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diff --git a/intl/icu/source/i18n/unicode/timezone.h b/intl/icu/source/i18n/unicode/timezone.h new file mode 100644 index 0000000000..a2c0552c18 --- /dev/null +++ b/intl/icu/source/i18n/unicode/timezone.h @@ -0,0 +1,1038 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/************************************************************************* +* Copyright (c) 1997-2016, International Business Machines Corporation +* and others. All Rights Reserved. +************************************************************************** +* +* File TIMEZONE.H +* +* Modification History: +* +* Date Name Description +* 04/21/97 aliu Overhauled header. +* 07/09/97 helena Changed createInstance to createDefault. +* 08/06/97 aliu Removed dependency on internal header for Hashtable. +* 08/10/98 stephen Changed getDisplayName() API conventions to match +* 08/19/98 stephen Changed createTimeZone() to never return 0 +* 09/02/98 stephen Sync to JDK 1.2 8/31 +* - Added getOffset(... monthlen ...) +* - Added hasSameRules() +* 09/15/98 stephen Added getStaticClassID +* 12/03/99 aliu Moved data out of static table into icudata.dll. +* Hashtable replaced by new static data structures. +* 12/14/99 aliu Made GMT public. +* 08/15/01 grhoten Made GMT private and added the getGMT() function +************************************************************************** +*/ + +#ifndef TIMEZONE_H +#define TIMEZONE_H + +#include "unicode/utypes.h" + +#if U_SHOW_CPLUSPLUS_API + +/** + * \file + * \brief C++ API: TimeZone object + */ + +#if !UCONFIG_NO_FORMATTING + +#include "unicode/uobject.h" +#include "unicode/unistr.h" +#include "unicode/ures.h" +#include "unicode/ucal.h" + +U_NAMESPACE_BEGIN + +class StringEnumeration; + +/** + * + * <code>TimeZone</code> represents a time zone offset, and also figures out daylight + * savings. + * + * <p> + * Typically, you get a <code>TimeZone</code> using <code>createDefault</code> + * which creates a <code>TimeZone</code> based on the time zone where the program + * is running. For example, for a program running in Japan, <code>createDefault</code> + * creates a <code>TimeZone</code> object based on Japanese Standard Time. + * + * <p> + * You can also get a <code>TimeZone</code> using <code>createTimeZone</code> along + * with a time zone ID. For instance, the time zone ID for the US Pacific + * Time zone is "America/Los_Angeles". So, you can get a Pacific Time <code>TimeZone</code> object + * with: + * \htmlonly<blockquote>\endhtmlonly + * <pre> + * TimeZone *tz = TimeZone::createTimeZone("America/Los_Angeles"); + * </pre> + * \htmlonly</blockquote>\endhtmlonly + * You can use the <code>createEnumeration</code> method to iterate through + * all the supported time zone IDs, or the <code>getCanonicalID</code> method to check + * if a time zone ID is supported or not. You can then choose a + * supported ID to get a <code>TimeZone</code>. + * If the time zone you want is not represented by one of the + * supported IDs, then you can create a custom time zone ID with + * the following syntax: + * + * \htmlonly<blockquote>\endhtmlonly + * <pre> + * GMT[+|-]hh[[:]mm] + * </pre> + * \htmlonly</blockquote>\endhtmlonly + * + * For example, you might specify GMT+14:00 as a custom + * time zone ID. The <code>TimeZone</code> that is returned + * when you specify a custom time zone ID uses the specified + * offset from GMT(=UTC) and does not observe daylight saving + * time. For example, you might specify GMT+14:00 as a custom + * time zone ID to create a TimeZone representing 14 hours ahead + * of GMT (with no daylight saving time). In addition, + * <code>getCanonicalID</code> can also be used to + * normalize a custom time zone ID. + * + * TimeZone is an abstract class representing a time zone. A TimeZone is needed for + * Calendar to produce local time for a particular time zone. A TimeZone comprises + * three basic pieces of information: + * <ul> + * <li>A time zone offset; that, is the number of milliseconds to add or subtract + * from a time expressed in terms of GMT to convert it to the same time in that + * time zone (without taking daylight savings time into account).</li> + * <li>Logic necessary to take daylight savings time into account if daylight savings + * time is observed in that time zone (e.g., the days and hours on which daylight + * savings time begins and ends).</li> + * <li>An ID. This is a text string that uniquely identifies the time zone.