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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4  ********************************************************************************
5  *   Copyright (C) 1997-2016, International Business Machines
6  *   Corporation and others.  All Rights Reserved.
7  ********************************************************************************
8  *
9  * File DATEFMT.H
10  *
11  * Modification History:
12  *
13  *   Date        Name        Description
14  *   02/19/97    aliu        Converted from java.
15  *   04/01/97    aliu        Added support for centuries.
16  *   07/23/98    stephen     JDK 1.2 sync
17  *   11/15/99    weiv        Added support for week of year/day of week formatting
18  ********************************************************************************
19  */
20 
21 #ifndef DATEFMT_H
22 #define DATEFMT_H
23 
24 #include "unicode/utypes.h"
25 
26 #if U_SHOW_CPLUSPLUS_API
27 
28 #if !UCONFIG_NO_FORMATTING
29 
30 #include "unicode/udat.h"
31 #include "unicode/calendar.h"
32 #include "unicode/numfmt.h"
33 #include "unicode/format.h"
34 #include "unicode/locid.h"
35 #include "unicode/enumset.h"
36 #include "unicode/udisplaycontext.h"
37 
38 /**
39  * \file
40  * \brief C++ API: Abstract class for converting dates.
41  */
42 
43 U_NAMESPACE_BEGIN
44 
45 class TimeZone;
46 class DateTimePatternGenerator;
47 
48 /**
49  * \cond
50  * Export an explicit template instantiation. (See digitlst.h, datefmt.h, and others.)
51  * (When building DLLs for Windows this is required.)
52  */
53 #if U_PF_WINDOWS <= U_PLATFORM && U_PLATFORM <= U_PF_CYGWIN && !defined(U_IN_DOXYGEN)
54 template class U_I18N_API EnumSet<UDateFormatBooleanAttribute,
55             0,
56             UDAT_BOOLEAN_ATTRIBUTE_COUNT>;
57 #endif
58 /** \endcond */
59 
60 /**
61  * DateFormat is an abstract class for a family of classes that convert dates and
62  * times from their internal representations to textual form and back again in a
63  * language-independent manner. Converting from the internal representation (milliseconds
64  * since midnight, January 1, 1970) to text is known as "formatting," and converting
65  * from text to millis is known as "parsing."  We currently define only one concrete
66  * subclass of DateFormat: SimpleDateFormat, which can handle pretty much all normal
67  * date formatting and parsing actions.
68  * <P>
69  * DateFormat helps you to format and parse dates for any locale. Your code can
70  * be completely independent of the locale conventions for months, days of the
71  * week, or even the calendar format: lunar vs. solar.
72  * <P>
73  * To format a date for the current Locale, use one of the static factory
74  * methods:
75  * <pre>
76  * \code
77  *      DateFormat* dfmt = DateFormat::createDateInstance();
78  *      UDate myDate = Calendar::getNow();
79  *      UnicodeString myString;
80  *      myString = dfmt->format( myDate, myString );
81  * \endcode
82  * </pre>
83  * If you are formatting multiple numbers, it is more efficient to get the
84  * format and use it multiple times so that the system doesn't have to fetch the
85  * information about the local language and country conventions multiple times.
86  * <pre>
87  * \code
88  *      DateFormat* df = DateFormat::createDateInstance();
89  *      UnicodeString myString;
90  *      UDate myDateArr[] = { 0.0, 100000000.0, 2000000000.0 }; // test values
91  *      for (int32_t i = 0; i < 3; ++i) {
92  *          myString.remove();
93  *          cout << df->format( myDateArr[i], myString ) << endl;
94  *      }
95  * \endcode
96  * </pre>
97  * To get specific fields of a date, you can use UFieldPosition to
98  * get specific fields.
99  * <pre>
100  * \code
101  *      DateFormat* dfmt = DateFormat::createDateInstance();
102  *      FieldPosition pos(DateFormat::YEAR_FIELD);
103  *      UnicodeString myString;
104  *      myString = dfmt->format( myDate, myString );
105  *      cout << myString << endl;
106  *      cout << pos.getBeginIndex() << "," << pos. getEndIndex() << endl;
107  * \endcode
108  * </pre>
109  * To format a date for a different Locale, specify it in the call to
110  * createDateInstance().
111  * <pre>
112  * \code
113  *       DateFormat* df =
114  *           DateFormat::createDateInstance( DateFormat::SHORT, Locale::getFrance());
115  * \endcode
116  * </pre>
117  * You can use a DateFormat to parse also.
118  * <pre>
119  * \code
120  *       UErrorCode status = U_ZERO_ERROR;
121  *       UDate myDate = df->parse(myString, status);
122  * \endcode
123  * </pre>
124  * Use createDateInstance() to produce the normal date format for that country.
125  * There are other static factory methods available. Use createTimeInstance()
126  * to produce the normal time format for that country. Use createDateTimeInstance()
127  * to produce a DateFormat that formats both date and time. You can pass in
128  * different options to these factory methods to control the length of the
129  * result; from SHORT to MEDIUM to LONG to FULL. The exact result depends on the
130  * locale, but generally:
131  * <ul type=round>
132  *   <li>   SHORT is completely numeric, such as 12/13/52 or 3:30pm
133  *   <li>   MEDIUM is longer, such as Jan 12, 1952
134  *   <li>   LONG is longer, such as January 12, 1952 or 3:30:32pm
135  *   <li>   FULL is pretty completely specified, such as
136  *          Tuesday, April 12, 1952 AD or 3:30:42pm PST.
