1 /************************************************************************* 2 * Copyright (c) 1997-2009, 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 43 U_NAMESPACE_BEGIN 44 45 class StringEnumeration; 46 47 /** 48 * 49 * <code>TimeZone</code> represents a time zone offset, and also figures out daylight 50 * savings. 51 * 52 * <p> 53 * Typically, you get a <code>TimeZone</code> using <code>createDefault</code> 54 * which creates a <code>TimeZone</code> based on the time zone where the program 55 * is running. For example, for a program running in Japan, <code>createDefault</code> 56 * creates a <code>TimeZone</code> object based on Japanese Standard Time. 57 * 58 * <p> 59 * You can also get a <code>TimeZone</code> using <code>createTimeZone</code> along 60 * with a time zone ID. For instance, the time zone ID for the US Pacific 61 * Time zone is "America/Los_Angeles". So, you can get a Pacific Time <code>TimeZone</code> object 62 * with: 63 * \htmlonly<blockquote>\endhtmlonly 64 * <pre> 65 * TimeZone *tz = TimeZone::createTimeZone("America/Los_Angeles"); 66 * </pre> 67 * \htmlonly</blockquote>\endhtmlonly 68 * You can use <code>getAvailableIDs</code> method to iterate through 69 * all the supported time zone IDs. You can then choose a 70 * supported ID to get a <code>TimeZone</code>. 71 * If the time zone you want is not represented by one of the 72 * supported IDs, then you can create a custom time zone ID with 73 * the following syntax: 74 * 75 * \htmlonly<blockquote>\endhtmlonly 76 * <pre> 77 * GMT[+|-]hh[[:]mm] 78 * </pre> 79 * \htmlonly</blockquote>\endhtmlonly 80 * 81 * For example, you might specify GMT+14:00 as a custom 82 * time zone ID. The <code>TimeZone</code> that is returned 83 * when you specify a custom time zone ID does not include 84 * daylight savings time. 85 * 86 * TimeZone is an abstract class representing a time zone. A TimeZone is needed for 87 * Calendar to produce local time for a particular time zone. A TimeZone comprises 88 * three basic pieces of information: 89 * <ul> 90 * <li>A time zone offset; that, is the number of milliseconds to add or subtract 91 * from a time expressed in terms of GMT to convert it to the same time in that 92 * time zone (without taking daylight savings time into account).</li> 93 * <li>Logic necessary to take daylight savings time into account if daylight savings 94 * time is observed in that time zone (e.g., the days and hours on which daylight 95 * savings time begins and ends).</li> 96 * <li>An ID. This is a text string that uniquely identifies the time zone.</li> 97 * </ul> 98 * 99 * (Only the ID is actually implemented in TimeZone; subclasses of TimeZone may handle 100 * daylight savings time and GMT offset in different ways. Currently we only have one 101 * TimeZone subclass: SimpleTimeZone.) 102 * <P> 103 * The TimeZone class contains a static list containing a TimeZone object for every 104 * combination of GMT offset and daylight-savings time rules currently in use in the 105 * world, each with a unique ID. Each ID consists of a region (usually a continent or 106 * ocean) and a city in that region, separated by a slash, (for example, US Pacific 107 * Time is "America/Los_Angeles.") Because older versions of this class used 108 * three- or four-letter abbreviations instead, there is also a table that maps the older 109 * abbreviations to the newer ones (for example, "PST" maps to "America/Los_Angeles"). 110 * Anywhere the API requires an ID, you can use either form. 111 * <P> 112 * To create a new TimeZone, you call the factory function TimeZone::createTimeZone() 113 * and pass it a time zone ID. You can use the createEnumeration() function to 114 * obtain a list of all the time zone IDs recognized by createTimeZone(). 115 * <P> 116 * You can also use TimeZone::createDefault() to create a TimeZone. This function uses 117 * platform-specific APIs to produce a TimeZone for the time zone corresponding to 118 * the client's computer's physical location. For example, if you're in Japan (assuming 119 * your machine is set up correctly), TimeZone::createDefault() will return a TimeZone 120 * for Japanese Standard Time ("Asia/Tokyo"). 121 */ 122 class U_I18N_API TimeZone : public UObject { 123 public: 124 /** 125 * @stable ICU 2.0 126 */ 127 virtual ~TimeZone(); 128 129 /** 130 * The GMT time zone has a raw offset of zero and does not use daylight 131 * savings time. This is a commonly used time zone. 132 * @return the GMT time zone. 133 * @stable ICU 2.0 134 */ 135 static const TimeZone* U_EXPORT2 getGMT(void); 136 137 /** 138 * Creates a <code>TimeZone</code> for the given ID. 139 * @param ID the ID for a <code>TimeZone</code>, such as "America/Los_Angeles", 140 * or a custom ID such as "GMT-8:00". 