1 /************************************************************************* 2 * Copyright (c) 1997-2014, International Business Machines Corporation 3 * and others. All Rights Reserved. 4 ************************************************************************** 5 * 6 * File TIMEZONE.H 7 * 8 * Modification History: 9 * 10 * Date Name Description 11 * 04/21/97 aliu Overhauled header. 12 * 07/09/97 helena Changed createInstance to createDefault. 13 * 08/06/97 aliu Removed dependency on internal header for Hashtable. 14 * 08/10/98 stephen Changed getDisplayName() API conventions to match 15 * 08/19/98 stephen Changed createTimeZone() to never return 0 16 * 09/02/98 stephen Sync to JDK 1.2 8/31 17 * - Added getOffset(... monthlen ...) 18 * - Added hasSameRules() 19 * 09/15/98 stephen Added getStaticClassID 20 * 12/03/99 aliu Moved data out of static table into icudata.dll. 21 * Hashtable replaced by new static data structures. 22 * 12/14/99 aliu Made GMT public. 23 * 08/15/01 grhoten Made GMT private and added the getGMT() function 24 ************************************************************************** 25 */ 26 27 #ifndef TIMEZONE_H 28 #define TIMEZONE_H 29 30 #include "unicode/utypes.h" 31 32 /** 33 * \file 34 * \brief C++ API: TimeZone object 35 */ 36 37 #if !UCONFIG_NO_FORMATTING 38 39 #include "unicode/uobject.h" 40 #include "unicode/unistr.h" 41 #include "unicode/ures.h" 42 #include "unicode/ucal.h" 43 44 U_NAMESPACE_BEGIN 45 46 class StringEnumeration; 47 48 /** 49 * 50 * <code>TimeZone</code> represents a time zone offset, and also figures out daylight 51 * savings. 52 * 53 * <p> 54 * Typically, you get a <code>TimeZone</code> using <code>createDefault</code> 55 * which creates a <code>TimeZone</code> based on the time zone where the program 56 * is running. For example, for a program running in Japan, <code>createDefault</code> 57 * creates a <code>TimeZone</code> object based on Japanese Standard Time. 58 * 59 * <p> 60 * You can also get a <code>TimeZone</code> using <code>createTimeZone</code> along 61 * with a time zone ID. For instance, the time zone ID for the US Pacific 62 * Time zone is "America/Los_Angeles". So, you can get a Pacific Time <code>TimeZone</code> object 63 * with: 64 * \htmlonly<blockquote>\endhtmlonly 65 * <pre> 66 * TimeZone *tz = TimeZone::createTimeZone("America/Los_Angeles"); 67 * </pre> 68 * \htmlonly</blockquote>\endhtmlonly 69 * You can use <code>getAvailableIDs</code> method to iterate through 70 * all the supported time zone IDs, or getCanonicalID method to check 71 * if a time zone ID is supported or not. You can then choose a 72 * supported ID to get a <code>TimeZone</code>. 73 * If the time zone you want is not represented by one of the 74 * supported IDs, then you can create a custom time zone ID with 75 * the following syntax: 76 * 77 * \htmlonly<blockquote>\endhtmlonly 78 * <pre> 79 * GMT[+|-]hh[[:]mm] 80 * </pre> 81 * \htmlonly</blockquote>\endhtmlonly 82 * 83 * For example, you might specify GMT+14:00 as a custom 84 * time zone ID. The <code>TimeZone</code> that is returned 85 * when you specify a custom time zone ID uses the specified 86 * offset from GMT(=UTC) and does not observe daylight saving 87 * time. For example, you might specify GMT+14:00 as a custom 88 * time zone ID to create a TimeZone representing 14 hours ahead 89 * of GMT (with no daylight saving time). In addition, 90 * <code>getCanonicalID</code> can also be used to 91 * normalize a custom time zone ID. 92 * 93 * TimeZone is an abstract class representing a time zone. A TimeZone is needed for 94 * Calendar to produce local time for a particular time zone. A TimeZone comprises 95 * three basic pieces of information: 96 * <ul> 97 * <li>A time zone offset; that, is the number of milliseconds to add or subtract 98 * from a time expressed in terms of GMT to convert it to the same time in that 99 * time zone (without taking daylight savings time into account).</li> 100 * <li>Logic necessary to take daylight savings time into account if daylight savings 101 * time is observed in that time zone (e.g., the days and hours on which daylight 102 * savings time begins and ends).</li> 103 * <li>An ID. This is a text string that uniquely identifies the time zone.</li> 104 * </ul> 105 * 106 * (Only the ID is actually implemented in TimeZone; subclasses of TimeZone may handle 107 * daylight savings time and GMT offset in different ways. Currently we have the following 108 * TimeZone subclasses: RuleBasedTimeZone, SimpleTimeZone, and VTimeZone.) 109 * <P> 110 * The TimeZone class contains a static list containing a TimeZone object for every 111 * combination of GMT offset and daylight-savings time rules currently in use in the 112 * world, each with a unique ID. Each ID consists of a region (usually a continent or 113 * ocean) and a city in that region, separated by a slash, (for example, US Pacific 114 * Time is "America/Los_Angeles.") Because older versions of this class used 115 * three- or four-letter abbreviations instead, there is also a table that maps the older 116 * abbreviations to the newer ones (for example, "PST" maps to "America/Los_Angeles"). 