1 /*
2 * Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 /*
27 * (C) Copyright Taligent, Inc. 1996 - All Rights Reserved
28 * (C) Copyright IBM Corp. 1996 - All Rights Reserved
29 *
30 * The original version of this source code and documentation is copyrighted
31 * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
32 * materials are provided under terms of a License Agreement between Taligent
33 * and Sun. This technology is protected by multiple US and International
34 * patents. This notice and attribution to Taligent may not be removed.
35 * Taligent is a registered trademark of Taligent, Inc.
36 *
37 */
38
39 package java.text;
40
41 import java.io.InvalidObjectException;
42 import java.text.spi.DateFormatProvider;
43 import java.util.Calendar;
44 import java.util.Date;
45 import java.util.GregorianCalendar;
46 import java.util.HashMap;
47 import java.util.Locale;
48 import java.util.Map;
49 import java.util.MissingResourceException;
50 import java.util.ResourceBundle;
51 import java.util.TimeZone;
52 import java.util.spi.LocaleServiceProvider;
53 import sun.util.locale.provider.LocaleProviderAdapter;
54 import sun.util.locale.provider.LocaleServiceProviderPool;
55
56 /**
57 * {@code DateFormat} is an abstract class for date/time formatting subclasses which
58 * formats and parses dates or time in a language-independent manner.
59 * The date/time formatting subclass, such as {@link SimpleDateFormat}, allows for
60 * formatting (i.e., date → text), parsing (text → date), and
61 * normalization. The date is represented as a <code>Date</code> object or
62 * as the milliseconds since January 1, 1970, 00:00:00 GMT.
63 *
64 * <p>{@code DateFormat} provides many class methods for obtaining default date/time
65 * formatters based on the default or a given locale and a number of formatting
66 * styles. The formatting styles include {@link #FULL}, {@link #LONG}, {@link #MEDIUM}, and {@link #SHORT}. More
67 * detail and examples of using these styles are provided in the method
68 * descriptions.
69 *
70 * <p>{@code DateFormat} helps you to format and parse dates for any locale.
71 * Your code can be completely independent of the locale conventions for
72 * months, days of the week, or even the calendar format: lunar vs. solar.
73 *
74 * <p>To format a date for the current Locale, use one of the
75 * static factory methods:
76 * <blockquote>
77 * <pre>{@code
78 * myString = DateFormat.getDateInstance().format(myDate);
79 * }</pre>
80 * </blockquote>
81 * <p>If you are formatting multiple dates, it is
82 * more efficient to get the format and use it multiple times so that
83 * the system doesn't have to fetch the information about the local
84 * language and country conventions multiple times.
85 * <blockquote>
86 * <pre>{@code
87 * DateFormat df = DateFormat.getDateInstance();
88 * for (int i = 0; i < myDate.length; ++i) {
89 * output.println(df.format(myDate[i]) + "; ");
90 * }
91 * }</pre>
92 * </blockquote>
93 * <p>To format a date for a different Locale, specify it in the
94 * call to {@link #getDateInstance(int, Locale) getDateInstance()}.
95 * <blockquote>
96 * <pre>{@code
97 * DateFormat df = DateFormat.getDateInstance(DateFormat.LONG, Locale.FRANCE);
98 * }</pre>
99 * </blockquote>
100 * <p>You can use a DateFormat to parse also.
101 * <blockquote>
102 * <pre>{@code
103 * myDate = df.parse(myString);
104 * }</pre>
105 * </blockquote>
106 * <p>Use {@code getDateInstance} to get the normal date format for that country.
107 * There are other static factory methods available.
108 * Use {@code getTimeInstance} to get the time format for that country.
109 * Use {@code getDateTimeInstance} to get a date and time format. You can pass in
110 * different options to these factory methods to control the length of the
111 * result; from {@link #SHORT} to {@link #MEDIUM} to {@link #LONG} to {@link #FULL}. The exact result depends
112 * on the locale, but generally:
113 * <ul><li>{@link #SHORT} is completely numeric, such as {@code 12.13.52} or {@code 3:30pm}
114 * <li>{@link #MEDIUM} is longer, such as {@code Jan 12, 1952}
115 * <li>{@link #LONG} is longer, such as {@code January 12, 1952} or {@code 3:30:32pm}
116 * <li>{@link #FULL} is pretty completely specified, such as
117 * {@code Tuesday, April 12, 1952 AD or 3:30:42pm PST}.
118 * </ul>
119 *
120 * <p>You can also set the time zone on the format if you wish.
121 * If you want even more control over the format or parsing,
122 * (or want to give your users more control),
123 * you can try casting the {@code DateFormat} you get from the factory methods
124 * to a {@link SimpleDateFormat}. This will work for the majority
125 * of countries; just remember to put it in a {@code try} block in case you
126 * encounter an unusual one.
127 *
128 * <p>You can also use forms of the parse and format methods with
129 * {@link ParsePosition} and {@link FieldPosition} to
130 * allow you to
131 * <ul><li>progressively parse through pieces of a string.
