xref: /aosp_15_r20/external/icu/libicu/cts_headers/unicode/dtitvfmt.h (revision 0e209d3975ff4a8c132096b14b0e9364a753506e)
1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /********************************************************************************
4 * Copyright (C) 2008-2016, International Business Machines Corporation and
5 * others. All Rights Reserved.
6 *******************************************************************************
7 *
8 * File DTITVFMT.H
9 *
10 *******************************************************************************
11 */
12 
13 #ifndef __DTITVFMT_H__
14 #define __DTITVFMT_H__
15 
16 
17 #include "unicode/utypes.h"
18 
19 #if U_SHOW_CPLUSPLUS_API
20 
21 /**
22  * \file
23  * \brief C++ API: Format and parse date interval in a language-independent manner.
24  */
25 
26 #if !UCONFIG_NO_FORMATTING
27 
28 #include "unicode/ucal.h"
29 #include "unicode/smpdtfmt.h"
30 #include "unicode/dtintrv.h"
31 #include "unicode/dtitvinf.h"
32 #include "unicode/dtptngen.h"
33 #include "unicode/formattedvalue.h"
34 #include "unicode/udisplaycontext.h"
35 
36 U_NAMESPACE_BEGIN
37 
38 
39 class FormattedDateIntervalData;
40 class DateIntervalFormat;
41 
42 /**
43  * An immutable class containing the result of a date interval formatting operation.
44  *
45  * Instances of this class are immutable and thread-safe.
46  *
47  * When calling nextPosition():
48  * The fields are returned from left to right. The special field category
49  * UFIELD_CATEGORY_DATE_INTERVAL_SPAN is used to indicate which datetime
50  * primitives came from which arguments: 0 means fromCalendar, and 1 means
51  * toCalendar. The span category will always occur before the
52  * corresponding fields in UFIELD_CATEGORY_DATE
53  * in the nextPosition() iterator.
54  *
55  * Not intended for public subclassing.
56  *
57  * @stable ICU 64
58  */
59 class U_I18N_API FormattedDateInterval : public UMemory, public FormattedValue {
60   public:
61     /**
62      * Default constructor; makes an empty FormattedDateInterval.
63      * @stable ICU 64
64      */
FormattedDateInterval()65     FormattedDateInterval() : fData(nullptr), fErrorCode(U_INVALID_STATE_ERROR) {}
66 
67     /**
68      * Move constructor: Leaves the source FormattedDateInterval in an undefined state.
69      * @stable ICU 64
70      */
71     FormattedDateInterval(FormattedDateInterval&& src) noexcept;
72 
73     /**
74      * Destruct an instance of FormattedDateInterval.
75      * @stable ICU 64
76      */
77     virtual ~FormattedDateInterval() override;
78 
79     /** Copying not supported; use move constructor instead. */
80     FormattedDateInterval(const FormattedDateInterval&) = delete;
81 
82     /** Copying not supported; use move assignment instead. */
83     FormattedDateInterval& operator=(const FormattedDateInterval&) = delete;
84 
85     /**
86      * Move assignment: Leaves the source FormattedDateInterval in an undefined state.
87      * @stable ICU 64
88      */
89     FormattedDateInterval& operator=(FormattedDateInterval&& src) noexcept;
90 
91     /** @copydoc FormattedValue::toString() */
92     UnicodeString toString(UErrorCode& status) const override;
93 
94     /** @copydoc FormattedValue::toTempString() */
95     UnicodeString toTempString(UErrorCode& status) const override;
96 
97     /** @copydoc FormattedValue::appendTo() */
98     Appendable &appendTo(Appendable& appendable, UErrorCode& status) const override;
99 
100     /** @copydoc FormattedValue::nextPosition() */
101     UBool nextPosition(ConstrainedFieldPosition& cfpos, UErrorCode& status) const override;
102 
103   private:
104     FormattedDateIntervalData *fData;
105     UErrorCode fErrorCode;
FormattedDateInterval(FormattedDateIntervalData * results)106     explicit FormattedDateInterval(FormattedDateIntervalData *results)
107         : fData(results), fErrorCode(U_ZERO_ERROR) {}
FormattedDateInterval(UErrorCode errorCode)108     explicit FormattedDateInterval(UErrorCode errorCode)
109         : fData(nullptr), fErrorCode(errorCode) {}
110     friend class DateIntervalFormat;
111 };
112 
113 
114 /**
115  * DateIntervalFormat is a class for formatting and parsing date
116  * intervals in a language-independent manner.
117  * Only formatting is supported, parsing is not supported.
118  *
119  * <P>
120  * Date interval means from one date to another date,
121  * for example, from "Jan 11, 2008" to "Jan 18, 2008".
122  * We introduced class DateInterval to represent it.
123  * DateInterval is a pair of UDate, which is
124  * the standard milliseconds since 24:00 GMT, Jan 1, 1970.
125  *
126  * <P>
127  * DateIntervalFormat formats a DateInterval into
128  * text as compactly as possible.
129  * For example, the date interval format from "Jan 11, 2008" to "Jan 18,. 2008"
130  * is "Jan 11-18, 2008" for English.
131  * And it parses text into DateInterval,
132  * although initially, parsing is not supported.
133  *
134  * <P>
135  * There is no structural information in date time patterns.
136  * For any punctuations and string literals inside a date time pattern,
137  * we do not know whether it is just a separator, or a prefix, or a suffix.
138  * Without such information, so, it is difficult to generate a sub-pattern
139  * (or super-pattern) by algorithm.
140  * So, formatting a DateInterval is pattern-driven. It is very
141  * similar to formatting in SimpleDateFormat.
142  * We introduce class DateIntervalInfo to save date interval
143  * patterns, similar to date time pattern in SimpleDateFormat.
144  *
145  * <P>
146  * Logically, the interval patterns are mappings
147  * from (skeleton, the_largest_different_calendar_field)
148  * to (date_interval_pattern).
149  *
150  * <P>
151  * A skeleton
152  * <ol>
153  * <li>
154  * only keeps the field pattern letter and ignores all other parts
155  * in a pattern, such as space, punctuations, and string literals.