117 * Anywhere the API requires an ID, you can use either form. 118 * <P> 119 * To create a new TimeZone, you call the factory function TimeZone::createTimeZone() 120 * and pass it a time zone ID. You can use the createEnumeration() function to 121 * obtain a list of all the time zone IDs recognized by createTimeZone(). 122 * <P> 123 * You can also use TimeZone::createDefault() to create a TimeZone. This function uses 124 * platform-specific APIs to produce a TimeZone for the time zone corresponding to 125 * the client's computer's physical location. For example, if you're in Japan (assuming 126 * your machine is set up correctly), TimeZone::createDefault() will return a TimeZone 127 * for Japanese Standard Time ("Asia/Tokyo"). 128 */ 129 class U_I18N_API TimeZone : public UObject { 130 public: 131 /** 132 * @stable ICU 2.0 133 */ 134 virtual ~TimeZone(); 135 136 /** 137 * Returns the "unknown" time zone. 138 * It behaves like the GMT/UTC time zone but has the 139 * <code>UCAL_UNKNOWN_ZONE_ID</code> = "Etc/Unknown". 140 * createTimeZone() returns a mutable clone of this time zone if the input ID is not recognized. 141 * 142 * @return the "unknown" time zone. 143 * @see UCAL_UNKNOWN_ZONE_ID 144 * @see createTimeZone 145 * @see getGMT 146 * @stable ICU 49 147 */ 148 static const TimeZone& U_EXPORT2 getUnknown(); 149 150 /** 151 * The GMT (=UTC) time zone has a raw offset of zero and does not use daylight 152 * savings time. This is a commonly used time zone. 153 * 154 * <p>Note: For backward compatibility reason, the ID used by the time 155 * zone returned by this method is "GMT", although the ICU's canonical 156 * ID for the GMT time zone is "Etc/GMT". 157 * 158 * @return the GMT/UTC time zone. 159 * @see getUnknown 160 * @stable ICU 2.0 161 */ 162 static const TimeZone* U_EXPORT2 getGMT(void); 163 164 /** 165 * Creates a <code>TimeZone</code> for the given ID. 166 * @param ID the ID for a <code>TimeZone</code>, such as "America/Los_Angeles", 167 * or a custom ID such as "GMT-8:00". 168 * @return the specified <code>TimeZone</code>, or a mutable clone of getUnknown() 169 * if the given ID cannot be understood or if the given ID is "Etc/Unknown". 170 * The return result is guaranteed to be non-NULL. 171 * If you require that the specific zone asked for be returned, 172 * compare the result with getUnknown() or check the ID of the return result. 173 * @stable ICU 2.0 174 */ 175 static TimeZone* U_EXPORT2 createTimeZone(const UnicodeString& ID); 176 177 /** 178 * Returns an enumeration over system time zone IDs with the given 179 * filter conditions. 180 * @param zoneType The system time zone type. 181 * @param region The ISO 3166 two-letter country code or UN M.49 182 * three-digit area code. When NULL, no filtering 183 * done by region. 184 * @param rawOffset An offset from GMT in milliseconds, ignoring 185 * the effect of daylight savings time, if any. 186 * When NULL, no filtering done by zone offset. 187 * @param ec Output param to filled in with a success or 188 * an error. 189 * @return an enumeration object, owned by the caller. 190 * @stable ICU 4.8 191 */ 192 static StringEnumeration* U_EXPORT2 createTimeZoneIDEnumeration( 193 USystemTimeZoneType zoneType, 194 const char* region, 195 const int32_t* rawOffset, 196 UErrorCode& ec); 197 198 /** 199 * Returns an enumeration over all recognized time zone IDs. (i.e., 200 * all strings that createTimeZone() accepts) 201 * 202 * @return an enumeration object, owned by the caller. 203 * @stable ICU 2.4 204 */ 205 static StringEnumeration* U_EXPORT2 createEnumeration(); 206 207 /** 208 * Returns an enumeration over time zone IDs with a given raw 209 * offset from GMT. There may be several times zones with the 210 * same GMT offset that differ in the way they handle daylight 211 * savings time. For example, the state of Arizona doesn't 212 * observe daylight savings time. If you ask for the time zone 213 * IDs corresponding to GMT-7:00, you'll get back an enumeration 214 * over two time zone IDs: "America/Denver," which corresponds to 215 * Mountain Standard Time in the winter and Mountain Daylight Time 216 * in the summer, and "America/Phoenix", which corresponds to 217 * Mountain Standard Time year-round, even in the summer. 218 * 219 * @param rawOffset an offset from GMT in milliseconds, ignoring 220 * the effect of daylight savings time, if any 221 * @return an enumeration object, owned by the caller 222 * @stable ICU 2.4 223 */ 224 static StringEnumeration* U_EXPORT2 createEnumeration(int32_t rawOffset); 225 226 /** 227 * Returns an enumeration over time zone IDs associated with the 228 * given country. Some zones are affiliated with no country 229 * (e.g., "UTC"); these may also be retrieved, as a group. 