141 * @return the specified <code>TimeZone</code>, or the GMT zone if the given ID 142 * cannot be understood. Return result guaranteed to be non-null. If you 143 * require that the specific zone asked for be returned, check the ID of the 144 * return result. 145 * @stable ICU 2.0 146 */ 147 static TimeZone* U_EXPORT2 createTimeZone(const UnicodeString& ID); 148 149 /** 150 * Returns an enumeration over all recognized time zone IDs. (i.e., 151 * all strings that createTimeZone() accepts) 152 * 153 * @return an enumeration object, owned by the caller. 154 * @stable ICU 2.4 155 */ 156 static StringEnumeration* U_EXPORT2 createEnumeration(); 157 158 /** 159 * Returns an enumeration over time zone IDs with a given raw 160 * offset from GMT. There may be several times zones with the 161 * same GMT offset that differ in the way they handle daylight 162 * savings time. For example, the state of Arizona doesn't 163 * observe daylight savings time. If you ask for the time zone 164 * IDs corresponding to GMT-7:00, you'll get back an enumeration 165 * over two time zone IDs: "America/Denver," which corresponds to 166 * Mountain Standard Time in the winter and Mountain Daylight Time 167 * in the summer, and "America/Phoenix", which corresponds to 168 * Mountain Standard Time year-round, even in the summer. 169 * 170 * @param rawOffset an offset from GMT in milliseconds, ignoring 171 * the effect of daylight savings time, if any 172 * @return an enumeration object, owned by the caller 173 * @stable ICU 2.4 174 */ 175 static StringEnumeration* U_EXPORT2 createEnumeration(int32_t rawOffset); 176 177 /** 178 * Returns an enumeration over time zone IDs associated with the 179 * given country. Some zones are affiliated with no country 180 * (e.g., "UTC"); these may also be retrieved, as a group. 181 * 182 * @param country The ISO 3166 two-letter country code, or NULL to 183 * retrieve zones not affiliated with any country. 184 * @return an enumeration object, owned by the caller 185 * @stable ICU 2.4 186 */ 187 static StringEnumeration* U_EXPORT2 createEnumeration(const char* country); 188 189 #ifdef U_USE_TIMEZONE_OBSOLETE_2_8 190 /** 191 * Returns a list of time zone IDs, one for each time zone with a given GMT offset. 192 * The return value is a list because there may be several times zones with the same 193 * GMT offset that differ in the way they handle daylight savings time. For example, 194 * the state of Arizona doesn't observe Daylight Savings time. So if you ask for 195 * the time zone IDs corresponding to GMT-7:00, you'll get back two time zone IDs: 196 * "America/Denver," which corresponds to Mountain Standard Time in the winter and 197 * Mountain Daylight Time in the summer, and "America/Phoenix", which corresponds to 198 * Mountain Standard Time year-round, even in the summer. 199 * <P> 200 * The caller owns the list that is returned, but does not own the strings contained 201 * in that list. Delete the array with uprv_free(), but DON'T delete the elements in the array. 202 * 203 * <p>NOTE: uprv_free() is declared in the private header source/common/cmemory.h. 204 * 205 * @param rawOffset An offset from GMT in milliseconds. 206 * @param numIDs Receives the number of items in the array that is returned. 207 * @return An array of UnicodeString pointers, where each UnicodeString is 208 * a time zone ID for a time zone with the given GMT offset. If 209 * there is no time zone that matches the GMT offset 210 * specified, NULL is returned. 211 * @obsolete ICU 2.8. Use createEnumeration(int32_t) instead since this API will be removed in that release. 212 */ 213 static const UnicodeString** createAvailableIDs(int32_t rawOffset, int32_t& numIDs); 214 215 /** 216 * Returns a list of time zone IDs associated with the given 217 * country. Some zones are affiliated with no country (e.g., 218 * "UTC"); these may also be retrieved, as a group. 219 * 220 * <P>The caller owns the list that is returned, but does not own 221 * the strings contained in that list. Delete the array with uprv_free(), but 222 * <b>DON'T</b> delete the elements in the array. 223 * 224 * <p>NOTE: uprv_free() is declared in the private header source/common/cmemory.h. 225 * 226 * @param country The ISO 3166 two-letter country code, or NULL to 227 * retrieve zones not affiliated with any country. 