</li> + * </ul> + * + * (Only the ID is actually implemented in TimeZone; subclasses of TimeZone may handle + * daylight savings time and GMT offset in different ways. Currently we have the following + * TimeZone subclasses: RuleBasedTimeZone, SimpleTimeZone, and VTimeZone.) + * <P> + * The TimeZone class contains a static list containing a TimeZone object for every + * combination of GMT offset and daylight-savings time rules currently in use in the + * world, each with a unique ID. Each ID consists of a region (usually a continent or + * ocean) and a city in that region, separated by a slash, (for example, US Pacific + * Time is "America/Los_Angeles.") Because older versions of this class used + * three- or four-letter abbreviations instead, there is also a table that maps the older + * abbreviations to the newer ones (for example, "PST" maps to "America/Los_Angeles"). + * Anywhere the API requires an ID, you can use either form. + * <P> + * To create a new TimeZone, you call the factory function TimeZone::createTimeZone() + * and pass it a time zone ID. You can use the createEnumeration() function to + * obtain a list of all the time zone IDs recognized by createTimeZone(). + * <P> + * You can also use TimeZone::createDefault() to create a TimeZone. This function uses + * platform-specific APIs to produce a TimeZone for the time zone corresponding to + * the client's computer's physical location. For example, if you're in Japan (assuming + * your machine is set up correctly), TimeZone::createDefault() will return a TimeZone + * for Japanese Standard Time ("Asia/Tokyo"). + */ +class U_I18N_API TimeZone : public UObject { +public: + /** + * @stable ICU 2.0 + */ + virtual ~TimeZone(); + + /** + * Returns the "unknown" time zone. + * It behaves like the GMT/UTC time zone but has the + * <code>UCAL_UNKNOWN_ZONE_ID</code> = "Etc/Unknown". + * createTimeZone() returns a mutable clone of this time zone if the input ID is not recognized. + * + * @return the "unknown" time zone. + * @see UCAL_UNKNOWN_ZONE_ID + * @see createTimeZone + * @see getGMT + * @stable ICU 49 + */ + static const TimeZone& U_EXPORT2 getUnknown(); + + /** + * The GMT (=UTC) time zone has a raw offset of zero and does not use daylight + * savings time. This is a commonly used time zone. + * + * <p>Note: For backward compatibility reason, the ID used by the time + * zone returned by this method is "GMT", although the ICU's canonical + * ID for the GMT time zone is "Etc/GMT". + * + * @return the GMT/UTC time zone. + * @see getUnknown + * @stable ICU 2.0 + */ + static const TimeZone* U_EXPORT2 getGMT(void); + + /** + * Creates a <code>TimeZone</code> for the given ID. + * @param ID the ID for a <code>TimeZone</code>, such as "America/Los_Angeles", + * or a custom ID such as "GMT-8:00". + * @return the specified <code>TimeZone</code>, or a mutable clone of getUnknown() + * if the given ID cannot be understood or if the given ID is "Etc/Unknown". + * The return result is guaranteed to be non-nullptr. + * If you require that the specific zone asked for be returned, + * compare the result with getUnknown() or check the ID of the return result. + * @stable ICU 2.0 + */ + static TimeZone* U_EXPORT2 createTimeZone(const UnicodeString& ID); + + /** + * Returns an enumeration over system time zone IDs with the given + * filter conditions. + * @param zoneType The system time zone type. + * @param region The ISO 3166 two-letter country code or UN M.49 + * three-digit area code. When nullptr, no filtering + * done by region. + * @param rawOffset An offset from GMT in milliseconds, ignoring + * the effect of daylight savings time, if any. + * When nullptr, no filtering done by zone offset. + * @param ec Output param to filled in with a success or + * an error. + * @return an enumeration object, owned by the caller. + * @stable ICU 4.8 + */ + static StringEnumeration* U_EXPORT2 createTimeZoneIDEnumeration( + USystemTimeZoneType zoneType, + const char* region, + const int32_t* rawOffset, + UErrorCode& ec); + +#ifndef U_HIDE_DEPRECATED_API + /** + * Returns an enumeration over all recognized time zone IDs. (i.e., + * all strings that createTimeZone() accepts) + * + * @return an enumeration object, owned by the caller. + * @deprecated ICU 70 Use createEnumeration(UErrorCode&) instead. + */ + static StringEnumeration* U_EXPORT2 createEnumeration(); +#endif // U_HIDE_DEPRECATED_API + + /** + * Returns an enumeration over all recognized time zone IDs. (i.e., + * all strings that createTimeZone() accepts) + * + * @param status Receives the status. + * @return an enumeration object, owned by the caller. + * @stable ICU 70 + */ + static StringEnumeration* U_EXPORT2 createEnumeration(UErrorCode& status); + +#ifndef U_HIDE_DEPRECATED_API + /** + * Returns an enumeration over time zone IDs with a given raw + * offset from GMT. There may be several times zones with the + * same GMT offset that differ in the way they handle daylight + * savings time. For example, the state of Arizona doesn't + * observe daylight savings time. If you ask for the time zone + * IDs corresponding to GMT-7:00, you'll get back an enumeration + * over two time zone IDs: "America/Denver," which corresponds to + * Mountain Standard Time in the winter and Mountain Daylight Time + * in the summer, and "America/Phoenix", which corresponds to + * Mountain Standard Time year-round, even in the summer. + * + * @param rawOffset an offset from GMT in milliseconds, ignoring + * the effect of daylight savings time, if any + * @return an enumeration object, owned by the caller + * @deprecated ICU 70 Use createEnumerationForRawOffset(int32_t,UErrorCode&) instead. + */ + static StringEnumeration* U_EXPORT2 createEnumeration(int32_t rawOffset); +#endif // U_HIDE_DEPRECATED_API + + /** + * Returns an enumeration over time zone IDs with a given raw + * offset from GMT. There may be several times zones