230 * 231 * @param country The ISO 3166 two-letter country code, or NULL to 232 * retrieve zones not affiliated with any country. 233 * @return an enumeration object, owned by the caller 234 * @stable ICU 2.4 235 */ 236 static StringEnumeration* U_EXPORT2 createEnumeration(const char* country); 237 238 /** 239 * Returns the number of IDs in the equivalency group that 240 * includes the given ID. An equivalency group contains zones 241 * that have the same GMT offset and rules. 242 * 243 * <p>The returned count includes the given ID; it is always >= 1. 244 * The given ID must be a system time zone. If it is not, returns 245 * zero. 246 * @param id a system time zone ID 247 * @return the number of zones in the equivalency group containing 248 * 'id', or zero if 'id' is not a valid system ID 249 * @see #getEquivalentID 250 * @stable ICU 2.0 251 */ 252 static int32_t U_EXPORT2 countEquivalentIDs(const UnicodeString& id); 253 254 /** 255 * Returns an ID in the equivalency group that 256 * includes the given ID. An equivalency group contains zones 257 * that have the same GMT offset and rules. 258 * 259 * <p>The given index must be in the range 0..n-1, where n is the 260 * value returned by <code>countEquivalentIDs(id)</code>. For 261 * some value of 'index', the returned value will be equal to the 262 * given id. If the given id is not a valid system time zone, or 263 * if 'index' is out of range, then returns an empty string. 264 * @param id a system time zone ID 265 * @param index a value from 0 to n-1, where n is the value 266 * returned by <code>countEquivalentIDs(id)</code> 267 * @return the ID of the index-th zone in the equivalency group 268 * containing 'id', or an empty string if 'id' is not a valid 269 * system ID or 'index' is out of range 270 * @see #countEquivalentIDs 271 * @stable ICU 2.0 272 */ 273 static const UnicodeString U_EXPORT2 getEquivalentID(const UnicodeString& id, 274 int32_t index); 275 276 /** 277 * Creates a new copy of the default TimeZone for this host. Unless the default time 278 * zone has already been set using adoptDefault() or setDefault(), the default is 279 * determined by querying the system using methods in TPlatformUtilities. If the 280 * system routines fail, or if they specify a TimeZone or TimeZone offset which is not 281 * recognized, the TimeZone indicated by the ID kLastResortID is instantiated 282 * and made the default. 283 * 284 * @return A default TimeZone. Clients are responsible for deleting the time zone 285 * object returned. 286 * @stable ICU 2.0 287 */ 288 static TimeZone* U_EXPORT2 createDefault(void); 289 290 /** 291 * Sets the default time zone (i.e., what's returned by createDefault()) to be the 292 * specified time zone. If NULL is specified for the time zone, the default time 293 * zone is set to the default host time zone. This call adopts the TimeZone object 294 * passed in; the client is no longer responsible for deleting it. 295 * 296 * <p>This function is not thread safe. It is an error for multiple threads 297 * to concurrently attempt to set the default time zone, or for any thread 298 * to attempt to reference the default zone while another thread is setting it. 299 * 300 * @param zone A pointer to the new TimeZone object to use as the default. 301 * @stable ICU 2.0 302 */ 303 static void U_EXPORT2 adoptDefault(TimeZone* zone); 304 305 #ifndef U_HIDE_SYSTEM_API 306 /** 307 * Same as adoptDefault(), except that the TimeZone object passed in is NOT adopted; 308 * the caller remains responsible for deleting it. 309 * 310 * <p>See the thread safety note under adoptDefault(). 311 * 312 * @param zone The given timezone. 313 * @system 314 * @stable ICU 2.0 315 */ 316 static void U_EXPORT2 setDefault(const TimeZone& zone); 317 #endif /* U_HIDE_SYSTEM_API */ 318 319 /** 320 * Returns the timezone data version currently used by ICU. 321 * @param status Output param to filled in with a success or an error. 322 * @return the version string, such as "2007f" 323 * @stable ICU 3.8 324 */ 325 static const char* U_EXPORT2 getTZDataVersion(UErrorCode& status); 326 327 /** 328 * Returns the canonical system timezone ID or the normalized 329 * custom time zone ID for the given time zone ID. 330 * @param id The input time zone ID to be canonicalized. 331 * @param canonicalID Receives the canonical system time zone ID 332 * or the custom time zone ID in normalized format. 333 * @param status Receives the status. When the given time zone ID 334 * is neither a known system time zone ID nor a 335 * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR 336 * is set. 337 * @return A reference to the result. 338 * @stable ICU 4.0 339 */ 340 static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, 341 UnicodeString& canonicalID, UErrorCode& status); 342 343 /** 344 * Returns the canonical system time zone ID or the normalized 345 * custom time zone ID for the given time zone ID. 346 * @param id The input time zone ID to be canonicalized. 