156  * </li>
157  * <li>
158  * hides the order of fields.
159  * </li>
160  * <li>
161  * might hide a field's pattern letter length.
162  * </li>
163  * </ol>
164  *
165  * For those non-digit calendar fields, the pattern letter length is
166  * important, such as MMM, MMMM, and MMMMM; EEE and EEEE,
167  * and the field's pattern letter length is honored.
168  *
169  * For the digit calendar fields,  such as M or MM, d or dd, yy or yyyy,
170  * the field pattern length is ignored and the best match, which is defined
171  * in date time patterns, will be returned without honor the field pattern
172  * letter length in skeleton.
173  *
174  * <P>
175  * The calendar fields we support for interval formatting are:
176  * year, month, date, day-of-week, am-pm, hour, hour-of-day, minute, second,
177  * and millisecond.
178  * (though we do not currently have specific intervalFormat date for skeletons
179  * with seconds and millisecond).
180  * Those calendar fields can be defined in the following order:
181  * year >  month > date > hour (in day) >  minute > second > millisecond
182  *
183  * The largest different calendar fields between 2 calendars is the
184  * first different calendar field in above order.
185  *
186  * For example: the largest different calendar fields between "Jan 10, 2007"
187  * and "Feb 20, 2008" is year.
188  *
189  * <P>
190  * For other calendar fields, the compact interval formatting is not
191  * supported. And the interval format will be fall back to fall-back
192  * patterns, which is mostly "{date0} - {date1}".
193  *
194  * <P>
195  * There is a set of pre-defined static skeleton strings.
196  * There are pre-defined interval patterns for those pre-defined skeletons
197  * in locales' resource files.
198  * For example, for a skeleton UDAT_YEAR_ABBR_MONTH_DAY, which is  &quot;yMMMd&quot;,
199  * in  en_US, if the largest different calendar field between date1 and date2
200  * is &quot;year&quot;, the date interval pattern  is &quot;MMM d, yyyy - MMM d, yyyy&quot;,
201  * such as &quot;Jan 10, 2007 - Jan 10, 2008&quot;.
202  * If the largest different calendar field between date1 and date2 is &quot;month&quot;,
203  * the date interval pattern is &quot;MMM d - MMM d, yyyy&quot;,
204  * such as &quot;Jan 10 - Feb 10, 2007&quot;.
205  * If the largest different calendar field between date1 and date2 is &quot;day&quot;,
206  * the date interval pattern is &quot;MMM d-d, yyyy&quot;, such as &quot;Jan 10-20, 2007&quot;.
207  *
208  * For date skeleton, the interval patterns when year, or month, or date is
209  * different are defined in resource files.
210  * For time skeleton, the interval patterns when am/pm, or hour, or minute is
211  * different are defined in resource files.
212  *
213  * <P>
214  * If a skeleton is not found in a locale's DateIntervalInfo, which means
215  * the interval patterns for the skeleton is not defined in resource file,
216  * the interval pattern will falls back to the interval "fallback" pattern
217  * defined in resource file.
218  * If the interval "fallback" pattern is not defined, the default fall-back
219  * is "{date0} - {data1}".
220  *
221  * <P>
222  * For the combination of date and time,
223  * The rule to generate interval patterns are:
224  * <ol>
225  * <li>
226  *    when the year, month, or day differs, falls back to fall-back
227  *    interval pattern, which mostly is the concatenate the two original
228  *    expressions with a separator between,
229  *    For example, interval pattern from "Jan 10, 2007 10:10 am"
230  *    to "Jan 11, 2007 10:10am" is
231  *    "Jan 10, 2007 10:10 am - Jan 11, 2007 10:10am"
232  * </li>
233  * <li>
234  *    otherwise, present the date followed by the range expression
235  *    for the time.
236  *    For example, interval pattern from "Jan 10, 2007 10:10 am"
237  *    to "Jan 10, 2007 11:10am" is "Jan 10, 2007 10:10 am - 11:10am"
238  * </li>
239  * </ol>
240  *
241  *
242  * <P>
243  * If two dates are the same, the interval pattern is the single date pattern.
244  * For example, interval pattern from "Jan 10, 2007" to "Jan 10, 2007" is
245  * "Jan 10, 2007".
246  *
247  * Or if the presenting fields between 2 dates have the exact same values,
248  * the interval pattern is the  single date pattern.
249  * For example, if user only requests year and month,
250  * the interval pattern from "Jan 10, 2007" to "Jan 20, 2007" is "Jan 2007".
251  *
252  * <P>
253  * DateIntervalFormat needs the following information for correct
254  * formatting: time zone, calendar type, pattern, date format symbols,
255  * and date interval patterns.
256  * It can be instantiated in 2 ways:
257  * <ol>
258  * <li>
259  *    create an instance using default or given locale plus given skeleton.
260  *    Users are encouraged to created date interval formatter this way and
261  *    to use the pre-defined skeleton macros, such as
262  *    UDAT_YEAR_NUM_MONTH, which consists the calendar fields and
263  *    the format style.
264  * </li>
265  * <li>
266  *    create an instance using default or given locale plus given skeleton
267  *    plus a given DateIntervalInfo.
268  *    This factory method is for powerful users who want to provide their own
269  *    interval patterns.
270  *    Locale provides the timezone, calendar, and format symbols information.
271  *    Local plus skeleton provides full pattern information.
272  *    DateIntervalInfo provides the date interval patterns.
273  * </li>
274  * </ol>
275  *
276  * <P>
277  * For the calendar field pattern letter, such as G, y, M, d, a, h, H, m, s etc.
278  * DateIntervalFormat uses the same syntax as that of
279  * DateTime format.