228 * @param numIDs Receives the number of items in the array that is 229 * returned. 230 * @return An array of UnicodeString pointers, where each 231 * UnicodeString is a time zone ID for a time zone with the given 232 * country. If there is no time zone that matches the country 233 * specified, NULL is returned. 234 * @obsolete ICU 2.8. Use createEnumeration(const char*) instead since this API will be removed in that release. 235 */ 236 static const UnicodeString** createAvailableIDs(const char* country, 237 int32_t& numIDs); 238 239 /** 240 * Returns a list of all time zone IDs supported by the TimeZone class (i.e., all 241 * IDs that it's legal to pass to createTimeZone()). The caller owns the list that 242 * is returned, but does not own the strings contained in that list. Delete the array with uprv_free(), 243 * but DON'T delete the elements in the array. 244 * 245 * <p>NOTE: uprv_free() is declared in the private header source/common/cmemory.h. 246 * 247 * @param numIDs Receives the number of zone IDs returned. 248 * @return An array of UnicodeString pointers, where each is a time zone ID 249 * supported by the TimeZone class. 250 * @obsolete ICU 2.8. Use createEnumeration(void) instead since this API will be removed in that release. 251 */ 252 static const UnicodeString** createAvailableIDs(int32_t& numIDs); 253 #endif 254 255 /** 256 * Returns the number of IDs in the equivalency group that 257 * includes the given ID. An equivalency group contains zones 258 * that have the same GMT offset and rules. 259 * 260 * <p>The returned count includes the given ID; it is always >= 1. 261 * The given ID must be a system time zone. If it is not, returns 262 * zero. 263 * @param id a system time zone ID 264 * @return the number of zones in the equivalency group containing 265 * 'id', or zero if 'id' is not a valid system ID 266 * @see #getEquivalentID 267 * @stable ICU 2.0 268 */ 269 static int32_t U_EXPORT2 countEquivalentIDs(const UnicodeString& id); 270 271 /** 272 * Returns an ID in the equivalency group that 273 * includes the given ID. An equivalency group contains zones 274 * that have the same GMT offset and rules. 275 * 276 * <p>The given index must be in the range 0..n-1, where n is the 277 * value returned by <code>countEquivalentIDs(id)</code>. For 278 * some value of 'index', the returned value will be equal to the 279 * given id. If the given id is not a valid system time zone, or 280 * if 'index' is out of range, then returns an empty string. 281 * @param id a system time zone ID 282 * @param index a value from 0 to n-1, where n is the value 283 * returned by <code>countEquivalentIDs(id)</code> 284 * @return the ID of the index-th zone in the equivalency group 285 * containing 'id', or an empty string if 'id' is not a valid 286 * system ID or 'index' is out of range 287 * @see #countEquivalentIDs 288 * @stable ICU 2.0 289 */ 290 static const UnicodeString U_EXPORT2 getEquivalentID(const UnicodeString& id, 291 int32_t index); 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 /** 308 * Sets the default time zone (i.e., what's returned by createDefault()) to be the 309 * specified time zone. If NULL is specified for the time zone, the default time 310 * zone is set to the default host time zone. This call adopts the TimeZone object 311 * passed in; the clent is no longer responsible for deleting it. 312 * 313 * @param zone A pointer to the new TimeZone object to use as the default. 314 * @stable ICU 2.0 315 */ 316 static void U_EXPORT2 adoptDefault(TimeZone* zone); 317 318 /** 319 * Same as adoptDefault(), except that the TimeZone object passed in is NOT adopted; 320 * the caller remains responsible for deleting it. 321 * 322 * @param zone The given timezone. 323 * @system 324 */ 325 static void U_EXPORT2 setDefault(const TimeZone& zone); 326 327 /** 328 * Returns the timezone data version currently used by ICU. 329 * @param status Output param to filled in with a success or an error. 330 * @return the version string, such as "2007f" 331 * @stable ICU 3.8 332 */ 333 static const char* U_EXPORT2 getTZDataVersion(UErrorCode& status); 334 335 /** 336 * Returns the canonical system timezone ID or the normalized 337 * custom time zone ID for the given time zone ID. 338 * @param id The input time zone ID to be canonicalized. 339 * @param canonicalID Receives the canonical system time zone ID 340 * or the custom time zone ID in normalized format. 