347 * @param canonicalID Receives the canonical system time zone ID 348 * or the custom time zone ID in normalized format. 349 * @param isSystemID Receives if the given ID is a known system 350 * time zone ID. 351 * @param status Receives the status. When the given time zone ID 352 * is neither a known system time zone ID nor a 353 * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR 354 * is set. 355 * @return A reference to the result. 356 * @stable ICU 4.0 357 */ 358 static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, 359 UnicodeString& canonicalID, UBool& isSystemID, UErrorCode& status); 360 361 #ifndef U_HIDE_DRAFT_API 362 /** 363 * Converts a system time zone ID to an equivalent Windows time zone ID. For example, 364 * Windows time zone ID "Pacific Standard Time" is returned for input "America/Los_Angeles". 365 * 366 * <p>There are system time zones that cannot be mapped to Windows zones. When the input 367 * system time zone ID is unknown or unmappable to a Windows time zone, then the result will be 368 * empty, but the operation itself remains successful (no error status set on return). 369 * 370 * <p>This implementation utilizes <a href="http://unicode.org/cldr/charts/supplemental/zone_tzid.html"> 371 * Zone-Tzid mapping data</a>. The mapping data is updated time to time. To get the latest changes, 372 * please read the ICU user guide section <a href="http://userguide.icu-project.org/datetime/timezone#TOC-Updating-the-Time-Zone-Data"> 373 * Updating the Time Zone Data</a>. 374 * 375 * @param id A system time zone ID. 376 * @param winid Receives a Windows time zone ID. When the input system time zone ID is unknown 377 * or unmappable to a Windows time zone ID, then an empty string is set on return. 378 * @param status Receives the status. 379 * @return A reference to the result (<code>winid</code>). 380 * @see getIDForWindowsID 381 * 382 * @draft ICU 52 383 */ 384 static UnicodeString& U_EXPORT2 getWindowsID(const UnicodeString& id, 385 UnicodeString& winid, UErrorCode& status); 386 387 /** 388 * Converts a Windows time zone ID to an equivalent system time zone ID 389 * for a region. For example, system time zone ID "America/Los_Angeles" is returned 390 * for input Windows ID "Pacific Standard Time" and region "US" (or <code>null</code>), 391 * "America/Vancouver" is returned for the same Windows ID "Pacific Standard Time" and 392 * region "CA". 393 * 394 * <p>Not all Windows time zones can be mapped to system time zones. When the input 395 * Windows time zone ID is unknown or unmappable to a system time zone, then the result 396 * will be empty, but the operation itself remains successful (no error status set on return). 397 * 398 * <p>This implementation utilizes <a href="http://unicode.org/cldr/charts/supplemental/zone_tzid.html"> 399 * Zone-Tzid mapping data</a>. The mapping data is updated time to time. To get the latest changes, 400 * please read the ICU user guide section <a href="http://userguide.icu-project.org/datetime/timezone#TOC-Updating-the-Time-Zone-Data"> 401 * Updating the Time Zone Data</a>. 402 * 403 * @param winid A Windows time zone ID. 404 * @param region A null-terminated region code, or <code>NULL</code> if no regional preference. 405 * @param id Receives a system time zone ID. When the input Windows time zone ID is unknown 406 * or unmappable to a system time zone ID, then an empty string is set on return. 407 * @param status Receives the status. 408 * @return A reference to the result (<code>id</code>). 409 * @see getWindowsID 410 * 411 * @draft ICU 52 412 */ 413 static UnicodeString& U_EXPORT2 getIDForWindowsID(const UnicodeString& winid, const char* region, 414 UnicodeString& id, UErrorCode& status); 415 416 #endif /* U_HIDE_DRAFT_API */ 417 418 /** 419 * Returns true if the two TimeZones are equal. (The TimeZone version only compares 420 * IDs, but subclasses are expected to also compare the fields they add.) 421 * 422 * @param that The TimeZone object to be compared with. 423 * @return True if the given TimeZone is equal to this TimeZone; false 424 * otherwise. 425 * @stable ICU 2.0 426 */ 427 virtual UBool operator==(const TimeZone& that) const; 428 429 /** 430 * Returns true if the two TimeZones are NOT equal; that is, if operator==() returns 431 * false. 432 * 433 * @param that The TimeZone object to be compared with. 434 * @return True if the given TimeZone is not equal to this TimeZone; false 435 * otherwise. 436 * @stable ICU 2.0 437 */ 438 UBool operator!