137  * </ul>
138  * You can also set the time zone on the format if you wish. If you want even
139  * more control over the format or parsing, (or want to give your users more
140  * control), you can try casting the DateFormat you get from the factory methods
141  * to a SimpleDateFormat. This will work for the majority of countries; just
142  * remember to check getDynamicClassID() before carrying out the cast.
143  * <P>
144  * You can also use forms of the parse and format methods with ParsePosition and
145  * FieldPosition to allow you to
146  * <ul type=round>
147  *   <li>   Progressively parse through pieces of a string.
148  *   <li>   Align any particular field, or find out where it is for selection
149  *          on the screen.
150  * </ul>
151  *
152  * <p><em>User subclasses are not supported.</em> While clients may write
153  * subclasses, such code will not necessarily work and will not be
154  * guaranteed to work stably from release to release.
155  */
156 class U_I18N_API DateFormat : public Format {
157 public:
158 
159     /**
160      * Constants for various style patterns. These reflect the order of items in
161      * the DateTimePatterns resource. There are 4 time patterns, 4 date patterns,
162      * the default date-time pattern, and 4 date-time patterns. Each block of 4 values
163      * in the resource occurs in the order full, long, medium, short.
164      * @stable ICU 2.4
165      */
166     enum EStyle
167     {
168         kNone   = -1,
169 
170         kFull   = 0,
171         kLong   = 1,
172         kMedium = 2,
173         kShort  = 3,
174 
175         kDateOffset   = kShort + 1,
176      // kFull   + kDateOffset = 4
177      // kLong   + kDateOffset = 5
178      // kMedium + kDateOffset = 6
179      // kShort  + kDateOffset = 7
180 
181         kDateTime             = 8,
182      // Default DateTime
183 
184         kDateTimeOffset = kDateTime + 1,
185      // kFull   + kDateTimeOffset = 9
186      // kLong   + kDateTimeOffset = 10
187      // kMedium + kDateTimeOffset = 11
188      // kShort  + kDateTimeOffset = 12
189 
190         // relative dates
191         kRelative = (1 << 7),
192 
193         kFullRelative = (kFull | kRelative),
194 
195         kLongRelative = kLong | kRelative,
196 
197         kMediumRelative = kMedium | kRelative,
198 
199         kShortRelative = kShort | kRelative,
200 
201 
202         kDefault      = kMedium,
203 
204 
205 
206     /**
207      * These constants are provided for backwards compatibility only.
208      * Please use the C++ style constants defined above.
209      */
210         FULL        = kFull,
211         LONG        = kLong,
212         MEDIUM        = kMedium,
213         SHORT        = kShort,
214         DEFAULT        = kDefault,
215         DATE_OFFSET    = kDateOffset,
216         NONE        = kNone,
217         DATE_TIME    = kDateTime
218     };
219 
220     /**
221      * Destructor.
222      * @stable ICU 2.0
223      */
224     virtual ~DateFormat();
225 
226     /**
227      * Clones this object polymorphically.
228      * The caller owns the result and should delete it when done.
229      * @return clone, or nullptr if an error occurred
230      * @stable ICU 2.0
231      */
232     virtual DateFormat* clone() const override = 0;
233 
234     /**
235      * Equality operator.  Returns true if the two formats have the same behavior.
236      * @stable ICU 2.0
237      */
238     virtual bool operator==(const Format&) const override;
239 
240 
241     using Format::format;
242 
243     /**
244      * Format an object to produce a string. This method handles Formattable
245      * objects with a UDate type. If a the Formattable object type is not a Date,
246      * then it returns a failing UErrorCode.
247      *
248      * @param obj       The object to format. Must be a Date.
249      * @param appendTo  Output parameter to receive result.
250      *                  Result is appended to existing contents.
251      * @param pos       On input: an alignment field, if desired.
252      *                  On output: the offsets of the alignment field.
253      * @param status    Output param filled with success/failure status.
254      * @return          Reference to 'appendTo' parameter.
255      * @stable ICU 2.0
256      */
257     virtual UnicodeString& format(const Formattable& obj,
258                                   UnicodeString& appendTo,
259                                   FieldPosition& pos,
260                                   UErrorCode& status) const override;
261 
262     /**
263      * Format an object to produce a string. This method handles Formattable
264      * objects with a UDate type. If a the Formattable object type is not a Date,
265      * then it returns a failing UErrorCode.
266      *
267      * @param obj       The object to format. Must be a Date.
268      * @param appendTo  Output parameter to receive result.
269      *                  Result is appended to existing contents.
270      * @param posIter   On return, can be used to iterate over positions
271      *                  of fields generated by this format call.  Field values
272      *                  are defined in UDateFormatField.  Can be NULL.
273      * @param status    Output param filled with success/failure status.
274      * @return          Reference to 'appendTo' parameter.
