1 /************************************************************************* 2 * Copyright (c) 1997-2011, 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. You can then choose a 71 * supported ID to get a <code>TimeZone</code>. 72 * If the time zone you want is not represented by one of the 73 * supported IDs, then you can create a custom time zone ID with 74 * the following syntax: 75 * 76 * \htmlonly<blockquote>\endhtmlonly 77 * <pre> 78 * GMT[+|-]hh[[:]mm] 79 * </pre> 80 * \htmlonly</blockquote>\endhtmlonly 81 * 82 * For example, you might specify GMT+14:00 as a custom 83 * time zone ID. The <code>TimeZone</code> that is returned 84 * when you specify a custom time zone ID does not include 85 * daylight savings time. 86 * 87 * TimeZone is an abstract class representing a time zone. A TimeZone is needed for 88 * Calendar to produce local time for a particular time zone. A TimeZone comprises 89 * three basic pieces of information: 90 * <ul> 91 * <li>A time zone offset; that, is the number of milliseconds to add or subtract 92 * from a time expressed in terms of GMT to convert it to the same time in that 93 * time zone (without taking daylight savings time into account).</li> 94 * <li>Logic necessary to take daylight savings time into account if daylight savings 95 * time is observed in that time zone (e.g., the days and hours on which daylight 96 * savings time begins and ends).</li> 97 * <li>An ID. This is a text string that uniquely identifies the time zone.</li> 98 * </ul> 99 * 100 * (Only the ID is actually implemented in TimeZone; subclasses of TimeZone may handle 101 * daylight savings time and GMT offset in different ways. Currently we only have one 102 * TimeZone subclass: SimpleTimeZone.) 103 * <P> 104 * The TimeZone class contains a static list containing a TimeZone object for every 105 * combination of GMT offset and daylight-savings time rules currently in use in the 106 * world, each with a unique ID. Each ID consists of a region (usually a continent or 107 * ocean) and a city in that region, separated by a slash, (for example, US Pacific 108 * Time is "America/Los_Angeles.") Because older versions of this class used 109 * three- or four-letter abbreviations instead, there is also a table that maps the older 110 * abbreviations to the newer ones (for example, "PST" maps to "America/Los_Angeles"). 111 * Anywhere the API requires an ID, you can use either form. 112 * <P> 113 * To create a new TimeZone, you call the factory function TimeZone::createTimeZone() 114 * and pass it a time zone ID. You can use the createEnumeration() function to 115 * obtain a list of all the time zone IDs recognized by createTimeZone(). 116 * <P> 117 * You can also use TimeZone::createDefault() to create a TimeZone. This function uses 118 * platform-specific APIs to produce a TimeZone for the time zone corresponding to 119 * the client's computer's physical location. For example, if you're in Japan (assuming 120 * your machine is set up correctly), TimeZone::createDefault() will return a TimeZone 121 * for Japanese Standard Time ("Asia/Tokyo"). 122 */ 123 class U_I18N_API TimeZone : public UObject { 124 public: 125 /** 126 * @stable ICU 2.0 127 */ 128 virtual ~TimeZone(); 129 130 /** 131 * The GMT time zone has a raw offset of zero and does not use daylight 132 * savings time. This is a commonly used time zone. 133 * @return the GMT time zone. 134 * @stable ICU 2.0 135 */ 136 static const TimeZone* U_EXPORT2 getGMT(void); 137 138 /** 139 * Creates a <code>TimeZone</code> for the given ID. 140 * @param ID the ID for a <code>TimeZone</code>, such as "America/Los_Angeles", 141 * or a custom ID such as "GMT-8:00". 142 * @return the specified <code>TimeZone</code>, or the GMT zone with ID 143 * <code>UCAL_UNKNOWN_ZONE_ID</code> ("Etc/Unknown") if the given ID cannot be understood. 144 * Return result guaranteed to be non-null. If you require that the specific zone asked 145 * for be returned, check the ID of the return result. 146 * @stable ICU 2.0 147 */ 148 static TimeZone* U_EXPORT2 createTimeZone(const UnicodeString& ID); 149 150 151 /** 152 * Returns an enumeration over system time zone IDs with the given 153 * filter conditions. 154 * @param zoneType The system time zone type. 155 * @param region The ISO 3166 two-letter country code or UN M.49 156 * three-digit area code. When NULL, no filtering 157 * done by region. 158 * @param rawOffset An offset from GMT in milliseconds, ignoring 159 * the effect of daylight savings time, if any. 160 * When NULL, no filtering done by zone offset. 