icuSources/i18n/unicode/datefmt.h

   1 /*
   2  ********************************************************************************
   3  *   Copyright (C) 1997-2012, International Business Machines
   4  *   Corporation and others.  All Rights Reserved.
   5  ********************************************************************************
   6  *
   7  * File DATEFMT.H
   8  *
   9  * Modification History:
  10  *
  11  *   Date        Name        Description
  12  *   02/19/97    aliu        Converted from java.
  13  *   04/01/97    aliu        Added support for centuries.
  14  *   07/23/98    stephen     JDK 1.2 sync
  15  *   11/15/99    weiv        Added support for week of year/day of week formatting
  16  ********************************************************************************
  17  */
  18
  19 #ifndef DATEFMT_H
  20 #define DATEFMT_H
  21
  22 #include "unicode/utypes.h"
  23
  24 #if !UCONFIG_NO_FORMATTING
  25
  26 #include "unicode/udat.h"
  27 #include "unicode/calendar.h"
  28 #include "unicode/numfmt.h"
  29 #include "unicode/format.h"
  30 #include "unicode/locid.h"
  31
  32 /**
  33  * \file
  34  * \brief C++ API: Abstract class for converting dates.
  35  */
  36
  37 U_NAMESPACE_BEGIN
  38
  39 class TimeZone;
  40 class DateTimePatternGenerator;
  41
  42 /**
  43  * DateFormat is an abstract class for a family of classes that convert dates and
  44  * times from their internal representations to textual form and back again in a
  45  * language-independent manner. Converting from the internal representation (milliseconds
  46  * since midnight, January 1, 1970) to text is known as "formatting," and converting
  47  * from text to millis is known as "parsing."  We currently define only one concrete
  48  * subclass of DateFormat: SimpleDateFormat, which can handle pretty much all normal
  49  * date formatting and parsing actions.
  50  * <P>
  51  * DateFormat helps you to format and parse dates for any locale. Your code can
  52  * be completely independent of the locale conventions for months, days of the
  53  * week, or even the calendar format: lunar vs. solar.
  54  * <P>
  55  * To format a date for the current Locale, use one of the static factory
  56  * methods:
  57  * <pre>
  58  * \code
  59  *      DateFormat* dfmt = DateFormat::createDateInstance();
  60  *      UDate myDate = Calendar::getNow();
  61  *      UnicodeString myString;
  62  *      myString = dfmt->format( myDate, myString );
  63  * \endcode
  64  * </pre>
  65  * If you are formatting multiple numbers, it is more efficient to get the
  66  * format and use it multiple times so that the system doesn't have to fetch the
  67  * information about the local language and country conventions multiple times.
  68  * <pre>
  69  * \code
  70  *      DateFormat* df = DateFormat::createDateInstance();
  71  *      UnicodeString myString;
  72  *      UDate myDateArr[] = { 0.0, 100000000.0, 2000000000.0 }; // test values
  73  *      for (int32_t i = 0; i < 3; ++i) {
  74  *          myString.remove();
  75  *          cout << df->format( myDateArr[i], myString ) << endl;
  76  *      }
  77  * \endcode
  78  * </pre>
  79  * To get specific fields of a date, you can use UFieldPosition to
  80  * get specific fields.
  81  * <pre>
  82  * \code
  83  *      DateFormat* dfmt = DateFormat::createDateInstance();
  84  *      FieldPosition pos(DateFormat::YEAR_FIELD);
  85  *      UnicodeString myString;
  86  *      myString = dfmt->format( myDate, myString );
  87  *      cout << myString << endl;
  88  *      cout << pos.getBeginIndex() << "," << pos. getEndIndex() << endl;
  89  * \endcode
  90  * </pre>
  91  * To format a date for a different Locale, specify it in the call to
  92  * createDateInstance().
  93  * <pre>
  94  * \code
  95  *       DateFormat* df =
  96  *           DateFormat::createDateInstance( DateFormat::SHORT, Locale::getFrance());
  97  * \endcode
  98  * </pre>
  99  * You can use a DateFormat to parse also.
 100  * <pre>
 101  * \code
 102  *       UErrorCode status = U_ZERO_ERROR;
 103  *       UDate myDate = df->parse(myString, status);
 104  * \endcode
 105  * </pre>
 106  * Use createDateInstance() to produce the normal date format for that country.
