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1 : // © 2016 and later: Unicode, Inc. and others.
2 : // License & terms of use: http://www.unicode.org/copyright.html
3 : /*************************************************************************
4 : * Copyright (c) 1997-2016, International Business Machines Corporation
5 : * and others. All Rights Reserved.
6 : **************************************************************************
7 : *
8 : * File TIMEZONE.H
9 : *
10 : * Modification History:
11 : *
12 : * Date Name Description
13 : * 04/21/97 aliu Overhauled header.
14 : * 07/09/97 helena Changed createInstance to createDefault.
15 : * 08/06/97 aliu Removed dependency on internal header for Hashtable.
16 : * 08/10/98 stephen Changed getDisplayName() API conventions to match
17 : * 08/19/98 stephen Changed createTimeZone() to never return 0
18 : * 09/02/98 stephen Sync to JDK 1.2 8/31
19 : * - Added getOffset(... monthlen ...)
20 : * - Added hasSameRules()
21 : * 09/15/98 stephen Added getStaticClassID
22 : * 12/03/99 aliu Moved data out of static table into icudata.dll.
23 : * Hashtable replaced by new static data structures.
24 : * 12/14/99 aliu Made GMT public.
25 : * 08/15/01 grhoten Made GMT private and added the getGMT() function
26 : **************************************************************************
27 : */
28 :
29 : #ifndef TIMEZONE_H
30 : #define TIMEZONE_H
31 :
32 : #include "unicode/utypes.h"
33 :
34 : /**
35 : * \file
36 : * \brief C++ API: TimeZone object
37 : */
38 :
39 : #if !UCONFIG_NO_FORMATTING
40 :
41 : #include "unicode/uobject.h"
42 : #include "unicode/unistr.h"
43 : #include "unicode/ures.h"
44 : #include "unicode/ucal.h"
45 :
46 : U_NAMESPACE_BEGIN
47 :
48 : class StringEnumeration;
49 :
50 : /**
51 : *
52 : * <code>TimeZone</code> represents a time zone offset, and also figures out daylight
53 : * savings.
54 : *
55 : * <p>
56 : * Typically, you get a <code>TimeZone</code> using <code>createDefault</code>
57 : * which creates a <code>TimeZone</code> based on the time zone where the program
58 : * is running. For example, for a program running in Japan, <code>createDefault</code>
59 : * creates a <code>TimeZone</code> object based on Japanese Standard Time.
60 : *
61 : * <p>
62 : * You can also get a <code>TimeZone</code> using <code>createTimeZone</code> along
63 : * with a time zone ID. For instance, the time zone ID for the US Pacific
64 : * Time zone is "America/Los_Angeles". So, you can get a Pacific Time <code>TimeZone</code> object
65 : * with:
66 : * \htmlonly<blockquote>\endhtmlonly
67 : * <pre>
68 : * TimeZone *tz = TimeZone::createTimeZone("America/Los_Angeles");
69 : * </pre>
70 : * \htmlonly</blockquote>\endhtmlonly
71 : * You can use the <code>createEnumeration</code> method to iterate through
72 : * all the supported time zone IDs, or the <code>getCanonicalID</code> method to check
73 : * if a time zone ID is supported or not. You can then choose a
74 : * supported ID to get a <code>TimeZone</code>.
75 : * If the time zone you want is not represented by one of the
76 : * supported IDs, then you can create a custom time zone ID with
77 : * the following syntax:
78 : *
79 : * \htmlonly<blockquote>\endhtmlonly
80 : * <pre>
81 : * GMT[+|-]hh[[:]mm]
82 : * </pre>
83 : * \htmlonly</blockquote>\endhtmlonly
84 : *
85 : * For example, you might specify GMT+14:00 as a custom
86 : * time zone ID. The <code>TimeZone</code> that is returned
87 : * when you specify a custom time zone ID uses the specified
88 : * offset from GMT(=UTC) and does not observe daylight saving
89 : * time. For example, you might specify GMT+14:00 as a custom
90 : * time zone ID to create a TimeZone representing 14 hours ahead
91 : * of GMT (with no daylight saving time). In addition,
92 : * <code>getCanonicalID</code> can also be used to
93 : * normalize a custom time zone ID.
94 : *
95 : * TimeZone is an abstract class representing a time zone. A TimeZone is needed for
96 : * Calendar to produce local time for a particular time zone. A TimeZone comprises
97 : * three basic pieces of information:
98 : * <ul>
99 : * <li>A time zone offset; that, is the number of milliseconds to add or subtract
100 : * from a time expressed in terms of GMT to convert it to the same time in that
101 : * time zone (without taking daylight savings time into account).</li>
102 : * <li>Logic necessary to take daylight savings time into account if daylight savings
103 : * time is observed in that time zone (e.g., the days and hours on which daylight
104 : * savings time begins and ends).</li>
105 : * <li>An ID. This is a text string that uniquely identifies the time zone.</li>
106 : * </ul>
107 : *
108 : * (Only the ID is actually implemented in TimeZone; subclasses of TimeZone may handle
109 : * daylight savings time and GMT offset in different ways. Currently we have the following
110 : * TimeZone subclasses: RuleBasedTimeZone, SimpleTimeZone, and VTimeZone.)
