/* * Copyright (C) {1997-2004}, 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 !UCONFIG_NO_FORMATTING #include "unicode/uobject.h" #include "unicode/unistr.h" #include "unicode/ures.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 Pacific * Standard Time zone is "PST". So, you can get a PST <code>TimeZone</code> object * with: * \htmlonly<blockquote>\endhtmlonly * <pre> * TimeZone *tz = TimeZone::createTimeZone("PST"); * </pre> * \htmlonly</blockquote>\endhtmlonly * You can use <code>getAvailableIDs</code> method to iterate through * all the supported time zone IDs. 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 does not include * daylight savings time. * * 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 only have one * TimeZone subclass: SimpleTimeZone.) * <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, Pacific * Standard 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/LosAngeles"). * 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(); /** * The GMT time zone has a raw offset of zero and does not use daylight * savings time. This is a commonly used time zone. * @return the GMT time zone. * @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>, either an abbreviation such as * "PST", a full name such as "America/Los_Angeles", or a custom ID * such as "GMT-8:00". * @return the specified <code>TimeZone</code>, or the GMT zone if the given ID * cannot be understood. Return result guaranteed to be non-null. If you * require that the specific zone asked for be returned, check the ID of the * return result. * @stable ICU 2.0 */ static TimeZone* U_EXPORT2 createTimeZone(const UnicodeString& ID); /** * Returns an enumeration over all recognized time zone IDs. (i.e., * all strings that createTimeZone() accepts) * * @return an enumeration object, owned by the caller. * @stable ICU 2.4 */ static StringEnumeration* U_EXPORT2 createEnumeration(); /** * 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 * @stable ICU 2.4 */ static StringEnumeration* U_EXPORT2 createEnumeration(int32_t rawOffset); /** * Returns an enumeration over time zone IDs associated with the * given country. Some zones are affiliated with no country * (e.g., "UTC"); these may also be retrieved, as a group. * * @param country The ISO 3166 two-letter country code, or NULL to * retrieve zones not affiliated with any country. * @return an enumeration object, owned by the caller * @stable ICU 2.4 */ static StringEnumeration* U_EXPORT2 createEnumeration(const char* country); #ifdef U_USE_TIMEZONE_OBSOLETE_2_8 /** * Returns a list of time zone IDs, one for each time zone with a given GMT offset. * The return value is a list because 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. So if you ask for * the time zone IDs corresponding to GMT-7:00, you'll get back 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. * <P> * The caller owns the list that is returned, but does not own the strings contained * in that list. Delete the array with uprv_free(), but DON'T delete the elements in the array. * * <p>NOTE: uprv_free() is declared in the private header source/common/cmemory.h. * * @param rawOffset An offset from GMT in milliseconds. * @param numIDs Receives the number of items in the array that is returned. * @return An array of UnicodeString pointers, where each UnicodeString is * a time zone ID for a time zone with the given GMT offset. If * there is no timezone that matches the GMT offset * specified, NULL is returned. * @obsolete ICU 2.8. Use createEnumeration(int32_t) instead since this API will be removed in that release. */ static const UnicodeString** createAvailableIDs(int32_t rawOffset, int32_t& numIDs); /** * Returns a list of time zone IDs associated with the given * country. Some zones are affiliated with no country (e.g., * "UTC"); these may also be retrieved, as a group. * * <P>The caller owns the list that is returned, but does not own * the strings contained in that list. Delete the array with uprv_free(), but * <b>DON'T</b> delete the elements in the array. * * <p>NOTE: uprv_free() is declared in the private header source/common/cmemory.h. * * @param country The ISO 3166 two-letter country code, or NULL to * retrieve zones not affiliated with any country. * @param numIDs Receives the number of items in the array that is * returned. * @return An array of UnicodeString pointers, where each * UnicodeString is a time zone ID for a time zone with the given * country. If there is no timezone that matches the country * specified, NULL is returned. * @obsolete ICU 2.8. Use createEnumeration(const char*) instead since this API will be removed in that release. */ static const UnicodeString** createAvailableIDs(const char* country, int32_t& numIDs); /** * Returns a list of all time zone IDs supported by the TimeZone class (i.e., all * IDs that it's legal to pass to createTimeZone()). The caller owns the list that * is returned, but does not own the strings contained in that list. Delete the array with uprv_free(), * but DON'T delete the elements in the array. * * <p>NOTE: uprv_free() is declared in the private header source/common/cmemory.h. * * @param numIDs Receives the number of zone IDs returned. * @return An array of UnicodeString pointers, where each is a time zone ID * supported by the TimeZone class. * @obsolete ICU 2.8. Use createEnumeration(void) instead since this API will be removed in that release. */ static const UnicodeString** createAvailableIDs(int32_t& numIDs); #endif /** * 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 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 system using methods in TPlatformUtilities. If the * system routines fail, or if they specify a TimeZone or TimeZone offset which is not * recognized, the TimeZone indicated by the ID kLastResortID is instantiated * and made the default. * * @return A default TimeZone. Clients are responsible for deleting the time zone * object returned. * @stable ICU 2.0 */ static TimeZone* U_EXPORT2 createDefault(void); /** * Sets the default time zone (i.e., what's returned by getDefault()) to be the * specified time zone. If NULL 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 clent 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); /** * 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 */ static void U_EXPORT2 setDefault(const TimeZone& zone); /** * 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 UBool 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 */ UBool 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 * * @draft 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 timezone 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 }; /** * 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 format * <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 format * <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 format * <code>GMT[+-]hh:mm</code>. * @param daylight if true, return the daylight savings name. * @param style either <code>LONG</code> or <code>SHORT</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(UBool daylight, 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 format * <code>GMT[+-]hh:mm</code>. * @param daylight if true, return the daylight savings name. * @param style either <code>LONG</code> or <code>SHORT</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 refence to 'result'. * @stable ICU 2.0 */ UnicodeString& getDisplayName(UBool daylight, 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. * @stable ICU 2.0 */ virtual UBool useDaylightTime(void) const = 0; /** * 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; /** * 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(void) 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 = 0; 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); /** * 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 NULL * @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); private: static TimeZone* createCustomTimeZone(const UnicodeString&); // Creates a time zone based on the string. /** * Responsible for setting up DEFAULT_ZONE. Uses routines in TPlatformUtilities * (i.e., platform-specific calls) to get the current system time zone. Failing * that, uses the platform-specific default time zone. Failing that, uses GMT. */ static void initDefault(void); // See source file for documentation /** * Lookup the given name in our system zone table. If found, * instantiate a new zone of that name and return it. If not * found, return 0. * @param name tthe given name of a system time zone. * @return the timezone indicated by the 'name'. */ static TimeZone* createSystemTimeZone(const UnicodeString& name); UnicodeString fID; // this time zone's ID }; // ------------------------------------- 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 //_TIMEZONE //eof