 107  * There are other static factory methods available. Use createTimeInstance()
 108  * to produce the normal time format for that country. Use createDateTimeInstance()
 109  * to produce a DateFormat that formats both date and time. You can pass in
 110  * different options to these factory methods to control the length of the
 111  * result; from SHORT to MEDIUM to LONG to FULL. The exact result depends on the
 112  * locale, but generally:
 113  * <ul type=round>
 114  *   <li>   SHORT is completely numeric, such as 12/13/52 or 3:30pm
 115  *   <li>   MEDIUM is longer, such as Jan 12, 1952
 116  *   <li>   LONG is longer, such as January 12, 1952 or 3:30:32pm
 117  *   <li>   FULL is pretty completely specified, such as
 118  *          Tuesday, April 12, 1952 AD or 3:30:42pm PST.
 119  * </ul>
 120  * You can also set the time zone on the format if you wish. If you want even
 121  * more control over the format or parsing, (or want to give your users more
 122  * control), you can try casting the DateFormat you get from the factory methods
 123  * to a SimpleDateFormat. This will work for the majority of countries; just
 124  * remember to chck getDynamicClassID() before carrying out the cast.
 125  * <P>
 126  * You can also use forms of the parse and format methods with ParsePosition and
 127  * FieldPosition to allow you to
 128  * <ul type=round>
 129  *   <li>   Progressively parse through pieces of a string.
 130  *   <li>   Align any particular field, or find out where it is for selection
 131  *          on the screen.
 132  * </ul>
 133  *
 134  * <p><em>User subclasses are not supported.</em> While clients may write
 135  * subclasses, such code will not necessarily work and will not be
 136  * guaranteed to work stably from release to release.
 137  */
 138 class U_I18N_API DateFormat : public Format {
 139 public:
 140
 141     /**
 142      * Constants for various style patterns. These reflect the order of items in
 143      * the DateTimePatterns resource. There are 4 time patterns, 4 date patterns,
 144      * the default date-time pattern, and 4 date-time patterns. Each block of 4 values
 145      * in the resource occurs in the order full, long, medium, short.
 146      * @stable ICU 2.4
 147      */
 148     enum EStyle
 149     {
 150         kNone   = -1,
 151
 152         kFull   = 0,
 153         kLong   = 1,
 154         kMedium = 2,
 155         kShort  = 3,
 156
 157         kDateOffset   = kShort + 1,
 158      // kFull   + kDateOffset = 4
 159      // kLong   + kDateOffset = 5
 160      // kMedium + kDateOffset = 6
 161      // kShort  + kDateOffset = 7
 162
 163         kDateTime             = 8,
 164      // Default DateTime
 165
 166         kDateTimeOffset = kDateTime + 1,
 167      // kFull   + kDateTimeOffset = 9
 168      // kLong   + kDateTimeOffset = 10
 169      // kMedium + kDateTimeOffset = 11
 170      // kShort  + kDateTimeOffset = 12
 171
 172         // relative dates
 173         kRelative = (1 << 7),
 174
 175         kFullRelative = (kFull | kRelative),
 176
 177         kLongRelative = kLong | kRelative,
 178
 179         kMediumRelative = kMedium | kRelative,
 180
 181         kShortRelative = kShort | kRelative,
 182
 183
 184         kDefault      = kMedium,
 185
 186
 187
 188     /**
 189      * These constants are provided for backwards compatibility only.
 190      * Please use the C++ style constants defined above.
 191      */
 192         FULL        = kFull,
 193         LONG        = kLong,
 194         MEDIUM        = kMedium,
 195         SHORT        = kShort,
 196         DEFAULT        = kDefault,
 197         DATE_OFFSET    = kDateOffset,
 198         NONE        = kNone,
 199         DATE_TIME    = kDateTime
 200     };
 201
 202     /**
 203      * Destructor.
 204      * @stable ICU 2.0
 205      */
 206     virtual ~DateFormat();
 207
 208     /**
 209      * Equality operator.  Returns true if the two formats have the same behavior.
 210      * @stable ICU 2.0
 211      */
 212     virtual UBool operator==(const Format&) const;
 213
 214
 215     using Format::format;
 216
 217     /**
 218      * Format an object to produce a string. This method handles Formattable
 219      * objects with a UDate type. If a the Formattable object type is not a Date,
 220      * then it returns a failing UErrorCode.
 221      *
 222      * @param obj       The object to format. Must be a Date.
 223      * @param appendTo  Output parameter to receive result.
 224      *                  Result is appended to existing contents.
 225      * @param pos       On input: an alignment field, if desired.
 226      *                  On output: the offsets of the alignment field.
 227      * @param status    Output param filled with success/failure status.