132 * <li>align any particular field, or find out where it is for selection
133 * on the screen.
134 * </ul>
135 *
136 * <h3><a name="synchronization">Synchronization</a></h3>
137 *
138 * <p>
139 * Date formats are not synchronized.
140 * It is recommended to create separate format instances for each thread.
141 * If multiple threads access a format concurrently, it must be synchronized
142 * externally.
143 *
144 * @implSpec
145 * <ul><li>The {@link #format(Date, StringBuffer, FieldPosition)} and
146 * {@link #parse(String, ParsePosition)} methods may throw
147 * {@code NullPointerException}, if any of their parameter is {@code null}.
148 * The subclass may provide its own implementation and specification about
149 * {@code NullPointerException}.</li>
150 * <li>The {@link #setCalendar(Calendar)}, {@link
151 * #setNumberFormat(NumberFormat)} and {@link #setTimeZone(TimeZone)} methods
152 * do not throw {@code NullPointerException} when their parameter is
153 * {@code null}, but any subsequent operations on the same instance may throw
154 * {@code NullPointerException}.</li>
155 * <li>The {@link #getCalendar()}, {@link #getNumberFormat()} and
156 * {@link getTimeZone()} methods may return {@code null}, if the respective
157 * values of this instance is set to {@code null} through the corresponding
158 * setter methods. For Example: {@link #getTimeZone()} may return {@code null},
159 * if the {@code TimeZone} value of this instance is set as
160 * {@link #setTimeZone(java.util.TimeZone) setTimeZone(null)}.</li>
161 * </ul>
162 *
163 * @see Format
164 * @see NumberFormat
165 * @see SimpleDateFormat
166 * @see java.util.Calendar
167 * @see java.util.GregorianCalendar
168 * @see java.util.TimeZone
169 * @author Mark Davis, Chen-Lieh Huang, Alan Liu
170 */
171 public abstract class DateFormat extends Format {
172
173 /**
174 * The {@link Calendar} instance used for calculating the date-time fields
175 * and the instant of time. This field is used for both formatting and
176 * parsing.
177 *
178 * <p>Subclasses should initialize this field to a {@link Calendar}
179 * appropriate for the {@link Locale} associated with this
180 * <code>DateFormat</code>.
181 * @serial
182 */
183 protected Calendar calendar;
184
185 /**
186 * The number formatter that <code>DateFormat</code> uses to format numbers
187 * in dates and times. Subclasses should initialize this to a number format
188 * appropriate for the locale associated with this <code>DateFormat</code>.
189 * @serial
190 */
191 protected NumberFormat numberFormat;
192
193 /**
194 * Useful constant for ERA field alignment.
195 * Used in FieldPosition of date/time formatting.
196 */
197 public static final int ERA_FIELD = 0;
198 /**
199 * Useful constant for YEAR field alignment.
200 * Used in FieldPosition of date/time formatting.
201 */
202 public static final int YEAR_FIELD = 1;
203 /**
204 * Useful constant for MONTH field alignment.
205 * Used in FieldPosition of date/time formatting.
206 */
207 public static final int MONTH_FIELD = 2;
208 /**
209 * Useful constant for DATE field alignment.
210 * Used in FieldPosition of date/time formatting.
211 */
212 public static final int DATE_FIELD = 3;
213 /**
214 * Useful constant for one-based HOUR_OF_DAY field alignment.
215 * Used in FieldPosition of date/time formatting.
216 * HOUR_OF_DAY1_FIELD is used for the one-based 24-hour clock.
217 * For example, 23:59 + 01:00 results in 24:59.
218 */
219 public static final int HOUR_OF_DAY1_FIELD = 4;
220 /**
221 * Useful constant for zero-based HOUR_OF_DAY field alignment.
222 * Used in FieldPosition of date/time formatting.
223 * HOUR_OF_DAY0_FIELD is used for the zero-based 24-hour clock.
224 * For example, 23:59 + 01:00 results in 00:59.
225 */
226 public static final int HOUR_OF_DAY0_FIELD = 5;
227 /**
228 * Useful constant for MINUTE field alignment.
229 * Used in FieldPosition of date/time formatting.
230 */
231 public static final int MINUTE_FIELD = 6;
232 /**
233 * Useful constant for SECOND field alignment.
234 * Used in FieldPosition of date/time formatting.
235 */
236 public static final int SECOND_FIELD = 7;
237 /**
238 * Useful constant for MILLISECOND field alignment.
239 * Used in FieldPosition of date/time formatting.
240 */
241 public static final int MILLISECOND_FIELD = 8;
242 /**
243 * Useful constant for DAY_OF_WEEK field alignment.
244 * Used in FieldPosition of date/time formatting.
245 */
246 public static final int DAY_OF_WEEK_FIELD = 9;
247 /**
248 * Useful constant for DAY_OF_YEAR field alignment.
249 * Used in FieldPosition of date/time formatting.
250 */
251 public static final int DAY_OF_YEAR_FIELD = 10;
252 /**
253 * Useful constant for DAY_OF_WEEK_IN_MONTH field alignment.