with the + * same GMT offset that differ in the way they handle daylight + * savings time. For example, the state of Arizona doesn't + * observe daylight savings time. If you ask for the time zone + * IDs corresponding to GMT-7:00, you'll get back an enumeration + * over two time zone IDs: "America/Denver," which corresponds to + * Mountain Standard Time in the winter and Mountain Daylight Time + * in the summer, and "America/Phoenix", which corresponds to + * Mountain Standard Time year-round, even in the summer. + * + * @param rawOffset an offset from GMT in milliseconds, ignoring + * the effect of daylight savings time, if any + * @param status Receives the status. + * @return an enumeration object, owned by the caller + * @stable ICU 70 + */ + static StringEnumeration* U_EXPORT2 createEnumerationForRawOffset(int32_t rawOffset, UErrorCode& status); + +#ifndef U_HIDE_DEPRECATED_API + /** + * Returns an enumeration over time zone IDs associated with the + * given region. Some zones are affiliated with no region + * (e.g., "UTC"); these may also be retrieved, as a group. + * + * @param region The ISO 3166 two-letter country code, or nullptr to + * retrieve zones not affiliated with any region. + * @return an enumeration object, owned by the caller + * @deprecated ICU 70 Use createEnumerationForRegion(const char*,UErrorCode&) instead. + */ + static StringEnumeration* U_EXPORT2 createEnumeration(const char* region); +#endif // U_HIDE_DEPRECATED_API + + /** + * Returns an enumeration over time zone IDs associated with the + * given region. Some zones are affiliated with no region + * (e.g., "UTC"); these may also be retrieved, as a group. + * + * @param region The ISO 3166 two-letter country code, or nullptr to + * retrieve zones not affiliated with any region. + * @param status Receives the status. + * @return an enumeration object, owned by the caller + * @stable ICU 70 + */ + static StringEnumeration* U_EXPORT2 createEnumerationForRegion(const char* region, UErrorCode& status); + + /** + * Returns the number of IDs in the equivalency group that + * includes the given ID. An equivalency group contains zones + * that have the same GMT offset and rules. + * + * <p>The returned count includes the given ID; it is always >= 1. + * The given ID must be a system time zone. If it is not, returns + * zero. + * @param id a system time zone ID + * @return the number of zones in the equivalency group containing + * 'id', or zero if 'id' is not a valid system ID + * @see #getEquivalentID + * @stable ICU 2.0 + */ + static int32_t U_EXPORT2 countEquivalentIDs(const UnicodeString& id); + + /** + * Returns an ID in the equivalency group that + * includes the given ID. An equivalency group contains zones + * that have the same GMT offset and rules. + * + * <p>The given index must be in the range 0..n-1, where n is the + * value returned by <code>countEquivalentIDs(id)</code>. For + * some value of 'index', the returned value will be equal to the + * given id. If the given id is not a valid system time zone, or + * if 'index' is out of range, then returns an empty string. + * @param id a system time zone ID + * @param index a value from 0 to n-1, where n is the value + * returned by <code>countEquivalentIDs(id)</code> + * @return the ID of the index-th zone in the equivalency group + * containing 'id', or an empty string if 'id' is not a valid + * system ID or 'index' is out of range + * @see #countEquivalentIDs + * @stable ICU 2.0 + */ + static const UnicodeString U_EXPORT2 getEquivalentID(const UnicodeString& id, + int32_t index); + + /** + * Creates an instance of TimeZone detected from the current host + * system configuration. If the host system detection routines fail, + * or if they specify a TimeZone or TimeZone offset which is not + * recognized, then the special TimeZone "Etc/Unknown" is returned. + * + * Note that ICU4C does not change the default time zone unless + * `TimeZone::adoptDefault(TimeZone*)` or + * `TimeZone::setDefault(const TimeZone&)` is explicitly called by a + * user. This method does not update the current ICU's default, + * and may return a different TimeZone from the one returned by + * `TimeZone::createDefault()`. + * + * <p>This function is not thread safe.</p> + * + * @return A new instance of TimeZone detected from the current host system + * configuration. + * @see adoptDefault + * @see setDefault + * @see createDefault + * @see getUnknown + * @stable ICU 55 + */ + static TimeZone* U_EXPORT2 detectHostTimeZone(); + + /** + * Creates a new copy of the default TimeZone for this host. Unless the default time + * zone has already been set using adoptDefault() or setDefault(), the default is + * determined by querying the host system configuration. If the host system detection + * routines fail, or if they specify a TimeZone or TimeZone offset which is not + * recognized, then the special TimeZone "Etc/Unknown" is instantiated and made the + * default. + * + * @return A default TimeZone. Clients are responsible for deleting the time zone + * object returned. + * @see getUnknown + * @stable ICU 2.0 + */ + static TimeZone* U_EXPORT2 createDefault(void); + +#ifndef U_HIDE_INTERNAL_API + /** + * If