275      * @stable ICU 4.4
276      */
277     virtual UnicodeString& format(const Formattable& obj,
278                                   UnicodeString& appendTo,
279                                   FieldPositionIterator* posIter,
280                                   UErrorCode& status) const override;
281     /**
282      * Formats a date into a date/time string. This is an abstract method which
283      * concrete subclasses must implement.
284      * <P>
285      * On input, the FieldPosition parameter may have its "field" member filled with
286      * an enum value specifying a field.  On output, the FieldPosition will be filled
287      * in with the text offsets for that field.
288      * <P> For example, given a time text
289      * "1996.07.10 AD at 15:08:56 PDT", if the given fieldPosition.field is
290      * UDAT_YEAR_FIELD, the offsets fieldPosition.beginIndex and
291      * statfieldPositionus.getEndIndex will be set to 0 and 4, respectively.
292      * <P> Notice
293      * that if the same time field appears more than once in a pattern, the status will
294      * be set for the first occurrence of that time field. For instance,
295      * formatting a UDate to the time string "1 PM PDT (Pacific Daylight Time)"
296      * using the pattern "h a z (zzzz)" and the alignment field
297      * DateFormat::TIMEZONE_FIELD, the offsets fieldPosition.beginIndex and
298      * fieldPosition.getEndIndex will be set to 5 and 8, respectively, for the first
299      * occurrence of the timezone pattern character 'z'.
300      *
301      * @param cal           Calendar set to the date and time to be formatted
302      *                      into a date/time string.  When the calendar type is
303      *                      different from the internal calendar held by this
304      *                      DateFormat instance, the date and the time zone will
305      *                      be inherited from the input calendar, but other calendar
306      *                      field values will be calculated by the internal calendar.
307      * @param appendTo      Output parameter to receive result.
308      *                      Result is appended to existing contents.
309      * @param fieldPosition On input: an alignment field, if desired (see examples above)
310      *                      On output: the offsets of the alignment field (see examples above)
311      * @return              Reference to 'appendTo' parameter.
312      * @stable ICU 2.1
313      */
314     virtual UnicodeString& format(  Calendar& cal,
315                                     UnicodeString& appendTo,
316                                     FieldPosition& fieldPosition) const = 0;
317 
318     /**
319      * Formats a date into a date/time string. Subclasses should implement this method.
320      *
321      * @param cal       Calendar set to the date and time to be formatted
322      *                  into a date/time string.  When the calendar type is
323      *                  different from the internal calendar held by this
324      *                  DateFormat instance, the date and the time zone will
325      *                  be inherited from the input calendar, but other calendar
326      *                  field values will be calculated by the internal calendar.
327      * @param appendTo  Output parameter to receive result.
328      *                  Result is appended to existing contents.
329      * @param posIter   On return, can be used to iterate over positions
330      *                  of fields generated by this format call.  Field values
331      *                  are defined in UDateFormatField.  Can be NULL.
332      * @param status    error status.
333      * @return          Reference to 'appendTo' parameter.
334      * @stable ICU 4.4
335      */
336     virtual UnicodeString& format(Calendar& cal,
337                                   UnicodeString& appendTo,
338                                   FieldPositionIterator* posIter,
339                                   UErrorCode& status) const;
340     /**
341      * Formats a UDate into a date/time string.
342      * <P>
343      * On input, the FieldPosition parameter may have its "field" member filled with
344      * an enum value specifying a field.  On output, the FieldPosition will be filled
345      * in with the text offsets for that field.
346      * <P> For example, given a time text
347      * "1996.07.10 AD at 15:08:56 PDT", if the given fieldPosition.field is
348      * UDAT_YEAR_FIELD, the offsets fieldPosition.beginIndex and
349      * statfieldPositionus.getEndIndex will be set to 0 and 4, respectively.
350      * <P> Notice
351      * that if the same time field appears more than once in a pattern, the status will
352      * be set for the first occurrence of that time field. For instance,
353      * formatting a UDate to the time string "1 PM PDT (Pacific Daylight Time)"
354      * using the pattern "h a z (zzzz)" and the alignment field
355      * DateFormat::TIMEZONE_FIELD, the offsets fieldPosition.beginIndex and
356      * fieldPosition.getEndIndex will be set to 5 and 8, respectively, for the first
357      * occurrence of the timezone pattern character 'z'.
358      *
359      * @param date          UDate to be formatted into a date/time string.
360      * @param appendTo      Output parameter to receive result.
361      *                      Result is appended to existing contents.
362      * @param fieldPosition On input: an alignment field, if desired (see examples above)
363      *                      On output: the offsets of the alignment field (see examples above)
364      * @return              Reference to 'appendTo' parameter.
365      * @stable ICU 2.0
366      */
367     UnicodeString& format(  UDate date,
368                             UnicodeString& appendTo,
369                             FieldPosition& fieldPosition) const;
370 
371     /**
372      * Formats a UDate into a date/time string.
373      *
374      * @param date      UDate to be formatted into a date/time string.
375      * @param appendTo  Output parameter to receive result.
376      *                  Result is appended to existing contents.