254 * Used in FieldPosition of date/time formatting.
255 */
256 public static final int DAY_OF_WEEK_IN_MONTH_FIELD = 11;
257 /**
258 * Useful constant for WEEK_OF_YEAR field alignment.
259 * Used in FieldPosition of date/time formatting.
260 */
261 public static final int WEEK_OF_YEAR_FIELD = 12;
262 /**
263 * Useful constant for WEEK_OF_MONTH field alignment.
264 * Used in FieldPosition of date/time formatting.
265 */
266 public static final int WEEK_OF_MONTH_FIELD = 13;
267 /**
268 * Useful constant for AM_PM field alignment.
269 * Used in FieldPosition of date/time formatting.
270 */
271 public static final int AM_PM_FIELD = 14;
272 /**
273 * Useful constant for one-based HOUR field alignment.
274 * Used in FieldPosition of date/time formatting.
275 * HOUR1_FIELD is used for the one-based 12-hour clock.
276 * For example, 11:30 PM + 1 hour results in 12:30 AM.
277 */
278 public static final int HOUR1_FIELD = 15;
279 /**
280 * Useful constant for zero-based HOUR field alignment.
281 * Used in FieldPosition of date/time formatting.
282 * HOUR0_FIELD is used for the zero-based 12-hour clock.
283 * For example, 11:30 PM + 1 hour results in 00:30 AM.
284 */
285 public static final int HOUR0_FIELD = 16;
286 /**
287 * Useful constant for TIMEZONE field alignment.
288 * Used in FieldPosition of date/time formatting.
289 */
290 public static final int TIMEZONE_FIELD = 17;
291
292 // Proclaim serial compatibility with 1.1 FCS
293 private static final long serialVersionUID = 7218322306649953788L;
294
295 /**
296 * Overrides Format.
297 * Formats a time object into a time string. Examples of time objects
298 * are a time value expressed in milliseconds and a Date object.
299 * @param obj must be a Number or a Date.
300 * @param toAppendTo the string buffer for the returning time string.
301 * @return the string buffer passed in as toAppendTo, with formatted text appended.
302 * @param fieldPosition keeps track of the position of the field
303 * within the returned string.
304 * On input: an alignment field,
305 * if desired. On output: the offsets of the alignment field. For
306 * example, given a time text "1996.07.10 AD at 15:08:56 PDT",
307 * if the given fieldPosition is DateFormat.YEAR_FIELD, the
308 * begin index and end index of fieldPosition will be set to
309 * 0 and 4, respectively.
310 * Notice that if the same time field appears
311 * more than once in a pattern, the fieldPosition will be set for the first
312 * occurrence of that time field. For instance, formatting a Date to
313 * the time string "1 PM PDT (Pacific Daylight Time)" using the pattern
314 * "h a z (zzzz)" and the alignment field DateFormat.TIMEZONE_FIELD,
315 * the begin index and end index of fieldPosition will be set to
316 * 5 and 8, respectively, for the first occurrence of the timezone
317 * pattern character 'z'.
318 * @exception IllegalArgumentException if the {@code Format} cannot format
319 * the given {@code obj}.
320 * @see java.text.Format
321 */
322 public final StringBuffer format(Object obj, StringBuffer toAppendTo,
323 FieldPosition fieldPosition)
324 {
325 if (obj instanceof Date)
326 return format( (Date)obj, toAppendTo, fieldPosition );
327 else if (obj instanceof Number)
328 return format( new Date(((Number)obj).longValue()),
329 toAppendTo, fieldPosition );
330 else
331 throw new IllegalArgumentException("Cannot format given Object as a Date");
332 }
333
334 /**
335 * Formats a Date into a date/time string.
336 * @param date a Date to be formatted into a date/time string.
337 * @param toAppendTo the string buffer for the returning date/time string.
338 * @param fieldPosition keeps track of the position of the field
339 * within the returned string.
340 * On input: an alignment field,
341 * if desired. On output: the offsets of the alignment field. For
342 * example, given a time text "1996.07.10 AD at 15:08:56 PDT",
343 * if the given fieldPosition is DateFormat.YEAR_FIELD, the
344 * begin index and end index of fieldPosition will be set to
345 * 0 and 4, respectively.
346 * Notice that if the same time field appears
347 * more than once in a pattern, the fieldPosition will be set for the first
348 * occurrence of that time field. For instance, formatting a Date to
349 * the time string "1 PM PDT (Pacific Daylight Time)" using the pattern
350 * "h a z (zzzz)" and the alignment field DateFormat.TIMEZONE_FIELD,
351 * the begin index and end index of fieldPosition will be set to
352 * 5 and 8, respectively, for the first occurrence of the timezone
353 * pattern character 'z'.
354 * @return the string buffer passed in as toAppendTo, with formatted text appended.
355 */
356 public abstract StringBuffer format(Date date, StringBuffer toAppendTo,
357 FieldPosition fieldPosition);
358
359 /**
360 * Formats a Date into a date/time string.