 228      * @return          Reference to 'appendTo' parameter.
 229      * @stable ICU 2.0
 230      */
 231     virtual UnicodeString& format(const Formattable& obj,
 232                                   UnicodeString& appendTo,
 233                                   FieldPosition& pos,
 234                                   UErrorCode& status) const;
 235
 236     /**
 237      * Format an object to produce a string. This method handles Formattable
 238      * objects with a UDate type. If a the Formattable object type is not a Date,
 239      * then it returns a failing UErrorCode.
 240      *
 241      * @param obj       The object to format. Must be a Date.
 242      * @param appendTo  Output parameter to receive result.
 243      *                  Result is appended to existing contents.
 244      * @param posIter   On return, can be used to iterate over positions
 245      *                  of fields generated by this format call.  Field values
 246      *                  are defined in UDateFormatField.  Can be NULL.
 247      * @param status    Output param filled with success/failure status.
 248      * @return          Reference to 'appendTo' parameter.
 249      * @stable ICU 4.4
 250      */
 251     virtual UnicodeString& format(const Formattable& obj,
 252                                   UnicodeString& appendTo,
 253                                   FieldPositionIterator* posIter,
 254                                   UErrorCode& status) const;
 255     /**
 256      * Formats a date into a date/time string. This is an abstract method which
 257      * concrete subclasses must implement.
 258      * <P>
 259      * On input, the FieldPosition parameter may have its "field" member filled with
 260      * an enum value specifying a field.  On output, the FieldPosition will be filled
 261      * in with the text offsets for that field.
 262      * <P> For example, given a time text
 263      * "1996.07.10 AD at 15:08:56 PDT", if the given fieldPosition.field is
 264      * UDAT_YEAR_FIELD, the offsets fieldPosition.beginIndex and
 265      * statfieldPositionus.getEndIndex will be set to 0 and 4, respectively.
 266      * <P> Notice
 267      * that if the same time field appears more than once in a pattern, the status will
 268      * be set for the first occurence of that time field. For instance,
 269      * formatting a UDate to the time string "1 PM PDT (Pacific Daylight Time)"
 270      * using the pattern "h a z (zzzz)" and the alignment field
 271      * DateFormat::TIMEZONE_FIELD, the offsets fieldPosition.beginIndex and
 272      * fieldPosition.getEndIndex will be set to 5 and 8, respectively, for the first
 273      * occurence of the timezone pattern character 'z'.
 274      *
 275      * @param cal           Calendar set to the date and time to be formatted
 276      *                      into a date/time string.  When the calendar type is
 277      *                      different from the internal calendar held by this
 278      *                      DateFormat instance, the date and the time zone will
 279      *                      be inherited from the input calendar, but other calendar
 280      *                      field values will be calculated by the internal calendar.
 281      * @param appendTo      Output parameter to receive result.
 282      *                      Result is appended to existing contents.
 283      * @param fieldPosition On input: an alignment field, if desired (see examples above)
 284      *                      On output: the offsets of the alignment field (see examples above)
 285      * @return              Reference to 'appendTo' parameter.
 286      * @stable ICU 2.1
 287      */
 288     virtual UnicodeString& format(  Calendar& cal,
 289                                     UnicodeString& appendTo,
 290                                     FieldPosition& fieldPosition) const = 0;
 291
 292     /**
 293      * Formats a date into a date/time string. Subclasses should implement this method.
 294      *
 295      * @param cal       Calendar set to the date and time to be formatted
 296      *                  into a date/time string.  When the calendar type is
 297      *                  different from the internal calendar held by this
 298      *                  DateFormat instance, the date and the time zone will
 299      *                  be inherited from the input calendar, but other calendar
 300      *                  field values will be calculated by the internal calendar.
 301      * @param appendTo  Output parameter to receive result.
 302      *                  Result is appended to existing contents.
 303      * @param posIter   On return, can be used to iterate over positions
 304      *                  of fields generated by this format call.  Field values
 305      *                  are defined in UDateFormatField.  Can be NULL.
 306      * @param status    error status.
 307      * @return          Reference to 'appendTo' parameter.
 308      * @stable ICU 4.4
 309      */
 310     virtual UnicodeString& format(Calendar& cal,
 311                                   UnicodeString& appendTo,
 312                                   FieldPositionIterator* posIter,
 313                                   UErrorCode& status) const;
 314     /**
 315      * Formats a UDate into a date/time string.