280  *
281  * <P>
282  * Code Sample: general usage
283  * <pre>
284  * \code
285  *   // the date interval object which the DateIntervalFormat formats on
286  *   // and parses into
287  *   DateInterval*  dtInterval = new DateInterval(1000*3600*24, 1000*3600*24*2);
288  *   UErrorCode status = U_ZERO_ERROR;
289  *   DateIntervalFormat* dtIntervalFmt = DateIntervalFormat::createInstance(
290  *                           UDAT_YEAR_MONTH_DAY,
291  *                           Locale("en", "GB", ""), status);
292  *   UnicodeUnicodeString dateIntervalString;
293  *   FieldPosition pos = 0;
294  *   // formatting
295  *   dtIntervalFmt->format(dtInterval, dateIntervalUnicodeString, pos, status);
296  *   delete dtIntervalFmt;
297  * \endcode
298  * </pre>
299  */
300 class U_I18N_API DateIntervalFormat : public Format {
301 public:
302 
303     /**
304      * Construct a DateIntervalFormat from skeleton and  the default locale.
305      *
306      * This is a convenient override of
307      * createInstance(const UnicodeString& skeleton, const Locale& locale,
308      *                UErrorCode&)
309      * with the value of locale as default locale.
310      *
311      * @param skeleton  the skeleton on which interval format based.
312      * @param status    output param set to success/failure code on exit
313      * @return          a date time interval formatter which the caller owns.
314      * @stable ICU 4.0
315      */
316     static DateIntervalFormat* U_EXPORT2 createInstance(
317                                                const UnicodeString& skeleton,
318                                                UErrorCode& status);
319 
320     /**
321      * Construct a DateIntervalFormat from skeleton and a given locale.
322      * <P>
323      * In this factory method,
324      * the date interval pattern information is load from resource files.
325      * Users are encouraged to created date interval formatter this way and
326      * to use the pre-defined skeleton macros.
327      *
328      * <P>
329      * There are pre-defined skeletons (defined in udate.h) having predefined
330      * interval patterns in resource files.
331      * Users are encouraged to use those macros.
332      * For example:
333      * DateIntervalFormat::createInstance(UDAT_MONTH_DAY, status)
334      *
335      * The given Locale provides the interval patterns.
336      * For example, for en_GB, if skeleton is UDAT_YEAR_ABBR_MONTH_WEEKDAY_DAY,
337      * which is "yMMMEEEd",
338      * the interval patterns defined in resource file to above skeleton are:
339      * "EEE, d MMM, yyyy - EEE, d MMM, yyyy" for year differs,
340      * "EEE, d MMM - EEE, d MMM, yyyy" for month differs,
341      * "EEE, d - EEE, d MMM, yyyy" for day differs,
342      * @param skeleton  the skeleton on which the interval format is based.
343      * @param locale    the given locale
344      * @param status    output param set to success/failure code on exit
345      * @return          a date time interval formatter which the caller owns.
346      * @stable ICU 4.0
347      */
348 
349     static DateIntervalFormat* U_EXPORT2 createInstance(
350                                                const UnicodeString& skeleton,
351                                                const Locale& locale,
352                                                UErrorCode& status);
353 
354     /**
355      * Construct a DateIntervalFormat from skeleton
356      *  DateIntervalInfo, and default locale.
357      *
358      * This is a convenient override of
359      * createInstance(const UnicodeString& skeleton, const Locale& locale,
360      *                const DateIntervalInfo& dtitvinf, UErrorCode&)
361      * with the locale value as default locale.
362      *
363      * @param skeleton  the skeleton on which interval format based.
364      * @param dtitvinf  the DateIntervalInfo object.
365      * @param status    output param set to success/failure code on exit
366      * @return          a date time interval formatter which the caller owns.
367      * @stable ICU 4.0
368      */
369     static DateIntervalFormat* U_EXPORT2 createInstance(
370                                               const UnicodeString& skeleton,
371                                               const DateIntervalInfo& dtitvinf,
372                                               UErrorCode& status);
373 
374     /**
375      * Construct a DateIntervalFormat from skeleton
376      * a DateIntervalInfo, and the given locale.
377      *
378      * <P>
379      * In this factory method, user provides its own date interval pattern
380      * information, instead of using those pre-defined data in resource file.
381      * This factory method is for powerful users who want to provide their own
382      * interval patterns.
383      * <P>
384      * There are pre-defined skeletons (defined in udate.h) having predefined
385      * interval patterns in resource files.
386      * Users are encouraged to use those macros.
387      * For example:
388      * DateIntervalFormat::createInstance(UDAT_MONTH_DAY, status)
389      *
390      * The DateIntervalInfo provides the interval patterns.
391      * and the DateIntervalInfo ownership remains to the caller.
392      *
393      * User are encouraged to set default interval pattern in DateIntervalInfo
394      * as well, if they want to set other interval patterns ( instead of
395      * reading the interval patterns from resource files).
396      * When the corresponding interval pattern for a largest calendar different
397      * field is not found ( if user not set it ), interval format fallback to
398      * the default interval pattern.
399      * If user does not provide default interval pattern, it fallback to
400      * "{date0} - {date1}"
401      *
402      * @param skeleton  the skeleton on which interval format based.
403      * @param locale    the given locale
404      * @param dtitvinf  the DateIntervalInfo object.
405      * @param status    output param set to success/failure code on exit
406      * @return          a date time interval formatter which the caller owns.
407      * @stable ICU 4.0
408      */
409     static DateIntervalFormat* U_EXPORT2 createInstance(
410                                               const UnicodeString& skeleton,
411                                               const Locale& locale,
412                                               const DateIntervalInfo& dtitvinf,
413                                               UErrorCode& status);
414 
415     /**
416      * Destructor.
417      * @stable ICU 4.0
418      */
419     virtual ~DateIntervalFormat();
420 
421     /**
422      * Clone this Format object polymorphically. The caller owns the result and
423      * should delete it when done.
424      * @return    A copy of the object.
425      * @stable ICU 4.0
426      */
427     virtual DateIntervalFormat* clone() const override;
428 
429     /**
430      * Return true if the given Format objects are semantically equal. Objects
431      * of different subclasses are considered unequal.
432      * @param other    the object to be compared with.
433      * @return         true if the given Format objects are semantically equal.
