Edit File: basictz.h
// © 2016 and later: Unicode, Inc. and others. // License & terms of use: http://www.unicode.org/copyright.html /* ******************************************************************************* * Copyright (C) 2007-2013, International Business Machines Corporation and * others. All Rights Reserved. ******************************************************************************* */ #ifndef BASICTZ_H #define BASICTZ_H /** * \file * \brief C++ API: ICU TimeZone base class */ #include "unicode/utypes.h" #if U_SHOW_CPLUSPLUS_API #if !UCONFIG_NO_FORMATTING #include "unicode/timezone.h" #include "unicode/tzrule.h" #include "unicode/tztrans.h" U_NAMESPACE_BEGIN // forward declarations class UVector; /** * <code>BasicTimeZone</code> is an abstract class extending <code>TimeZone</code>. * This class provides some additional methods to access time zone transitions and rules. * All ICU <code>TimeZone</code> concrete subclasses extend this class. * @stable ICU 3.8 */ class U_I18N_API BasicTimeZone: public TimeZone { public: /** * Destructor. * @stable ICU 3.8 */ virtual ~BasicTimeZone(); /** * Clones this object polymorphically. * The caller owns the result and should delete it when done. * @return clone, or nullptr if an error occurred * @stable ICU 3.8 */ virtual BasicTimeZone* clone() const override = 0; /** * Gets the first time zone transition after the base time. * @param base The base time. * @param inclusive Whether the base time is inclusive or not. * @param result Receives the first transition after the base time. * @return true if the transition is found. * @stable ICU 3.8 */ virtual UBool getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const = 0; /** * Gets the most recent time zone transition before the base time. * @param base The base time. * @param inclusive Whether the base time is inclusive or not. * @param result Receives the most recent transition before the base time. * @return true if the transition is found. * @stable ICU 3.8 */ virtual UBool getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const = 0; /** * Checks if the time zone has equivalent transitions in the time range. * This method returns true when all of transition times, from/to standard * offsets and DST savings used by this time zone match the other in the * time range. * @param tz The <code>BasicTimeZone</code> object to be compared with. * @param start The start time of the evaluated time range (inclusive) * @param end The end time of the evaluated time range (inclusive) * @param ignoreDstAmount * When true, any transitions with only daylight saving amount * changes will be ignored, except either of them is zero. * For example, a transition from rawoffset 3:00/dstsavings 1:00 * to rawoffset 2:00/dstsavings 2:00 is excluded from the comparison, * but a transition from rawoffset 2:00/dstsavings 1:00 to * rawoffset 3:00/dstsavings 0:00 is included. * @param ec Output param to filled in with a success or an error. * @return true if the other time zone has the equivalent transitions in the * time range. * @stable ICU 3.8 */ virtual UBool hasEquivalentTransitions(const BasicTimeZone& tz, UDate start, UDate end, UBool ignoreDstAmount, UErrorCode& ec) const; /** * Returns the number of <code>TimeZoneRule</code>s which represents time transitions, * for this time zone, that is, all <code>TimeZoneRule</code>s for this time zone except * <code>InitialTimeZoneRule</code>. The return value range is 0 or any positive value. * @param status Receives error status code. * @return The number of <code>TimeZoneRule</code>s representing time transitions. * @stable ICU 3.8 */ virtual int32_t countTransitionRules(UErrorCode& status) const = 0; /** * Gets the <code>InitialTimeZoneRule</code> and the set of <code>TimeZoneRule</code> * which represent time transitions for this time zone. On successful return, * the argument initial points to non-NULL <code>InitialTimeZoneRule</code> and * the array trsrules is filled with 0 or multiple <code>TimeZoneRule</code> * instances up to the size specified by trscount. The results are referencing the * rule instance held by this time zone instance. Therefore, after this time zone * is destructed, they are no longer available. * @param initial Receives the initial timezone rule * @param trsrules Receives the timezone transition rules * @param trscount On input, specify the size of the array 'transitions' receiving * the timezone transition rules. On