1 /*
2 *******************************************************************************
3 * Copyright (C) 2007-2013, International Business Machines Corporation and    *
4 * others. All Rights Reserved.                                                *
5 *******************************************************************************
6 */
7 #ifndef RBTZ_H
8 #define RBTZ_H
9 
10 #include "unicode/utypes.h"
11 
12 /**
13  * \file
14  * \brief C++ API: Rule based customizable time zone
15  */
16 
17 #if !UCONFIG_NO_FORMATTING
18 
19 #include "unicode/basictz.h"
20 #include "unicode/unistr.h"
21 
22 U_NAMESPACE_BEGIN
23 
24 // forward declaration
25 class UVector;
26 struct Transition;
27 
28 /**
29  * a BasicTimeZone subclass implemented in terms of InitialTimeZoneRule and TimeZoneRule instances
30  * @see BasicTimeZone
31  * @see InitialTimeZoneRule
32  * @see TimeZoneRule
33  */
34 class U_I18N_API RuleBasedTimeZone : public BasicTimeZone {
35 public:
36     /**
37      * Constructs a <code>RuleBasedTimeZone</code> object with the ID and the
38      * <code>InitialTimeZoneRule</code>.  The input <code>InitialTimeZoneRule</code>
39      * is adopted by this <code>RuleBasedTimeZone</code>, thus the caller must not
40      * delete it.
41      * @param id                The time zone ID.
42      * @param initialRule       The initial time zone rule.
43      * @stable ICU 3.8
44      */
45     RuleBasedTimeZone(const UnicodeString& id, InitialTimeZoneRule* initialRule);
46 
47     /**
48      * Copy constructor.
49      * @param source    The RuleBasedTimeZone object to be copied.
50      * @stable ICU 3.8
51      */
52     RuleBasedTimeZone(const RuleBasedTimeZone& source);
53 
54     /**
55      * Destructor.
56      * @stable ICU 3.8
57      */
58     virtual ~RuleBasedTimeZone();
59 
60     /**
61      * Assignment operator.
62      * @param right The object to be copied.
63      * @stable ICU 3.8
64      */
65     RuleBasedTimeZone& operator=(const RuleBasedTimeZone& right);
66 
67     /**
68      * Return true if the given <code>TimeZone</code> objects are
69      * semantically equal. Objects of different subclasses are considered unequal.
70      * @param that  The object to be compared with.
71      * @return  true if the given <code>TimeZone</code> objects are
72       *semantically equal.
73      * @stable ICU 3.8
74      */
75     virtual UBool operator==(const TimeZone& that) const;
76 
77     /**
78      * Return true if the given <code>TimeZone</code> objects are
79      * semantically unequal. Objects of different subclasses are considered unequal.
80      * @param that  The object to be compared with.
81      * @return  true if the given <code>TimeZone</code> objects are
82      * semantically unequal.
83      * @stable ICU 3.8
84      */
85     virtual UBool operator!=(const TimeZone& that) const;
86 
87     /**
88      * Adds the <code>TimeZoneRule</code> which represents time transitions.
89      * The <code>TimeZoneRule</code> must have start times, that is, the result
90      * of isTransitionRule() must be true. Otherwise, U_ILLEGAL_ARGUMENT_ERROR
91      * is set to the error code.
92      * The input <code>TimeZoneRule</code> is adopted by this
93      * <code>RuleBasedTimeZone</code> on successful completion of this method,
94      * thus, the caller must not delete it when no error is returned.
95      * After all rules are added, the caller must call complete() method to
96      * make this <code>RuleBasedTimeZone</code> ready to handle common time
97      * zone functions.
98      * @param rule The <code>TimeZoneRule</code>.
99      * @param status Output param to filled in with a success or an error.
100      * @stable ICU 3.8
101      */
102     void addTransitionRule(TimeZoneRule* rule, UErrorCode& status);
103 
104     /**
105      * Makes the <code>TimeZoneRule</code> ready to handle actual timezone
106      * calcuation APIs.  This method collects time zone rules specified
107      * by the caller via the constructor and addTransitionRule() and
108      * builds internal structure for making the object ready to support
109      * time zone APIs such as getOffset(), getNextTransition() and others.
110      * @param status Output param to filled in with a success or an error.
111      * @stable ICU 3.8
112      */
113     void complete(UErrorCode& status);
114 
115     /**
116      * Clones TimeZone objects polymorphically. Clients are responsible for deleting
117      * the TimeZone object cloned.
118      *
119      * @return   A new copy of this TimeZone object.
120      * @stable ICU 3.8
121      */
122     virtual TimeZone* clone(void) const;
123 
124     /**
125      * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add
126      * to GMT to get local time in this time zone, taking daylight savings time into
127      * account) as of a particular reference date.  The reference date is used to determine
128      * whether daylight savings time is in effect and needs to be figured into the offset
129      * that is returned (in other words, what is the adjusted GMT offset in this time zone
130      * at this particular date and time?).  For the time zones produced by createTimeZone(),
131      * the reference data is specified according to the Gregorian calendar, and the date
132      * and time fields are local standard time.