161 * @param ec Output param to filled in with a success or 162 * an error. 163 * @return an enumeration object, owned by the caller. 164 * @draft ICU 4.8 165 */ 166 static StringEnumeration* U_EXPORT2 createTimeZoneIDEnumeration( 167 USystemTimeZoneType zoneType, 168 const char* region, 169 const int32_t* rawOffset, 170 UErrorCode& ec); 171 172 /** 173 * Returns an enumeration over all recognized time zone IDs. (i.e., 174 * all strings that createTimeZone() accepts) 175 * 176 * @return an enumeration object, owned by the caller. 177 * @stable ICU 2.4 178 */ 179 static StringEnumeration* U_EXPORT2 createEnumeration(); 180 181 /** 182 * Returns an enumeration over time zone IDs with a given raw 183 * offset from GMT. There may be several times zones with the 184 * same GMT offset that differ in the way they handle daylight 185 * savings time. For example, the state of Arizona doesn't 186 * observe daylight savings time. If you ask for the time zone 187 * IDs corresponding to GMT-7:00, you'll get back an enumeration 188 * over two time zone IDs: "America/Denver," which corresponds to 189 * Mountain Standard Time in the winter and Mountain Daylight Time 190 * in the summer, and "America/Phoenix", which corresponds to 191 * Mountain Standard Time year-round, even in the summer. 192 * 193 * @param rawOffset an offset from GMT in milliseconds, ignoring 194 * the effect of daylight savings time, if any 195 * @return an enumeration object, owned by the caller 196 * @stable ICU 2.4 197 */ 198 static StringEnumeration* U_EXPORT2 createEnumeration(int32_t rawOffset); 199 200 /** 201 * Returns an enumeration over time zone IDs associated with the 202 * given country. Some zones are affiliated with no country 203 * (e.g., "UTC"); these may also be retrieved, as a group. 204 * 205 * @param country The ISO 3166 two-letter country code, or NULL to 206 * retrieve zones not affiliated with any country. 207 * @return an enumeration object, owned by the caller 208 * @stable ICU 2.4 209 */ 210 static StringEnumeration* U_EXPORT2 createEnumeration(const char* country); 211 212 /** 213 * Returns the number of IDs in the equivalency group that 214 * includes the given ID. An equivalency group contains zones 215 * that have the same GMT offset and rules. 216 * 217 * <p>The returned count includes the given ID; it is always >= 1. 218 * The given ID must be a system time zone. If it is not, returns 219 * zero. 220 * @param id a system time zone ID 221 * @return the number of zones in the equivalency group containing 222 * 'id', or zero if 'id' is not a valid system ID 223 * @see #getEquivalentID 224 * @stable ICU 2.0 225 */ 226 static int32_t U_EXPORT2 countEquivalentIDs(const UnicodeString& id); 227 228 /** 229 * Returns an ID in the equivalency group that 230 * includes the given ID. An equivalency group contains zones 231 * that have the same GMT offset and rules. 232 * 233 * <p>The given index must be in the range 0..n-1, where n is the 234 * value returned by <code>countEquivalentIDs(id)</code>. For 235 * some value of 'index', the returned value will be equal to the 236 * given id. If the given id is not a valid system time zone, or 237 * if 'index' is out of range, then returns an empty string. 238 * @param id a system time zone ID 239 * @param index a value from 0 to n-1, where n is the value 240 * returned by <code>countEquivalentIDs(id)</code> 241 * @return the ID of the index-th zone in the equivalency group 242 * containing 'id', or an empty string if 'id' is not a valid 243 * system ID or 'index' is out of range 244 * @see #countEquivalentIDs 245 * @stable ICU 2.0 246 */ 247 static const UnicodeString U_EXPORT2 getEquivalentID(const UnicodeString& id, 248 int32_t index); 249 250 /** 251 * Creates a new copy of the default TimeZone for this host. Unless the default time 252 * zone has already been set using adoptDefault() or setDefault(), the default is 253 * determined by querying the system using methods in TPlatformUtilities. If the 254 * system routines fail, or if they specify a TimeZone or TimeZone offset which is not 255 * recognized, the TimeZone indicated by the ID kLastResortID is instantiated 256 * and made the default. 257 * 258 * @return A default TimeZone. Clients are responsible for deleting the time zone 259 * object returned. 