c.getTime().getTime() - 1;
416 }
417
418 /**
419 * Returns a string representing the week (e.g. "Week 9, 2002").
420 *
421 * TODO: look at internationalisation.
422 *
423 * @return A string representing the week.
424 */
425 public String toString() {
426 return "Week " + this.week + ", " + this.year;
427 }
428
429 /**
430 * Tests the equality of this Week object to an arbitrary object. Returns
431 * true if the target is a Week instance representing the same week as this
432 * object. In all other cases, returns false.
433 *
434 * @param obj the object (<code>null</code> permitted).
435 *
436 * @return <code>true</code> if week and year of this and object are the
437 * same.
438 */
439 public boolean equals(Object obj) {
440
441 if (obj == this) {
442 return true;
443 }
444 if (!(obj instanceof Week)) {
445 return false;
446 }
447 Week that = (Week) obj;
448 if (this.week != that.week) {
449 return false;
450 }
451 if (this.year != that.year) {
452 return false;
453 }
454 return true;
455
456 }
457
458 /**
459 * Returns a hash code for this object instance. The approach described by
460 * Joshua Bloch in "Effective Java" has been used here:
461 * <p>
462 * <code>http://developer.java.sun.com/developer/Books/effectivejava
463 * /Chapter3.pdf</code>
464 *
465 * @return A hash code.
466 */
467 public int hashCode() {
468 int result = 17;
469 result = 37 * result + this.week;
470 result = 37 * result + this.year;
471 return result;
472 }
473
474 /**
475 * Returns an integer indicating the order of this Week object relative to
476 * the specified object:
477 *
478 * negative == before, zero == same, positive == after.
479 *
480 * @param o1 the object to compare.
481 *
482 * @return negative == before, zero == same, positive == after.
483 */
484 public int compareTo(Object o1) {
485
486 int result;
487
488 // CASE 1 : Comparing to another Week object
489 // --------------------------------------------
490 if (o1 instanceof Week) {
491 Week w = (Week) o1;
492 result = this.year - w.getYear().getYear();
493 if (result == 0) {
494 result = this.week - w.getWeek();
495 }
496 }
497
498 // CASE 2 : Comparing to another TimePeriod object
499 // -----------------------------------------------
500 else if (o1 instanceof RegularTimePeriod) {
501 // more difficult case - evaluate later...
502 result = 0;
503 }
504
505 // CASE 3 : Comparing to a non-TimePeriod object
506 // ---------------------------------------------
507 else {
508 // consider time periods to be ordered after general objects
509 result = 1;
510 }
511
512 return result;
513
514 }
515
516 /**
517 * Parses the string argument as a week.
518 * <P>
519 * This method is required to accept the format "YYYY-Wnn". It will also
520 * accept "Wnn-YYYY". Anything else, at the moment, is a bonus.
521 *
522 * @param s string to parse.
523 *
524 * @return <code>null</code> if the string is not parseable, the week
525 * otherwise.
526 */
527 public static Week parseWeek(String s) {
528
529 Week result = null;
530 if (s != null) {
531
532 // trim whitespace from either end of the string
533 s = s.trim();
534
535 int i = Week.findSeparator(s);
536 if (i != -1) {
537 String s1 = s.substring(0, i).trim();
538 String s2 = s.substring(i + 1, s.length()).trim();
539
540 Year y = Week.evaluateAsYear(s1);
541 int w;
542 if (y != null) {
543 w = Week.stringToWeek(s2);
544 if (w == -1) {
545 throw new TimePeriodFormatException(
546 "Can't evaluate the week.");
547 }
548 result = new Week(w, y);
549 }
550 else {
551 y = Week.evaluateAsYear(s2);
552 if (y != null) {
553 w = Week.stringToWeek(s1);
554 if (w == -1) {
555 throw new TimePeriodFormatException(
556 "Can't evaluate the week.");
557 }
558 result = new Week(w, y);
559 }
560 else {
561 throw new TimePeriodFormatException(
562 "Can't evaluate the year.");
563 }
564 }
565
566 }
567 else {
568 throw new TimePeriodFormatException(
569 "Could not find separator.");
570 }
571
572 }
573 return result;
574
575 }
576
577 /**
578 * Finds the first occurrence of ' ', '-', ',' or '.'
579 *
580 * @param s the string to parse.
581 *
582 * @return <code>-1</code> if none of the characters was found, the
583 * index of the first occurrence otherwise.
584 */
585 private static int findSeparator(String s) {
586
587 int result = s.indexOf('-');
588 if (result == -1) {
589 result = s.indexOf(',');
590 }
591 if (result == -1) {
592 result = s.indexOf(' ');
593 }
594 if (result == -1) {
595 result = s.indexOf('.');
596 }
597 return result;
598 }
599
600 /**
601 * Creates a year from a string, or returns null (format exceptions
602 * suppressed).
603 *
604 * @param s string to parse.
605 *
606 * @return <code>null</code> if the string is not parseable, the year
607 * otherwise.
608 */
609 private static Year evaluateAsYear(String s) {
610
611 Year result = null;
612 try {
613 result = Year.parseYear(s);
614 }
615 catch (TimePeriodFormatException e) {
616 // suppress
617 }
618 return result;
619
620 }
621
622 /**
623 * Converts a string to a week.
624 *
625 * @param s the string to parse.
626 * @return <code>-1</code> if the string does not contain a week number,
627 * the number of the week otherwise.
628 */
629 private static int stringToWeek(String s) {
630
631 int result = -1;
632 s = s.replace('W', ' ');
633 s = s.trim();
634 try {
635 result = Integer.parseInt(s);
636 if ((result < 1) || (result > LAST_WEEK_IN_YEAR)) {
637 result = -1;
638 }
639 }
640 catch (NumberFormatException e) {
641 // suppress
642 }
643 return result;
644
645 }
646
647 }