377      * @param posIter   On return, can be used to iterate over positions
378      *                  of fields generated by this format call.  Field values
379      *                  are defined in UDateFormatField.  Can be NULL.
380      * @param status    error status.
381      * @return          Reference to 'appendTo' parameter.
382      * @stable ICU 4.4
383      */
384     UnicodeString& format(UDate date,
385                           UnicodeString& appendTo,
386                           FieldPositionIterator* posIter,
387                           UErrorCode& status) const;
388     /**
389      * Formats a UDate into a date/time string. If there is a problem, you won't
390      * know, using this method. Use the overloaded format() method which takes a
391      * FieldPosition& to detect formatting problems.
392      *
393      * @param date      The UDate value to be formatted into a string.
394      * @param appendTo  Output parameter to receive result.
395      *                  Result is appended to existing contents.
396      * @return          Reference to 'appendTo' parameter.
397      * @stable ICU 2.0
398      */
399     UnicodeString& format(UDate date, UnicodeString& appendTo) const;
400 
401     /**
402      * Parse a date/time string. For example, a time text "07/10/96 4:5 PM, PDT"
403      * will be parsed into a UDate that is equivalent to Date(837039928046).
404      * Parsing begins at the beginning of the string and proceeds as far as
405      * possible.  Assuming no parse errors were encountered, this function
406      * doesn't return any information about how much of the string was consumed
407      * by the parsing.  If you need that information, use the version of
408      * parse() that takes a ParsePosition.
409      * <P>
410      * By default, parsing is lenient: If the input is not in the form used by
411      * this object's format method but can still be parsed as a date, then the
412      * parse succeeds. Clients may insist on strict adherence to the format by
413      * calling setLenient(false).
414      * @see DateFormat::setLenient(boolean)
415      * <P>
416      * Note that the normal date formats associated with some calendars - such
417      * as the Chinese lunar calendar - do not specify enough fields to enable
418      * dates to be parsed unambiguously. In the case of the Chinese lunar
419      * calendar, while the year within the current 60-year cycle is specified,
420      * the number of such cycles since the start date of the calendar (in the
421      * ERA field of the Calendar object) is not normally part of the format,
422      * and parsing may assume the wrong era. For cases such as this it is
423      * recommended that clients parse using the method
424      * parse(const UnicodeString&, Calendar& cal, ParsePosition&)
425      * with the Calendar passed in set to the current date, or to a date
426      * within the era/cycle that should be assumed if absent in the format.
427      *
428      * @param text      The date/time string to be parsed into a UDate value.
429      * @param status    Output param to be set to success/failure code. If
430      *                  'text' cannot be parsed, it will be set to a failure
431      *                  code.
432      * @return          The parsed UDate value, if successful.
433      * @stable ICU 2.0
434      */
435     virtual UDate parse( const UnicodeString& text,
436                         UErrorCode& status) const;
437 
438     /**
439      * Parse a date/time string beginning at the given parse position. For
440      * example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
441      * that is equivalent to Date(837039928046).
442      * <P>
443      * By default, parsing is lenient: If the input is not in the form used by
444      * this object's format method but can still be parsed as a date, then the
445      * parse succeeds. Clients may insist on strict adherence to the format by
446      * calling setLenient(false).
447      * @see DateFormat::setLenient(boolean)
448      *
449      * @param text  The date/time string to be parsed.
450      * @param cal   A Calendar set on input to the date and time to be used for
451      *              missing values in the date/time string being parsed, and set
452      *              on output to the parsed date/time. When the calendar type is
453      *              different from the internal calendar held by this DateFormat
454      *              instance, the internal calendar will be cloned to a work
455      *              calendar set to the same milliseconds and time zone as the
456      *              cal parameter, field values will be parsed based on the work
457      *              calendar, then the result (milliseconds and time zone) will
458      *              be set in this calendar.
459      * @param pos   On input, the position at which to start parsing; on
460      *              output, the position at which parsing terminated, or the
461      *              start position if the parse failed.
462      * @stable ICU 2.1
463      */
464     virtual void parse( const UnicodeString& text,
465                         Calendar& cal,
466                         ParsePosition& pos) const = 0;
467 
468     /**
469      * Parse a date/time string beginning at the given parse position. For
470      * example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
471      * that is equivalent to Date(837039928046).
472      * <P>
473      * By default, parsing is lenient: If the input is not in the form used by
474      * this object's format method but can still be parsed as a date, then the
475      * parse succeeds. Clients may insist on strict adherence to the format by
476      * calling setLenient(false).
477      * @see DateFormat::setLenient(boolean)
478      * <P>
479      * Note that the normal date formats associated with some calendars - such
480      * as the Chinese lunar calendar - do not specify enough fields to enable
481      * dates to be parsed unambiguously. In the case of the Chinese lunar
482      * calendar, while the year within the current 60-year cycle is specified,
483      * the number of such cycles since the start date of the calendar (in the
484      * ERA field of the Calendar object) is not normally part of the format,
485      * and parsing may assume the wrong era. For cases such as this it is
486      * recommended that clients parse using the method
487      * parse(const UnicodeString&, Calendar& cal, ParsePosition&)
488      * with the Calendar passed in set to the current date, or to a date
489      * within the era/cycle that should be assumed if absent in the format.