 316      * <P>
 317      * On input, the FieldPosition parameter may have its "field" member filled with
 318      * an enum value specifying a field.  On output, the FieldPosition will be filled
 319      * in with the text offsets for that field.
 320      * <P> For example, given a time text
 321      * "1996.07.10 AD at 15:08:56 PDT", if the given fieldPosition.field is
 322      * UDAT_YEAR_FIELD, the offsets fieldPosition.beginIndex and
 323      * statfieldPositionus.getEndIndex will be set to 0 and 4, respectively.
 324      * <P> Notice
 325      * that if the same time field appears more than once in a pattern, the status will
 326      * be set for the first occurence of that time field. For instance,
 327      * formatting a UDate to the time string "1 PM PDT (Pacific Daylight Time)"
 328      * using the pattern "h a z (zzzz)" and the alignment field
 329      * DateFormat::TIMEZONE_FIELD, the offsets fieldPosition.beginIndex and
 330      * fieldPosition.getEndIndex will be set to 5 and 8, respectively, for the first
 331      * occurence of the timezone pattern character 'z'.
 332      *
 333      * @param date          UDate to be formatted into a date/time string.
 334      * @param appendTo      Output parameter to receive result.
 335      *                      Result is appended to existing contents.
 336      * @param fieldPosition On input: an alignment field, if desired (see examples above)
 337      *                      On output: the offsets of the alignment field (see examples above)
 338      * @return              Reference to 'appendTo' parameter.
 339      * @stable ICU 2.0
 340      */
 341     UnicodeString& format(  UDate date,
 342                             UnicodeString& appendTo,
 343                             FieldPosition& fieldPosition) const;
 344
 345     /**
 346      * Formats a UDate into a date/time string.
 347      *
 348      * @param date      UDate to be formatted into a date/time string.
 349      * @param appendTo  Output parameter to receive result.
 350      *                  Result is appended to existing contents.
 351      * @param posIter   On return, can be used to iterate over positions
 352      *                  of fields generated by this format call.  Field values
 353      *                  are defined in UDateFormatField.  Can be NULL.
 354      * @param status    error status.
 355      * @return          Reference to 'appendTo' parameter.
 356      * @stable ICU 4.4
 357      */
 358     UnicodeString& format(UDate date,
 359                           UnicodeString& appendTo,
 360                           FieldPositionIterator* posIter,
 361                           UErrorCode& status) const;
 362     /**
 363      * Formats a UDate into a date/time string. If there is a problem, you won't
 364      * know, using this method. Use the overloaded format() method which takes a
 365      * FieldPosition& to detect formatting problems.
 366      *
 367      * @param date      The UDate value to be formatted into a string.
 368      * @param appendTo  Output parameter to receive result.
 369      *                  Result is appended to existing contents.
 370      * @return          Reference to 'appendTo' parameter.
 371      * @stable ICU 2.0
 372      */
 373     UnicodeString& format(UDate date, UnicodeString& appendTo) const;
 374
 375     /**
 376      * Redeclared Format method.
 377      *
 378      * @param obj       The object to be formatted into a string.
 379      * @param appendTo  Output parameter to receive result.
 380      *                  Result is appended to existing contents.
 381      * @param status    Output param filled with success/failure status.
 382      * @return          Reference to 'appendTo' parameter.
 383      * @stable ICU 2.0
 384      */
 385     UnicodeString& format(const Formattable& obj,
 386                           UnicodeString& appendTo,
 387                           UErrorCode& status) const;
 388
 389     /**
 390      * Parse a date/time string. For example, a time text "07/10/96 4:5 PM, PDT"
 391      * will be parsed into a UDate that is equivalent to Date(837039928046).
 392      * Parsing begins at the beginning of the string and proceeds as far as
 393      * possible.  Assuming no parse errors were encountered, this function
 394      * doesn't return any information about how much of the string was consumed
 395      * by the parsing.  If you need that information, use the version of
 396      * parse() that takes a ParsePosition.
 397      * <P>
 398      * By default, parsing is lenient: If the input is not in the form used by
 399      * this object's format method but can still be parsed as a date, then the
 400      * parse succeeds. Clients may insist on strict adherence to the format by
 401      * calling setLenient(false).
 402      * @see DateFormat::setLenient(boolean)
 403      * <P>
 404      * Note that the normal date formats associated with some calendars - such
 405      * as the Chinese lunar calendar - do not specify enough fields to enable
 406      * dates to be parsed unambiguously. In the case of the Chinese lunar
 407      * calendar, while the year within the current 60-year cycle is specified,
 408      * the number of such cycles since the start date of the calendar (in the
 409      * ERA field of the Calendar object) is not normally part of the format,
 410      * and parsing may assume the wrong era. For cases such as this it is
 411      * recommended that clients parse using the method
 412      * parse(const UnicodeString&, Calendar& cal, ParsePosition&)
 413      * with the Calendar passed in set to the current date, or to a date
 414      * within the era/cycle that should be assumed if absent in the format.