the locale contains the timezone keyword, creates a copy of that TimeZone. + * Otherwise, create the default timezone. + * + * @param locale a locale which may contains 'timezone' keyword/value. + * @return A TimeZone. Clients are responsible for deleting the time zone + * object returned. + * @internal + */ + static TimeZone* U_EXPORT2 forLocaleOrDefault(const Locale& locale); +#endif /* U_HIDE_INTERNAL_API */ + + /** + * Sets the default time zone (i.e., what's returned by createDefault()) to be the + * specified time zone. If nullptr is specified for the time zone, the default time + * zone is set to the default host time zone. This call adopts the TimeZone object + * passed in; the client is no longer responsible for deleting it. + * + * @param zone A pointer to the new TimeZone object to use as the default. + * @stable ICU 2.0 + */ + static void U_EXPORT2 adoptDefault(TimeZone* zone); + +#ifndef U_HIDE_SYSTEM_API + /** + * Same as adoptDefault(), except that the TimeZone object passed in is NOT adopted; + * the caller remains responsible for deleting it. + * + * @param zone The given timezone. + * @system + * @stable ICU 2.0 + */ + static void U_EXPORT2 setDefault(const TimeZone& zone); +#endif /* U_HIDE_SYSTEM_API */ + + /** + * Returns the timezone data version currently used by ICU. + * @param status Output param to filled in with a success or an error. + * @return the version string, such as "2007f" + * @stable ICU 3.8 + */ + static const char* U_EXPORT2 getTZDataVersion(UErrorCode& status); + + /** + * Returns the canonical system timezone ID or the normalized + * custom time zone ID for the given time zone ID. + * @param id The input time zone ID to be canonicalized. + * @param canonicalID Receives the canonical system time zone ID + * or the custom time zone ID in normalized format. + * @param status Receives the status. When the given time zone ID + * is neither a known system time zone ID nor a + * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR + * is set. + * @return A reference to the result. + * @stable ICU 4.0 + */ + static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, + UnicodeString& canonicalID, UErrorCode& status); + + /** + * Returns the canonical system time zone ID or the normalized + * custom time zone ID for the given time zone ID. + * @param id The input time zone ID to be canonicalized. + * @param canonicalID Receives the canonical system time zone ID + * or the custom time zone ID in normalized format. + * @param isSystemID Receives if the given ID is a known system + * time zone ID. + * @param status Receives the status. When the given time zone ID + * is neither a known system time zone ID nor a + * valid custom time zone ID, U_ILLEGAL_ARGUMENT_ERROR + * is set. + * @return A reference to the result. + * @stable ICU 4.0 + */ + static UnicodeString& U_EXPORT2 getCanonicalID(const UnicodeString& id, + UnicodeString& canonicalID, UBool& isSystemID, UErrorCode& status); + + /** + * Converts a system time zone ID to an equivalent Windows time zone ID. For example, + * Windows time zone ID "Pacific Standard Time" is returned for input "America/Los_Angeles". + * + * <p>There are system time zones that cannot be mapped to Windows zones. When the input + * system time zone ID is unknown or unmappable to a Windows time zone, then the result will be + * empty, but the operation itself remains successful (no error status set on return). + * + * <p>This implementation utilizes <a href="http://unicode.org/cldr/charts/supplemental/zone_tzid.html"> + * Zone-Tzid mapping data</a>. The mapping data is updated time to time. To get the latest changes, + * please read the ICU user guide section <a href="https://unicode-org.github.io/icu/userguide/datetime/timezone#updating-the-time-zone-data"> + * Updating the Time Zone Data</a>. + * + * @param id A system time zone ID. + * @param winid Receives a Windows time zone ID. When the input system time zone ID is unknown + * or unmappable to a Windows time zone ID, then an empty string is set on return. + * @param status Receives the status. + * @return A reference to the result (<code>winid</code>). + * @see getIDForWindowsID + * + * @stable ICU 52 + */ + static UnicodeString& U_EXPORT2 getWindowsID(const UnicodeString& id, + UnicodeString& winid, UErrorCode& status); + + /** + * Converts a Windows time zone ID to an equivalent system time zone ID + * for a region. For example, system time zone ID "America/Los_Angeles" is returned + * for input Windows ID "Pacific Standard Time" and region "US" (or <code>null</code>), + * "America/Vancouver" is returned for the same Windows ID "Pacific Standard Time" and + * region "CA". + * + * <p>Not all Windows time zones can be mapped to system time zones. When the input + * Windows time zone ID is unknown or unmappable to a system time zone, then the result + * will be empty, but the operation itself remains successful (no error status set on return). + * + * <p>This implementation utilizes <a href="http://unicode.org/cldr/charts/supplemental/zone_tzid.html"> + * Zone-Tzid mapping data</a>. The mapping data is updated time to time. To get the latest changes, + * please read the ICU user