111 : * <P>
112 : * The TimeZone class contains a static list containing a TimeZone object for every
113 : * combination of GMT offset and daylight-savings time rules currently in use in the
114 : * world, each with a unique ID. Each ID consists of a region (usually a continent or
115 : * ocean) and a city in that region, separated by a slash, (for example, US Pacific
116 : * Time is "America/Los_Angeles.") Because older versions of this class used
117 : * three- or four-letter abbreviations instead, there is also a table that maps the older
118 : * abbreviations to the newer ones (for example, "PST" maps to "America/Los_Angeles").
119 : * Anywhere the API requires an ID, you can use either form.
120 : * <P>
121 : * To create a new TimeZone, you call the factory function TimeZone::createTimeZone()
122 : * and pass it a time zone ID. You can use the createEnumeration() function to
123 : * obtain a list of all the time zone IDs recognized by createTimeZone().
124 : * <P>
125 : * You can also use TimeZone::createDefault() to create a TimeZone. This function uses
126 : * platform-specific APIs to produce a TimeZone for the time zone corresponding to
127 : * the client's computer's physical location. For example, if you're in Japan (assuming
128 : * your machine is set up correctly), TimeZone::createDefault() will return a TimeZone
129 : * for Japanese Standard Time ("Asia/Tokyo").
130 : */
131 : class U_I18N_API TimeZone : public UObject {
132 : public:
133 : /**
134 : * @stable ICU 2.0
135 : */
136 : virtual ~TimeZone();
137 :
138 : /**
139 : * Returns the "unknown" time zone.
140 : * It behaves like the GMT/UTC time zone but has the
141 : * <code>UCAL_UNKNOWN_ZONE_ID</code> = "Etc/Unknown".
142 : * createTimeZone() returns a mutable clone of this time zone if the input ID is not recognized.
143 : *
144 : * @return the "unknown" time zone.
145 : * @see UCAL_UNKNOWN_ZONE_ID
146 : * @see createTimeZone
147 : * @see getGMT
148 : * @stable ICU 49
149 : */
150 : static const TimeZone& U_EXPORT2 getUnknown();
151 :
152 : /**
153 : * The GMT (=UTC) time zone has a raw offset of zero and does not use daylight
154 : * savings time. This is a commonly used time zone.
155 : *
156 : * <p>Note: For backward compatibility reason, the ID used by the time
157 : * zone returned by this method is "GMT", although the ICU's canonical
158 : * ID for the GMT time zone is "Etc/GMT".
159 : *
160 : * @return the GMT/UTC time zone.
161 : * @see getUnknown
162 : * @stable ICU 2.0
163 : */
164 : static const TimeZone* U_EXPORT2 getGMT(void);
165 :
166 : /**
167 : * Creates a <code>TimeZone</code> for the given ID.
168 : * @param ID the ID for a <code>TimeZone</code>, such as "America/Los_Angeles",
169 : * or a custom ID such as "GMT-8:00".
170 : * @return the specified <code>TimeZone</code>, or a mutable clone of getUnknown()
171 : * if the given ID cannot be understood or if the given ID is "Etc/Unknown".
172 : * The return result is guaranteed to be non-NULL.
173 : * If you require that the specific zone asked for be returned,
174 : * compare the result with getUnknown() or check the ID of the return result.
175 : * @stable ICU 2.0
176 : */
177 : static TimeZone* U_EXPORT2 createTimeZone(const UnicodeString& ID);
178 :
179 : /**
180 : * Returns an enumeration over system time zone IDs with the given
181 : * filter conditions.
182 : * @param zoneType The system time zone type.
183 : * @param region The ISO 3166 two-letter country code or UN M.49
184 : * three-digit area code. When NULL, no filtering
185 : * done by region.
186 : * @param rawOffset An offset from GMT in milliseconds, ignoring
187 : * the effect of daylight savings time, if any.
188 : * When NULL, no filtering done by zone offset.
189 : * @param ec Output param to filled in with a success or
190 : * an error.
191 : * @return an enumeration object, owned by the caller.
192 : * @stable ICU 4.8
193 : */
194 : static StringEnumeration* U_EXPORT2 createTimeZoneIDEnumeration(
195 : USystemTimeZoneType zoneType,
196 : const char* region,
197 : const int32_t* rawOffset,
198 : UErrorCode& ec);
199 :
200 : /**
201 : * Returns an enumeration over all recognized time zone IDs. (i.e.,
202 : * all strings that createTimeZone() accepts)
203 : *
204 : * @return an enumeration object, owned by the caller.
205 : * @stable ICU 2.4
206 : */
207 : static StringEnumeration* U_EXPORT2 createEnumeration();
208 :
209 : /**
210 : * Returns an enumeration over time zone IDs with a given raw
211 : * offset from GMT. There may be several times zones with the
212 : * same GMT offset that differ in the way they handle daylight
213 : * savings time. For example, the state of Arizona doesn't
214 : * observe daylight savings time. If you ask for the time zone
215 : * IDs corresponding to GMT-7:00, you'll get back an enumeration
216 : * over two time zone IDs: "America/Denver," which corresponds to
217 : * Mountain Standard Time in the winter and Mountain Daylight Time
218 : * in the summer, and "America/Phoenix", which corresponds to
219 : * Mountain Standard Time year-round, even in the summer.