=(const TimeZone& that) const {return !operator==(that);} 439 440 /** 441 * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add 442 * to GMT to get local time in this time zone, taking daylight savings time into 443 * account) as of a particular reference date. The reference date is used to determine 444 * whether daylight savings time is in effect and needs to be figured into the offset 445 * that is returned (in other words, what is the adjusted GMT offset in this time zone 446 * at this particular date and time?). For the time zones produced by createTimeZone(), 447 * the reference data is specified according to the Gregorian calendar, and the date 448 * and time fields are local standard time. 449 * 450 * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, 451 * which returns both the raw and the DST offset for a given time. This method 452 * is retained only for backward compatibility. 453 * 454 * @param era The reference date's era 455 * @param year The reference date's year 456 * @param month The reference date's month (0-based; 0 is January) 457 * @param day The reference date's day-in-month (1-based) 458 * @param dayOfWeek The reference date's day-of-week (1-based; 1 is Sunday) 459 * @param millis The reference date's milliseconds in day, local standard time 460 * @param status Output param to filled in with a success or an error. 461 * @return The offset in milliseconds to add to GMT to get local time. 462 * @stable ICU 2.0 463 */ 464 virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, 465 uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const = 0; 466 467 /** 468 * Gets the time zone offset, for current date, modified in case of 469 * daylight savings. This is the offset to add *to* UTC to get local time. 470 * 471 * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, 472 * which returns both the raw and the DST offset for a given time. This method 473 * is retained only for backward compatibility. 474 * 475 * @param era the era of the given date. 476 * @param year the year in the given date. 477 * @param month the month in the given date. 478 * Month is 0-based. e.g., 0 for January. 479 * @param day the day-in-month of the given date. 480 * @param dayOfWeek the day-of-week of the given date. 481 * @param milliseconds the millis in day in <em>standard</em> local time. 482 * @param monthLength the length of the given month in days. 483 * @param status Output param to filled in with a success or an error. 484 * @return the offset to add *to* GMT to get local time. 485 * @stable ICU 2.0 486 */ 487 virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, 488 uint8_t dayOfWeek, int32_t milliseconds, 489 int32_t monthLength, UErrorCode& status) const = 0; 490 491 /** 492 * Returns the time zone raw and GMT offset for the given moment 493 * in time. Upon return, local-millis = GMT-millis + rawOffset + 494 * dstOffset. All computations are performed in the proleptic 495 * Gregorian calendar. The default implementation in the TimeZone 496 * class delegates to the 8-argument getOffset(). 497 * 498 * @param date moment in time for which to return offsets, in 499 * units of milliseconds from January 1, 1970 0:00 GMT, either GMT 500 * time or local wall time, depending on `local'. 501 * @param local if true, `date' is local wall time; otherwise it 502 * is in GMT time. 503 * @param rawOffset output parameter to receive the raw offset, that 504 * is, the offset not including DST adjustments 505 * @param dstOffset output parameter to receive the DST offset, 506 * that is, the offset to be added to `rawOffset' to obtain the 507 * total offset between local and GMT time. If DST is not in 508 * effect, this value is zero; otherwise it is a positive value, 509 * typically one hour. 510 * @param ec input-output error code 511 * 512 * @stable ICU 2.8 513 */ 514 virtual void getOffset(UDate date, UBool local, int32_t& rawOffset, 515 int32_t& dstOffset, UErrorCode& ec) const; 516 517 /** 518 * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add 519 * to GMT to get local time, before taking daylight savings time into account). 520 * 521 * @param offsetMillis The new raw GMT offset for this time zone. 522 * @stable ICU 2.0 523 */ 524 virtual void setRawOffset(int32_t offsetMillis) = 0; 525 526 /** 527 * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add 528 * to GMT to get local time, before taking daylight savings time into account). 529 * 530 * @return The TimeZone's raw GMT offset. 531 * @stable ICU 2.0 532 */ 533 virtual int32_t getRawOffset(void) const = 0; 534 535 /** 536 * Fills in "ID" with the TimeZone's ID. 537 * 538 * @param ID Receives this TimeZone's ID. 539 * @return A reference to 'ID' 540 * @stable ICU 2.0 541 */ 542 UnicodeString& getID(UnicodeString& ID) const; 543 544 /** 545 * Sets the TimeZone's ID to the specified value. This doesn't affect any other 546 * fields (for example, if you say< 547 * blockquote><pre> 548 * . TimeZone* foo = TimeZone::createTimeZone("America/New_York"); 549 * . foo.setID("America/Los_Angeles"); 550 * </pre>\htmlonly</blockquote>\endhtmlonly 551 * the time zone's GMT offset and daylight-savings rules don't change to those for 552 * Los Angeles. They're still those for New York. Only the ID has changed.) 