434      * @stable ICU 4.0
435      */
436     virtual bool operator==(const Format& other) const override;
437 
438     /**
439      * Return true if the given Format objects are not semantically equal.
440      * Objects of different subclasses are considered unequal.
441      * @param other the object to be compared with.
442      * @return      true if the given Format objects are not semantically equal.
443      * @stable ICU 4.0
444      */
445     bool operator!=(const Format& other) const;
446 
447 
448     using Format::format;
449 
450     /**
451      * Format an object to produce a string. This method handles Formattable
452      * objects with a DateInterval type.
453      * If a the Formattable object type is not a DateInterval,
454      * then it returns a failing UErrorCode.
455      *
456      * @param obj               The object to format.
457      *                          Must be a DateInterval.
458      * @param appendTo          Output parameter to receive result.
459      *                          Result is appended to existing contents.
460      * @param fieldPosition     On input: an alignment field, if desired.
461      *                          On output: the offsets of the alignment field.
462      *                          There may be multiple instances of a given field type
463      *                          in an interval format; in this case the fieldPosition
464      *                          offsets refer to the first instance.
465      * @param status            Output param filled with success/failure status.
466      * @return                  Reference to 'appendTo' parameter.
467      * @stable ICU 4.0
468      */
469     virtual UnicodeString& format(const Formattable& obj,
470                                   UnicodeString& appendTo,
471                                   FieldPosition& fieldPosition,
472                                   UErrorCode& status) const override;
473 
474 
475 
476     /**
477      * Format a DateInterval to produce a string.
478      *
479      * @param dtInterval        DateInterval to be formatted.
480      * @param appendTo          Output parameter to receive result.
481      *                          Result is appended to existing contents.
482      * @param fieldPosition     On input: an alignment field, if desired.
483      *                          On output: the offsets of the alignment field.
484      *                          There may be multiple instances of a given field type
485      *                          in an interval format; in this case the fieldPosition
486      *                          offsets refer to the first instance.
487      * @param status            Output param filled with success/failure status.
488      * @return                  Reference to 'appendTo' parameter.
489      * @stable ICU 4.0
490      */
491     UnicodeString& format(const DateInterval* dtInterval,
492                           UnicodeString& appendTo,
493                           FieldPosition& fieldPosition,
494                           UErrorCode& status) const ;
495 
496     /**
497      * Format a DateInterval to produce a FormattedDateInterval.
498      *
499      * The FormattedDateInterval exposes field information about the formatted string.
500      *
501      * @param dtInterval        DateInterval to be formatted.
502      * @param status            Set if an error occurs.
503      * @return                  A FormattedDateInterval containing the format result.
504      * @stable ICU 64
505      */
506     FormattedDateInterval formatToValue(
507         const DateInterval& dtInterval,
508         UErrorCode& status) const;
509 
510     /**
511      * Format 2 Calendars to produce a string.
512      *
513      * Note: "fromCalendar" and "toCalendar" are not const,
514      * since calendar is not const in  SimpleDateFormat::format(Calendar&),
515      *
516      * @param fromCalendar      calendar set to the from date in date interval
517      *                          to be formatted into date interval string
518      * @param toCalendar        calendar set to the to date in date interval
519      *                          to be formatted into date interval string
520      * @param appendTo          Output parameter to receive result.
521      *                          Result is appended to existing contents.
522      * @param fieldPosition     On input: an alignment field, if desired.
523      *                          On output: the offsets of the alignment field.
524      *                          There may be multiple instances of a given field type
525      *                          in an interval format; in this case the fieldPosition
526      *                          offsets refer to the first instance.
527      * @param status            Output param filled with success/failure status.
528      *                          Caller needs to make sure it is SUCCESS
529      *                          at the function entrance
530      * @return                  Reference to 'appendTo' parameter.
531      * @stable ICU 4.0
532      */
533     UnicodeString& format(Calendar& fromCalendar,
534                           Calendar& toCalendar,
535                           UnicodeString& appendTo,
536                           FieldPosition& fieldPosition,
537                           UErrorCode& status) const ;
538 
539     /**
540      * Format 2 Calendars to produce a FormattedDateInterval.
541      *
542      * The FormattedDateInterval exposes field information about the formatted string.
543      *
544      * Note: "fromCalendar" and "toCalendar" are not const,
545      * since calendar is not const in  SimpleDateFormat::format(Calendar&),
546      *
547      * @param fromCalendar      calendar set to the from date in date interval
548      *                          to be formatted into date interval string
549      * @param toCalendar        calendar set to the to date in date interval
550      *                          to be formatted into date interval string
551      * @param status            Set if an error occurs.
552      * @return                  A FormattedDateInterval containing the format result.
553      * @stable ICU 64
554      */
555     FormattedDateInterval formatToValue(
556         Calendar& fromCalendar,
557         Calendar& toCalendar,
558         UErrorCode& status) const;
559 
560     /**
561      * Date interval parsing is not supported. Please do not use.
562      * <P>
563      * This method should handle parsing of
564      * date time interval strings into Formattable objects with
565      * DateInterval type, which is a pair of UDate.
566      * <P>
567      * Before calling, set parse_pos.index to the offset you want to start
568      * parsing at in the source. After calling, parse_pos.index is the end of
569      * the text you parsed. If error occurs, index is unchanged.
570      * <P>
571      * When parsing, leading whitespace is discarded (with a successful parse),
572      * while trailing whitespace is left as is.
573      * <P>
574      * See Format::parseObject() for more.
575      *
576      * @param source    The string to be parsed into an object.
577      * @param result    Formattable to be set to the parse result.
578      *                  If parse fails, return contents are undefined.
579      * @param parse_pos The position to start parsing at. Since no parsing
580      *                  is supported, upon return this param is unchanged.
581      * @return          A newly created Formattable* object, or nullptr
582      *                  on failure.  The caller owns this and should
583      *                  delete it when done.
584      * @internal ICU 4.0
585      */
586     virtual void parseObject(const UnicodeString& source,
587                              Formattable& result,
588                              ParsePosition& parse_pos) const override;
589 
590 
591     /**
592      * Gets the date time interval patterns.