220 : *
221 : * @param rawOffset an offset from GMT in milliseconds, ignoring
222 : * the effect of daylight savings time, if any
223 : * @return an enumeration object, owned by the caller
224 : * @stable ICU 2.4
225 : */
226 : static StringEnumeration* U_EXPORT2 createEnumeration(int32_t rawOffset);
227 :
228 : /**
229 : * Returns an enumeration over time zone IDs associated with the
230 : * given country. Some zones are affiliated with no country
231 : * (e.g., "UTC"); these may also be retrieved, as a group.
232 : *
233 : * @param country The ISO 3166 two-letter country code, or NULL to
234 : * retrieve zones not affiliated with any country.
235 : * @return an enumeration object, owned by the caller
236 : * @stable ICU 2.4
237 : */
238 : static StringEnumeration* U_EXPORT2 createEnumeration(const char* country);
239 :
240 : /**
241 : * Returns the number of IDs in the equivalency group that
242 : * includes the given ID. An equivalency group contains zones
243 : * that have the same GMT offset and rules.
244 : *
245 : * <p>The returned count includes the given ID; it is always >= 1.
246 : * The given ID must be a system time zone. If it is not, returns
247 : * zero.
248 : * @param id a system time zone ID
249 : * @return the number of zones in the equivalency group containing
250 : * 'id', or zero if 'id' is not a valid system ID
251 : * @see #getEquivalentID
252 : * @stable ICU 2.0
253 : */
254 : static int32_t U_EXPORT2 countEquivalentIDs(const UnicodeString& id);
255 :
256 : /**
257 : * Returns an ID in the equivalency group that
258 : * includes the given ID. An equivalency group contains zones
259 : * that have the same GMT offset and rules.
260 : *
261 : * <p>The given index must be in the range 0..n-1, where n is the
262 : * value returned by <code>countEquivalentIDs(id)</code>. For
263 : * some value of 'index', the returned value will be equal to the
264 : * given id. If the given id is not a valid system time zone, or
265 : * if 'index' is out of range, then returns an empty string.
266 : * @param id a system time zone ID
267 : * @param index a value from 0 to n-1, where n is the value
268 : * returned by <code>countEquivalentIDs(id)</code>
269 : * @return the ID of the index-th zone in the equivalency group
270 : * containing 'id', or an empty string if 'id' is not a valid
271 : * system ID or 'index' is out of range
272 : * @see #countEquivalentIDs
273 : * @stable ICU 2.0
274 : */
275 : static const UnicodeString U_EXPORT2 getEquivalentID(const UnicodeString& id,
276 : int32_t index);
277 :
278 : /**
279 : * Creates an instance of TimeZone detected from the current host
280 : * system configuration. Note that ICU4C does not change the default
281 : * time zone unless TimeZone::adoptDefault(TimeZone*) or
282 : * TimeZone::setDefault(const TimeZone&) is explicitly called by a
283 : * user. This method does not update the current ICU's default,
284 : * and may return a different TimeZone from the one returned by
285 : * TimeZone::createDefault().
286 : *
287 : * @return A new instance of TimeZone detected from the current host system
288 : * configuration.
289 : * @stable ICU 55
290 : */
291 : static TimeZone* U_EXPORT2 detectHostTimeZone();
292 :
293 : /**
294 : * Creates a new copy of the default TimeZone for this host. Unless the default time
295 : * zone has already been set using adoptDefault() or setDefault(), the default is
296 : * determined by querying the system using methods in TPlatformUtilities. If the
297 : * system routines fail, or if they specify a TimeZone or TimeZone offset which is not
298 : * recognized, the TimeZone indicated by the ID kLastResortID is instantiated
299 : * and made the default.
300 : *
301 : * @return A default TimeZone. Clients are responsible for deleting the time zone
302 : * object returned.
303 : * @stable ICU 2.0
304 : */
305 : static TimeZone* U_EXPORT2 createDefault(void);
306 :
307 : #define ICU_TZ_HAS_RECREATE_DEFAULT
308 : static void U_EXPORT2 recreateDefault();
309 :
310 : /**
311 : * Sets the default time zone (i.e., what's returned by createDefault()) to be the
312 : * specified time zone. If NULL is specified for the time zone, the default time
313 : * zone is set to the default host time zone. This call adopts the TimeZone object
314 : * passed in; the client is no longer responsible for deleting it.
315 : *
316 : * <p>This function is not thread safe. It is an error for multiple threads
317 : * to concurrently attempt to set the default time zone, or for any thread
318 : * to attempt to reference the default zone while another thread is setting it.
319 : *
320 : * @param zone A pointer to the new TimeZone object to use as the default.
321 : * @stable ICU 2.0
322 : */
323 : static void U_EXPORT2 adoptDefault(TimeZone* zone);
324 :
325 : #ifndef U_HIDE_SYSTEM_API
326 : /**
327 : * Same as adoptDefault(), except that the TimeZone object passed in is NOT adopted;
328 : * the caller remains responsible for deleting it.
329 : *
330 : * <p>See the thread safety note under adoptDefault().
331 : *
332 : * @param zone The given timezone.
333 : * @system
334 : * @stable ICU 2.0
335 : */
336 : static void U_EXPORT2 setDefault(const TimeZone& zone);
337 : #endif /* U_HIDE_SYSTEM_API */
338 :
339 : /**
340 : * Returns the timezone data version currently used by ICU.