553 * 554 * @param ID The new time zone ID. 555 * @stable ICU 2.0 556 */ 557 void setID(const UnicodeString& ID); 558 559 /** 560 * Enum for use with getDisplayName 561 * @stable ICU 2.4 562 */ 563 enum EDisplayType { 564 /** 565 * Selector for short display name 566 * @stable ICU 2.4 567 */ 568 SHORT = 1, 569 /** 570 * Selector for long display name 571 * @stable ICU 2.4 572 */ 573 LONG, 574 /** 575 * Selector for short generic display name 576 * @stable ICU 4.4 577 */ 578 SHORT_GENERIC, 579 /** 580 * Selector for long generic display name 581 * @stable ICU 4.4 582 */ 583 LONG_GENERIC, 584 /** 585 * Selector for short display name derived 586 * from time zone offset 587 * @stable ICU 4.4 588 */ 589 SHORT_GMT, 590 /** 591 * Selector for long display name derived 592 * from time zone offset 593 * @stable ICU 4.4 594 */ 595 LONG_GMT, 596 /** 597 * Selector for short display name derived 598 * from the time zone's fallback name 599 * @stable ICU 4.4 600 */ 601 SHORT_COMMONLY_USED, 602 /** 603 * Selector for long display name derived 604 * from the time zone's fallback name 605 * @stable ICU 4.4 606 */ 607 GENERIC_LOCATION 608 }; 609 610 /** 611 * Returns a name of this time zone suitable for presentation to the user 612 * in the default locale. 613 * This method returns the long name, not including daylight savings. 614 * If the display name is not available for the locale, 615 * then this method returns a string in the localized GMT offset format 616 * such as <code>GMT[+-]HH:mm</code>. 617 * @param result the human-readable name of this time zone in the default locale. 618 * @return A reference to 'result'. 619 * @stable ICU 2.0 620 */ 621 UnicodeString& getDisplayName(UnicodeString& result) const; 622 623 /** 624 * Returns a name of this time zone suitable for presentation to the user 625 * in the specified locale. 626 * This method returns the long name, not including daylight savings. 627 * If the display name is not available for the locale, 628 * then this method returns a string in the localized GMT offset format 629 * such as <code>GMT[+-]HH:mm</code>. 630 * @param locale the locale in which to supply the display name. 631 * @param result the human-readable name of this time zone in the given locale 632 * or in the default locale if the given locale is not recognized. 633 * @return A reference to 'result'. 634 * @stable ICU 2.0 635 */ 636 UnicodeString& getDisplayName(const Locale& locale, UnicodeString& result) const; 637 638 /** 639 * Returns a name of this time zone suitable for presentation to the user 640 * in the default locale. 641 * If the display name is not available for the locale, 642 * then this method returns a string in the localized GMT offset format 643 * such as <code>GMT[+-]HH:mm</code>. 644 * @param daylight if true, return the daylight savings name. 645 * @param style 646 * @param result the human-readable name of this time zone in the default locale. 647 * @return A reference to 'result'. 648 * @stable ICU 2.0 649 */ 650 UnicodeString& getDisplayName(UBool daylight, EDisplayType style, UnicodeString& result) const; 651 652 /** 653 * Returns a name of this time zone suitable for presentation to the user 654 * in the specified locale. 655 * If the display name is not available for the locale, 656 * then this method returns a string in the localized GMT offset format 657 * such as <code>GMT[+-]HH:mm</code>. 658 * @param daylight if true, return the daylight savings name. 659 * @param style 660 * @param locale the locale in which to supply the display name. 661 * @param result the human-readable name of this time zone in the given locale 662 * or in the default locale if the given locale is not recognized. 663 * @return A refence to 'result'. 664 * @stable ICU 2.0 665 */ 666 UnicodeString& getDisplayName(UBool daylight, EDisplayType style, const Locale& locale, UnicodeString& result) const; 667 668 /** 669 * Queries if this time zone uses daylight savings time. 670 * @return true if this time zone uses daylight savings time, 671 * false, otherwise. 672 * <p><strong>Note:</strong>The default implementation of 673 * ICU TimeZone uses the tz database, which supports historic 674 * rule changes, for system time zones. With the implementation, 675 * there are time zones that used daylight savings time in the 676 * past, but no longer used currently. For example, Asia/Tokyo has 677 * never used daylight savings time since 1951. Most clients would 678 * expect that this method to return <code>FALSE</code> for such case. 679 * The default implementation of this method returns <code>TRUE</code> 680 * when the time zone uses daylight savings time in the current 681 * (Gregorian) calendar year. 682 * <p>In Java 7, <code>observesDaylightTime()</code> was added in 683 * addition to <code>useDaylightTime()</code>. In Java, <code>useDaylightTime()</code> 684 * only checks if daylight saving time is observed by the last known 685 * rule. This specification might not be what most users would expect 686 * if daylight saving time is currently observed, but not scheduled 