593      * @return the date time interval patterns associated with
594      * this date interval formatter.
595      * @stable ICU 4.0
596      */
597     const DateIntervalInfo* getDateIntervalInfo() const;
598 
599     /**
600      * Set the date time interval patterns.
601      * @param newIntervalPatterns   the given interval patterns to copy.
602      * @param status          output param set to success/failure code on exit
603      * @stable ICU 4.0
604      */
605     void setDateIntervalInfo(const DateIntervalInfo& newIntervalPatterns,
606                              UErrorCode& status);
607 
608 
609     /**
610      * Gets the date formatter. The DateIntervalFormat instance continues to own
611      * the returned DateFormatter object, and will use and possibly modify it
612      * during format operations. In a multi-threaded environment, the returned
613      * DateFormat can only be used if it is certain that no other threads are
614      * concurrently using this DateIntervalFormatter, even for nominally const
615      * functions.
616      *
617      * @return the date formatter associated with this date interval formatter.
618      * @stable ICU 4.0
619      */
620     const DateFormat* getDateFormat() const;
621 
622     /**
623      * Returns a reference to the TimeZone used by this DateIntervalFormat's calendar.
624      * @return the time zone associated with the calendar of DateIntervalFormat.
625      * @stable ICU 4.8
626      */
627     virtual const TimeZone& getTimeZone() const;
628 
629     /**
630      * Sets the time zone for the calendar used by this DateIntervalFormat object. The
631      * caller no longer owns the TimeZone object and should not delete it after this call.
632      * @param zoneToAdopt the TimeZone to be adopted.
633      * @stable ICU 4.8
634      */
635     virtual void adoptTimeZone(TimeZone* zoneToAdopt);
636 
637     /**
638      * Sets the time zone for the calendar used by this DateIntervalFormat object.
639      * @param zone the new time zone.
640      * @stable ICU 4.8
641      */
642     virtual void setTimeZone(const TimeZone& zone);
643 
644     /**
645      * Set a particular UDisplayContext value in the formatter, such as
646      * UDISPCTX_CAPITALIZATION_FOR_STANDALONE. This causes the formatted
647      * result to be capitalized appropriately for the context in which
648      * it is intended to be used, considering both the locale and the
649      * type of field at the beginning of the formatted result.
650      * @param value The UDisplayContext value to set.
651      * @param status Input/output status. If at entry this indicates a failure
652      *               status, the function will do nothing; otherwise this will be
653      *               updated with any new status from the function.
654      * @stable ICU 68
655      */
656     virtual void setContext(UDisplayContext value, UErrorCode& status);
657 
658     /**
659      * Get the formatter's UDisplayContext value for the specified UDisplayContextType,
660      * such as UDISPCTX_TYPE_CAPITALIZATION.
661      * @param type The UDisplayContextType whose value to return
662      * @param status Input/output status. If at entry this indicates a failure
663      *               status, the function will do nothing; otherwise this will be
664      *               updated with any new status from the function.
665      * @return The UDisplayContextValue for the specified type.
666      * @stable ICU 68
667      */
668     virtual UDisplayContext getContext(UDisplayContextType type, UErrorCode& status) const;
669 
670     /**
671      * Return the class ID for this class. This is useful only for comparing to
672      * a return value from getDynamicClassID(). For example:
673      * <pre>
674      * .   Base* polymorphic_pointer = createPolymorphicObject();
675      * .   if (polymorphic_pointer->getDynamicClassID() ==
676      * .       erived::getStaticClassID()) ...
677      * </pre>
678      * @return          The class ID for all objects of this class.
679      * @stable ICU 4.0
680      */
681     static UClassID U_EXPORT2 getStaticClassID();
682 
683     /**
684      * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. This
685      * method is to implement a simple version of RTTI, since not all C++
686      * compilers support genuine RTTI. Polymorphic operator==() and clone()
687      * methods call this method.
688      *
689      * @return          The class ID for this object. All objects of a
690      *                  given class have the same class ID.  Objects of
691      *                  other classes have different class IDs.
692      * @stable ICU 4.0
693      */
694     virtual UClassID getDynamicClassID() const override;
695 
696 protected:
697 
698     /**
699      * Copy constructor.
700      * @stable ICU 4.0
701      */
702     DateIntervalFormat(const DateIntervalFormat&);
703 
704     /**
705      * Assignment operator.
706      * @stable ICU 4.0
707      */
708     DateIntervalFormat& operator=(const DateIntervalFormat&);
709 
710 private:
711 
712     /*
713      * This is for ICU internal use only. Please do not use.
714      * Save the interval pattern information.
715      * Interval pattern consists of 2 single date patterns and the separator.
716      * For example, interval pattern "MMM d - MMM d, yyyy" consists
717      * a single date pattern "MMM d", another single date pattern "MMM d, yyyy",
718      * and a separator "-".
719      * The pattern is divided into 2 parts. For above example,
720      * the first part is "MMM d - ", and the second part is "MMM d, yyyy".
721      * Also, the first date appears in an interval pattern could be
722      * the earlier date or the later date.
723      * And such information is saved in the interval pattern as well.
724      */
725     struct PatternInfo {
726         UnicodeString firstPart;
727         UnicodeString secondPart;
728         /**
729          * Whether the first date in interval pattern is later date or not.
730          * Fallback format set the default ordering.
731          * And for a particular interval pattern, the order can be
732          * overridden by prefixing the interval pattern with "latestFirst:" or
733          * "earliestFirst:"
734          * For example, given 2 date, Jan 10, 2007 to Feb 10, 2007.
735          * if the fallback format is "{0} - {1}",
736          * and the pattern is "d MMM - d MMM yyyy", the interval format is
737          * "10 Jan - 10 Feb, 2007".
738          * If the pattern is "latestFirst:d MMM - d MMM yyyy",
739          * the interval format is "10 Feb - 10 Jan, 2007"
740          */
741         UBool         laterDateFirst;
742     };
743 
744 
745     /**
746      * default constructor
747      * @internal (private)
748      */
749     DateIntervalFormat();
750 
751     /**
752      * Construct a DateIntervalFormat from DateFormat,
753      * a DateIntervalInfo, and skeleton.