361 * @param date the time value to be formatted into a time string.
362 * @return the formatted time string.
363 */
364 public final String format(Date date)
365 {
366 return format(date, new StringBuffer(),
367 DontCareFieldPosition.INSTANCE).toString();
368 }
369
370 /**
371 * Parses text from the beginning of the given string to produce a date.
372 * The method may not use the entire text of the given string.
373 * <p>
374 * See the {@link #parse(String, ParsePosition)} method for more information
375 * on date parsing.
376 *
377 * @param source A <code>String</code> whose beginning should be parsed.
378 * @return A <code>Date</code> parsed from the string.
379 * @exception ParseException if the beginning of the specified string
380 * cannot be parsed.
381 */
382 public Date parse(String source) throws ParseException
383 {
384 ParsePosition pos = new ParsePosition(0);
385 Date result = parse(source, pos);
386 if (pos.index == 0)
387 throw new ParseException("Unparseable date: \"" + source + "\"" ,
388 pos.errorIndex);
389 return result;
390 }
391
392 /**
393 * Parse a date/time string according to the given parse position. For
394 * example, a time text {@code "07/10/96 4:5 PM, PDT"} will be parsed into a {@code Date}
395 * that is equivalent to {@code Date(837039900000L)}.
396 *
397 * <p> By default, parsing is lenient: If the input is not in the form used
398 * by this object's format method but can still be parsed as a date, then
399 * the parse succeeds. Clients may insist on strict adherence to the
400 * format by calling {@link #setLenient(boolean) setLenient(false)}.
401 *
402 * <p>This parsing operation uses the {@link #calendar} to produce
403 * a {@code Date}. As a result, the {@code calendar}'s date-time
404 * fields and the {@code TimeZone} value may have been
405 * overwritten, depending on subclass implementations. Any {@code
406 * TimeZone} value that has previously been set by a call to
407 * {@link #setTimeZone(java.util.TimeZone) setTimeZone} may need
408 * to be restored for further operations.
409 *
410 * @param source The date/time string to be parsed
411 *
412 * @param pos On input, the position at which to start parsing; on
413 * output, the position at which parsing terminated, or the
414 * start position if the parse failed.
415 *
416 * @return A {@code Date}, or {@code null} if the input could not be parsed
417 */
418 public abstract Date parse(String source, ParsePosition pos);
419
420 /**
421 * Parses text from a string to produce a <code>Date</code>.
422 * <p>
423 * The method attempts to parse text starting at the index given by
424 * <code>pos</code>.
425 * If parsing succeeds, then the index of <code>pos</code> is updated
426 * to the index after the last character used (parsing does not necessarily
427 * use all characters up to the end of the string), and the parsed
428 * date is returned. The updated <code>pos</code> can be used to
429 * indicate the starting point for the next call to this method.
430 * If an error occurs, then the index of <code>pos</code> is not
431 * changed, the error index of <code>pos</code> is set to the index of
432 * the character where the error occurred, and null is returned.
433 * <p>
434 * See the {@link #parse(String, ParsePosition)} method for more information
435 * on date parsing.
436 *
437 * @param source A <code>String</code>, part of which should be parsed.
438 * @param pos A <code>ParsePosition</code> object with index and error
439 * index information as described above.
440 * @return A <code>Date</code> parsed from the string. In case of
441 * error, returns null.
442 * @throws NullPointerException if {@code source} or {@code pos} is null.
443 */
444 public Object parseObject(String source, ParsePosition pos) {
445 return parse(source, pos);
446 }
447
448 /**
449 * Constant for full style pattern.
450 */
451 public static final int FULL = 0;
452 /**
453 * Constant for long style pattern.
454 */
455 public static final int LONG = 1;
456 /**
457 * Constant for medium style pattern.
458 */
459 public static final int MEDIUM = 2;
460 /**
461 * Constant for short style pattern.
462 */
463 public static final int SHORT = 3;
464 /**
465 * Constant for default style pattern. Its value is MEDIUM.
466 */
467 public static final int DEFAULT = MEDIUM;
468
469 /**
470 * Gets the time formatter with the default formatting style
471 * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
472 * <p>This is equivalent to calling
473 * {@link #getTimeInstance(int, Locale) getTimeInstance(DEFAULT,
474 * Locale.getDefault(Locale.Category.FORMAT))}.
475 * @see java.util.Locale#getDefault(java.util.Locale.Category)
476 * @see java.util.Locale.Category#FORMAT
477 * @return a time formatter.
478 */
479 public static final DateFormat getTimeInstance()
480 {
481 return get(DEFAULT, 0, 1, Locale.getDefault(Locale.Category.FORMAT));
482 }
483
484 /**
485 * Gets the time formatter with the given formatting style
486 * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
487 * <p>This is equivalent to calling
488 * {@link #getTimeInstance(int, Locale) getTimeInstance(style,
489 * Locale.getDefault(Locale.Category.FORMAT))}.