260 * @stable ICU 2.0 261 */ 262 static TimeZone* U_EXPORT2 createDefault(void); 263 264 /** 265 * Sets the default time zone (i.e., what's returned by createDefault()) to be the 266 * specified time zone. If NULL is specified for the time zone, the default time 267 * zone is set to the default host time zone. This call adopts the TimeZone object 268 * passed in; the clent is no longer responsible for deleting it. 269 * 270 * @param zone A pointer to the new TimeZone object to use as the default. 271 * @stable ICU 2.0 272 */ 273 static void U_EXPORT2 adoptDefault(TimeZone* zone); 274 275 /** 276 * Same as adoptDefault(), except that the TimeZone object passed in is NOT adopted; 277 * the caller remains responsible for deleting it. 278 * 279 * @param zone The given timezone. 280 * @system 281 */ 282 static void U_EXPORT2 setDefault(const TimeZone& zone); 283 284 /** 285 * Returns the timezone data version currently used by ICU. 286 * @param status Output param to filled in with a success or an error. 287 * @return the version string, such as "2007f" 288 * @stable ICU 3.8 289 */ 290 static const char* U_EXPORT2 getTZDataVersion(UErrorCode& status); 291 292 /** 293 * Returns the canonical system timezone ID or the normalized 294 * custom time zone ID for the given time zone ID. 295 * @param id The input time zone ID to be canonicalized. 296 * @param canonicalID Receives the canonical system time zone ID 297 * or the custom time zone ID in normalized format. 298 * @param status Recevies the status. When the given time zone ID 299 * is neither a known system time zone ID nor a 300 * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR 301 * is set. 302 * @return A reference to the result. 303 * @stable ICU 4.0 304 */ 305 static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, 306 UnicodeString& canonicalID, UErrorCode& status); 307 308 /** 309 * Returns the canonical system time zone ID or the normalized 310 * custom time zone ID for the given time zone ID. 311 * @param id The input time zone ID to be canonicalized. 312 * @param canonicalID Receives the canonical system time zone ID 313 * or the custom time zone ID in normalized format. 314 * @param isSystemID Receives if the given ID is a known system 315 * time zone ID. 316 * @param status Recevies the status. When the given time zone ID 317 * is neither a known system time zone ID nor a 318 * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR 319 * is set. 320 * @return A reference to the result. 321 * @stable ICU 4.0 322 */ 323 static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, 324 UnicodeString& canonicalID, UBool& isSystemID, UErrorCode& status); 325 326 /** 327 * Returns true if the two TimeZones are equal. (The TimeZone version only compares 328 * IDs, but subclasses are expected to also compare the fields they add.) 329 * 330 * @param that The TimeZone object to be compared with. 331 * @return True if the given TimeZone is equal to this TimeZone; false 332 * otherwise. 333 * @stable ICU 2.0 334 */ 335 virtual UBool operator==(const TimeZone& that) const; 336 337 /** 338 * Returns true if the two TimeZones are NOT equal; that is, if operator==() returns 339 * false. 340 * 341 * @param that The TimeZone object to be compared with. 342 * @return True if the given TimeZone is not equal to this TimeZone; false 343 * otherwise. 344 * @stable ICU 2.0 345 */ 346 UBool operator!=(const TimeZone& that) const {return !operator==(that);} 347 348 /** 349 * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add 350 * to GMT to get local time in this time zone, taking daylight savings time into 351 * account) as of a particular reference date. The reference date is used to determine 352 * whether daylight savings time is in effect and needs to be figured into the offset 353 * that is returned (in other words, what is the adjusted GMT offset in this time zone 354 * at this particular date and time?). For the time zones produced by createTimeZone(), 355 * the reference data is specified according to the Gregorian calendar, and the date 356 * and time fields are local standard time. 357 * 358 * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, 359 * which returns both the raw and the DST offset for a given time. This method 360 * is retained only for backward compatibility. 361 * 362 * @param era The reference date's era 363 * @param year The reference date's year 364 * @param month The reference date's month (0-based; 0 is January) 365 * @param day The reference date's day-in-month (1-based) 366 * @param dayOfWeek The reference date's day-of-week (1-based; 1 is Sunday) 367 * @param millis The reference date's milliseconds in day, local standard time 368 * @param status Output param to filled in with a success or an error. 