guide section <a href="https://unicode-org.github.io/icu/userguide/datetime/timezone#updating-the-time-zone-data"> + * Updating the Time Zone Data</a>. + * + * @param winid A Windows time zone ID. + * @param region A NUL-terminated region code, or <code>nullptr</code> if no regional preference. + * @param id Receives a system time zone ID. When the input Windows time zone ID is unknown + * or unmappable to a system time zone ID, then an empty string is set on return. + * @param status Receives the status. + * @return A reference to the result (<code>id</code>). + * @see getWindowsID + * + * @stable ICU 52 + */ + static UnicodeString& U_EXPORT2 getIDForWindowsID(const UnicodeString& winid, const char* region, + UnicodeString& id, UErrorCode& status); + + /** + * Returns true if the two TimeZones are equal. (The TimeZone version only compares + * IDs, but subclasses are expected to also compare the fields they add.) + * + * @param that The TimeZone object to be compared with. + * @return true if the given TimeZone is equal to this TimeZone; false + * otherwise. + * @stable ICU 2.0 + */ + virtual bool operator==(const TimeZone& that) const; + + /** + * Returns true if the two TimeZones are NOT equal; that is, if operator==() returns + * false. + * + * @param that The TimeZone object to be compared with. + * @return true if the given TimeZone is not equal to this TimeZone; false + * otherwise. + * @stable ICU 2.0 + */ + bool operator!=(const TimeZone& that) const {return !operator==(that);} + + /** + * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add + * to GMT to get local time in this time zone, taking daylight savings time into + * account) as of a particular reference date. The reference date is used to determine + * whether daylight savings time is in effect and needs to be figured into the offset + * that is returned (in other words, what is the adjusted GMT offset in this time zone + * at this particular date and time?). For the time zones produced by createTimeZone(), + * the reference data is specified according to the Gregorian calendar, and the date + * and time fields are local standard time. + * + * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, + * which returns both the raw and the DST offset for a given time. This method + * is retained only for backward compatibility. + * + * @param era The reference date's era + * @param year The reference date's year + * @param month The reference date's month (0-based; 0 is January) + * @param day The reference date's day-in-month (1-based) + * @param dayOfWeek The reference date's day-of-week (1-based; 1 is Sunday) + * @param millis The reference date's milliseconds in day, local standard time + * @param status Output param to filled in with a success or an error. + * @return The offset in milliseconds to add to GMT to get local time. + * @stable ICU 2.0 + */ + virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, + uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const = 0; + + /** + * Gets the time zone offset, for current date, modified in case of + * daylight savings. This is the offset to add *to* UTC to get local time. + * + * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload, + * which returns both the raw and the DST offset for a given time. This method + * is retained only for backward compatibility. + * + * @param era the era of the given date. + * @param year the year in the given date. + * @param month the month in the given date. + * Month is 0-based. e.g., 0 for January. + * @param day the day-in-month of the given date. + * @param dayOfWeek the day-of-week of the given date. + * @param milliseconds the millis in day in <em>standard</em> local time. + * @param monthLength the length of the given month in days. + * @param status Output param to filled in with a success or an error. + * @return the offset to add *to* GMT to get local time. + * @stable ICU 2.0 + */ + virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day, + uint8_t dayOfWeek, int32_t milliseconds, + int32_t monthLength, UErrorCode& status) const = 0; + + /** + * Returns the time zone raw and GMT offset for the given moment + * in time. Upon return, local-millis = GMT-millis + rawOffset + + * dstOffset. All computations are performed in the proleptic + * Gregorian calendar. The default implementation in the TimeZone + * class delegates to the 8-argument getOffset(). + * + * @param date moment in time for which to return offsets, in + * units of milliseconds from January 1, 1970 0:00 GMT, either GMT + * time or local wall time, depending on `local'. + * @param local if true, `date' is local wall time; otherwise it + * is in GMT time. + * @param rawOffset output parameter to receive the raw offset, that + * is, the offset not including DST adjustments + * @param dstOffset output parameter to receive the DST offset, + * that is, the offset to be added to `rawOffset' to obtain the + * total offset between local and GMT time. If DST is not in + * effect, this value is zero; otherwise it is a positive value, + * typically one hour. + * @param ec input-output error code + * + * @stable ICU 2.8 + */ + virtual void getOffset(UDate date, UBool