490 * @see java.util.Locale#getDefault(java.util.Locale.Category)
491 * @see java.util.Locale.Category#FORMAT
492 * @param style the given formatting style. For example,
493 * SHORT for "h:mm a" in the US locale.
494 * @return a time formatter.
495 */
496 public static final DateFormat getTimeInstance(int style)
497 {
498 return get(style, 0, 1, Locale.getDefault(Locale.Category.FORMAT));
499 }
500
501 /**
502 * Gets the time formatter with the given formatting style
503 * for the given locale.
504 * @param style the given formatting style. For example,
505 * SHORT for "h:mm a" in the US locale.
506 * @param aLocale the given locale.
507 * @return a time formatter.
508 */
509 public static final DateFormat getTimeInstance(int style,
510 Locale aLocale)
511 {
512 return get(style, 0, 1, aLocale);
513 }
514
515 /**
516 * Gets the date formatter with the default formatting style
517 * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
518 * <p>This is equivalent to calling
519 * {@link #getDateInstance(int, Locale) getDateInstance(DEFAULT,
520 * Locale.getDefault(Locale.Category.FORMAT))}.
521 * @see java.util.Locale#getDefault(java.util.Locale.Category)
522 * @see java.util.Locale.Category#FORMAT
523 * @return a date formatter.
524 */
525 public static final DateFormat getDateInstance()
526 {
527 return get(0, DEFAULT, 2, Locale.getDefault(Locale.Category.FORMAT));
528 }
529
530 /**
531 * Gets the date formatter with the given formatting style
532 * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
533 * <p>This is equivalent to calling
534 * {@link #getDateInstance(int, Locale) getDateInstance(style,
535 * Locale.getDefault(Locale.Category.FORMAT))}.
536 * @see java.util.Locale#getDefault(java.util.Locale.Category)
537 * @see java.util.Locale.Category#FORMAT
538 * @param style the given formatting style. For example,
539 * SHORT for "M/d/yy" in the US locale.
540 * @return a date formatter.
541 */
542 public static final DateFormat getDateInstance(int style)
543 {
544 return get(0, style, 2, Locale.getDefault(Locale.Category.FORMAT));
545 }
546
547 /**
548 * Gets the date formatter with the given formatting style
549 * for the given locale.
550 * @param style the given formatting style. For example,
551 * SHORT for "M/d/yy" in the US locale.
552 * @param aLocale the given locale.
553 * @return a date formatter.
554 */
555 public static final DateFormat getDateInstance(int style,
556 Locale aLocale)
557 {
558 return get(0, style, 2, aLocale);
559 }
560
561 /**
562 * Gets the date/time formatter with the default formatting style
563 * for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
564 * <p>This is equivalent to calling
565 * {@link #getDateTimeInstance(int, int, Locale) getDateTimeInstance(DEFAULT,
566 * DEFAULT, Locale.getDefault(Locale.Category.FORMAT))}.
567 * @see java.util.Locale#getDefault(java.util.Locale.Category)
568 * @see java.util.Locale.Category#FORMAT
569 * @return a date/time formatter.
570 */
571 public static final DateFormat getDateTimeInstance()
572 {
573 return get(DEFAULT, DEFAULT, 3, Locale.getDefault(Locale.Category.FORMAT));
574 }
575
576 /**
577 * Gets the date/time formatter with the given date and time
578 * formatting styles for the default {@link java.util.Locale.Category#FORMAT FORMAT} locale.
579 * <p>This is equivalent to calling
580 * {@link #getDateTimeInstance(int, int, Locale) getDateTimeInstance(dateStyle,
581 * timeStyle, Locale.getDefault(Locale.Category.FORMAT))}.
582 * @see java.util.Locale#getDefault(java.util.Locale.Category)
583 * @see java.util.Locale.Category#FORMAT
584 * @param dateStyle the given date formatting style. For example,
585 * SHORT for "M/d/yy" in the US locale.
586 * @param timeStyle the given time formatting style. For example,
587 * SHORT for "h:mm a" in the US locale.
588 * @return a date/time formatter.
589 */
590 public static final DateFormat getDateTimeInstance(int dateStyle,
591 int timeStyle)
592 {
593 return get(timeStyle, dateStyle, 3, Locale.getDefault(Locale.Category.FORMAT));
594 }
595
596 /**
597 * Gets the date/time formatter with the given formatting styles
598 * for the given locale.
599 * @param dateStyle the given date formatting style.
600 * @param timeStyle the given time formatting style.
601 * @param aLocale the given locale.
602 * @return a date/time formatter.
603 */
604 public static final DateFormat
605 getDateTimeInstance(int dateStyle, int timeStyle, Locale aLocale)
606 {
607 return get(timeStyle, dateStyle, 3, aLocale);
608 }
609
610 /**
611 * Get a default date/time formatter that uses the SHORT style for both the
612 * date and the time.
613 *
614 * @return a date/time formatter
615 */
616 public static final DateFormat getInstance() {
617 return getDateTimeInstance(SHORT, SHORT);
618 }
619
620 /**
621 * Returns an array of all locales for which the
622 * <code>get*Instance</code> methods of this class can return
623 * localized instances.