341 * @param status Recevies the status. When the given time zone ID 342 * is neither a known system time zone ID nor a 343 * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR 344 * is set. 345 * @return A reference to the result. 346 * @stable ICU 4.0 347 */ 348 static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, 349 UnicodeString& canonicalID, UErrorCode& status); 350 351 /** 352 * Returns the canonical system time zone ID or the normalized 353 * custom time zone ID for the given time zone ID. 354 * @param id The input time zone ID to be canonicalized. 355 * @param canonicalID Receives the canonical system time zone ID 356 * or the custom time zone ID in normalized format. 357 * @param isSystemID Receives if the given ID is a known system 358 * time zone ID. 359 * @param status Recevies the status. When the given time zone ID 360 * is neither a known system time zone ID nor a 361 * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR 362 * is set. 363 * @return A reference to the result. 364 * @stable ICU 4.0 365 */ 366 static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, 367 UnicodeString& canonicalID, UBool& isSystemID, UErrorCode& status); 368 369 /** 370 * Returns true if the two TimeZones are equal. (The TimeZone version only compares 371 * IDs, but subclasses are expected to also compare the fields they add.) 372 * 373 * @param that The TimeZone object to be compared with. 374 * @return True if the given TimeZone is equal to this TimeZone; false 375 * otherwise. 376 * @stable ICU 2.0 377 */ 378 virtual UBool operator==(const TimeZone& that) const; 379 380 /** 381 * Returns true if the two TimeZones are NOT equal; that is, if operator==() returns 382 * false. 383 * 384 * @param that The TimeZone object to be compared with. 385 * @return True if the given TimeZone is not equal to this TimeZone; false 386 * otherwise. 387 * @stable ICU 2.0 388 */ 389 UBool operator!=(const TimeZone& that) const {return !operator==(that);} 390 391 /** 392 * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add 393 * to GMT to get local time in this time zone, taking daylight savings time into 394 * account) as of a particular reference date. The reference date is used to determine 395 * whether daylight savings time is in effect and needs to be figured into the offset 396 * that is returned (in other words, what is the adjusted GMT offset in this time zone 397 * at this particular date and time?). For the time zones produced by createTimeZone(), 398 * the reference data is specified according to the Gregorian calendar, and the date 399 * and time fields are local standard time. 400 * 401 * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, 402 * which returns both the raw and the DST offset for a given time. This method 403 * is retained only for backward compatibility. 404 * 405 * @param era The reference date's era 406 * @param year The reference date's year 407 * @param month The reference date's month (0-based; 0 is January) 408 * @param day The reference date's day-in-month (1-based) 409 * @param dayOfWeek The reference date's day-of-week (1-based; 1 is Sunday) 410 * @param millis The reference date's milliseconds in day, local standard time 411 * @param status Output param to filled in with a success or an error. 412 * @return The offset in milliseconds to add to GMT to get local time. 413 * @stable ICU 2.0 414 */ 415 virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, 416 uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const = 0; 417 418 /** 419 * Gets the time zone offset, for current date, modified in case of 420 * daylight savings. This is the offset to add *to* UTC to get local time. 421 * 422 * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, 423 * which returns both the raw and the DST offset for a given time. This method 424 * is retained only for backward compatibility. 425 * 426 * @param era the era of the given date. 427 * @param year the year in the given date. 428 * @param month the month in the given date. 429 * Month is 0-based. e.g., 0 for January. 430 * @param day the day-in-month of the given date. 431 * @param dayOfWeek the day-of-week of the given date. 432 * @param milliseconds the millis in day in <em>standard</em> local time. 433 * @param monthLength the length of the given month in days. 434 * @param status Output param to filled in with a success or an error. 