 415      *
 416      * @param text      The date/time string to be parsed into a UDate value.
 417      * @param status    Output param to be set to success/failure code. If
 418      *                  'text' cannot be parsed, it will be set to a failure
 419      *                  code.
 420      * @return          The parsed UDate value, if successful.
 421      * @stable ICU 2.0
 422      */
 423     virtual UDate parse( const UnicodeString& text,
 424                         UErrorCode& status) const;
 425
 426     /**
 427      * Parse a date/time string beginning at the given parse position. For
 428      * example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
 429      * that is equivalent to Date(837039928046).
 430      * <P>
 431      * By default, parsing is lenient: If the input is not in the form used by
 432      * this object's format method but can still be parsed as a date, then the
 433      * parse succeeds. Clients may insist on strict adherence to the format by
 434      * calling setLenient(false).
 435      * @see DateFormat::setLenient(boolean)
 436      *
 437      * @param text  The date/time string to be parsed.
 438      * @param cal   A Calendar set on input to the date and time to be used for
 439      *              missing values in the date/time string being parsed, and set
 440      *              on output to the parsed date/time. When the calendar type is
 441      *              different from the internal calendar held by this DateFormat
 442      *              instance, the internal calendar will be cloned to a work
 443      *              calendar set to the same milliseconds and time zone as the
 444      *              cal parameter, field values will be parsed based on the work
 445      *              calendar, then the result (milliseconds and time zone) will
 446      *              be set in this calendar.
 447      * @param pos   On input, the position at which to start parsing; on
 448      *              output, the position at which parsing terminated, or the
 449      *              start position if the parse failed.
 450      * @stable ICU 2.1
 451      */
 452     virtual void parse( const UnicodeString& text,
 453                         Calendar& cal,
 454                         ParsePosition& pos) const = 0;
 455
 456     /**
 457      * Parse a date/time string beginning at the given parse position. For
 458      * example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
 459      * that is equivalent to Date(837039928046).
 460      * <P>
 461      * By default, parsing is lenient: If the input is not in the form used by
 462      * this object's format method but can still be parsed as a date, then the
 463      * parse succeeds. Clients may insist on strict adherence to the format by
 464      * calling setLenient(false).
 465      * @see DateFormat::setLenient(boolean)
 466      * <P>
 467      * Note that the normal date formats associated with some calendars - such
 468      * as the Chinese lunar calendar - do not specify enough fields to enable
 469      * dates to be parsed unambiguously. In the case of the Chinese lunar
 470      * calendar, while the year within the current 60-year cycle is specified,
 471      * the number of such cycles since the start date of the calendar (in the
 472      * ERA field of the Calendar object) is not normally part of the format,
 473      * and parsing may assume the wrong era. For cases such as this it is
 474      * recommended that clients parse using the method
 475      * parse(const UnicodeString&, Calendar& cal, ParsePosition&)
 476      * with the Calendar passed in set to the current date, or to a date
 477      * within the era/cycle that should be assumed if absent in the format.
 478      *
 479      * @param text  The date/time string to be parsed into a UDate value.
 480      * @param pos   On input, the position at which to start parsing; on
 481      *              output, the position at which parsing terminated, or the
 482      *              start position if the parse failed.
 483      * @return      A valid UDate if the input could be parsed.
 484      * @stable ICU 2.0
 485      */
 486     UDate parse( const UnicodeString& text,
 487                  ParsePosition& pos) const;
 488
 489     /**
 490      * Parse a string to produce an object. This methods handles parsing of
 491      * date/time strings into Formattable objects with UDate types.
 492      * <P>
 493      * Before calling, set parse_pos.index to the offset you want to start
 494      * parsing at in the source. After calling, parse_pos.index is the end of
 495      * the text you parsed. If error occurs, index is unchanged.
 496      * <P>
 497      * When parsing, leading whitespace is discarded (with a successful parse),
 498      * while trailing whitespace is left as is.
 499      * <P>
 500      * See Format::parseObject() for more.
 501      *
 502      * @param source    The string to be parsed into an object.
 503      * @param result    Formattable to be set to the parse result.
 504      *                  If parse fails, return contents are undefined.
