1 /*
2 * Copyright (c) 2012, 2013, 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 *
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24 */
25
26 /*
27 * This file is available under and governed by the GNU General Public
28 * License version 2 only, as published by the Free Software Foundation.
29 * However, the following notice accompanied the original version of this
30 * file:
31 *
32 * Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
33 *
34 * All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions are met:
38 *
39 * * Redistributions of source code must retain the above copyright notice,
40 * this list of conditions and the following disclaimer.
41 *
42 * * Redistributions in binary form must reproduce the above copyright notice,
43 * this list of conditions and the following disclaimer in the documentation
44 * and/or other materials provided with the distribution.
45 *
46 * * Neither the name of JSR-310 nor the names of its contributors
47 * may be used to endorse or promote products derived from this software
48 * without specific prior written permission.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
51 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
52 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
53 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
54 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
55 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
56 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
57 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
58 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
59 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
60 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61 */
62 package java.time;
63
64 import static java.time.temporal.ChronoField.DAY_OF_WEEK;
65 import static java.time.temporal.ChronoUnit.DAYS;
66
67 import java.time.format.DateTimeFormatterBuilder;
68 import java.time.format.TextStyle;
69 import java.time.temporal.ChronoField;
70 import java.time.temporal.Temporal;
71 import java.time.temporal.TemporalAccessor;
72 import java.time.temporal.TemporalAdjuster;
73 import java.time.temporal.TemporalField;
74 import java.time.temporal.TemporalQueries;
75 import java.time.temporal.TemporalQuery;
76 import java.time.temporal.UnsupportedTemporalTypeException;
77 import java.time.temporal.ValueRange;
78 import java.time.temporal.WeekFields;
79 import java.util.Locale;
80
81 /**
82 * A day-of-week, such as 'Tuesday'.
83 * <p>
84 * {@code DayOfWeek} is an enum representing the 7 days of the week -
85 * Monday, Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday.
86 * <p>
87 * In addition to the textual enum name, each day-of-week has an {@code int} value.
88 * The {@code int} value follows the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).
89 * It is recommended that applications use the enum rather than the {@code int} value
90 * to ensure code clarity.
91 * <p>
92 * This enum provides access to the localized textual form of the day-of-week.
93 * Some locales also assign different numeric values to the days, declaring
94 * Sunday to have the value 1, however this class provides no support for this.
95 * See {@link WeekFields} for localized week-numbering.
96 * <p>
97 * <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code DayOfWeek}.
98 * Use {@code getValue()} instead.</b>
99 * <p>
100 * This enum represents a common concept that is found in many calendar systems.
101 * As such, this enum may be used by any calendar system that has the day-of-week
102 * concept defined exactly equivalent to the ISO calendar system.
103 *
104 * @implSpec
105 * This is an immutable and thread-safe enum.
106 *
107 * @since 1.8
108 */
109 public enum DayOfWeek implements TemporalAccessor, TemporalAdjuster {
110
111 /**
112 * The singleton instance for the day-of-week of Monday.
113 * This has the numeric value of {@code 1}.
114 */
115 MONDAY,
116 /**
117 * The singleton instance for the day-of-week of Tuesday.
118 * This has the numeric value of {@code 2}.
119 */
120 TUESDAY,
121 /**
122 * The singleton instance for the day-of-week of Wednesday.
123 * This has the numeric value of {@code 3}.
124 */
125 WEDNESDAY,
126 /**
127 * The singleton instance for the day-of-week of Thursday.
128 * This has the numeric value of {@code 4}.
129 */
130 THURSDAY,
131 /**
132 * The singleton instance for the day-of-week of Friday.
133 * This has the numeric value of {@code 5}.
134 */
135 FRIDAY,
136 /**
137 * The singleton instance for the day-of-week of Saturday.
138 * This has the numeric value of {@code 6}.
139 */
140 SATURDAY,
141 /**
142 * The singleton instance for the day-of-week of Sunday.
143 * This has the numeric value of {@code 7}.