341 : * @param status Output param to filled in with a success or an error.
342 : * @return the version string, such as "2007f"
343 : * @stable ICU 3.8
344 : */
345 : static const char* U_EXPORT2 getTZDataVersion(UErrorCode& status);
346 :
347 : /**
348 : * Returns the canonical system timezone ID or the normalized
349 : * custom time zone ID for the given time zone ID.
350 : * @param id The input time zone ID to be canonicalized.
351 : * @param canonicalID Receives the canonical system time zone ID
352 : * or the custom time zone ID in normalized format.
353 : * @param status Receives the status. When the given time zone ID
354 : * is neither a known system time zone ID nor a
355 : * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR
356 : * is set.
357 : * @return A reference to the result.
358 : * @stable ICU 4.0
359 : */
360 : static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id,
361 : UnicodeString& canonicalID, UErrorCode& status);
362 :
363 : /**
364 : * Returns the canonical system time zone ID or the normalized
365 : * custom time zone ID for the given time zone ID.
366 : * @param id The input time zone ID to be canonicalized.
367 : * @param canonicalID Receives the canonical system time zone ID
368 : * or the custom time zone ID in normalized format.
369 : * @param isSystemID Receives if the given ID is a known system
370 : * time zone ID.
371 : * @param status Receives the status. When the given time zone ID
372 : * is neither a known system time zone ID nor a
373 : * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR
374 : * is set.
375 : * @return A reference to the result.
376 : * @stable ICU 4.0
377 : */
378 : static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id,
379 : UnicodeString& canonicalID, UBool& isSystemID, UErrorCode& status);
380 :
381 : /**
382 : * Converts a system time zone ID to an equivalent Windows time zone ID. For example,
383 : * Windows time zone ID "Pacific Standard Time" is returned for input "America/Los_Angeles".
384 : *
385 : * <p>There are system time zones that cannot be mapped to Windows zones. When the input
386 : * system time zone ID is unknown or unmappable to a Windows time zone, then the result will be
387 : * empty, but the operation itself remains successful (no error status set on return).
388 : *
389 : * <p>This implementation utilizes <a href="http://unicode.org/cldr/charts/supplemental/zone_tzid.html">
390 : * Zone-Tzid mapping data</a>. The mapping data is updated time to time. To get the latest changes,
391 : * please read the ICU user guide section <a href="http://userguide.icu-project.org/datetime/timezone#TOC-Updating-the-Time-Zone-Data">
392 : * Updating the Time Zone Data</a>.
393 : *
394 : * @param id A system time zone ID.
395 : * @param winid Receives a Windows time zone ID. When the input system time zone ID is unknown
396 : * or unmappable to a Windows time zone ID, then an empty string is set on return.
397 : * @param status Receives the status.
398 : * @return A reference to the result (<code>winid</code>).
399 : * @see getIDForWindowsID
400 : *
401 : * @stable ICU 52
402 : */
403 : static UnicodeString& U_EXPORT2 getWindowsID(const UnicodeString& id,
404 : UnicodeString& winid, UErrorCode& status);
405 :
406 : /**
407 : * Converts a Windows time zone ID to an equivalent system time zone ID
408 : * for a region. For example, system time zone ID "America/Los_Angeles" is returned
409 : * for input Windows ID "Pacific Standard Time" and region "US" (or <code>null</code>),
410 : * "America/Vancouver" is returned for the same Windows ID "Pacific Standard Time" and
411 : * region "CA".
412 : *
413 : * <p>Not all Windows time zones can be mapped to system time zones. When the input
414 : * Windows time zone ID is unknown or unmappable to a system time zone, then the result
415 : * will be empty, but the operation itself remains successful (no error status set on return).
416 : *
417 : * <p>This implementation utilizes <a href="http://unicode.org/cldr/charts/supplemental/zone_tzid.html">
418 : * Zone-Tzid mapping data</a>. The mapping data is updated time to time. To get the latest changes,
419 : * please read the ICU user guide section <a href="http://userguide.icu-project.org/datetime/timezone#TOC-Updating-the-Time-Zone-Data">
420 : * Updating the Time Zone Data</a>.
421 : *
422 : * @param winid A Windows time zone ID.
423 : * @param region A null-terminated region code, or <code>NULL</code> if no regional preference.
424 : * @param id Receives a system time zone ID. When the input Windows time zone ID is unknown
425 : * or unmappable to a system time zone ID, then an empty string is set on return.
426 : * @param status Receives the status.
427 : * @return A reference to the result (<code>id</code>).
428 : * @see getWindowsID
429 : *
430 : * @stable ICU 52
431 : */
432 : static UnicodeString& U_EXPORT2 getIDForWindowsID(const UnicodeString& winid, const char* region,
433 : UnicodeString& id, UErrorCode& status);
434 :
435 : /**
436 : * Returns true if the two TimeZones are equal. (The TimeZone version only compares
437 : * IDs, but subclasses are expected to also compare the fields they add.)
438 : *
439 : * @param that The TimeZone object to be compared with.
440 : * @return True if the given TimeZone is equal to this TimeZone; false
441 : * otherwise.
442 : * @stable ICU 2.0
443 : */
444 : virtual UBool operator==(const TimeZone& that) const;
445 :
446 : /**
447 : * Returns true if the two TimeZones are NOT equal; that is, if operator==() returns
448 : * false.