754      * DateFormat provides the timezone, calendar,
755      * full pattern, and date format symbols information.
756      * It should be a SimpleDateFormat object which
757      * has a pattern in it.
758      * the DateIntervalInfo provides the interval patterns.
759      *
760      * Note: the DateIntervalFormat takes ownership of both
761      * DateFormat and DateIntervalInfo objects.
762      * Caller should not delete them.
763      *
764      * @param locale    the locale of this date interval formatter.
765      * @param dtItvInfo the DateIntervalInfo object to be adopted.
766      * @param skeleton  the skeleton of the date formatter
767      * @param status    output param set to success/failure code on exit
768      */
769     DateIntervalFormat(const Locale& locale, DateIntervalInfo* dtItvInfo,
770                        const UnicodeString* skeleton, UErrorCode& status);
771 
772 
773     /**
774      * Construct a DateIntervalFormat from DateFormat
775      * and a DateIntervalInfo.
776      *
777      * It is a wrapper of the constructor.
778      *
779      * @param locale    the locale of this date interval formatter.
780      * @param dtitvinf  the DateIntervalInfo object to be adopted.
781      * @param skeleton  the skeleton of this formatter.
782      * @param status    Output param set to success/failure code.
783      * @return          a date time interval formatter which the caller owns.
784      */
785     static DateIntervalFormat* U_EXPORT2 create(const Locale& locale,
786                                                 DateIntervalInfo* dtitvinf,
787                                                 const UnicodeString* skeleton,
788                                                 UErrorCode& status);
789 
790     /**
791      *  Below are for generating interval patterns local to the formatter
792      */
793 
794     /** Like fallbackFormat, but only formats the range part of the fallback. */
795     void fallbackFormatRange(
796         Calendar& fromCalendar,
797         Calendar& toCalendar,
798         UnicodeString& appendTo,
799         int8_t& firstIndex,
800         FieldPositionHandler& fphandler,
801         UErrorCode& status) const;
802 
803     /**
804      * Format 2 Calendars using fall-back interval pattern
805      *
806      * The full pattern used in this fall-back format is the
807      * full pattern of the date formatter.
808      *
809      * gFormatterMutex must already be locked when calling this function.
810      *
811      * @param fromCalendar      calendar set to the from date in date interval
812      *                          to be formatted into date interval string
813      * @param toCalendar        calendar set to the to date in date interval
814      *                          to be formatted into date interval string
815      * @param fromToOnSameDay   true iff from and to dates are on the same day
816      *                          (any difference is in ampm/hours or below)
817      * @param appendTo          Output parameter to receive result.
818      *                          Result is appended to existing contents.
819      * @param firstIndex        See formatImpl for more information.
820      * @param fphandler         See formatImpl for more information.
821      * @param status            output param set to success/failure code on exit
822      * @return                  Reference to 'appendTo' parameter.
823      * @internal (private)
824      */
825     UnicodeString& fallbackFormat(Calendar& fromCalendar,
826                                   Calendar& toCalendar,
827                                   UBool fromToOnSameDay,
828                                   UnicodeString& appendTo,
829                                   int8_t& firstIndex,
830                                   FieldPositionHandler& fphandler,
831                                   UErrorCode& status) const;
832 
833 
834 
835     /**
836      * Initialize interval patterns locale to this formatter
837      *
838      * This code is a bit complicated since
839      * 1. the interval patterns saved in resource bundle files are interval
840      *    patterns based on date or time only.
841      *    It does not have interval patterns based on both date and time.
842      *    Interval patterns on both date and time are algorithm generated.
843      *
844      *    For example, it has interval patterns on skeleton "dMy" and "hm",
845      *    but it does not have interval patterns on skeleton "dMyhm".
846      *
847      *    The rule to generate interval patterns for both date and time skeleton are
848      *    1) when the year, month, or day differs, concatenate the two original
849      *    expressions with a separator between,
850      *    For example, interval pattern from "Jan 10, 2007 10:10 am"
851      *    to "Jan 11, 2007 10:10am" is
852      *    "Jan 10, 2007 10:10 am - Jan 11, 2007 10:10am"
853      *
854      *    2) otherwise, present the date followed by the range expression
855      *    for the time.
856      *    For example, interval pattern from "Jan 10, 2007 10:10 am"
857      *    to "Jan 10, 2007 11:10am" is
858      *    "Jan 10, 2007 10:10 am - 11:10am"
859      *
860      * 2. even a pattern does not request a certain calendar field,
861      *    the interval pattern needs to include such field if such fields are
862      *    different between 2 dates.
863      *    For example, a pattern/skeleton is "hm", but the interval pattern
864      *    includes year, month, and date when year, month, and date differs.
865      *
866      *
867      * @param status    output param set to success/failure code on exit
868      */
869     void initializePattern(UErrorCode& status);
870 
871 
872 
873     /**
874      * Set fall back interval pattern given a calendar field,
875      * a skeleton, and a date time pattern generator.
876      * @param field      the largest different calendar field
877      * @param skeleton   a skeleton
878      * @param status     output param set to success/failure code on exit
879      */
880     void setFallbackPattern(UCalendarDateFields field,
881                             const UnicodeString& skeleton,
882                             UErrorCode& status);
883 
884 
885 
886     /**
887      * Converts special hour metacharacters (such as 'j') in the skeleton into locale-appropriate
888      * pattern characters.
889      *
890      *
891      *  @param skeleton               The skeleton to convert
892      *  @return A copy of the skeleton, which "j" and any other special hour metacharacters converted to the regular ones.
893      *
894      */
895     UnicodeString normalizeHourMetacharacters(const UnicodeString& skeleton) const;
896 
897 
898 
899     /**
900      * get separated date and time skeleton from a combined skeleton.