687 * in future. In this case, Java's <code>userDaylightTime()</code> returns 688 * <code>false</code>. To resolve the issue, Java 7 added <code>observesDaylightTime()</code>, 689 * which takes the current rule into account. The method <code>observesDaylightTime()</code> 690 * was added in ICU4J for supporting API signature compatibility with JDK. 691 * In general, ICU4C also provides JDK compatible methods, but the current 692 * implementation <code>userDaylightTime()</code> serves the purpose 693 * (takes the current rule into account), <code>observesDaylightTime()</code> 694 * is not added in ICU4C. In addition to <code>useDaylightTime()</code>, ICU4C 695 * <code>BasicTimeZone</code> class (Note that <code>TimeZone::createTimeZone(const UnicodeString &ID)</code> 696 * always returns a <code>BasicTimeZone</code>) provides a series of methods allowing 697 * historic and future time zone rule iteration, so you can check if daylight saving 698 * time is observed or not within a given period. 699 * 700 * @stable ICU 2.0 701 */ 702 virtual UBool useDaylightTime(void) const = 0; 703 704 /** 705 * Queries if the given date is in daylight savings time in 706 * this time zone. 707 * This method is wasteful since it creates a new GregorianCalendar and 708 * deletes it each time it is called. This is a deprecated method 709 * and provided only for Java compatibility. 710 * 711 * @param date the given UDate. 712 * @param status Output param filled in with success/error code. 713 * @return true if the given date is in daylight savings time, 714 * false, otherwise. 715 * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead. 716 */ 717 virtual UBool inDaylightTime(UDate date, UErrorCode& status) const = 0; 718 719 /** 720 * Returns true if this zone has the same rule and offset as another zone. 721 * That is, if this zone differs only in ID, if at all. 722 * @param other the <code>TimeZone</code> object to be compared with 723 * @return true if the given zone is the same as this one, 724 * with the possible exception of the ID 725 * @stable ICU 2.0 726 */ 727 virtual UBool hasSameRules(const TimeZone& other) const; 728 729 /** 730 * Clones TimeZone objects polymorphically. Clients are responsible for deleting 731 * the TimeZone object cloned. 732 * 733 * @return A new copy of this TimeZone object. 734 * @stable ICU 2.0 735 */ 736 virtual TimeZone* clone(void) const = 0; 737 738 /** 739 * Return the class ID for this class. This is useful only for 740 * comparing to a return value from getDynamicClassID(). 741 * @return The class ID for all objects of this class. 742 * @stable ICU 2.0 743 */ 744 static UClassID U_EXPORT2 getStaticClassID(void); 745 746 /** 747 * Returns a unique class ID POLYMORPHICALLY. This method is to 748 * implement a simple version of RTTI, since not all C++ compilers support genuine 749 * RTTI. Polymorphic operator==() and clone() methods call this method. 750 * <P> 751 * Concrete subclasses of TimeZone must use the UOBJECT_DEFINE_RTTI_IMPLEMENTATION 752 * macro from uobject.h in their implementation to provide correct RTTI information. 753 * @return The class ID for this object. All objects of a given class have the 754 * same class ID. Objects of other classes have different class IDs. 755 * @stable ICU 2.0 756 */ 757 virtual UClassID getDynamicClassID(void) const = 0; 758 759 /** 760 * Returns the amount of time to be added to local standard time 761 * to get local wall clock time. 762 * <p> 763 * The default implementation always returns 3600000 milliseconds 764 * (i.e., one hour) if this time zone observes Daylight Saving 765 * Time. Otherwise, 0 (zero) is returned. 766 * <p> 767 * If an underlying TimeZone implementation subclass supports 768 * historical Daylight Saving Time changes, this method returns 769 * the known latest daylight saving value. 770 * 771 * @return the amount of saving time in milliseconds 772 * @stable ICU 3.6 773 */ 774 virtual int32_t getDSTSavings() const; 775 776 /** 777 * Gets the region code associated with the given 778 * system time zone ID. The region code is either ISO 3166 779 * 2-letter country code or UN M.49 3-digit area code. 780 * When the time zone is not associated with a specific location, 781 * for example - "Etc/UTC", "EST5EDT", then this method returns 782 * "001" (UN M.49 area code for World). 783 * 784 * @param id The system time zone ID. 785 * @param region Output buffer for receiving the region code. 786 * @param capacity The size of the output buffer. 787 * @param status Receives the status. When the given time zone ID 788 * is not a known system time zone ID, 789 * U_ILLEGAL_ARGUMENT_ERROR is set. 790 * @return The length of the output region code. 791 * @stable ICU 4.8 792 */ 793 static int32_t U_EXPORT2 getRegion(const UnicodeString& id, 794 char *region, int32_t capacity, UErrorCode& status); 795 796 protected: 797 798 /** 799 * Default constructor. ID is initialized to the empty string. 