490      *
491      * @param text  The date/time string to be parsed into a UDate value.
492      * @param pos   On input, the position at which to start parsing; on
493      *              output, the position at which parsing terminated, or the
494      *              start position if the parse failed.
495      * @return      A valid UDate if the input could be parsed.
496      * @stable ICU 2.0
497      */
498     UDate parse( const UnicodeString& text,
499                  ParsePosition& pos) const;
500 
501     /**
502      * Parse a string to produce an object. This methods handles parsing of
503      * date/time strings into Formattable objects with UDate types.
504      * <P>
505      * Before calling, set parse_pos.index to the offset you want to start
506      * parsing at in the source. After calling, parse_pos.index is the end of
507      * the text you parsed. If error occurs, index is unchanged.
508      * <P>
509      * When parsing, leading whitespace is discarded (with a successful parse),
510      * while trailing whitespace is left as is.
511      * <P>
512      * See Format::parseObject() for more.
513      *
514      * @param source    The string to be parsed into an object.
515      * @param result    Formattable to be set to the parse result.
516      *                  If parse fails, return contents are undefined.
517      * @param parse_pos The position to start parsing at. Upon return
518      *                  this param is set to the position after the
519      *                  last character successfully parsed. If the
520      *                  source is not parsed successfully, this param
521      *                  will remain unchanged.
522      * @stable ICU 2.0
523      */
524     virtual void parseObject(const UnicodeString& source,
525                              Formattable& result,
526                              ParsePosition& parse_pos) const override;
527 
528     /**
529      * Create a default date/time formatter that uses the SHORT style for both
530      * the date and the time.
531      *
532      * @return A date/time formatter which the caller owns.
533      * @stable ICU 2.0
534      */
535     static DateFormat* U_EXPORT2 createInstance(void);
536 
537     /**
538      * Creates a time formatter with the given formatting style for the given
539      * locale.
540      *
541      * @param style     The given formatting style. For example,
542      *                  SHORT for "h:mm a" in the US locale. Relative
543      *                  time styles are not currently supported.
544      * @param aLocale   The given locale.
545      * @return          A time formatter which the caller owns.
546      * @stable ICU 2.0
547      */
548     static DateFormat* U_EXPORT2 createTimeInstance(EStyle style = kDefault,
549                                           const Locale& aLocale = Locale::getDefault());
550 
551     /**
552      * Creates a date formatter with the given formatting style for the given
553      * const locale.
554      *
555      * @param style     The given formatting style. For example, SHORT for "M/d/yy" in the
556      *                  US locale. As currently implemented, relative date formatting only
557      *                  affects a limited range of calendar days before or after the
558      *                  current date, based on the CLDR &lt;field type="day"&gt;/&lt;relative&gt; data:
559      *                  For example, in English, "Yesterday", "Today", and "Tomorrow".
560      *                  Outside of this range, dates are formatted using the corresponding
561      *                  non-relative style.
562      * @param aLocale   The given locale.
563      * @return          A date formatter which the caller owns.
564      * @stable ICU 2.0
565      */
566     static DateFormat* U_EXPORT2 createDateInstance(EStyle style = kDefault,
567                                           const Locale& aLocale = Locale::getDefault());
568 
569     /**
570      * Creates a date/time formatter with the given formatting styles for the
571      * given locale.
572      *
573      * @param dateStyle The given formatting style for the date portion of the result.
574      *                  For example, SHORT for "M/d/yy" in the US locale. As currently
575      *                  implemented, relative date formatting only affects a limited range
576      *                  of calendar days before or after the current date, based on the
577      *                  CLDR &lt;field type="day"&gt;/&lt;relative&gt; data: For example, in English,
578      *                  "Yesterday", "Today", and "Tomorrow". Outside of this range, dates
579      *                  are formatted using the corresponding non-relative style.
580      * @param timeStyle The given formatting style for the time portion of the result.
581      *                  For example, SHORT for "h:mm a" in the US locale. Relative
582      *                  time styles are not currently supported.
583      * @param aLocale   The given locale.
584      * @return          A date/time formatter which the caller owns.
585      * @stable ICU 2.0
586      */
587     static DateFormat* U_EXPORT2 createDateTimeInstance(EStyle dateStyle = kDefault,
588                                               EStyle timeStyle = kDefault,
589                                               const Locale& aLocale = Locale::getDefault());
590 
591 #ifndef U_HIDE_INTERNAL_API
592     /**
593      * Returns the best pattern given a skeleton and locale.
594      * @param locale the locale
595      * @param skeleton the skeleton
596      * @param status ICU error returned here
597      * @return the best pattern.
598      * @internal For ICU use only.
599      */
600     static UnicodeString getBestPattern(
601             const Locale &locale,
602             const UnicodeString &skeleton,
603             UErrorCode &status);
604 #endif  /* U_HIDE_INTERNAL_API */
605 
606     /**
607      * Creates a date/time formatter for the given skeleton and
608      * default locale.
609      *
610      * @param skeleton The skeleton e.g "yMMMMd." Fields in the skeleton can
611      *                 be in any order, and this method uses the locale to
612      *                 map the skeleton to a pattern that includes locale
613      *                 specific separators with the fields in the appropriate
614      *                 order for that locale.