435 * @return the offset to add *to* GMT to get local time. 436 * @stable ICU 2.0 437 */ 438 virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, 439 uint8_t dayOfWeek, int32_t milliseconds, 440 int32_t monthLength, UErrorCode& status) const = 0; 441 442 /** 443 * Returns the time zone raw and GMT offset for the given moment 444 * in time. Upon return, local-millis = GMT-millis + rawOffset + 445 * dstOffset. All computations are performed in the proleptic 446 * Gregorian calendar. The default implementation in the TimeZone 447 * class delegates to the 8-argument getOffset(). 448 * 449 * @param date moment in time for which to return offsets, in 450 * units of milliseconds from January 1, 1970 0:00 GMT, either GMT 451 * time or local wall time, depending on `local'. 452 * @param local if true, `date' is local wall time; otherwise it 453 * is in GMT time. 454 * @param rawOffset output parameter to receive the raw offset, that 455 * is, the offset not including DST adjustments 456 * @param dstOffset output parameter to receive the DST offset, 457 * that is, the offset to be added to `rawOffset' to obtain the 458 * total offset between local and GMT time. If DST is not in 459 * effect, this value is zero; otherwise it is a positive value, 460 * typically one hour. 461 * @param ec input-output error code 462 * 463 * @stable ICU 2.8 464 */ 465 virtual void getOffset(UDate date, UBool local, int32_t& rawOffset, 466 int32_t& dstOffset, UErrorCode& ec) const; 467 468 /** 469 * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add 470 * to GMT to get local time, before taking daylight savings time into account). 471 * 472 * @param offsetMillis The new raw GMT offset for this time zone. 473 * @stable ICU 2.0 474 */ 475 virtual void setRawOffset(int32_t offsetMillis) = 0; 476 477 /** 478 * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add 479 * to GMT to get local time, before taking daylight savings time into account). 480 * 481 * @return The TimeZone's raw GMT offset. 482 * @stable ICU 2.0 483 */ 484 virtual int32_t getRawOffset(void) const = 0; 485 486 /** 487 * Fills in "ID" with the TimeZone's ID. 488 * 489 * @param ID Receives this TimeZone's ID. 490 * @return A reference to 'ID' 491 * @stable ICU 2.0 492 */ 493 UnicodeString& getID(UnicodeString& ID) const; 494 495 /** 496 * Sets the TimeZone's ID to the specified value. This doesn't affect any other 497 * fields (for example, if you say< 498 * blockquote><pre> 499 * . TimeZone* foo = TimeZone::createTimeZone("America/New_York"); 500 * . foo.setID("America/Los_Angeles"); 501 * </pre>\htmlonly</blockquote>\endhtmlonly 502 * the time zone's GMT offset and daylight-savings rules don't change to those for 503 * Los Angeles. They're still those for New York. Only the ID has changed.) 504 * 505 * @param ID The new time zone ID. 506 * @stable ICU 2.0 507 */ 508 void setID(const UnicodeString& ID); 509 510 /** 511 * Enum for use with getDisplayName 512 * @stable ICU 2.4 513 */ 514 enum EDisplayType { 515 /** 516 * Selector for short display name 517 * @stable ICU 2.4 518 */ 519 SHORT = 1, 520 /** 521 * Selector for long display name 522 * @stable ICU 2.4 523 */ 524 LONG 525 }; 526 527 /** 528 * Returns a name of this time zone suitable for presentation to the user 529 * in the default locale. 530 * This method returns the long name, not including daylight savings. 531 * If the display name is not available for the locale, 532 * then this method returns a string in the format 533 * <code>GMT[+-]hh:mm</code>. 534 * @param result the human-readable name of this time zone in the default locale. 535 * @return A reference to 'result'. 536 * @stable ICU 2.0 537 */ 538 UnicodeString& getDisplayName(UnicodeString& result) const; 539 540 /** 541 * Returns a name of this time zone suitable for presentation to the user 542 * in the specified locale. 543 * This method returns the long name, not including daylight savings. 544 * If the display name is not available for the locale, 545 * then this method returns a string in the format 546 * <code>GMT[+-]hh:mm</code>. 547 * @param locale the locale in which to supply the display name. 548 * @param result the human-readable name of this time zone in the given locale 549 * or in the default locale if the given locale is not recognized. 550 * @return A reference to 'result'. 551 * @stable ICU 2.0 552 */ 553 UnicodeString& getDisplayName(const Locale& locale, UnicodeString& result) const; 554 555 /** 556 * Returns a name of this time zone suitable for presentation to the user 557 * in the default locale. 