800 * @stable ICU 2.0 801 */ 802 TimeZone(); 803 804 /** 805 * Construct a TimeZone with a given ID. 806 * @param id a system time zone ID 807 * @stable ICU 2.0 808 */ 809 TimeZone(const UnicodeString &id); 810 811 /** 812 * Copy constructor. 813 * @param source the object to be copied. 814 * @stable ICU 2.0 815 */ 816 TimeZone(const TimeZone& source); 817 818 /** 819 * Default assignment operator. 820 * @param right the object to be copied. 821 * @stable ICU 2.0 822 */ 823 TimeZone& operator=(const TimeZone& right); 824 825 #ifndef U_HIDE_INTERNAL_API 826 /** 827 * Utility function. For internally loading rule data. 828 * @param top Top resource bundle for tz data 829 * @param ruleid ID of rule to load 830 * @param oldbundle Old bundle to reuse or NULL 831 * @param status Status parameter 832 * @return either a new bundle or *oldbundle 833 * @internal 834 */ 835 static UResourceBundle* loadRule(const UResourceBundle* top, const UnicodeString& ruleid, UResourceBundle* oldbundle, UErrorCode&status); 836 #endif /* U_HIDE_INTERNAL_API */ 837 838 private: 839 friend class ZoneMeta; 840 841 842 static TimeZone* createCustomTimeZone(const UnicodeString&); // Creates a time zone based on the string. 843 844 /** 845 * Finds the given ID in the Olson tzdata. If the given ID is found in the tzdata, 846 * returns the pointer to the ID resource. This method is exposed through ZoneMeta class 847 * for ICU internal implementation and useful for building hashtable using a time zone 848 * ID as a key. 849 * @param id zone id string 850 * @return the pointer of the ID resource, or NULL. 851 */ 852 static const UChar* findID(const UnicodeString& id); 853 854 /** 855 * Resolve a link in Olson tzdata. When the given id is known and it's not a link, 856 * the id itself is returned. When the given id is known and it is a link, then 857 * dereferenced zone id is returned. When the given id is unknown, then it returns 858 * NULL. 859 * @param id zone id string 860 * @return the dereferenced zone or NULL 861 */ 862 static const UChar* dereferOlsonLink(const UnicodeString& id); 863 864 /** 865 * Returns the region code associated with the given zone, 866 * or NULL if the zone is not known. 867 * @param id zone id string 868 * @return the region associated with the given zone 869 */ 870 static const UChar* getRegion(const UnicodeString& id); 871 872 public: 873 #ifndef U_HIDE_INTERNAL_API 874 /** 875 * Returns the region code associated with the given zone, 876 * or NULL if the zone is not known. 877 * @param id zone id string 878 * @param status Status parameter 879 * @return the region associated with the given zone 880 * @internal 881 */ 882 static const UChar* getRegion(const UnicodeString& id, UErrorCode& status); 883 #endif /* U_HIDE_INTERNAL_API */ 884 885 private: 886 /** 887 * Parses the given custom time zone identifier 888 * @param id id A string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or 889 * GMT[+-]hh. 890 * @param sign Receves parsed sign, 1 for positive, -1 for negative. 891 * @param hour Receives parsed hour field 892 * @param minute Receives parsed minute field 893 * @param second Receives parsed second field 894 * @return Returns TRUE when the given custom id is valid. 895 */ 896 static UBool parseCustomID(const UnicodeString& id, int32_t& sign, int32_t& hour, 897 int32_t& minute, int32_t& second); 898 899 /** 900 * Parse a custom time zone identifier and return the normalized 901 * custom time zone identifier for the given custom id string. 902 * @param id a string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or 903 * GMT[+-]hh. 904 * @param normalized Receives the normalized custom ID 905 * @param status Receives the status. When the input ID string is invalid, 906 * U_ILLEGAL_ARGUMENT_ERROR is set. 907 * @return The normalized custom id string. 908 */ 909 static UnicodeString& getCustomID(const UnicodeString& id, UnicodeString& normalized, 910 UErrorCode& status); 911 912 /** 913 * Returns the normalized custome time zone ID for the given offset fields. 914 * @param hour offset hours 915 * @param min offset minutes 916 * @param sec offset seconds 917 * @param negative sign of the offset, TRUE for negative offset. 918 * @param id Receves the format result (normalized custom ID) 919 * @return The reference to id 920 */ 921 static UnicodeString& formatCustomID(int32_t hour, int32_t min, int32_t sec, 922 UBool negative, UnicodeString& id); 923 924 UnicodeString fID; // this time zone's ID 925 926 friend class TZEnumeration; 927 }; 928 929 930 // ------------------------------------- 931 932 inline UnicodeString& 933 TimeZone::getID(UnicodeString& ID) const 934 { 935 ID = fID; 936 return ID; 937 } 938 939 // ------------------------------------- 940 941 inline void 942 TimeZone::setID(const UnicodeString& ID) 943 { 944 fID = ID; 945 } 946 U_NAMESPACE_END 947 948 #endif /* #if !UCONFIG_NO_FORMATTING */ 949 950 #endif //_TIMEZONE 951 //eof 952