449 : *
450 : * @param that The TimeZone object to be compared with.
451 : * @return True if the given TimeZone is not equal to this TimeZone; false
452 : * otherwise.
453 : * @stable ICU 2.0
454 : */
455 0 : UBool operator!=(const TimeZone& that) const {return !operator==(that);}
456 :
457 : /**
458 : * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add
459 : * to GMT to get local time in this time zone, taking daylight savings time into
460 : * account) as of a particular reference date. The reference date is used to determine
461 : * whether daylight savings time is in effect and needs to be figured into the offset
462 : * that is returned (in other words, what is the adjusted GMT offset in this time zone
463 : * at this particular date and time?). For the time zones produced by createTimeZone(),
464 : * the reference data is specified according to the Gregorian calendar, and the date
465 : * and time fields are local standard time.
466 : *
467 : * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
468 : * which returns both the raw and the DST offset for a given time. This method
469 : * is retained only for backward compatibility.
470 : *
471 : * @param era The reference date's era
472 : * @param year The reference date's year
473 : * @param month The reference date's month (0-based; 0 is January)
474 : * @param day The reference date's day-in-month (1-based)
475 : * @param dayOfWeek The reference date's day-of-week (1-based; 1 is Sunday)
476 : * @param millis The reference date's milliseconds in day, local standard time
477 : * @param status Output param to filled in with a success or an error.
478 : * @return The offset in milliseconds to add to GMT to get local time.
479 : * @stable ICU 2.0
480 : */
481 : virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
482 : uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const = 0;
483 :
484 : /**
485 : * Gets the time zone offset, for current date, modified in case of
486 : * daylight savings. This is the offset to add *to* UTC to get local time.
487 : *
488 : * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
489 : * which returns both the raw and the DST offset for a given time. This method
490 : * is retained only for backward compatibility.
491 : *
492 : * @param era the era of the given date.
493 : * @param year the year in the given date.
494 : * @param month the month in the given date.
495 : * Month is 0-based. e.g., 0 for January.
496 : * @param day the day-in-month of the given date.
497 : * @param dayOfWeek the day-of-week of the given date.
498 : * @param milliseconds the millis in day in <em>standard</em> local time.
499 : * @param monthLength the length of the given month in days.
500 : * @param status Output param to filled in with a success or an error.
501 : * @return the offset to add *to* GMT to get local time.
502 : * @stable ICU 2.0
503 : */
504 : virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
505 : uint8_t dayOfWeek, int32_t milliseconds,
506 : int32_t monthLength, UErrorCode& status) const = 0;
507 :
508 : /**
509 : * Returns the time zone raw and GMT offset for the given moment
510 : * in time. Upon return, local-millis = GMT-millis + rawOffset +
511 : * dstOffset. All computations are performed in the proleptic
512 : * Gregorian calendar. The default implementation in the TimeZone
513 : * class delegates to the 8-argument getOffset().
514 : *
515 : * @param date moment in time for which to return offsets, in
516 : * units of milliseconds from January 1, 1970 0:00 GMT, either GMT
517 : * time or local wall time, depending on `local'.
518 : * @param local if true, `date' is local wall time; otherwise it
519 : * is in GMT time.
520 : * @param rawOffset output parameter to receive the raw offset, that
521 : * is, the offset not including DST adjustments
522 : * @param dstOffset output parameter to receive the DST offset,
523 : * that is, the offset to be added to `rawOffset' to obtain the
524 : * total offset between local and GMT time. If DST is not in
525 : * effect, this value is zero; otherwise it is a positive value,
526 : * typically one hour.
527 : * @param ec input-output error code
528 : *
529 : * @stable ICU 2.8
530 : */
531 : virtual void getOffset(UDate date, UBool local, int32_t& rawOffset,
532 : int32_t& dstOffset, UErrorCode& ec) const;
533 :
534 : /**
535 : * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
536 : * to GMT to get local time, before taking daylight savings time into account).
537 : *
538 : * @param offsetMillis The new raw GMT offset for this time zone.
539 : * @stable ICU 2.0
540 : */
541 : virtual void setRawOffset(int32_t offsetMillis) = 0;
542 :
543 : /**
544 : * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
545 : * to GMT to get local time, before taking daylight savings time into account).
546 : *
547 : * @return The TimeZone's raw GMT offset.
548 : * @stable ICU 2.0
549 : */
550 : virtual int32_t getRawOffset(void) const = 0;
551 :
552 : /**
553 : * Fills in "ID" with the TimeZone's ID.
554 : *
555 : * @param ID Receives this TimeZone's ID.
556 : * @return A reference to 'ID'
557 : * @stable ICU 2.0
558 : */
559 : UnicodeString& getID(UnicodeString& ID) const;
560 :
561 : /**
562 : * Sets the TimeZone's ID to the specified value. This doesn't affect any other
563 : * fields (for example, if you say<
564 : * blockquote><pre>
565 : * . TimeZone* foo = TimeZone::createTimeZone("America/New_York");
566 : * . foo.setID("America/Los_Angeles");
567 : * </pre>\htmlonly</blockquote>\endhtmlonly
568 : * the time zone's GMT offset and daylight-savings rules don't change to those for
569 : * Los Angeles. They're still those for New York. Only the ID has changed.)