144 */
145 SUNDAY;
146 /**
147 * Private cache of all the constants.
148 */
149 private static final DayOfWeek[] ENUMS = DayOfWeek.values();
150
151 //-----------------------------------------------------------------------
152 /**
153 * Obtains an instance of {@code DayOfWeek} from an {@code int} value.
154 * <p>
155 * {@code DayOfWeek} is an enum representing the 7 days of the week.
156 * This factory allows the enum to be obtained from the {@code int} value.
157 * The {@code int} value follows the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).
158 *
159 * @param dayOfWeek the day-of-week to represent, from 1 (Monday) to 7 (Sunday)
160 * @return the day-of-week singleton, not null
161 * @throws DateTimeException if the day-of-week is invalid
162 */
163 public static DayOfWeek of(int dayOfWeek) {
164 if (dayOfWeek < 1 || dayOfWeek > 7) {
165 throw new DateTimeException("Invalid value for DayOfWeek: " + dayOfWeek);
166 }
167 return ENUMS[dayOfWeek - 1];
168 }
169
170 //-----------------------------------------------------------------------
171 /**
172 * Obtains an instance of {@code DayOfWeek} from a temporal object.
173 * <p>
174 * This obtains a day-of-week based on the specified temporal.
175 * A {@code TemporalAccessor} represents an arbitrary set of date and time information,
176 * which this factory converts to an instance of {@code DayOfWeek}.
177 * <p>
178 * The conversion extracts the {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} field.
179 * <p>
180 * This method matches the signature of the functional interface {@link TemporalQuery}
181 * allowing it to be used as a query via method reference, {@code DayOfWeek::from}.
182 *
183 * @param temporal the temporal object to convert, not null
184 * @return the day-of-week, not null
185 * @throws DateTimeException if unable to convert to a {@code DayOfWeek}
186 */
187 public static DayOfWeek from(TemporalAccessor temporal) {
188 if (temporal instanceof DayOfWeek) {
189 return (DayOfWeek) temporal;
190 }
191 try {
192 return of(temporal.get(DAY_OF_WEEK));
193 } catch (DateTimeException ex) {
194 throw new DateTimeException("Unable to obtain DayOfWeek from TemporalAccessor: " +
195 temporal + " of type " + temporal.getClass().getName(), ex);
196 }
197 }
198
199 //-----------------------------------------------------------------------
200 /**
201 * Gets the day-of-week {@code int} value.
202 * <p>
203 * The values are numbered following the ISO-8601 standard, from 1 (Monday) to 7 (Sunday).
204 * See {@link java.time.temporal.WeekFields#dayOfWeek()} for localized week-numbering.
205 *
206 * @return the day-of-week, from 1 (Monday) to 7 (Sunday)
207 */
208 public int getValue() {
209 return ordinal() + 1;
210 }
211
212 //-----------------------------------------------------------------------
213 /**
214 * Gets the textual representation, such as 'Mon' or 'Friday'.
215 * <p>
216 * This returns the textual name used to identify the day-of-week,
217 * suitable for presentation to the user.
218 * The parameters control the style of the returned text and the locale.
219 * <p>
220 * If no textual mapping is found then the {@link #getValue() numeric value} is returned.
221 *
222 * @param style the length of the text required, not null
223 * @param locale the locale to use, not null
224 * @return the text value of the day-of-week, not null
225 */
226 public String getDisplayName(TextStyle style, Locale locale) {
227 return new DateTimeFormatterBuilder().appendText(DAY_OF_WEEK, style).toFormatter(locale).format(this);
228 }
229
230 //-----------------------------------------------------------------------
231 /**
232 * Checks if the specified field is supported.
233 * <p>
234 * This checks if this day-of-week can be queried for the specified field.
235 * If false, then calling the {@link #range(TemporalField) range} and
236 * {@link #get(TemporalField) get} methods will throw an exception.
237 * <p>
238 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then
239 * this method returns true.
240 * All other {@code ChronoField} instances will return false.