624 * The returned array represents the union of locales supported by the Java
625 * runtime and by installed
626 * {@link java.text.spi.DateFormatProvider DateFormatProvider} implementations.
627 * It must contain at least a <code>Locale</code> instance equal to
628 * {@link java.util.Locale#US Locale.US}.
629 *
630 * @return An array of locales for which localized
631 * <code>DateFormat</code> instances are available.
632 */
633 public static Locale[] getAvailableLocales()
634 {
635 LocaleServiceProviderPool pool =
636 LocaleServiceProviderPool.getPool(DateFormatProvider.class);
637 return pool.getAvailableLocales();
638 }
639
640 /**
641 * Set the calendar to be used by this date format. Initially, the default
642 * calendar for the specified or default locale is used.
643 *
644 * <p>Any {@link java.util.TimeZone TimeZone} and {@linkplain
645 * #isLenient() leniency} values that have previously been set are
646 * overwritten by {@code newCalendar}'s values.
647 *
648 * @param newCalendar the new {@code Calendar} to be used by the date format
649 */
650 public void setCalendar(Calendar newCalendar)
651 {
652 this.calendar = newCalendar;
653 }
654
655 /**
656 * Gets the calendar associated with this date/time formatter.
657 *
658 * @return the calendar associated with this date/time formatter.
659 */
660 public Calendar getCalendar()
661 {
662 return calendar;
663 }
664
665 /**
666 * Allows you to set the number formatter.
667 * @param newNumberFormat the given new NumberFormat.
668 */
669 public void setNumberFormat(NumberFormat newNumberFormat)
670 {
671 this.numberFormat = newNumberFormat;
672 }
673
674 /**
675 * Gets the number formatter which this date/time formatter uses to
676 * format and parse a time.
677 * @return the number formatter which this date/time formatter uses.
678 */
679 public NumberFormat getNumberFormat()
680 {
681 return numberFormat;
682 }
683
684 /**
685 * Sets the time zone for the calendar of this {@code DateFormat} object.
686 * This method is equivalent to the following call.
687 * <blockquote><pre>{@code
688 * getCalendar().setTimeZone(zone)
689 * }</pre></blockquote>
690 *
691 * <p>The {@code TimeZone} set by this method is overwritten by a
692 * {@link #setCalendar(java.util.Calendar) setCalendar} call.
693 *
694 * <p>The {@code TimeZone} set by this method may be overwritten as
695 * a result of a call to the parse method.
696 *
697 * @param zone the given new time zone.
698 */
699 public void setTimeZone(TimeZone zone)
700 {
701 calendar.setTimeZone(zone);
702 }
703
704 /**
705 * Gets the time zone.
706 * This method is equivalent to the following call.
707 * <blockquote><pre>{@code
708 * getCalendar().getTimeZone()
709 * }</pre></blockquote>
710 *
711 * @return the time zone associated with the calendar of DateFormat.
712 */
713 public TimeZone getTimeZone()
714 {
715 return calendar.getTimeZone();
716 }
717
718 /**
719 * Specify whether or not date/time parsing is to be lenient. With
720 * lenient parsing, the parser may use heuristics to interpret inputs that
721 * do not precisely match this object's format. With strict parsing,
722 * inputs must match this object's format.
723 *
724 * <p>This method is equivalent to the following call.
725 * <blockquote><pre>{@code
726 * getCalendar().setLenient(lenient)
727 * }</pre></blockquote>
728 *
729 * <p>This leniency value is overwritten by a call to {@link
730 * #setCalendar(java.util.Calendar) setCalendar()}.
731 *
732 * @param lenient when {@code true}, parsing is lenient
733 * @see java.util.Calendar#setLenient(boolean)
734 */
735 public void setLenient(boolean lenient)
736 {
737 calendar.setLenient(lenient);
738 }
739
740 /**
741 * Tell whether date/time parsing is to be lenient.
742 * This method is equivalent to the following call.
743 * <blockquote><pre>{@code
744 * getCalendar().isLenient()
745 * }</pre></blockquote>
746 *
747 * @return {@code true} if the {@link #calendar} is lenient;
748 * {@code false} otherwise.
749 * @see java.util.Calendar#isLenient()
750 */
751 public boolean isLenient()
752 {
753 return calendar.isLenient();
754 }
755
756 /**
757 * Overrides hashCode
758 */
759 public int hashCode() {
760 return numberFormat.hashCode();
761 // just enough fields for a reasonable distribution
762 }
763
764 /**
765 * Overrides equals
766 */
767 public boolean equals(Object obj) {
768 if (this == obj) return true;
769 if (obj == null || getClass() != obj.getClass()) return false;
770 DateFormat other = (DateFormat) obj;
771 return (// calendar.equivalentTo(other.calendar) // THIS API DOESN'T EXIST YET!