570 : *
571 : * @param ID The new time zone ID.
572 : * @stable ICU 2.0
573 : */
574 : void setID(const UnicodeString& ID);
575 :
576 : /**
577 : * Enum for use with getDisplayName
578 : * @stable ICU 2.4
579 : */
580 : enum EDisplayType {
581 : /**
582 : * Selector for short display name
583 : * @stable ICU 2.4
584 : */
585 : SHORT = 1,
586 : /**
587 : * Selector for long display name
588 : * @stable ICU 2.4
589 : */
590 : LONG,
591 : /**
592 : * Selector for short generic display name
593 : * @stable ICU 4.4
594 : */
595 : SHORT_GENERIC,
596 : /**
597 : * Selector for long generic display name
598 : * @stable ICU 4.4
599 : */
600 : LONG_GENERIC,
601 : /**
602 : * Selector for short display name derived
603 : * from time zone offset
604 : * @stable ICU 4.4
605 : */
606 : SHORT_GMT,
607 : /**
608 : * Selector for long display name derived
609 : * from time zone offset
610 : * @stable ICU 4.4
611 : */
612 : LONG_GMT,
613 : /**
614 : * Selector for short display name derived
615 : * from the time zone's fallback name
616 : * @stable ICU 4.4
617 : */
618 : SHORT_COMMONLY_USED,
619 : /**
620 : * Selector for long display name derived
621 : * from the time zone's fallback name
622 : * @stable ICU 4.4
623 : */
624 : GENERIC_LOCATION
625 : };
626 :
627 : /**
628 : * Returns a name of this time zone suitable for presentation to the user
629 : * in the default locale.
630 : * This method returns the long name, not including daylight savings.
631 : * If the display name is not available for the locale,
632 : * then this method returns a string in the localized GMT offset format
633 : * such as <code>GMT[+-]HH:mm</code>.
634 : * @param result the human-readable name of this time zone in the default locale.
635 : * @return A reference to 'result'.
636 : * @stable ICU 2.0
637 : */
638 : UnicodeString& getDisplayName(UnicodeString& result) const;
639 :
640 : /**
641 : * Returns a name of this time zone suitable for presentation to the user
642 : * in the specified locale.
643 : * This method returns the long name, not including daylight savings.
644 : * If the display name is not available for the locale,
645 : * then this method returns a string in the localized GMT offset format
646 : * such as <code>GMT[+-]HH:mm</code>.
647 : * @param locale the locale in which to supply the display name.
648 : * @param result the human-readable name of this time zone in the given locale
649 : * or in the default locale if the given locale is not recognized.
650 : * @return A reference to 'result'.
651 : * @stable ICU 2.0
652 : */
653 : UnicodeString& getDisplayName(const Locale& locale, UnicodeString& result) const;
654 :
655 : /**
656 : * Returns a name of this time zone suitable for presentation to the user
657 : * in the default locale.
658 : * If the display name is not available for the locale,
659 : * then this method returns a string in the localized GMT offset format
660 : * such as <code>GMT[+-]HH:mm</code>.
661 : * @param daylight if true, return the daylight savings name.
662 : * @param style
663 : * @param result the human-readable name of this time zone in the default locale.
664 : * @return A reference to 'result'.
665 : * @stable ICU 2.0
666 : */
667 : UnicodeString& getDisplayName(UBool daylight, EDisplayType style, UnicodeString& result) const;
668 :
669 : /**
670 : * Returns a name of this time zone suitable for presentation to the user
671 : * in the specified locale.
672 : * If the display name is not available for the locale,
673 : * then this method returns a string in the localized GMT offset format
674 : * such as <code>GMT[+-]HH:mm</code>.
675 : * @param daylight if true, return the daylight savings name.
676 : * @param style
677 : * @param locale the locale in which to supply the display name.
678 : * @param result the human-readable name of this time zone in the given locale
679 : * or in the default locale if the given locale is not recognized.
680 : * @return A refence to 'result'.
681 : * @stable ICU 2.0
682 : */
683 : UnicodeString& getDisplayName(UBool daylight, EDisplayType style, const Locale& locale, UnicodeString& result) const;
684 :
685 : /**
686 : * Queries if this time zone uses daylight savings time.
687 : * @return true if this time zone uses daylight savings time,
688 : * false, otherwise.
689 : * <p><strong>Note:</strong>The default implementation of
690 : * ICU TimeZone uses the tz database, which supports historic
691 : * rule changes, for system time zones. With the implementation,
692 : * there are time zones that used daylight savings time in the
693 : * past, but no longer used currently. For example, Asia/Tokyo has
694 : * never used daylight savings time since 1951. Most clients would
695 : * expect that this method to return <code>FALSE</code> for such case.
696 : * The default implementation of this method returns <code>TRUE</code>
697 : * when the time zone uses daylight savings time in the current
698 : * (Gregorian) calendar year.
699 : * <p>In Java 7, <code>observesDaylightTime()</code> was added in
700 : * addition to <code>useDaylightTime()</code>. In Java, <code>useDaylightTime()</code>
701 : * only checks if daylight saving time is observed by the last known
702 : * rule. This specification might not be what most users would expect
703 : * if daylight saving time is currently observed, but not scheduled
704 : * in future. In this case, Java's <code>userDaylightTime()</code> returns
705 : * <code>false</code>. To resolve the issue, Java 7 added <code>observesDaylightTime()</code>,
706 : * which takes the current rule into account. The method <code>observesDaylightTime()</code>
707 : * was added in ICU4J for supporting API signature compatibility with JDK.