output, actual number of * rules filled in the array will be set. * @param status Receives error status code. * @stable ICU 3.8 */ virtual void getTimeZoneRules(const InitialTimeZoneRule*& initial, const TimeZoneRule* trsrules[], int32_t& trscount, UErrorCode& status) const = 0; /** * Gets the set of time zone rules valid at the specified time. Some known external time zone * implementations are not capable to handle historic time zone rule changes. Also some * implementations can only handle certain type of rule definitions. * If this time zone does not use any daylight saving time within about 1 year from the specified * time, only the <code>InitialTimeZone</code> is returned. Otherwise, the rule for standard * time and daylight saving time transitions are returned in addition to the * <code>InitialTimeZoneRule</code>. The standard and daylight saving time transition rules are * represented by <code>AnnualTimeZoneRule</code> with <code>DateTimeRule::DOW</code> for its date * rule and <code>DateTimeRule::WALL_TIME</code> for its time rule. Because daylight saving time * rule is changing time to time in many time zones and also mapping a transition time rule to * different type is lossy transformation, the set of rules returned by this method may be valid * for short period of time. * The time zone rule objects returned by this method is owned by the caller, so the caller is * responsible for deleting them after use. * @param date The date used for extracting time zone rules. * @param initial Receives the <code>InitialTimeZone</code>, always not NULL. * @param std Receives the <code>AnnualTimeZoneRule</code> for standard time transitions. * When this time time zone does not observe daylight saving times around the * specified date, NULL is set. * @param dst Receives the <code>AnnualTimeZoneRule</code> for daylight saving time * transitions. When this time zone does not observer daylight saving times * around the specified date, NULL is set. * @param status Receives error status code. * @stable ICU 3.8 */ virtual void getSimpleRulesNear(UDate date, InitialTimeZoneRule*& initial, AnnualTimeZoneRule*& std, AnnualTimeZoneRule*& dst, UErrorCode& status) const; /** * Get time zone offsets from local wall time. * @stable ICU 69 */ virtual void getOffsetFromLocal( UDate date, UTimeZoneLocalOption nonExistingTimeOpt, UTimeZoneLocalOption duplicatedTimeOpt, int32_t& rawOffset, int32_t& dstOffset, UErrorCode& status) const; #ifndef U_HIDE_INTERNAL_API /** * The time type option bit flags used by getOffsetFromLocal * @internal */ enum { kStandard = 0x01, kDaylight = 0x03, kFormer = 0x04, /* UCAL_TZ_LOCAL_FORMER */ kLatter = 0x0C /* UCAL_TZ_LOCAL_LATTER */ }; /** * Get time zone offsets from local wall time. * @internal */ void getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt, int32_t& rawOffset, int32_t& dstOffset, UErrorCode& status) const; #endif /* U_HIDE_INTERNAL_API */ protected: #ifndef U_HIDE_INTERNAL_API /** * A time type option bit mask used by getOffsetFromLocal. * @internal */ static constexpr int32_t kStdDstMask = kDaylight; /** * A time type option bit mask used by getOffsetFromLocal. * @internal */ static constexpr int32_t kFormerLatterMask = kLatter; #endif /* U_HIDE_INTERNAL_API */ /** * Default constructor. * @stable ICU 3.8 */ BasicTimeZone(); /** * Construct a timezone with a given ID. * @param id a system time zone ID * @stable ICU 3.8 */ BasicTimeZone(const UnicodeString &id); /** * Copy constructor. * @param source the object to be copied. * @stable ICU 3.8 */ BasicTimeZone(const BasicTimeZone& source); /** * Copy assignment. * @stable ICU 3.8 */ BasicTimeZone& operator=(const BasicTimeZone&) = default; /** * Gets the set of TimeZoneRule instances applicable to the specified time and after. * @param start The start date used for extracting time zone rules * @param initial Output parameter, receives the InitialTimeZone. * Always not nullptr (except in case of error) * @param transitionRules Output parameter, a UVector of transition rules. * May be nullptr, if there are no transition rules. * The caller owns the returned vector; the UVector owns the rules. * @param status Receives error status code */ void getTimeZoneRulesAfter(UDate start, InitialTimeZoneRule*& initial, UVector*& transitionRules, UErrorCode& status) const; }; U_NAMESPACE_END #endif /* #if !UCONFIG_NO_FORMATTING */ #endif /* U_SHOW_CPLUSPLUS_API */ #endif // BASICTZ_H //eof
Back to File Manager