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// © 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-NULL.
* 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 NULL, no filtering
* done by region.
* @param rawOffset An offset from GMT in milliseconds, ignoring
* the effect of daylight savings time, if any.
* When NULL, 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);
/**
* 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);
/**
* 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);
/**
* Sets the default time zone (i.e., what's returned by createDefault()) 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 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="http://userguide.icu-project.org/datetime/timezone#TOC-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="http://userguide.icu-project.org/datetime/timezone#TOC-Updating-the-Time-Zone-Data">
* Updating the Time Zone Data</a>.
*
* @param winid A Windows time zone ID.
* @param region A null-terminated region code, or <code>NULL</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 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
*
* @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 = 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 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);
#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 NULL.
*/
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
* NULL.
* @param id zone id string
* @return the dereferenced zone or NULL
*/
static const char16_t* dereferOlsonLink(const UnicodeString& id);
/**
* Returns the region code associated with the given zone,
* or NULL 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 NULL 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 Receves 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 Receves 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
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