708 : * In general, ICU4C also provides JDK compatible methods, but the current
709 : * implementation <code>userDaylightTime()</code> serves the purpose
710 : * (takes the current rule into account), <code>observesDaylightTime()</code>
711 : * is not added in ICU4C. In addition to <code>useDaylightTime()</code>, ICU4C
712 : * <code>BasicTimeZone</code> class (Note that <code>TimeZone::createTimeZone(const UnicodeString &ID)</code>
713 : * always returns a <code>BasicTimeZone</code>) provides a series of methods allowing
714 : * historic and future time zone rule iteration, so you can check if daylight saving
715 : * time is observed or not within a given period.
716 : *
717 : * @stable ICU 2.0
718 : */
719 : virtual UBool useDaylightTime(void) const = 0;
720 :
721 : /**
722 : * Queries if the given date is in daylight savings time in
723 : * this time zone.
724 : * This method is wasteful since it creates a new GregorianCalendar and
725 : * deletes it each time it is called. This is a deprecated method
726 : * and provided only for Java compatibility.
727 : *
728 : * @param date the given UDate.
729 : * @param status Output param filled in with success/error code.
730 : * @return true if the given date is in daylight savings time,
731 : * false, otherwise.
732 : * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead.
733 : */
734 : virtual UBool inDaylightTime(UDate date, UErrorCode& status) const = 0;
735 :
736 : /**
737 : * Returns true if this zone has the same rule and offset as another zone.
738 : * That is, if this zone differs only in ID, if at all.
739 : * @param other the <code>TimeZone</code> object to be compared with
740 : * @return true if the given zone is the same as this one,
741 : * with the possible exception of the ID
742 : * @stable ICU 2.0
743 : */
744 : virtual UBool hasSameRules(const TimeZone& other) const;
745 :
746 : /**
747 : * Clones TimeZone objects polymorphically. Clients are responsible for deleting
748 : * the TimeZone object cloned.
749 : *
750 : * @return A new copy of this TimeZone object.
751 : * @stable ICU 2.0
752 : */
753 : virtual TimeZone* clone(void) const = 0;
754 :
755 : /**
756 : * Return the class ID for this class. This is useful only for
757 : * comparing to a return value from getDynamicClassID().
758 : * @return The class ID for all objects of this class.
759 : * @stable ICU 2.0
760 : */
761 : static UClassID U_EXPORT2 getStaticClassID(void);
762 :
763 : /**
764 : * Returns a unique class ID POLYMORPHICALLY. This method is to
765 : * implement a simple version of RTTI, since not all C++ compilers support genuine
766 : * RTTI. Polymorphic operator==() and clone() methods call this method.
767 : * <P>
768 : * Concrete subclasses of TimeZone must use the UOBJECT_DEFINE_RTTI_IMPLEMENTATION
769 : * macro from uobject.h in their implementation to provide correct RTTI information.
770 : * @return The class ID for this object. All objects of a given class have the
771 : * same class ID. Objects of other classes have different class IDs.
772 : * @stable ICU 2.0
773 : */
774 : virtual UClassID getDynamicClassID(void) const = 0;
775 :
776 : /**
777 : * Returns the amount of time to be added to local standard time
778 : * to get local wall clock time.
779 : * <p>
780 : * The default implementation always returns 3600000 milliseconds
781 : * (i.e., one hour) if this time zone observes Daylight Saving
782 : * Time. Otherwise, 0 (zero) is returned.
783 : * <p>
784 : * If an underlying TimeZone implementation subclass supports
785 : * historical Daylight Saving Time changes, this method returns
786 : * the known latest daylight saving value.
787 : *
788 : * @return the amount of saving time in milliseconds
789 : * @stable ICU 3.6
790 : */
791 : virtual int32_t getDSTSavings() const;
792 :
793 : /**
794 : * Gets the region code associated with the given
795 : * system time zone ID. The region code is either ISO 3166
796 : * 2-letter country code or UN M.49 3-digit area code.
797 : * When the time zone is not associated with a specific location,
798 : * for example - "Etc/UTC", "EST5EDT", then this method returns
799 : * "001" (UN M.49 area code for World).
800 : *
801 : * @param id The system time zone ID.
802 : * @param region Output buffer for receiving the region code.
803 : * @param capacity The size of the output buffer.
804 : * @param status Receives the status. When the given time zone ID
805 : * is not a known system time zone ID,
806 : * U_ILLEGAL_ARGUMENT_ERROR is set.
807 : * @return The length of the output region code.
808 : * @stable ICU 4.8
809 : */
810 : static int32_t U_EXPORT2 getRegion(const UnicodeString& id,
811 : char *region, int32_t capacity, UErrorCode& status);
812 :
813 : protected:
814 :
815 : /**
816 : * Default constructor. ID is initialized to the empty string.
817 : * @stable ICU 2.0
818 : */
819 : TimeZone();
820 :
821 : /**
822 : * Construct a TimeZone with a given ID.
823 : * @param id a system time zone ID
824 : * @stable ICU 2.0
825 : */
826 : TimeZone(const UnicodeString &id);
827 :
828 : /**
829 : * Copy constructor.