369 * @return The offset in milliseconds to add to GMT to get local time. 370 * @stable ICU 2.0 371 */ 372 virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, 373 uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const = 0; 374 375 /** 376 * Gets the time zone offset, for current date, modified in case of 377 * daylight savings. This is the offset to add *to* UTC to get local time. 378 * 379 * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, 380 * which returns both the raw and the DST offset for a given time. This method 381 * is retained only for backward compatibility. 382 * 383 * @param era the era of the given date. 384 * @param year the year in the given date. 385 * @param month the month in the given date. 386 * Month is 0-based. e.g., 0 for January. 387 * @param day the day-in-month of the given date. 388 * @param dayOfWeek the day-of-week of the given date. 389 * @param milliseconds the millis in day in <em>standard</em> local time. 390 * @param monthLength the length of the given month in days. 391 * @param status Output param to filled in with a success or an error. 392 * @return the offset to add *to* GMT to get local time. 393 * @stable ICU 2.0 394 */ 395 virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, 396 uint8_t dayOfWeek, int32_t milliseconds, 397 int32_t monthLength, UErrorCode& status) const = 0; 398 399 /** 400 * Returns the time zone raw and GMT offset for the given moment 401 * in time. Upon return, local-millis = GMT-millis + rawOffset + 402 * dstOffset. All computations are performed in the proleptic 403 * Gregorian calendar. The default implementation in the TimeZone 404 * class delegates to the 8-argument getOffset(). 405 * 406 * @param date moment in time for which to return offsets, in 407 * units of milliseconds from January 1, 1970 0:00 GMT, either GMT 408 * time or local wall time, depending on `local'. 409 * @param local if true, `date' is local wall time; otherwise it 410 * is in GMT time. 411 * @param rawOffset output parameter to receive the raw offset, that 412 * is, the offset not including DST adjustments 413 * @param dstOffset output parameter to receive the DST offset, 414 * that is, the offset to be added to `rawOffset' to obtain the 415 * total offset between local and GMT time. If DST is not in 416 * effect, this value is zero; otherwise it is a positive value, 417 * typically one hour. 418 * @param ec input-output error code 419 * 420 * @stable ICU 2.8 421 */ 422 virtual void getOffset(UDate date, UBool local, int32_t& rawOffset, 423 int32_t& dstOffset, UErrorCode& ec) const; 424 425 /** 426 * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add 427 * to GMT to get local time, before taking daylight savings time into account). 428 * 429 * @param offsetMillis The new raw GMT offset for this time zone. 430 * @stable ICU 2.0 431 */ 432 virtual void setRawOffset(int32_t offsetMillis) = 0; 433 434 /** 435 * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add 436 * to GMT to get local time, before taking daylight savings time into account). 437 * 438 * @return The TimeZone's raw GMT offset. 439 * @stable ICU 2.0 440 */ 441 virtual int32_t getRawOffset(void) const = 0; 442 443 /** 444 * Fills in "ID" with the TimeZone's ID. 445 * 446 * @param ID Receives this TimeZone's ID. 447 * @return A reference to 'ID' 448 * @stable ICU 2.0 449 */ 450 UnicodeString& getID(UnicodeString& ID) const; 451 452 /** 453 * Sets the TimeZone's ID to the specified value. This doesn't affect any other 454 * fields (for example, if you say< 455 * blockquote><pre> 456 * . TimeZone* foo = TimeZone::createTimeZone("America/New_York"); 457 * . foo.setID("America/Los_Angeles"); 458 * </pre>\htmlonly</blockquote>\endhtmlonly 459 * the time zone's GMT offset and daylight-savings rules don't change to those for 460 * Los Angeles. They're still those for New York. Only the ID has changed.) 