901      *
902      * The difference between date skeleton and normalizedDateSkeleton are:
903      * 1. both 'y' and 'd' are appeared only once in normalizeDateSkeleton
904      * 2. 'E' and 'EE' are normalized into 'EEE'
905      * 3. 'MM' is normalized into 'M'
906      *
907      ** the difference between time skeleton and normalizedTimeSkeleton are:
908      * 1. both 'H' and 'h' are normalized as 'h' in normalized time skeleton,
909      * 2. 'a' is omitted in normalized time skeleton.
910      * 3. there is only one appearance for 'h', 'm','v', 'z' in normalized time
911      *    skeleton
912      *
913      *
914      *  @param skeleton               given combined skeleton.
915      *  @param date                   Output parameter for date only skeleton.
916      *  @param normalizedDate         Output parameter for normalized date only
917      *
918      *  @param time                   Output parameter for time only skeleton.
919      *  @param normalizedTime         Output parameter for normalized time only
920      *                                skeleton.
921      *
922      */
923     static void  U_EXPORT2 getDateTimeSkeleton(const UnicodeString& skeleton,
924                                     UnicodeString& date,
925                                     UnicodeString& normalizedDate,
926                                     UnicodeString& time,
927                                     UnicodeString& normalizedTime);
928 
929 
930 
931     /**
932      * Generate date or time interval pattern from resource,
933      * and set them into the interval pattern locale to this formatter.
934      *
935      * It needs to handle the following:
936      * 1. need to adjust field width.
937      *    For example, the interval patterns saved in DateIntervalInfo
938      *    includes "dMMMy", but not "dMMMMy".
939      *    Need to get interval patterns for dMMMMy from dMMMy.
940      *    Another example, the interval patterns saved in DateIntervalInfo
941      *    includes "hmv", but not "hmz".
942      *    Need to get interval patterns for "hmz' from 'hmv'
943      *
944      * 2. there might be no pattern for 'y' differ for skeleton "Md",
945      *    in order to get interval patterns for 'y' differ,
946      *    need to look for it from skeleton 'yMd'
947      *
948      * @param dateSkeleton   normalized date skeleton
949      * @param timeSkeleton   normalized time skeleton
950      * @return               whether the resource is found for the skeleton.
951      *                       true if interval pattern found for the skeleton,
952      *                       false otherwise.
953      */
954     UBool setSeparateDateTimePtn(const UnicodeString& dateSkeleton,
955                                  const UnicodeString& timeSkeleton);
956 
957 
958 
959 
960     /**
961      * Generate interval pattern from existing resource
962      *
963      * It not only save the interval patterns,
964      * but also return the extended skeleton and its best match skeleton.
965      *
966      * @param field           largest different calendar field
967      * @param skeleton        skeleton
968      * @param bestSkeleton    the best match skeleton which has interval pattern
969      *                        defined in resource
970      * @param differenceInfo  the difference between skeleton and best skeleton
971      *         0 means the best matched skeleton is the same as input skeleton
972      *         1 means the fields are the same, but field width are different
973      *         2 means the only difference between fields are v/z,
974      *        -1 means there are other fields difference
975      *
976      * @param extendedSkeleton      extended skeleton
977      * @param extendedBestSkeleton  extended best match skeleton
978      * @return                      whether the interval pattern is found
979      *                              through extending skeleton or not.
980      *                              true if interval pattern is found by
981      *                              extending skeleton, false otherwise.
982      */
983     UBool setIntervalPattern(UCalendarDateFields field,
984                              const UnicodeString* skeleton,
985                              const UnicodeString* bestSkeleton,
986                              int8_t differenceInfo,
987                              UnicodeString* extendedSkeleton = nullptr,
988                              UnicodeString* extendedBestSkeleton = nullptr);
989 
990     /**
991      * Adjust field width in best match interval pattern to match
992      * the field width in input skeleton.
993      *
994      * TODO (xji) make a general solution
995      * The adjusting rule can be:
996      * 1. always adjust
997      * 2. never adjust
998      * 3. default adjust, which means adjust according to the following rules
999      * 3.1 always adjust string, such as MMM and MMMM
1000      * 3.2 never adjust between string and numeric, such as MM and MMM
1001      * 3.3 always adjust year
1002      * 3.4 do not adjust 'd', 'h', or 'm' if h presents
1003      * 3.5 do not adjust 'M' if it is numeric(?)
1004      *
1005      * Since date interval format is well-formed format,
1006      * date and time skeletons are normalized previously,
1007      * till this stage, the adjust here is only "adjust strings, such as MMM
1008      * and MMMM, EEE and EEEE.
1009      *
1010      * @param inputSkeleton            the input skeleton
1011      * @param bestMatchSkeleton        the best match skeleton
1012      * @param bestMatchIntervalPattern the best match interval pattern
1013      * @param differenceInfo           the difference between 2 skeletons
1014      *                                 1 means only field width differs
1015      *                                 2 means v/z exchange
1016      * @param suppressDayPeriodField if true, remove the day period field from the pattern, if there is one
1017      * @param adjustedIntervalPattern  adjusted interval pattern
1018      */
1019     static void U_EXPORT2 adjustFieldWidth(
1020                             const UnicodeString& inputSkeleton,
1021                             const UnicodeString& bestMatchSkeleton,
1022                             const UnicodeString& bestMatchIntervalPattern,
1023                             int8_t differenceInfo,
1024                             UBool suppressDayPeriodField,
1025                             UnicodeString& adjustedIntervalPattern);
1026 
1027     /**
1028      * Does the same thing as UnicodeString::findAndReplace(), except that it won't perform
1029      * the substitution inside quoted literal text.
1030      * @param targetString The string to perform the find-replace operation on.
1031      * @param strToReplace The string to search for and replace in the target string.
1032      * @param strToReplaceWith The string to substitute in wherever `stringToReplace` was found.
1033      */
1034     static void U_EXPORT2 findReplaceInPattern(UnicodeString& targetString,
1035                                                const UnicodeString& strToReplace,
1036                                                const UnicodeString& strToReplaceWith);
1037 
1038     /**
1039      * Concat a single date pattern with a time interval pattern,
1040      * set it into the intervalPatterns, while field is time field.