local, int32_t& rawOffset, + int32_t& dstOffset, UErrorCode& ec) const; + + /** + * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add + * to GMT to get local time, before taking daylight savings time into account). + * + * @param offsetMillis The new raw GMT offset for this time zone. + * @stable ICU 2.0 + */ + virtual void setRawOffset(int32_t offsetMillis) = 0; + + /** + * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add + * to GMT to get local time, before taking daylight savings time into account). + * + * @return The TimeZone's raw GMT offset. + * @stable ICU 2.0 + */ + virtual int32_t getRawOffset(void) const = 0; + + /** + * Fills in "ID" with the TimeZone's ID. + * + * @param ID Receives this TimeZone's ID. + * @return A reference to 'ID' + * @stable ICU 2.0 + */ + UnicodeString& getID(UnicodeString& ID) const; + + /** + * Sets the TimeZone's ID to the specified value. This doesn't affect any other + * fields (for example, if you say< + * blockquote><pre> + * . TimeZone* foo = TimeZone::createTimeZone("America/New_York"); + * . foo.setID("America/Los_Angeles"); + * </pre>\htmlonly</blockquote>\endhtmlonly + * the time zone's GMT offset and daylight-savings rules don't change to those for + * Los Angeles. They're still those for New York. Only the ID has changed.) + * + * @param ID The new time zone ID. + * @stable ICU 2.0 + */ + void setID(const UnicodeString& ID); + + /** + * Enum for use with getDisplayName + * @stable ICU 2.4 + */ + enum EDisplayType { + /** + * Selector for short display name + * @stable ICU 2.4 + */ + SHORT = 1, + /** + * Selector for long display name + * @stable ICU 2.4 + */ + LONG, + /** + * Selector for short generic display name + * @stable ICU 4.4 + */ + SHORT_GENERIC, + /** + * Selector for long generic display name + * @stable ICU 4.4 + */ + LONG_GENERIC, + /** + * Selector for short display name derived + * from time zone offset + * @stable ICU 4.4 + */ + SHORT_GMT, + /** + * Selector for long display name derived + * from time zone offset + * @stable ICU 4.4 + */ + LONG_GMT, + /** + * Selector for short display name derived + * from the time zone's fallback name + * @stable ICU 4.4 + */ + SHORT_COMMONLY_USED, + /** + * Selector for long display name derived + * from the time zone's fallback name + * @stable ICU 4.4 + */ + GENERIC_LOCATION + }; + + /** + * Returns a name of this time zone suitable for presentation to the user + * in the default locale. + * This method returns the long name, not including daylight savings. + * If the display name is not available for the locale, + * then this method returns a string in the localized GMT offset format + * such as <code>GMT[+-]HH:mm</code>. + * @param result the human-readable name of this time zone in the default locale. + * @return A reference to 'result'. + * @stable ICU 2.0 + */ + UnicodeString& getDisplayName(UnicodeString& result) const; + + /** + * Returns a name of this time zone suitable for presentation to the user + * in the specified locale. + * This method returns the long name, not including daylight savings. + * If the display name is not available for the locale, + * then this method returns a string in the localized GMT offset format + * such as <code>GMT[+-]HH:mm</code>. + * @param locale the locale in which to supply the display name. + * @param result the human-readable name of this time zone in the given locale + * or in the default locale if the given locale is not recognized. + * @return A reference to 'result'. + * @stable ICU 2.0 + */ + UnicodeString& getDisplayName(const Locale& locale, UnicodeString& result) const; + + /** + * Returns a name of this time zone suitable for presentation to the user + * in the default locale. + * If the display name is not available for the locale, + * then this method returns a string in the localized GMT offset format + * such as <code>GMT[+-]HH:mm</code>. + * @param inDaylight if true, return the daylight savings name. + * @param style + * @param result the human-readable name of this time zone in the default locale. + * @return A reference to 'result'. + * @stable ICU 2.0 + */ + UnicodeString& getDisplayName(UBool inDaylight, EDisplayType style, UnicodeString& result) const; + + /** + * Returns a name of this time zone suitable for presentation to the user + * in the specified locale. + * If the display name is not available for the locale, + * then this method returns a string in the localized GMT offset format + * such as <code>GMT[+-]HH:mm</code>. + * @param inDaylight if true, return the daylight savings name. + * @param style + * @param locale the locale in which to supply the display name. + * @param result the human-readable name of this time zone in the given locale + * or in the default locale if the given locale is not recognized. + * @return A reference to 'result'. + * @stable ICU 2.0 + */ + UnicodeString& getDisplayName(UBool inDaylight, EDisplayType style, const Locale& locale, UnicodeString& result) const; + + /** + * Queries if this time zone uses daylight savings time. + * @return true if this time zone uses daylight savings time, + * false, otherwise. + * <p><strong>Note:</strong>The default implementation of + * ICU TimeZone