241 * <p>
242 * If the field is not a {@code ChronoField}, then the result of this method
243 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
244 * passing {@code this} as the argument.
245 * Whether the field is supported is determined by the field.
246 *
247 * @param field the field to check, null returns false
248 * @return true if the field is supported on this day-of-week, false if not
249 */
250 @Override
251 public boolean isSupported(TemporalField field) {
252 if (field instanceof ChronoField) {
253 return field == DAY_OF_WEEK;
254 }
255 return field != null && field.isSupportedBy(this);
256 }
257
258 /**
259 * Gets the range of valid values for the specified field.
260 * <p>
261 * The range object expresses the minimum and maximum valid values for a field.
262 * This day-of-week is used to enhance the accuracy of the returned range.
263 * If it is not possible to return the range, because the field is not supported
264 * or for some other reason, an exception is thrown.
265 * <p>
266 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the
267 * range of the day-of-week, from 1 to 7, will be returned.
268 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
269 * <p>
270 * If the field is not a {@code ChronoField}, then the result of this method
271 * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
272 * passing {@code this} as the argument.
273 * Whether the range can be obtained is determined by the field.
274 *
275 * @param field the field to query the range for, not null
276 * @return the range of valid values for the field, not null
277 * @throws DateTimeException if the range for the field cannot be obtained
278 * @throws UnsupportedTemporalTypeException if the field is not supported
279 */
280 @Override
281 public ValueRange range(TemporalField field) {
282 if (field == DAY_OF_WEEK) {
283 return field.range();
284 }
285 return TemporalAccessor.super.range(field);
286 }
287
288 /**
289 * Gets the value of the specified field from this day-of-week as an {@code int}.
290 * <p>
291 * This queries this day-of-week for the value of the specified field.
292 * The returned value will always be within the valid range of values for the field.
293 * If it is not possible to return the value, because the field is not supported
294 * or for some other reason, an exception is thrown.
295 * <p>
296 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the
297 * value of the day-of-week, from 1 to 7, will be returned.
298 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
299 * <p>
300 * If the field is not a {@code ChronoField}, then the result of this method
301 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
302 * passing {@code this} as the argument. Whether the value can be obtained,
303 * and what the value represents, is determined by the field.
304 *
305 * @param field the field to get, not null
306 * @return the value for the field, within the valid range of values
307 * @throws DateTimeException if a value for the field cannot be obtained or
308 * the value is outside the range of valid values for the field
309 * @throws UnsupportedTemporalTypeException if the field is not supported or
310 * the range of values exceeds an {@code int}
311 * @throws ArithmeticException if numeric overflow occurs
312 */
313 @Override
314 public int get(TemporalField field) {
315 if (field == DAY_OF_WEEK) {
316 return getValue();
317 }
318 return TemporalAccessor.super.get(field);
319 }
320
321 /**
322 * Gets the value of the specified field from this day-of-week as a {@code long}.
323 * <p>
324 * This queries this day-of-week for the value of the specified field.
325 * If it is not possible to return the value, because the field is not supported
326 * or for some other reason, an exception is thrown.
327 * <p>
328 * If the field is {@link ChronoField#DAY_OF_WEEK DAY_OF_WEEK} then the
329 * value of the day-of-week, from 1 to 7, will be returned.
330 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
331 * <p>
332 * If the field is not a {@code ChronoField}, then the result of this method
333 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
334 * passing {@code this} as the argument. Whether the value can be obtained,
335 * and what the value represents, is determined by the field.
336 *
337 * @param field the field to get, not null
338 * @return the value for the field
339 * @throws DateTimeException if a value for the field cannot be obtained
340 * @throws UnsupportedTemporalTypeException if the field is not supported
341 * @throws ArithmeticException if numeric overflow occurs
342 */
343 @Override
344 public long getLong(TemporalField field) {
345 if (field == DAY_OF_WEEK) {
346 return getValue();
347 } else if (field instanceof ChronoField) {
348 throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
349 }
350 return field.getFrom(this);
351 }
352
353 //-----------------------------------------------------------------------
354 /**
355 * Returns the day-of-week that is the specified number of days after this one.