461 * 462 * @param ID The new time zone ID. 463 * @stable ICU 2.0 464 */ 465 void setID(const UnicodeString& ID); 466 467 /** 468 * Enum for use with getDisplayName 469 * @stable ICU 2.4 470 */ 471 enum EDisplayType { 472 /** 473 * Selector for short display name 474 * @stable ICU 2.4 475 */ 476 SHORT = 1, 477 /** 478 * Selector for long display name 479 * @stable ICU 2.4 480 */ 481 LONG, 482 /** 483 * Selector for short generic display name 484 * @stable ICU 4.4 485 */ 486 SHORT_GENERIC, 487 /** 488 * Selector for long generic display name 489 * @stable ICU 4.4 490 */ 491 LONG_GENERIC, 492 /** 493 * Selector for short display name derived 494 * from time zone offset 495 * @stable ICU 4.4 496 */ 497 SHORT_GMT, 498 /** 499 * Selector for long display name derived 500 * from time zone offset 501 * @stable ICU 4.4 502 */ 503 LONG_GMT, 504 /** 505 * Selector for short display name derived 506 * from the time zone's fallback name 507 * @stable ICU 4.4 508 */ 509 SHORT_COMMONLY_USED, 510 /** 511 * Selector for long display name derived 512 * from the time zone's fallback name 513 * @stable ICU 4.4 514 */ 515 GENERIC_LOCATION 516 }; 517 518 /** 519 * Returns a name of this time zone suitable for presentation to the user 520 * in the default locale. 521 * This method returns the long name, not including daylight savings. 522 * If the display name is not available for the locale, 523 * then this method returns a string in the format 524 * <code>GMT[+-]hh:mm</code>. 525 * @param result the human-readable name of this time zone in the default locale. 526 * @return A reference to 'result'. 527 * @stable ICU 2.0 528 */ 529 UnicodeString& getDisplayName(UnicodeString& result) const; 530 531 /** 532 * Returns a name of this time zone suitable for presentation to the user 533 * in the specified locale. 534 * This method returns the long name, not including daylight savings. 535 * If the display name is not available for the locale, 536 * then this method returns a string in the format 537 * <code>GMT[+-]hh:mm</code>. 538 * @param locale the locale in which to supply the display name. 539 * @param result the human-readable name of this time zone in the given locale 540 * or in the default locale if the given locale is not recognized. 541 * @return A reference to 'result'. 542 * @stable ICU 2.0 543 */ 544 UnicodeString& getDisplayName(const Locale& locale, UnicodeString& result) const; 545 546 /** 547 * Returns a name of this time zone suitable for presentation to the user 548 * in the default locale. 549 * If the display name is not available for the locale, 550 * then this method returns a string in the format 551 * <code>GMT[+-]hh:mm</code>. 552 * @param daylight if true, return the daylight savings name. 553 * @param style 554 * @param result the human-readable name of this time zone in the default locale. 555 * @return A reference to 'result'. 556 * @stable ICU 2.0 557 */ 558 UnicodeString& getDisplayName(UBool daylight, EDisplayType style, UnicodeString& result) const; 559 560 /** 561 * Returns a name of this time zone suitable for presentation to the user 562 * in the specified locale. 563 * If the display name is not available for the locale, 564 * then this method returns a string in the format 565 * <code>GMT[+-]hh:mm</code>. 566 * @param daylight if true, return the daylight savings name. 567 * @param style 568 * @param locale the locale in which to supply the display name. 569 * @param result the human-readable name of this time zone in the given locale 570 * or in the default locale if the given locale is not recognized. 571 * @return A refence to 'result'. 572 * @stable ICU 2.0 573 */ 574 UnicodeString& getDisplayName(UBool daylight, EDisplayType style, const Locale& locale, UnicodeString& result) const; 575 576 /** 577 * Queries if this time zone uses daylight savings time. 578 * @return true if this time zone uses daylight savings time, 579 * false, otherwise. 580 * <p><strong>Note:</strong>The default implementation of 581 * ICU TimeZone uses the tz database, which supports historic 582 * rule changes, for system time zones. With the implementation, 583 * there are time zones that used daylight savings time in the 584 * past, but no longer used currently. For example, Asia/Tokyo has 585 * never used daylight savings time since 1951. Most clients would 586 * expect that this method to return <code>FALSE</code> for such case. 587 * The default implementation of this method returns <code>TRUE</code> 588 * when the time zone uses daylight savings time in the current 589 * (Gregorian) calendar year. 590 * @stable ICU 2.0 591 */ 592 virtual UBool useDaylightTime(void) const = 0; 593 594 /** 595 * Queries if the given date is in daylight savings time in 596 * this time zone. 597 * This method is wasteful since it creates a new GregorianCalendar and 598 * deletes it each time it is called. This is a deprecated method 599 * and provided only for Java compatibility. 600 * 601 * @param date the given UDate. 