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// © 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 = 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 transtion 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;
#ifndef U_HIDE_INTERNAL_API
/**
* The time type option bit flags used by getOffsetFromLocal
* @internal
*/
enum {
kStandard = 0x01,
kDaylight = 0x03,
kFormer = 0x04,
kLatter = 0x0C
};
#endif /* U_HIDE_INTERNAL_API */
/**
* Get time zone offsets from local wall time.
* @internal
*/
virtual void getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt,
int32_t& rawOffset, int32_t& dstOffset, UErrorCode& status) const;
protected:
#ifndef U_HIDE_INTERNAL_API
/**
* The time type option bit masks used by getOffsetFromLocal
* @internal
*/
enum {
kStdDstMask = kDaylight,
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);
/**
* 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 Receives the InitialTimeZone, always not NULL
* @param transitionRules Receives the transition rules, could be NULL
* @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