133      *
134      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
135      * which returns both the raw and the DST offset for a given time. This method
136      * is retained only for backward compatibility.
137      *
138      * @param era        The reference date's era
139      * @param year       The reference date's year
140      * @param month      The reference date's month (0-based; 0 is January)
141      * @param day        The reference date's day-in-month (1-based)
142      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
143      * @param millis     The reference date's milliseconds in day, local standard time
144      * @param status     Output param to filled in with a success or an error.
145      * @return           The offset in milliseconds to add to GMT to get local time.
146      * @stable ICU 3.8
147      */
148     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
149                               uint8_t dayOfWeek, int32_t millis, UErrorCode& status) const;
150 
151     /**
152      * Gets the time zone offset, for current date, modified in case of
153      * daylight savings. This is the offset to add *to* UTC to get local time.
154      *
155      * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
156      * which returns both the raw and the DST offset for a given time. This method
157      * is retained only for backward compatibility.
158      *
159      * @param era        The reference date's era
160      * @param year       The reference date's year
161      * @param month      The reference date's month (0-based; 0 is January)
162      * @param day        The reference date's day-in-month (1-based)
163      * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
164      * @param millis     The reference date's milliseconds in day, local standard time
165      * @param monthLength The length of the given month in days.
166      * @param status     Output param to filled in with a success or an error.
167      * @return           The offset in milliseconds to add to GMT to get local time.
168      * @stable ICU 3.8
169      */
170     virtual int32_t getOffset(uint8_t era, int32_t year, int32_t month, int32_t day,
171                            uint8_t dayOfWeek, int32_t millis,
172                            int32_t monthLength, UErrorCode& status) const;
173 
174     /**
175      * Returns the time zone raw and GMT offset for the given moment
176      * in time.  Upon return, local-millis = GMT-millis + rawOffset +
177      * dstOffset.  All computations are performed in the proleptic
178      * Gregorian calendar.  The default implementation in the TimeZone
179      * class delegates to the 8-argument getOffset().
180      *
181      * @param date moment in time for which to return offsets, in
182      * units of milliseconds from January 1, 1970 0:00 GMT, either GMT
183      * time or local wall time, depending on `local'.
184      * @param local if true, `date' is local wall time; otherwise it
185      * is in GMT time.
186      * @param rawOffset output parameter to receive the raw offset, that
187      * is, the offset not including DST adjustments
188      * @param dstOffset output parameter to receive the DST offset,
189      * that is, the offset to be added to `rawOffset' to obtain the
190      * total offset between local and GMT time. If DST is not in
191      * effect, this value is zero; otherwise it is a positive value,
192      * typically one hour.
193      * @param ec input-output error code
194      * @stable ICU 3.8
195      */
196     virtual void getOffset(UDate date, UBool local, int32_t& rawOffset,
197                            int32_t& dstOffset, UErrorCode& ec) const;
198 
199     /**
200      * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
201      * to GMT to get local time, before taking daylight savings time into account).
202      *
203      * @param offsetMillis  The new raw GMT offset for this time zone.
204      * @stable ICU 3.8
205      */
206     virtual void setRawOffset(int32_t offsetMillis);
207 
208     /**
209      * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
210      * to GMT to get local time, before taking daylight savings time into account).
211      *
212      * @return   The TimeZone's raw GMT offset.
213      * @stable ICU 3.8
214      */
215     virtual int32_t getRawOffset(void) const;
216 
217     /**
218      * Queries if this time zone uses daylight savings time.
219      * @return true if this time zone uses daylight savings time,
220      * false, otherwise.
221      * @stable ICU 3.8
222      */
223     virtual UBool useDaylightTime(void) const;
224 
225     /**
226      * Queries if the given date is in daylight savings time in
227      * this time zone.
228      * This method is wasteful since it creates a new GregorianCalendar and
229      * deletes it each time it is called. This is a deprecated method
230      * and provided only for Java compatibility.
231      *
232      * @param date the given UDate.
233      * @param status Output param filled in with success/error code.
234      * @return true if the given date is in daylight savings time,
235      * false, otherwise.
236      * @deprecated ICU 2.4. Use Calendar::inDaylightTime() instead.
237      */
238     virtual UBool inDaylightTime(UDate date, UErrorCode& status) const;
239 
240     /**
241      * Returns true if this zone has the same rule and offset as another zone.
242      * That is, if this zone differs only in ID, if at all.
243      * @param other the <code>TimeZone</code> object to be compared with
244      * @return true if the given zone is the same as this one,
245      * with the possible exception of the ID
246      * @stable ICU 3.8
247      */
248     virtual UBool hasSameRules(const TimeZone& other) const;
249 
250     /**
251      * Gets the first time zone transition after the base time.
252      * @param base      The base time.
253      * @param inclusive Whether the base time is inclusive or not.
254      * @param result    Receives the first transition after the base time.
255      * @return  TRUE if the transition is found.