615      * @param status   Any error returned here.
616      * @return         A date/time formatter which the caller owns.
617      * @stable ICU 55
618      */
619     static DateFormat* U_EXPORT2 createInstanceForSkeleton(
620             const UnicodeString& skeleton,
621             UErrorCode &status);
622 
623     /**
624      * Creates a date/time formatter for the given skeleton and locale.
625      *
626      * @param skeleton The skeleton e.g "yMMMMd." Fields in the skeleton can
627      *                 be in any order, and this method uses the locale to
628      *                 map the skeleton to a pattern that includes locale
629      *                 specific separators with the fields in the appropriate
630      *                 order for that locale.
631      * @param locale  The given locale.
632      * @param status   Any error returned here.
633      * @return         A date/time formatter which the caller owns.
634      * @stable ICU 55
635      */
636     static DateFormat* U_EXPORT2 createInstanceForSkeleton(
637             const UnicodeString& skeleton,
638             const Locale &locale,
639             UErrorCode &status);
640 
641     /**
642      * Creates a date/time formatter for the given skeleton and locale.
643      *
644      * @param calendarToAdopt the calendar returned DateFormat is to use.
645      * @param skeleton The skeleton e.g "yMMMMd." Fields in the skeleton can
646      *                 be in any order, and this method uses the locale to
647      *                 map the skeleton to a pattern that includes locale
648      *                 specific separators with the fields in the appropriate
649      *                 order for that locale.
650      * @param locale  The given locale.
651      * @param status   Any error returned here.
652      * @return         A date/time formatter which the caller owns.
653      * @stable ICU 55
654      */
655     static DateFormat* U_EXPORT2 createInstanceForSkeleton(
656             Calendar *calendarToAdopt,
657             const UnicodeString& skeleton,
658             const Locale &locale,
659             UErrorCode &status);
660 
661 
662     /**
663      * Gets the set of locales for which DateFormats are installed.
664      * @param count Filled in with the number of locales in the list that is returned.
665      * @return the set of locales for which DateFormats are installed.  The caller
666      *  does NOT own this list and must not delete it.
667      * @stable ICU 2.0
668      */
669     static const Locale* U_EXPORT2 getAvailableLocales(int32_t& count);
670 
671     /**
672      * Returns whether both date/time parsing in the encapsulated Calendar object and DateFormat whitespace &
673      * numeric processing is lenient.
674      * @stable ICU 2.0
675      */
676     virtual UBool isLenient(void) const;
677 
678     /**
679      * Specifies whether date/time parsing is to be lenient.  With
680      * lenient parsing, the parser may use heuristics to interpret inputs that
681      * do not precisely match this object's format.  Without lenient parsing,
682      * inputs must match this object's format more closely.
683      *
684      * Note: ICU 53 introduced finer grained control of leniency (and added
685      * new control points) making the preferred method a combination of
686      * setCalendarLenient() & setBooleanAttribute() calls.
687      * This method supports prior functionality but may not support all
688      * future leniency control & behavior of DateFormat. For control of pre 53 leniency,
689      * Calendar and DateFormat whitespace & numeric tolerance, this method is safe to
690      * use. However, mixing leniency control via this method and modification of the
691      * newer attributes via setBooleanAttribute() may produce undesirable
692      * results.
693      *
694      * @param lenient  True specifies date/time interpretation to be lenient.
695      * @see Calendar::setLenient
696      * @stable ICU 2.0
697      */
698     virtual void setLenient(UBool lenient);
699 
700 
701     /**
702      * Returns whether date/time parsing in the encapsulated Calendar object processing is lenient.
703      * @stable ICU 53
704      */
705     virtual UBool isCalendarLenient(void) const;
706 
707 
708     /**
709      * Specifies whether encapsulated Calendar date/time parsing is to be lenient.  With
710      * lenient parsing, the parser may use heuristics to interpret inputs that
711      * do not precisely match this object's format.  Without lenient parsing,
712      * inputs must match this object's format more closely.
713      * @param lenient when true, parsing is lenient
714      * @see com.ibm.icu.util.Calendar#setLenient
715      * @stable ICU 53
716      */
717     virtual void setCalendarLenient(UBool lenient);
718 
719 
720     /**
721      * Gets the calendar associated with this date/time formatter.
722      * The calendar is owned by the formatter and must not be modified.
723      * Also, the calendar does not reflect the results of a parse operation.
724      * To parse to a calendar, use {@link #parse(const UnicodeString&, Calendar& cal, ParsePosition&) const parse(const UnicodeString&, Calendar& cal, ParsePosition&)}
725      * @return the calendar associated with this date/time formatter.
726      * @stable ICU 2.0
727      */
728     virtual const Calendar* getCalendar(void) const;
729 
730     /**
731      * Set the calendar to be used by this date format. Initially, the default
732      * calendar for the specified or default locale is used.  The caller should
733      * not delete the Calendar object after it is adopted by this call.
734      * Adopting a new calendar will change to the default symbols.
735      *
736      * @param calendarToAdopt    Calendar object to be adopted.