602 * @param status Output param filled in with success/error code. 603 * @return true if the given date is in daylight savings time, 604 * false, otherwise. 605 * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead. 606 */ 607 virtual UBool inDaylightTime(UDate date, UErrorCode& status) const = 0; 608 609 /** 610 * Returns true if this zone has the same rule and offset as another zone. 611 * That is, if this zone differs only in ID, if at all. 612 * @param other the <code>TimeZone</code> object to be compared with 613 * @return true if the given zone is the same as this one, 614 * with the possible exception of the ID 615 * @stable ICU 2.0 616 */ 617 virtual UBool hasSameRules(const TimeZone& other) const; 618 619 /** 620 * Clones TimeZone objects polymorphically. Clients are responsible for deleting 621 * the TimeZone object cloned. 622 * 623 * @return A new copy of this TimeZone object. 624 * @stable ICU 2.0 625 */ 626 virtual TimeZone* clone(void) const = 0; 627 628 /** 629 * Return the class ID for this class. This is useful only for 630 * comparing to a return value from getDynamicClassID(). 631 * @return The class ID for all objects of this class. 632 * @stable ICU 2.0 633 */ 634 static UClassID U_EXPORT2 getStaticClassID(void); 635 636 /** 637 * Returns a unique class ID POLYMORPHICALLY. This method is to 638 * implement a simple version of RTTI, since not all C++ compilers support genuine 639 * RTTI. Polymorphic operator==() and clone() methods call this method. 640 * <P> 641 * Concrete subclasses of TimeZone must use the UOBJECT_DEFINE_RTTI_IMPLEMENTATION 642 * macro from uobject.h in their implementation to provide correct RTTI information. 643 * @return The class ID for this object. All objects of a given class have the 644 * same class ID. Objects of other classes have different class IDs. 645 * @stable ICU 2.0 646 */ 647 virtual UClassID getDynamicClassID(void) const = 0; 648 649 /** 650 * Returns the amount of time to be added to local standard time 651 * to get local wall clock time. 652 * <p> 653 * The default implementation always returns 3600000 milliseconds 654 * (i.e., one hour) if this time zone observes Daylight Saving 655 * Time. Otherwise, 0 (zero) is returned. 656 * <p> 657 * If an underlying TimeZone implementation subclass supports 658 * historical Daylight Saving Time changes, this method returns 659 * the known latest daylight saving value. 660 * 661 * @return the amount of saving time in milliseconds 662 * @stable ICU 3.6 663 */ 664 virtual int32_t getDSTSavings() const; 665 666 /** 667 * Gets the region code associated with the given 668 * system time zone ID. The region code is either ISO 3166 669 * 2-letter country code or UN M.49 3-digit area code. 670 * When the time zone is not associated with a specific location, 671 * for example - "Etc/UTC", "EST5EDT", then this method returns 672 * "001" (UN M.49 area code for World). 673 * 674 * @param id The system time zone ID. 675 * @param region Output buffer for receiving the region code. 676 * @param capacity The size of the output buffer. 677 * @param status Receives the status. When the given time zone ID 678 * is not a known system time zone ID, 679 * U_ILLEGAL_ARGUMENT_ERROR is set. 680 * @return The length of the output region code. 681 * @draft ICU 4.8 682 */ 683 static int32_t U_EXPORT2 getRegion(const UnicodeString& id, 684 char *region, int32_t capacity, UErrorCode& status); 685 686 protected: 687 688 /** 689 * Default constructor. ID is initialized to the empty string. 690 * @stable ICU 2.0 691 */ 692 TimeZone(); 693 694 /** 695 * Construct a TimeZone with a given ID. 696 * @param id a system time zone ID 697 * @stable ICU 2.0 698 */ 699 TimeZone(const UnicodeString &id); 700 701 /** 702 * Copy constructor. 703 * @param source the object to be copied. 704 * @stable ICU 2.0 705 */ 706 TimeZone(const TimeZone& source); 707 708 /** 709 * Default assignment operator. 710 * @param right the object to be copied. 711 * @stable ICU 2.0 712 */ 713 TimeZone& operator=(const TimeZone& right); 714 715 /** 716 * Utility function. For internally loading rule data. 717 * @param top Top resource bundle for tz data 718 * @param ruleid ID of rule to load 719 * @param oldbundle Old bundle to reuse or NULL 720 * @param status Status parameter 721 * @return either a new bundle or *oldbundle 722 * @internal 723 */ 724 static UResourceBundle* loadRule(const UResourceBundle* top, const UnicodeString& ruleid, UResourceBundle* oldbundle, UErrorCode&status); 725 726 727 private: 728 friend class ZoneMeta; 729 730 731 static TimeZone* createCustomTimeZone(const UnicodeString&); // Creates a time zone based on the string. 