558 * If the display name is not available for the locale, 559 * then this method returns a string in the format 560 * <code>GMT[+-]hh:mm</code>. 561 * @param daylight if true, return the daylight savings name. 562 * @param style either <code>LONG</code> or <code>SHORT</code> 563 * @param result the human-readable name of this time zone in the default locale. 564 * @return A reference to 'result'. 565 * @stable ICU 2.0 566 */ 567 UnicodeString& getDisplayName(UBool daylight, EDisplayType style, UnicodeString& result) const; 568 569 /** 570 * Returns a name of this time zone suitable for presentation to the user 571 * in the specified locale. 572 * If the display name is not available for the locale, 573 * then this method returns a string in the format 574 * <code>GMT[+-]hh:mm</code>. 575 * @param daylight if true, return the daylight savings name. 576 * @param style either <code>LONG</code> or <code>SHORT</code> 577 * @param locale the locale in which to supply the display name. 578 * @param result the human-readable name of this time zone in the given locale 579 * or in the default locale if the given locale is not recognized. 580 * @return A refence to 'result'. 581 * @stable ICU 2.0 582 */ 583 UnicodeString& getDisplayName(UBool daylight, EDisplayType style, const Locale& locale, UnicodeString& result) const; 584 585 /** 586 * Queries if this time zone uses daylight savings time. 587 * @return true if this time zone uses daylight savings time, 588 * false, otherwise. 589 * @stable ICU 2.0 590 */ 591 virtual UBool useDaylightTime(void) const = 0; 592 593 /** 594 * Queries if the given date is in daylight savings time in 595 * this time zone. 596 * This method is wasteful since it creates a new GregorianCalendar and 597 * deletes it each time it is called. This is a deprecated method 598 * and provided only for Java compatibility. 599 * 600 * @param date the given UDate. 601 * @param status Output param filled in with success/error code. 602 * @return true if the given date is in daylight savings time, 603 * false, otherwise. 604 * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead. 605 */ 606 virtual UBool inDaylightTime(UDate date, UErrorCode& status) const = 0; 607 608 /** 609 * Returns true if this zone has the same rule and offset as another zone. 610 * That is, if this zone differs only in ID, if at all. 611 * @param other the <code>TimeZone</code> object to be compared with 612 * @return true if the given zone is the same as this one, 613 * with the possible exception of the ID 614 * @stable ICU 2.0 615 */ 616 virtual UBool hasSameRules(const TimeZone& other) const; 617 618 /** 619 * Clones TimeZone objects polymorphically. Clients are responsible for deleting 620 * the TimeZone object cloned. 621 * 622 * @return A new copy of this TimeZone object. 623 * @stable ICU 2.0 624 */ 625 virtual TimeZone* clone(void) const = 0; 626 627 /** 628 * Return the class ID for this class. This is useful only for 629 * comparing to a return value from getDynamicClassID(). 630 * @return The class ID for all objects of this class. 631 * @stable ICU 2.0 632 */ 633 static UClassID U_EXPORT2 getStaticClassID(void); 634 635 /** 636 * Returns a unique class ID POLYMORPHICALLY. This method is to 637 * implement a simple version of RTTI, since not all C++ compilers support genuine 638 * RTTI. Polymorphic operator==() and clone() methods call this method. 639 * <P> 640 * Concrete subclasses of TimeZone must use the UOBJECT_DEFINE_RTTI_IMPLEMENTATION 641 * macro from uobject.h in their implementation to provide correct RTTI information. 642 * @return The class ID for this object. All objects of a given class have the 643 * same class ID. Objects of other classes have different class IDs. 644 * @stable ICU 2.0 645 */ 646 virtual UClassID getDynamicClassID(void) const = 0; 647 648 /** 649 * Returns the amount of time to be added to local standard time 650 * to get local wall clock time. 651 * <p> 652 * The default implementation always returns 3600000 milliseconds 653 * (i.e., one hour) if this time zone observes Daylight Saving 654 * Time. Otherwise, 0 (zero) is returned. 655 * <p> 656 * If an underlying TimeZone implementation subclass supports 657 * historical Daylight Saving Time changes, this method returns 658 * the known latest daylight saving value. 659 * 660 * @return the amount of saving time in milliseconds 661 * @stable ICU 3.6 662 */ 663 virtual int32_t getDSTSavings() const; 664 665 protected: 666 667 /** 668 * Default constructor. ID is initialized to the empty string. 