737      * @stable ICU 2.0
738      */
739     virtual void adoptCalendar(Calendar* calendarToAdopt);
740 
741     /**
742      * Set the calendar to be used by this date format. Initially, the default
743      * calendar for the specified or default locale is used.
744      *
745      * @param newCalendar Calendar object to be set.
746      * @stable ICU 2.0
747      */
748     virtual void setCalendar(const Calendar& newCalendar);
749 
750 
751     /**
752      * Gets the number formatter which this date/time formatter uses to format
753      * and parse the numeric portions of the pattern.
754      * @return the number formatter which this date/time formatter uses.
755      * @stable ICU 2.0
756      */
757     virtual const NumberFormat* getNumberFormat(void) const;
758 
759     /**
760      * Allows you to set the number formatter.  The caller should
761      * not delete the NumberFormat object after it is adopted by this call.
762      * @param formatToAdopt     NumberFormat object to be adopted.
763      * @stable ICU 2.0
764      */
765     virtual void adoptNumberFormat(NumberFormat* formatToAdopt);
766 
767     /**
768      * Allows you to set the number formatter.
769      * @param newNumberFormat  NumberFormat object to be set.
770      * @stable ICU 2.0
771      */
772     virtual void setNumberFormat(const NumberFormat& newNumberFormat);
773 
774     /**
775      * Returns a reference to the TimeZone used by this DateFormat's calendar.
776      * @return the time zone associated with the calendar of DateFormat.
777      * @stable ICU 2.0
778      */
779     virtual const TimeZone& getTimeZone(void) const;
780 
781     /**
782      * Sets the time zone for the calendar of this DateFormat object. The caller
783      * no longer owns the TimeZone object and should not delete it after this call.
784      * @param zoneToAdopt the TimeZone to be adopted.
785      * @stable ICU 2.0
786      */
787     virtual void adoptTimeZone(TimeZone* zoneToAdopt);
788 
789     /**
790      * Sets the time zone for the calendar of this DateFormat object.
791      * @param zone the new time zone.
792      * @stable ICU 2.0
793      */
794     virtual void setTimeZone(const TimeZone& zone);
795 
796     /**
797      * Set a particular UDisplayContext value in the formatter, such as
798      * UDISPCTX_CAPITALIZATION_FOR_STANDALONE.
799      * @param value The UDisplayContext value to set.
800      * @param status Input/output status. If at entry this indicates a failure
801      *               status, the function will do nothing; otherwise this will be
802      *               updated with any new status from the function.
803      * @stable ICU 53
804      */
805     virtual void setContext(UDisplayContext value, UErrorCode& status);
806 
807     /**
808      * Get the formatter's UDisplayContext value for the specified UDisplayContextType,
809      * such as UDISPCTX_TYPE_CAPITALIZATION.
810      * @param type The UDisplayContextType whose value to return
811      * @param status Input/output status. If at entry this indicates a failure
812      *               status, the function will do nothing; otherwise this will be
813      *               updated with any new status from the function.
814      * @return The UDisplayContextValue for the specified type.
815      * @stable ICU 53
816      */
817     virtual UDisplayContext getContext(UDisplayContextType type, UErrorCode& status) const;
818 
819    /**
820      * Sets an boolean attribute on this DateFormat.
821      * May return U_UNSUPPORTED_ERROR if this instance does not support
822      * the specified attribute.
823      * @param attr the attribute to set
824      * @param newvalue new value
825      * @param status the error type
826      * @return *this - for chaining (example: format.setAttribute(...).setAttribute(...) )
827      * @stable ICU 53
828      */
829 
830     virtual DateFormat&  U_EXPORT2 setBooleanAttribute(UDateFormatBooleanAttribute attr,
831     									UBool newvalue,
832     									UErrorCode &status);
833 
834     /**
835      * Returns a boolean from this DateFormat
836      * May return U_UNSUPPORTED_ERROR if this instance does not support
837      * the specified attribute.
838      * @param attr the attribute to set
839      * @param status the error type
840      * @return the attribute value. Undefined if there is an error.
841      * @stable ICU 53
842      */
843     virtual UBool U_EXPORT2 getBooleanAttribute(UDateFormatBooleanAttribute attr, UErrorCode &status) const;
844 
845 protected:
846     /**
847      * Default constructor.  Creates a DateFormat with no Calendar or NumberFormat
848      * associated with it.  This constructor depends on the subclasses to fill in
849      * the calendar and numberFormat fields.
850      * @stable ICU 2.0
851      */
852     DateFormat();
853 
854     /**
855      * Copy constructor.
856      * @stable ICU 2.0
857      */
858     DateFormat(const DateFormat&);
859 
860     /**
861      * Default assignment operator.
862      * @stable ICU 2.0
863      */
864     DateFormat& operator=(const DateFormat&);
865 
866     /**
867      * The calendar that DateFormat uses to produce the time field values needed
868      * to implement date/time formatting. Subclasses should generally initialize
869      * this to the default calendar for the locale associated with this DateFormat.
870      * @stable ICU 2.4
871      */
872     Calendar* fCalendar;
873 
874     /**
875      * The number formatter that DateFormat uses to format numbers in dates and
876      * times. Subclasses should generally initialize this to the default number
877      * format for the locale associated with this DateFormat.