uses the tz database, which supports historic + * rule changes, for system time zones. With the implementation, + * there are time zones that used daylight savings time in the + * past, but no longer used currently. For example, Asia/Tokyo has + * never used daylight savings time since 1951. Most clients would + * expect that this method to return <code>false</code> for such case. + * The default implementation of this method returns <code>true</code> + * when the time zone uses daylight savings time in the current + * (Gregorian) calendar year. + * <p>In Java 7, <code>observesDaylightTime()</code> was added in + * addition to <code>useDaylightTime()</code>. In Java, <code>useDaylightTime()</code> + * only checks if daylight saving time is observed by the last known + * rule. This specification might not be what most users would expect + * if daylight saving time is currently observed, but not scheduled + * in future. In this case, Java's <code>userDaylightTime()</code> returns + * <code>false</code>. To resolve the issue, Java 7 added <code>observesDaylightTime()</code>, + * which takes the current rule into account. The method <code>observesDaylightTime()</code> + * was added in ICU4J for supporting API signature compatibility with JDK. + * In general, ICU4C also provides JDK compatible methods, but the current + * implementation <code>userDaylightTime()</code> serves the purpose + * (takes the current rule into account), <code>observesDaylightTime()</code> + * is not added in ICU4C. In addition to <code>useDaylightTime()</code>, ICU4C + * <code>BasicTimeZone</code> class (Note that <code>TimeZone::createTimeZone(const UnicodeString &ID)</code> + * always returns a <code>BasicTimeZone</code>) provides a series of methods allowing + * historic and future time zone rule iteration, so you can check if daylight saving + * time is observed or not within a given period. + * + * @stable ICU 2.0 + */ + virtual UBool useDaylightTime(void) const = 0; + +#ifndef U_FORCE_HIDE_DEPRECATED_API + /** + * Queries if the given date is in daylight savings time in + * this time zone. + * This method is wasteful since it creates a new GregorianCalendar and + * deletes it each time it is called. This is a deprecated method + * and provided only for Java compatibility. + * + * @param date the given UDate. + * @param status Output param filled in with success/error code. + * @return true if the given date is in daylight savings time, + * false, otherwise. + * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead. + */ + virtual UBool inDaylightTime(UDate date, UErrorCode& status) const = 0; +#endif // U_FORCE_HIDE_DEPRECATED_API + + /** + * Returns true if this zone has the same rule and offset as another zone. + * That is, if this zone differs only in ID, if at all. + * @param other the <code>TimeZone</code> object to be compared with + * @return true if the given zone is the same as this one, + * with the possible exception of the ID + * @stable ICU 2.0 + */ + virtual UBool hasSameRules(const TimeZone& other) const; + + /** + * Clones TimeZone objects polymorphically. Clients are responsible for deleting + * the TimeZone object cloned. + * + * @return A new copy of this TimeZone object. + * @stable ICU 2.0 + */ + virtual TimeZone* clone() const = 0; + + /** + * Return the class ID for this class. This is useful only for + * comparing to a return value from getDynamicClassID(). + * @return The class ID for all objects of this class. + * @stable ICU 2.0 + */ + static UClassID U_EXPORT2 getStaticClassID(void); + + /** + * Returns a unique class ID POLYMORPHICALLY. This method is to + * implement a simple version of RTTI, since not all C++ compilers support genuine + * RTTI. Polymorphic operator==() and clone() methods call this method. + * <P> + * Concrete subclasses of TimeZone must use the UOBJECT_DEFINE_RTTI_IMPLEMENTATION + * macro from uobject.h in their implementation to provide correct RTTI information. + * @return The class ID for this object. All objects of a given class have the + * same class ID. Objects of other classes have different class IDs. + * @stable ICU 2.0 + */ + virtual UClassID getDynamicClassID(void) const override = 0; + + /** + * Returns the amount of time to be added to local standard time + * to get local wall clock time. + * <p> + * The default implementation always returns 3600000 milliseconds + * (i.e., one hour) if this time zone observes Daylight Saving + * Time. Otherwise, 0 (zero) is returned. + * <p> + * If an underlying TimeZone implementation subclass supports + * historical Daylight Saving Time changes, this method returns + * the known latest daylight saving value. + * + * @return the amount of saving time in milliseconds + * @stable ICU 3.6 + */ + virtual int32_t getDSTSavings() const; + + /** + * Gets the region code associated with the given + * system time zone ID. The region code is either ISO 3166 + * 2-letter country code or UN M.49 3-digit area code. + * When the time zone is not associated with a specific location, + * for example - "Etc/UTC", "EST5EDT", then this method returns + * "001" (UN M.49 area code for World). + * + * @param id The system time zone ID. + * @param