256      * @stable ICU 3.8
257      */
258     virtual UBool getNextTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const;
259 
260     /**
261      * Gets the most recent time zone transition before the base time.
262      * @param base      The base time.
263      * @param inclusive Whether the base time is inclusive or not.
264      * @param result    Receives the most recent transition before the base time.
265      * @return  TRUE if the transition is found.
266      * @stable ICU 3.8
267      */
268     virtual UBool getPreviousTransition(UDate base, UBool inclusive, TimeZoneTransition& result) const;
269 
270     /**
271      * Returns the number of <code>TimeZoneRule</code>s which represents time transitions,
272      * for this time zone, that is, all <code>TimeZoneRule</code>s for this time zone except
273      * <code>InitialTimeZoneRule</code>.  The return value range is 0 or any positive value.
274      * @param status    Receives error status code.
275      * @return The number of <code>TimeZoneRule</code>s representing time transitions.
276      * @stable ICU 3.8
277      */
278     virtual int32_t countTransitionRules(UErrorCode& status) const;
279 
280     /**
281      * Gets the <code>InitialTimeZoneRule</code> and the set of <code>TimeZoneRule</code>
282      * which represent time transitions for this time zone.  On successful return,
283      * the argument initial points to non-NULL <code>InitialTimeZoneRule</code> and
284      * the array trsrules is filled with 0 or multiple <code>TimeZoneRule</code>
285      * instances up to the size specified by trscount.  The results are referencing the
286      * rule instance held by this time zone instance.  Therefore, after this time zone
287      * is destructed, they are no longer available.
288      * @param initial       Receives the initial timezone rule
289      * @param trsrules      Receives the timezone transition rules
290      * @param trscount      On input, specify the size of the array 'transitions' receiving
291      *                      the timezone transition rules.  On output, actual number of
292      *                      rules filled in the array will be set.
293      * @param status        Receives error status code.
294      * @stable ICU 3.8
295      */
296     virtual void getTimeZoneRules(const InitialTimeZoneRule*& initial,
297         const TimeZoneRule* trsrules[], int32_t& trscount, UErrorCode& status) const;
298 
299     /**
300      * Get time zone offsets from local wall time.
301      * @internal
302      */
303     virtual void getOffsetFromLocal(UDate date, int32_t nonExistingTimeOpt, int32_t duplicatedTimeOpt,
304         int32_t& rawOffset, int32_t& dstOffset, UErrorCode& status) const;
305 
306 private:
307     void deleteRules(void);
308     void deleteTransitions(void);
309     UVector* copyRules(UVector* source);
310     TimeZoneRule* findRuleInFinal(UDate date, UBool local,
311         int32_t NonExistingTimeOpt, int32_t DuplicatedTimeOpt) const;
312     UBool findNext(UDate base, UBool inclusive, UDate& time, TimeZoneRule*& from, TimeZoneRule*& to) const;
313     UBool findPrev(UDate base, UBool inclusive, UDate& time, TimeZoneRule*& from, TimeZoneRule*& to) const;
314     int32_t getLocalDelta(int32_t rawBefore, int32_t dstBefore, int32_t rawAfter, int32_t dstAfter,
315         int32_t NonExistingTimeOpt, int32_t DuplicatedTimeOpt) const;
316     UDate getTransitionTime(Transition* transition, UBool local,
317         int32_t NonExistingTimeOpt, int32_t DuplicatedTimeOpt) const;
318     void getOffsetInternal(UDate date, UBool local, int32_t NonExistingTimeOpt, int32_t DuplicatedTimeOpt,
319         int32_t& rawOffset, int32_t& dstOffset, UErrorCode& ec) const;
320     void completeConst(UErrorCode &status) const;
321 
322     InitialTimeZoneRule *fInitialRule;
323     UVector             *fHistoricRules;
324     UVector             *fFinalRules;
325     UVector             *fHistoricTransitions;
326     UBool               fUpToDate;
327 
328 public:
329     /**
330      * Return the class ID for this class. This is useful only for comparing to
331      * a return value from getDynamicClassID(). For example:
332      * <pre>
333      * .   Base* polymorphic_pointer = createPolymorphicObject();
334      * .   if (polymorphic_pointer->getDynamicClassID() ==
335      * .       erived::getStaticClassID()) ...
336      * </pre>
337      * @return          The class ID for all objects of this class.
338      * @stable ICU 3.8
339      */
340     static UClassID U_EXPORT2 getStaticClassID(void);
341 
342     /**
343      * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. This
344      * method is to implement a simple version of RTTI, since not all C++
345      * compilers support genuine RTTI. Polymorphic operator==() and clone()
346      * methods call this method.
347      *
348      * @return          The class ID for this object. All objects of a
349      *                  given class have the same class ID.  Objects of
350      *                  other classes have different class IDs.
351      * @stable ICU 3.8
352      */
353     virtual UClassID getDynamicClassID(void) const;
354 };
355 
356 U_NAMESPACE_END
357 
358 #endif /* #if !UCONFIG_NO_FORMATTING */
359 
360 #endif // RBTZ_H
361 
362 //eof
363