878      * @stable ICU 2.4
879      */
880     NumberFormat* fNumberFormat;
881 
882 
883 private:
884 
885     /**
886      * Gets the date/time formatter with the given formatting styles for the
887      * given locale.
888      * @param dateStyle the given date formatting style.
889      * @param timeStyle the given time formatting style.
890      * @param inLocale the given locale.
891      * @return a date/time formatter, or 0 on failure.
892      */
893     static DateFormat* U_EXPORT2 create(EStyle timeStyle, EStyle dateStyle, const Locale& inLocale);
894 
895 
896     /**
897      * enum set of active boolean attributes for this instance
898      */
899     EnumSet<UDateFormatBooleanAttribute, 0, UDAT_BOOLEAN_ATTRIBUTE_COUNT> fBoolFlags;
900 
901 
902     UDisplayContext fCapitalizationContext;
903     friend class DateFmtKeyByStyle;
904 
905 public:
906 #ifndef U_HIDE_OBSOLETE_API
907     /**
908      * Field selector for FieldPosition for DateFormat fields.
909      * @obsolete ICU 3.4 use UDateFormatField instead, since this API will be
910      * removed in that release
911      */
912     enum EField
913     {
914         // Obsolete; use UDateFormatField instead
915         kEraField = UDAT_ERA_FIELD,
916         kYearField = UDAT_YEAR_FIELD,
917         kMonthField = UDAT_MONTH_FIELD,
918         kDateField = UDAT_DATE_FIELD,
919         kHourOfDay1Field = UDAT_HOUR_OF_DAY1_FIELD,
920         kHourOfDay0Field = UDAT_HOUR_OF_DAY0_FIELD,
921         kMinuteField = UDAT_MINUTE_FIELD,
922         kSecondField = UDAT_SECOND_FIELD,
923         kMillisecondField = UDAT_FRACTIONAL_SECOND_FIELD,
924         kDayOfWeekField = UDAT_DAY_OF_WEEK_FIELD,
925         kDayOfYearField = UDAT_DAY_OF_YEAR_FIELD,
926         kDayOfWeekInMonthField = UDAT_DAY_OF_WEEK_IN_MONTH_FIELD,
927         kWeekOfYearField = UDAT_WEEK_OF_YEAR_FIELD,
928         kWeekOfMonthField = UDAT_WEEK_OF_MONTH_FIELD,
929         kAmPmField = UDAT_AM_PM_FIELD,
930         kHour1Field = UDAT_HOUR1_FIELD,
931         kHour0Field = UDAT_HOUR0_FIELD,
932         kTimezoneField = UDAT_TIMEZONE_FIELD,
933         kYearWOYField = UDAT_YEAR_WOY_FIELD,
934         kDOWLocalField = UDAT_DOW_LOCAL_FIELD,
935         kExtendedYearField = UDAT_EXTENDED_YEAR_FIELD,
936         kJulianDayField = UDAT_JULIAN_DAY_FIELD,
937         kMillisecondsInDayField = UDAT_MILLISECONDS_IN_DAY_FIELD,
938 
939         // Obsolete; use UDateFormatField instead
940         ERA_FIELD = UDAT_ERA_FIELD,
941         YEAR_FIELD = UDAT_YEAR_FIELD,
942         MONTH_FIELD = UDAT_MONTH_FIELD,
943         DATE_FIELD = UDAT_DATE_FIELD,
944         HOUR_OF_DAY1_FIELD = UDAT_HOUR_OF_DAY1_FIELD,
945         HOUR_OF_DAY0_FIELD = UDAT_HOUR_OF_DAY0_FIELD,
946         MINUTE_FIELD = UDAT_MINUTE_FIELD,
947         SECOND_FIELD = UDAT_SECOND_FIELD,
948         MILLISECOND_FIELD = UDAT_FRACTIONAL_SECOND_FIELD,
949         DAY_OF_WEEK_FIELD = UDAT_DAY_OF_WEEK_FIELD,
950         DAY_OF_YEAR_FIELD = UDAT_DAY_OF_YEAR_FIELD,
951         DAY_OF_WEEK_IN_MONTH_FIELD = UDAT_DAY_OF_WEEK_IN_MONTH_FIELD,
952         WEEK_OF_YEAR_FIELD = UDAT_WEEK_OF_YEAR_FIELD,
953         WEEK_OF_MONTH_FIELD = UDAT_WEEK_OF_MONTH_FIELD,
954         AM_PM_FIELD = UDAT_AM_PM_FIELD,
955         HOUR1_FIELD = UDAT_HOUR1_FIELD,
956         HOUR0_FIELD = UDAT_HOUR0_FIELD,
957         TIMEZONE_FIELD = UDAT_TIMEZONE_FIELD
958     };
959 #endif  /* U_HIDE_OBSOLETE_API */
960 };
961 
962 U_NAMESPACE_END
963 
964 #endif /* #if !UCONFIG_NO_FORMATTING */
965 
966 #endif /* U_SHOW_CPLUSPLUS_API */
967 
968 #endif // _DATEFMT
969 //eof
970