772 calendar.getFirstDayOfWeek() == other.calendar.getFirstDayOfWeek() &&
773 calendar.getMinimalDaysInFirstWeek() == other.calendar.getMinimalDaysInFirstWeek() &&
774 calendar.isLenient() == other.calendar.isLenient() &&
775 calendar.getTimeZone().equals(other.calendar.getTimeZone()) &&
776 numberFormat.equals(other.numberFormat));
777 }
778
779 /**
780 * Overrides Cloneable
781 */
782 public Object clone()
783 {
784 DateFormat other = (DateFormat) super.clone();
785 other.calendar = (Calendar) calendar.clone();
786 other.numberFormat = (NumberFormat) numberFormat.clone();
787 return other;
788 }
789
790 /**
791 * Creates a DateFormat with the given time and/or date style in the given
792 * locale.
793 * @param timeStyle a value from 0 to 3 indicating the time format,
794 * ignored if flags is 2
795 * @param dateStyle a value from 0 to 3 indicating the time format,
796 * ignored if flags is 1
797 * @param flags either 1 for a time format, 2 for a date format,
798 * or 3 for a date/time format
799 * @param loc the locale for the format
800 */
801 private static DateFormat get(int timeStyle, int dateStyle,
802 int flags, Locale loc) {
803 if ((flags & 1) != 0) {
804 if (timeStyle < 0 || timeStyle > 3) {
805 throw new IllegalArgumentException("Illegal time style " + timeStyle);
806 }
807 } else {
808 timeStyle = -1;
809 }
810 if ((flags & 2) != 0) {
811 if (dateStyle < 0 || dateStyle > 3) {
812 throw new IllegalArgumentException("Illegal date style " + dateStyle);
813 }
814 } else {
815 dateStyle = -1;
816 }
817
818 LocaleProviderAdapter adapter = LocaleProviderAdapter.getAdapter(DateFormatProvider.class, loc);
819 DateFormat dateFormat = get(adapter, timeStyle, dateStyle, loc);
820 if (dateFormat == null) {
821 dateFormat = get(LocaleProviderAdapter.forJRE(), timeStyle, dateStyle, loc);
822 }
823 return dateFormat;
824 }
825
826 private static DateFormat get(LocaleProviderAdapter adapter, int timeStyle, int dateStyle, Locale loc) {
827 DateFormatProvider provider = adapter.getDateFormatProvider();
828 DateFormat dateFormat;
829 if (timeStyle == -1) {
830 dateFormat = provider.getDateInstance(dateStyle, loc);
831 } else {
832 if (dateStyle == -1) {
833 dateFormat = provider.getTimeInstance(timeStyle, loc);
834 } else {
835 dateFormat = provider.getDateTimeInstance(dateStyle, timeStyle, loc);
836 }
837 }
838 return dateFormat;
839 }
840
841 /**
842 * Create a new date format.
843 */
844 protected DateFormat() {}
845
846 /**
847 * Defines constants that are used as attribute keys in the
848 * <code>AttributedCharacterIterator</code> returned
849 * from <code>DateFormat.formatToCharacterIterator</code> and as
850 * field identifiers in <code>FieldPosition</code>.
851 * <p>
852 * The class also provides two methods to map
853 * between its constants and the corresponding Calendar constants.
854 *
855 * @since 1.4
856 * @see java.util.Calendar
857 */
858 public static class Field extends Format.Field {
859
860 // Proclaim serial compatibility with 1.4 FCS
861 private static final long serialVersionUID = 7441350119349544720L;
862
863 // table of all instances in this class, used by readResolve
864 private static final Map<String, Field> instanceMap = new HashMap<>(18);
865 // Maps from Calendar constant (such as Calendar.ERA) to Field
866 // constant (such as Field.ERA).
867 private static final Field[] calendarToFieldMapping =
868 new Field[Calendar.FIELD_COUNT];
869
870 /** Calendar field. */
871 private int calendarField;
872
873 /**
874 * Returns the <code>Field</code> constant that corresponds to
875 * the <code>Calendar</code> constant <code>calendarField</code>.
876 * If there is no direct mapping between the <code>Calendar</code>
877 * constant and a <code>Field</code>, null is returned.
878 *
879 * @throws IllegalArgumentException if <code>calendarField</code> is
880 * not the value of a <code>Calendar</code> field constant.
881 * @param calendarField Calendar field constant
882 * @return Field instance representing calendarField.
883 * @see java.util.Calendar
884 */
885 public static Field ofCalendarField(int calendarField) {
886 if (calendarField < 0 || calendarField >=
887 calendarToFieldMapping.length) {
888 throw new IllegalArgumentException("Unknown Calendar constant "
889 + calendarField);
890 }
891 return calendarToFieldMapping[calendarField];
892 }
893
894 /**
895 * Creates a <code>Field</code>.