356 * <p>
357 * The calculation rolls around the end of the week from Sunday to Monday.
358 * The specified period may be negative.
359 * <p>
360 * This instance is immutable and unaffected by this method call.
361 *
362 * @param days the days to add, positive or negative
363 * @return the resulting day-of-week, not null
364 */
365 public DayOfWeek plus(long days) {
366 int amount = (int) (days % 7);
367 return ENUMS[(ordinal() + (amount + 7)) % 7];
368 }
369
370 /**
371 * Returns the day-of-week that is the specified number of days before this one.
372 * <p>
373 * The calculation rolls around the start of the year from Monday to Sunday.
374 * The specified period may be negative.
375 * <p>
376 * This instance is immutable and unaffected by this method call.
377 *
378 * @param days the days to subtract, positive or negative
379 * @return the resulting day-of-week, not null
380 */
381 public DayOfWeek minus(long days) {
382 return plus(-(days % 7));
383 }
384
385 //-----------------------------------------------------------------------
386 /**
387 * Queries this day-of-week using the specified query.
388 * <p>
389 * This queries this day-of-week using the specified query strategy object.
390 * The {@code TemporalQuery} object defines the logic to be used to
391 * obtain the result. Read the documentation of the query to understand
392 * what the result of this method will be.
393 * <p>
394 * The result of this method is obtained by invoking the
395 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
396 * specified query passing {@code this} as the argument.
397 *
398 * @param <R> the type of the result
399 * @param query the query to invoke, not null
400 * @return the query result, null may be returned (defined by the query)
401 * @throws DateTimeException if unable to query (defined by the query)
402 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
403 */
404 @SuppressWarnings("unchecked")
405 @Override
406 public <R> R query(TemporalQuery<R> query) {
407 if (query == TemporalQueries.precision()) {
408 return (R) DAYS;
409 }
410 return TemporalAccessor.super.query(query);
411 }
412
413 /**
414 * Adjusts the specified temporal object to have this day-of-week.
415 * <p>
416 * This returns a temporal object of the same observable type as the input
417 * with the day-of-week changed to be the same as this.
418 * <p>
419 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
420 * passing {@link ChronoField#DAY_OF_WEEK} as the field.
421 * Note that this adjusts forwards or backwards within a Monday to Sunday week.
422 * See {@link java.time.temporal.WeekFields#dayOfWeek()} for localized week start days.
423 * See {@code TemporalAdjuster} for other adjusters with more control,
424 * such as {@code next(MONDAY)}.
425 * <p>
426 * In most cases, it is clearer to reverse the calling pattern by using
427 * {@link Temporal#with(TemporalAdjuster)}:
428 * <pre>
429 * // these two lines are equivalent, but the second approach is recommended
430 * temporal = thisDayOfWeek.adjustInto(temporal);
431 * temporal = temporal.with(thisDayOfWeek);
432 * </pre>
433 * <p>
434 * For example, given a date that is a Wednesday, the following are output:
435 * <pre>
436 * dateOnWed.with(MONDAY); // two days earlier
437 * dateOnWed.with(TUESDAY); // one day earlier
438 * dateOnWed.with(WEDNESDAY); // same date
439 * dateOnWed.with(THURSDAY); // one day later
440 * dateOnWed.with(FRIDAY); // two days later
441 * dateOnWed.with(SATURDAY); // three days later
442 * dateOnWed.with(SUNDAY); // four days later
443 * </pre>
444 * <p>
445 * This instance is immutable and unaffected by this method call.
446 *
447 * @param temporal the target object to be adjusted, not null
448 * @return the adjusted object, not null
449 * @throws DateTimeException if unable to make the adjustment
450 * @throws ArithmeticException if numeric overflow occurs
451 */
452 @Override
453 public Temporal adjustInto(Temporal temporal) {
454 return temporal.with(DAY_OF_WEEK, getValue());
455 }
456
457 }
458