732 733 /** 734 * Finds the given ID in the Olson tzdata. If the given ID is found in the tzdata, 735 * returns the pointer to the ID resource. This method is exposed through ZoneMeta class 736 * for ICU internal implementation and useful for building hashtable using a time zone 737 * ID as a key. 738 * @param id zone id string 739 * @return the pointer of the ID resource, or NULL. 740 */ 741 static const UChar* findID(const UnicodeString& id); 742 743 /** 744 * Resolve a link in Olson tzdata. When the given id is known and it's not a link, 745 * the id itself is returned. When the given id is known and it is a link, then 746 * dereferenced zone id is returned. When the given id is unknown, then it returns 747 * NULL. 748 * @param id zone id string 749 * @return the dereferenced zone or NULL 750 */ 751 static const UChar* dereferOlsonLink(const UnicodeString& id); 752 753 /** 754 * Returns the region code associated with the given zone, 755 * or NULL if the zone is not known. 756 * @param id zone id string 757 * @return the region associated with the given zone 758 */ 759 static const UChar* getRegion(const UnicodeString& id); 760 761 /** 762 * Returns the region code associated with the given zone, 763 * or NULL if the zone is not known. 764 * @param id zone id string 765 * @param status Status parameter 766 * @return the region associated with the given zone 767 */ 768 static const UChar* getRegion(const UnicodeString& id, UErrorCode& status); 769 770 /** 771 * Parses the given custom time zone identifier 772 * @param id id A string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or 773 * GMT[+-]hh. 774 * @param sign Receves parsed sign, 1 for positive, -1 for negative. 775 * @param hour Receives parsed hour field 776 * @param minute Receives parsed minute field 777 * @param second Receives parsed second field 778 * @return Returns TRUE when the given custom id is valid. 779 */ 780 static UBool parseCustomID(const UnicodeString& id, int32_t& sign, int32_t& hour, 781 int32_t& minute, int32_t& second); 782 783 /** 784 * Parse a custom time zone identifier and return the normalized 785 * custom time zone identifier for the given custom id string. 786 * @param id a string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or 787 * GMT[+-]hh. 788 * @param normalized Receives the normalized custom ID 789 * @param status Receives the status. When the input ID string is invalid, 790 * U_ILLEGAL_ARGUMENT_ERROR is set. 791 * @return The normalized custom id string. 792 */ 793 static UnicodeString& getCustomID(const UnicodeString& id, UnicodeString& normalized, 794 UErrorCode& status); 795 796 /** 797 * Returns the normalized custome time zone ID for the given offset fields. 798 * @param hour offset hours 799 * @param min offset minutes 800 * @param sec offset seconds 801 * @param negative sign of the offset, TRUE for negative offset. 802 * @param id Receves the format result (normalized custom ID) 803 * @return The reference to id 804 */ 805 static UnicodeString& formatCustomID(int32_t hour, int32_t min, int32_t sec, 806 UBool negative, UnicodeString& id); 807 808 /** 809 * Responsible for setting up DEFAULT_ZONE. Uses routines in TPlatformUtilities 810 * (i.e., platform-specific calls) to get the current system time zone. Failing 811 * that, uses the platform-specific default time zone. Failing that, uses GMT. 812 */ 813 static void initDefault(void); 814 815 // See source file for documentation 816 /** 817 * Lookup the given name in our system zone table. If found, 818 * instantiate a new zone of that name and return it. If not 819 * found, return 0. 820 * @param name tthe given name of a system time zone. 821 * @return the TimeZone indicated by the 'name'. 822 */ 823 static TimeZone* createSystemTimeZone(const UnicodeString& name); 824 static TimeZone* createSystemTimeZone(const UnicodeString& name, UErrorCode& ec); 825 826 UnicodeString fID; // this time zone's ID 827 828 friend class TZEnumeration; 829 }; 830 831 832 // ------------------------------------- 833 834 inline UnicodeString& 835 TimeZone::getID(UnicodeString& ID) const 836 { 837 ID = fID; 838 return ID; 839 } 840 841 // ------------------------------------- 842 843 inline void 844 TimeZone::setID(const UnicodeString& ID) 845 { 846 fID = ID; 847 } 848 U_NAMESPACE_END 849 850 #endif /* #if !UCONFIG_NO_FORMATTING */ 851 852 #endif //_TIMEZONE 853 //eof 854