830 : * @param source the object to be copied.
831 : * @stable ICU 2.0
832 : */
833 : TimeZone(const TimeZone& source);
834 :
835 : /**
836 : * Default assignment operator.
837 : * @param right the object to be copied.
838 : * @stable ICU 2.0
839 : */
840 : TimeZone& operator=(const TimeZone& right);
841 :
842 : #ifndef U_HIDE_INTERNAL_API
843 : /**
844 : * Utility function. For internally loading rule data.
845 : * @param top Top resource bundle for tz data
846 : * @param ruleid ID of rule to load
847 : * @param oldbundle Old bundle to reuse or NULL
848 : * @param status Status parameter
849 : * @return either a new bundle or *oldbundle
850 : * @internal
851 : */
852 : static UResourceBundle* loadRule(const UResourceBundle* top, const UnicodeString& ruleid, UResourceBundle* oldbundle, UErrorCode&status);
853 : #endif /* U_HIDE_INTERNAL_API */
854 :
855 : private:
856 : friend class ZoneMeta;
857 :
858 :
859 : static TimeZone* createCustomTimeZone(const UnicodeString&); // Creates a time zone based on the string.
860 :
861 : /**
862 : * Finds the given ID in the Olson tzdata. If the given ID is found in the tzdata,
863 : * returns the pointer to the ID resource. This method is exposed through ZoneMeta class
864 : * for ICU internal implementation and useful for building hashtable using a time zone
865 : * ID as a key.
866 : * @param id zone id string
867 : * @return the pointer of the ID resource, or NULL.
868 : */
869 : static const char16_t* findID(const UnicodeString& id);
870 :
871 : /**
872 : * Resolve a link in Olson tzdata. When the given id is known and it's not a link,
873 : * the id itself is returned. When the given id is known and it is a link, then
874 : * dereferenced zone id is returned. When the given id is unknown, then it returns
875 : * NULL.
876 : * @param id zone id string
877 : * @return the dereferenced zone or NULL
878 : */
879 : static const char16_t* dereferOlsonLink(const UnicodeString& id);
880 :
881 : /**
882 : * Returns the region code associated with the given zone,
883 : * or NULL if the zone is not known.
884 : * @param id zone id string
885 : * @return the region associated with the given zone
886 : */
887 : static const char16_t* getRegion(const UnicodeString& id);
888 :
889 : public:
890 : #ifndef U_HIDE_INTERNAL_API
891 : /**
892 : * Returns the region code associated with the given zone,
893 : * or NULL if the zone is not known.
894 : * @param id zone id string
895 : * @param status Status parameter
896 : * @return the region associated with the given zone
897 : * @internal
898 : */
899 : static const char16_t* getRegion(const UnicodeString& id, UErrorCode& status);
900 : #endif /* U_HIDE_INTERNAL_API */
901 :
902 : private:
903 : /**
904 : * Parses the given custom time zone identifier
905 : * @param id id A string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or
906 : * GMT[+-]hh.
907 : * @param sign Receves parsed sign, 1 for positive, -1 for negative.
908 : * @param hour Receives parsed hour field
909 : * @param minute Receives parsed minute field
910 : * @param second Receives parsed second field
911 : * @return Returns TRUE when the given custom id is valid.
912 : */
913 : static UBool parseCustomID(const UnicodeString& id, int32_t& sign, int32_t& hour,
914 : int32_t& minute, int32_t& second);
915 :
916 : /**
917 : * Parse a custom time zone identifier and return the normalized
918 : * custom time zone identifier for the given custom id string.
919 : * @param id a string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or
920 : * GMT[+-]hh.
921 : * @param normalized Receives the normalized custom ID
922 : * @param status Receives the status. When the input ID string is invalid,
923 : * U_ILLEGAL_ARGUMENT_ERROR is set.
924 : * @return The normalized custom id string.
925 : */
926 : static UnicodeString& getCustomID(const UnicodeString& id, UnicodeString& normalized,
927 : UErrorCode& status);
928 :
929 : /**
930 : * Returns the normalized custome time zone ID for the given offset fields.
931 : * @param hour offset hours
932 : * @param min offset minutes
933 : * @param sec offset seconds
934 : * @param negative sign of the offset, TRUE for negative offset.
935 : * @param id Receves the format result (normalized custom ID)
936 : * @return The reference to id
937 : */
938 : static UnicodeString& formatCustomID(int32_t hour, int32_t min, int32_t sec,
939 : UBool negative, UnicodeString& id);
940 :
941 : UnicodeString fID; // this time zone's ID
942 :
943 : friend class TZEnumeration;
944 : };
945 :
946 :
947 : // -------------------------------------
948 :
949 : inline UnicodeString&
950 0 : TimeZone::getID(UnicodeString& ID) const
951 : {
952 0 : ID = fID;
953 0 : return ID;
954 : }
955 :
956 : // -------------------------------------
957 :
958 : inline void
959 0 : TimeZone::setID(const UnicodeString& ID)
960 : {
961 0 : fID = ID;
962 0 : }
963 : U_NAMESPACE_END
964 :
965 : #endif /* #if !UCONFIG_NO_FORMATTING */
966 :
967 : #endif //_TIMEZONE
968 : //eof
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