region Output buffer for receiving the region code. + * @param capacity The size of the output buffer. + * @param status Receives the status. When the given time zone ID + * is not a known system time zone ID, + * U_ILLEGAL_ARGUMENT_ERROR is set. + * @return The length of the output region code. + * @stable ICU 4.8 + */ + static int32_t U_EXPORT2 getRegion(const UnicodeString& id, + char *region, int32_t capacity, UErrorCode& status); + +protected: + + /** + * Default constructor. ID is initialized to the empty string. + * @stable ICU 2.0 + */ + TimeZone(); + + /** + * Construct a TimeZone with a given ID. + * @param id a system time zone ID + * @stable ICU 2.0 + */ + TimeZone(const UnicodeString &id); + + /** + * Copy constructor. + * @param source the object to be copied. + * @stable ICU 2.0 + */ + TimeZone(const TimeZone& source); + + /** + * Default assignment operator. + * @param right the object to be copied. + * @stable ICU 2.0 + */ + TimeZone& operator=(const TimeZone& right); + +#ifndef U_HIDE_INTERNAL_API + /** + * Utility function. For internally loading rule data. + * @param top Top resource bundle for tz data + * @param ruleid ID of rule to load + * @param oldbundle Old bundle to reuse or nullptr + * @param status Status parameter + * @return either a new bundle or *oldbundle + * @internal + */ + static UResourceBundle* loadRule(const UResourceBundle* top, const UnicodeString& ruleid, UResourceBundle* oldbundle, UErrorCode&status); +#endif /* U_HIDE_INTERNAL_API */ + +private: + friend class ZoneMeta; + + + static TimeZone* createCustomTimeZone(const UnicodeString&); // Creates a time zone based on the string. + + /** + * Finds the given ID in the Olson tzdata. If the given ID is found in the tzdata, + * returns the pointer to the ID resource. This method is exposed through ZoneMeta class + * for ICU internal implementation and useful for building hashtable using a time zone + * ID as a key. + * @param id zone id string + * @return the pointer of the ID resource, or nullptr. + */ + static const char16_t* findID(const UnicodeString& id); + + /** + * Resolve a link in Olson tzdata. When the given id is known and it's not a link, + * the id itself is returned. When the given id is known and it is a link, then + * dereferenced zone id is returned. When the given id is unknown, then it returns + * nullptr. + * @param id zone id string + * @return the dereferenced zone or nullptr + */ + static const char16_t* dereferOlsonLink(const UnicodeString& id); + + /** + * Returns the region code associated with the given zone, + * or nullptr if the zone is not known. + * @param id zone id string + * @return the region associated with the given zone + */ + static const char16_t* getRegion(const UnicodeString& id); + + public: +#ifndef U_HIDE_INTERNAL_API + /** + * Returns the region code associated with the given zone, + * or nullptr if the zone is not known. + * @param id zone id string + * @param status Status parameter + * @return the region associated with the given zone + * @internal + */ + static const char16_t* getRegion(const UnicodeString& id, UErrorCode& status); +#endif /* U_HIDE_INTERNAL_API */ + + private: + /** + * Parses the given custom time zone identifier + * @param id id A string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or + * GMT[+-]hh. + * @param sign Receives parsed sign, 1 for positive, -1 for negative. + * @param hour Receives parsed hour field + * @param minute Receives parsed minute field + * @param second Receives parsed second field + * @return Returns true when the given custom id is valid. + */ + static UBool parseCustomID(const UnicodeString& id, int32_t& sign, int32_t& hour, + int32_t& minute, int32_t& second); + + /** + * Parse a custom time zone identifier and return the normalized + * custom time zone identifier for the given custom id string. + * @param id a string of the form GMT[+-]hh:mm, GMT[+-]hhmm, or + * GMT[+-]hh. + * @param normalized Receives the normalized custom ID + * @param status Receives the status. When the input ID string is invalid, + * U_ILLEGAL_ARGUMENT_ERROR is set. + * @return The normalized custom id string. + */ + static UnicodeString& getCustomID(const UnicodeString& id, UnicodeString& normalized, + UErrorCode& status); + + /** + * Returns the normalized custom time zone ID for the given offset fields. + * @param hour offset hours + * @param min offset minutes + * @param sec offset seconds + * @param negative sign of the offset, true for negative offset. + * @param id Receives the format result (normalized custom ID) + * @return The reference to id + */ + static UnicodeString& formatCustomID(int32_t hour, int32_t min, int32_t sec, + UBool negative, UnicodeString& id); + + UnicodeString fID; // this time zone's ID + + friend class TZEnumeration; +}; + + +// ------------------------------------- + +inline UnicodeString& +TimeZone::getID(UnicodeString& ID) const +{ + ID = fID; + return ID; +} + +// ------------------------------------- + +inline void +TimeZone::setID(const UnicodeString& ID) +{ + fID = ID; +} +U_NAMESPACE_END + +#endif /* #if !UCONFIG_NO_FORMATTING */ + +#endif /* U_SHOW_CPLUSPLUS_API */ + +#endif //_TIMEZONE +//eof |