1041      * This is used to handle time interval patterns on skeleton with
1042      * both time and date. Present the date followed by
1043      * the range expression for the time.
1044      * @param format         date and time format
1045      * @param datePattern    date pattern
1046      * @param field          time calendar field: AM_PM, HOUR, MINUTE
1047      * @param status         output param set to success/failure code on exit
1048      */
1049     void concatSingleDate2TimeInterval(UnicodeString& format,
1050                                        const UnicodeString& datePattern,
1051                                        UCalendarDateFields field,
1052                                        UErrorCode& status);
1053 
1054     /**
1055      * check whether a calendar field present in a skeleton.
1056      * @param field      calendar field need to check
1057      * @param skeleton   given skeleton on which to check the calendar field
1058      * @return           true if field present in a skeleton.
1059      */
1060     static UBool U_EXPORT2 fieldExistsInSkeleton(UCalendarDateFields field,
1061                                                  const UnicodeString& skeleton);
1062 
1063 
1064     /**
1065      * Split interval patterns into 2 part.
1066      * @param intervalPattern  interval pattern
1067      * @return the index in interval pattern which split the pattern into 2 part
1068      */
1069     static int32_t  U_EXPORT2 splitPatternInto2Part(const UnicodeString& intervalPattern);
1070 
1071 
1072     /**
1073      * Break interval patterns as 2 part and save them into pattern info.
1074      * @param field            calendar field
1075      * @param intervalPattern  interval pattern
1076      */
1077     void setIntervalPattern(UCalendarDateFields field,
1078                             const UnicodeString& intervalPattern);
1079 
1080 
1081     /**
1082      * Break interval patterns as 2 part and save them into pattern info.
1083      * @param field            calendar field
1084      * @param intervalPattern  interval pattern
1085      * @param laterDateFirst   whether later date appear first in interval pattern
1086      */
1087     void setIntervalPattern(UCalendarDateFields field,
1088                             const UnicodeString& intervalPattern,
1089                             UBool laterDateFirst);
1090 
1091 
1092     /**
1093      * Set pattern information.
1094      *
1095      * @param field            calendar field
1096      * @param firstPart        the first part in interval pattern
1097      * @param secondPart       the second part in interval pattern
1098      * @param laterDateFirst   whether the first date in intervalPattern
1099      *                         is earlier date or later date
1100      */
1101     void setPatternInfo(UCalendarDateFields field,
1102                         const UnicodeString* firstPart,
1103                         const UnicodeString* secondPart,
1104                         UBool laterDateFirst);
1105 
1106     /**
1107      * Format 2 Calendars to produce a string.
1108      * Implementation of the similar public format function.
1109      * Must be called with gFormatterMutex already locked.
1110      *
1111      * Note: "fromCalendar" and "toCalendar" are not const,
1112      * since calendar is not const in  SimpleDateFormat::format(Calendar&),
1113      *
1114      * @param fromCalendar      calendar set to the from date in date interval
1115      *                          to be formatted into date interval string
1116      * @param toCalendar        calendar set to the to date in date interval
1117      *                          to be formatted into date interval string
1118      * @param appendTo          Output parameter to receive result.
1119      *                          Result is appended to existing contents.
1120      * @param firstIndex        0 if the first output date is fromCalendar;
1121      *                          1 if it corresponds to toCalendar;
1122      *                          -1 if there is only one date printed.
1123      * @param fphandler         Handler for field position information.
1124      *                          The fields will be from the UDateFormatField enum.
1125      * @param status            Output param filled with success/failure status.
1126      *                          Caller needs to make sure it is SUCCESS
1127      *                          at the function entrance
1128      * @return                  Reference to 'appendTo' parameter.
1129      * @internal (private)
1130      */
1131     UnicodeString& formatImpl(Calendar& fromCalendar,
1132                               Calendar& toCalendar,
1133                               UnicodeString& appendTo,
1134                               int8_t& firstIndex,
1135                               FieldPositionHandler& fphandler,
1136                               UErrorCode& status) const ;
1137 
1138     /** Version of formatImpl for DateInterval. */
1139     UnicodeString& formatIntervalImpl(const DateInterval& dtInterval,
1140                               UnicodeString& appendTo,
1141                               int8_t& firstIndex,
1142                               FieldPositionHandler& fphandler,
1143                               UErrorCode& status) const;
1144 
1145 
1146     // from calendar field to pattern letter
1147     static const char16_t fgCalendarFieldToPatternLetter[];
1148 
1149 
1150     /**
1151      * The interval patterns for this locale.
1152      */
1153     DateIntervalInfo*     fInfo;
1154 
1155     /**
1156      * The DateFormat object used to format single pattern
1157      */
1158     SimpleDateFormat*     fDateFormat;
1159 
1160     /**
1161      * The 2 calendars with the from and to date.
1162      * could re-use the calendar in fDateFormat,
1163      * but keeping 2 calendars make it clear and clean.
1164      */
1165     Calendar* fFromCalendar;
1166     Calendar* fToCalendar;
1167 
1168     Locale fLocale;
1169 
1170     /**
1171      * Following are interval information relevant (locale) to this formatter.
1172      */
1173     UnicodeString fSkeleton;
1174     PatternInfo fIntervalPatterns[DateIntervalInfo::kIPI_MAX_INDEX];
1175 
1176     /**
1177      * Patterns for fallback formatting.
1178      */
1179     UnicodeString* fDatePattern;
1180     UnicodeString* fTimePattern;
1181     UnicodeString* fDateTimeFormat;
1182 
1183     /**
1184      * Other formatting information
1185      */
1186     UDisplayContext fCapitalizationContext;
1187 };
1188 
1189 inline bool
1190 DateIntervalFormat::operator!=(const Format& other) const  {
1191     return !operator==(other);
1192 }
1193 
1194 U_NAMESPACE_END
1195 
1196 #endif /* #if !UCONFIG_NO_FORMATTING */
1197 
1198 #endif /* U_SHOW_CPLUSPLUS_API */
1199 
1200 #endif // _DTITVFMT_H__
1201 //eof
1202