669 * @stable ICU 2.0 670 */ 671 TimeZone(); 672 673 /** 674 * Construct a TimeZone with a given ID. 675 * @param id a system time zone ID 676 * @stable ICU 2.0 677 */ 678 TimeZone(const UnicodeString &id); 679 680 /** 681 * Copy constructor. 682 * @param source the object to be copied. 683 * @stable ICU 2.0 684 */ 685 TimeZone(const TimeZone& source); 686 687 /** 688 * Default assignment operator. 689 * @param right the object to be copied. 690 * @stable ICU 2.0 691 */ 692 TimeZone& operator=(const TimeZone& right); 693 694 /** 695 * Utility function. For internally loading rule data. 696 * @param top Top resource bundle for tz data 697 * @param ruleid ID of rule to load 698 * @param oldbundle Old bundle to reuse or NULL 699 * @param status Status parameter 700 * @return either a new bundle or *oldbundle 701 * @internal 702 */ 703 static UResourceBundle* loadRule(const UResourceBundle* top, const UnicodeString& ruleid, UResourceBundle* oldbundle, UErrorCode&status); 704 705 private: 706 friend class ZoneMeta; 707 708 709 static TimeZone* createCustomTimeZone(const UnicodeString&); // Creates a time zone based on the string. 710 711 /** 712 * Resolve a link in Olson tzdata. When the given id is known and it's not a link, 713 * the id itself is returned. When the given id is known and it is a link, then 714 * dereferenced zone id is returned. When the given id is unknown, then it returns 715 * empty string. 716 * @param linkTo Input zone id string 717 * @param linkFrom Receives the dereferenced zone id string 718 * @return The reference to the result (linkFrom) 719 */ 720 static UnicodeString& dereferOlsonLink(const UnicodeString& linkTo, UnicodeString& linkFrom); 721 722 /** 723 * Parses the given custom time zone identifier 724 * @param id id A string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or 725 * GMT[+-]hh. 726 * @param sign Receves parsed sign, 1 for positive, -1 for negative. 727 * @param hour Receives parsed hour field 728 * @param minute Receives parsed minute field 729 * @param second Receives parsed second field 730 * @return Returns TRUE when the given custom id is valid. 731 */ 732 static UBool parseCustomID(const UnicodeString& id, int32_t& sign, int32_t& hour, 733 int32_t& min, int32_t& sec); 734 735 /** 736 * Parse a custom time zone identifier and return the normalized 737 * custom time zone identifier for the given custom id string. 738 * @param id a string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or 739 * GMT[+-]hh. 740 * @param normalized Receives the normalized custom ID 741 * @param status Receives the status. When the input ID string is invalid, 742 * U_ILLEGAL_ARGUMENT_ERROR is set. 743 * @return The normalized custom id string. 744 */ 745 static UnicodeString& getCustomID(const UnicodeString& id, UnicodeString& normalized, 746 UErrorCode& status); 747 748 /** 749 * Returns the normalized custome time zone ID for the given offset fields. 750 * @param hour offset hours 751 * @param min offset minutes 752 * @param sec offset seconds 753 * @param netative sign of the offset, TRUE for negative offset. 754 * @param id Receves the format result (normalized custom ID) 755 * @return The reference to id 756 */ 757 static UnicodeString& formatCustomID(int32_t hour, int32_t min, int32_t sec, 758 UBool negative, UnicodeString& id); 759 760 /** 761 * Responsible for setting up DEFAULT_ZONE. Uses routines in TPlatformUtilities 762 * (i.e., platform-specific calls) to get the current system time zone. Failing 763 * that, uses the platform-specific default time zone. Failing that, uses GMT. 764 */ 765 static void initDefault(void); 766 767 // See source file for documentation 768 /** 769 * Lookup the given name in our system zone table. If found, 770 * instantiate a new zone of that name and return it. If not 771 * found, return 0. 772 * @param name tthe given name of a system time zone. 773 * @return the TimeZone indicated by the 'name'. 774 */ 775 static TimeZone* createSystemTimeZone(const UnicodeString& name); 776 777 UnicodeString fID; // this time zone's ID 778 }; 779 780 781 // ------------------------------------- 782 783 inline UnicodeString& 784 TimeZone::getID(UnicodeString& ID) const 785 { 786 ID = fID; 787 return ID; 788 } 789 790 // ------------------------------------- 791 792 inline void 793 TimeZone::setID(const UnicodeString& ID) 794 { 795 fID = ID; 796 } 797 U_NAMESPACE_END 798 799 #endif /* #if !UCONFIG_NO_FORMATTING */ 800 801 #endif //_TIMEZONE 802 //eof 803