896 *
897 * @param name the name of the <code>Field</code>
898 * @param calendarField the <code>Calendar</code> constant this
899 * <code>Field</code> corresponds to; any value, even one
900 * outside the range of legal <code>Calendar</code> values may
901 * be used, but <code>-1</code> should be used for values
902 * that don't correspond to legal <code>Calendar</code> values
903 */
904 protected Field(String name, int calendarField) {
905 super(name);
906 this.calendarField = calendarField;
907 if (this.getClass() == DateFormat.Field.class) {
908 instanceMap.put(name, this);
909 if (calendarField >= 0) {
910 // assert(calendarField < Calendar.FIELD_COUNT);
911 calendarToFieldMapping[calendarField] = this;
912 }
913 }
914 }
915
916 /**
917 * Returns the <code>Calendar</code> field associated with this
918 * attribute. For example, if this represents the hours field of
919 * a <code>Calendar</code>, this would return
920 * <code>Calendar.HOUR</code>. If there is no corresponding
921 * <code>Calendar</code> constant, this will return -1.
922 *
923 * @return Calendar constant for this field
924 * @see java.util.Calendar
925 */
926 public int getCalendarField() {
927 return calendarField;
928 }
929
930 /**
931 * Resolves instances being deserialized to the predefined constants.
932 *
933 * @throws InvalidObjectException if the constant could not be
934 * resolved.
935 * @return resolved DateFormat.Field constant
936 */
937 @Override
938 protected Object readResolve() throws InvalidObjectException {
939 if (this.getClass() != DateFormat.Field.class) {
940 throw new InvalidObjectException("subclass didn't correctly implement readResolve");
941 }
942
943 Object instance = instanceMap.get(getName());
944 if (instance != null) {
945 return instance;
946 } else {
947 throw new InvalidObjectException("unknown attribute name");
948 }
949 }
950
951 //
952 // The constants
953 //
954
955 /**
956 * Constant identifying the era field.
957 */
958 public static final Field ERA = new Field("era", Calendar.ERA);
959
960 /**
961 * Constant identifying the year field.
962 */
963 public static final Field YEAR = new Field("year", Calendar.YEAR);
964
965 /**
966 * Constant identifying the month field.
967 */
968 public static final Field MONTH = new Field("month", Calendar.MONTH);
969
970 /**
971 * Constant identifying the day of month field.
972 */
973 public static final Field DAY_OF_MONTH = new
974 Field("day of month", Calendar.DAY_OF_MONTH);
975
976 /**
977 * Constant identifying the hour of day field, where the legal values
978 * are 1 to 24.
979 */
980 public static final Field HOUR_OF_DAY1 = new Field("hour of day 1",-1);
981
982 /**
983 * Constant identifying the hour of day field, where the legal values
984 * are 0 to 23.
985 */
986 public static final Field HOUR_OF_DAY0 = new
987 Field("hour of day", Calendar.HOUR_OF_DAY);
988
989 /**
990 * Constant identifying the minute field.
991 */
992 public static final Field MINUTE =new Field("minute", Calendar.MINUTE);
993
994 /**
995 * Constant identifying the second field.
996 */
997 public static final Field SECOND =new Field("second", Calendar.SECOND);
998
999 /**
1000 * Constant identifying the millisecond field.
1001 */
1002 public static final Field MILLISECOND = new
1003 Field("millisecond", Calendar.MILLISECOND);
1004
1005 /**
1006 * Constant identifying the day of week field.
1007 */
1008 public static final Field DAY_OF_WEEK = new
1009 Field("day of week", Calendar.DAY_OF_WEEK);
1010
1011 /**
1012 * Constant identifying the day of year field.
1013 */
1014 public static final Field DAY_OF_YEAR = new
1015 Field("day of year", Calendar.DAY_OF_YEAR);
1016
1017 /**
1018 * Constant identifying the day of week field.
1019 */
1020 public static final Field DAY_OF_WEEK_IN_MONTH =
1021 new Field("day of week in month",
1022 Calendar.DAY_OF_WEEK_IN_MONTH);
1023
1024 /**
1025 * Constant identifying the week of year field.
1026 */
1027 public static final Field WEEK_OF_YEAR = new
1028 Field("week of year", Calendar.WEEK_OF_YEAR);
1029
1030 /**
1031 * Constant identifying the week of month field.
1032 */
1033 public static final Field WEEK_OF_MONTH = new
1034 Field("week of month", Calendar.WEEK_OF_MONTH);
1035
1036 /**
1037 * Constant identifying the time of day indicator
1038 * (e.g. "a.m." or "p.m.") field.
1039 */
1040 public static final Field AM_PM = new
1041 Field("am pm", Calendar.AM_PM);
1042
1043 /**
1044 * Constant identifying the hour field, where the legal values are
1045 * 1 to 12.
1046 */
1047 public static final Field HOUR1 = new Field("hour 1", -1);
1048
1049 /**
1050 * Constant identifying the hour field, where the legal values are
1051 * 0 to 11.
1052 */
1053 public static final Field HOUR0 = new
1054 Field("hour", Calendar.HOUR);
1055
1056 /**
1057 * Constant identifying the time zone field.
1058 */
1059 public static final Field TIME_ZONE = new Field("time zone", -1);
1060 }
1061 }