 505      * @param parse_pos The position to start parsing at. Upon return
 506      *                  this param is set to the position after the
 507      *                  last character successfully parsed. If the
 508      *                  source is not parsed successfully, this param
 509      *                  will remain unchanged.
 510      * @return          A newly created Formattable* object, or NULL
 511      *                  on failure.  The caller owns this and should
 512      *                  delete it when done.
 513      * @stable ICU 2.0
 514      */
 515     virtual void parseObject(const UnicodeString& source,
 516                              Formattable& result,
 517                              ParsePosition& parse_pos) const;
 518
 519     /**
 520      * Create a default date/time formatter that uses the SHORT style for both
 521      * the date and the time.
 522      *
 523      * @return A date/time formatter which the caller owns.
 524      * @stable ICU 2.0
 525      */
 526     static DateFormat* U_EXPORT2 createInstance(void);
 527
 528     /**
 529      * Creates a time formatter with the given formatting style for the given
 530      * locale.
 531      *
 532      * @param style     The given formatting style. For example,
 533      *                  SHORT for "h:mm a" in the US locale. Relative
 534      *                  time styles are not currently supported.
 535      * @param aLocale   The given locale.
 536      * @return          A time formatter which the caller owns.
 537      * @stable ICU 2.0
 538      */
 539     static DateFormat* U_EXPORT2 createTimeInstance(EStyle style = kDefault,
 540                                           const Locale& aLocale = Locale::getDefault());
 541
 542     /**
 543      * Creates a date formatter with the given formatting style for the given
 544      * const locale.
 545      *
 546      * @param style     The given formatting style. For example, SHORT for "M/d/yy" in the
 547      *                  US locale. As currently implemented, relative date formatting only
 548      *                  affects a limited range of calendar days before or after the
 549      *                  current date, based on the CLDR &lt;field type="day"&gt;/&lt;relative&gt; data:
 550      *                  For example, in English, "Yesterday", "Today", and "Tomorrow".
 551      *                  Outside of this range, dates are formatted using the corresponding
 552      *                  non-relative style.
 553      * @param aLocale   The given locale.
 554      * @return          A date formatter which the caller owns.
 555      * @stable ICU 2.0
 556      */
 557     static DateFormat* U_EXPORT2 createDateInstance(EStyle style = kDefault,
 558                                           const Locale& aLocale = Locale::getDefault());
 559
 560     /**
 561      * Creates a date/time formatter with the given formatting styles for the
 562      * given locale.
 563      *
 564      * @param dateStyle The given formatting style for the date portion of the result.
 565      *                  For example, SHORT for "M/d/yy" in the US locale. As currently
 566      *                  implemented, relative date formatting only affects a limited range
 567      *                  of calendar days before or after the current date, based on the
 568      *                  CLDR &lt;field type="day"&gt;/&lt;relative&gt; data: For example, in English,
 569      *                  "Yesterday", "Today", and "Tomorrow". Outside of this range, dates
 570      *                  are formatted using the corresponding non-relative style.
 571      * @param timeStyle The given formatting style for the time portion of the result.
 572      *                  For example, SHORT for "h:mm a" in the US locale. Relative
 573      *                  time styles are not currently supported.
 574      * @param aLocale   The given locale.
 575      * @return          A date/time formatter which the caller owns.
 576      * @stable ICU 2.0
 577      */
 578     static DateFormat* U_EXPORT2 createDateTimeInstance(EStyle dateStyle = kDefault,
 579                                               EStyle timeStyle = kDefault,
 580                                               const Locale& aLocale = Locale::getDefault());
 581
 582     /**
 583      * Gets the set of locales for which DateFormats are installed.
 584      * @param count Filled in with the number of locales in the list that is returned.
 585      * @return the set of locales for which DateFormats are installed.  The caller
 586      *  does NOT own this list and must not delete it.
 587      * @stable ICU 2.0
 588      */
 589     static const Locale* U_EXPORT2 getAvailableLocales(int32_t& count);
 590
 591     /**
 592      * Returns true if the formatter is set for lenient parsing.
 593      * @stable ICU 2.0
 594      */
 595     virtual UBool isLenient(void) const;
 596
 597     /**
 598      * Specify whether or not date/time parsing is to be lenient. With lenient
 599      * parsing, the parser may use heuristics to interpret inputs that do not
 600      * precisely match this object's format. With strict parsing, inputs must
 601      * match this object's format.
 602      *
 603      * @param lenient  True specifies date/time interpretation to be lenient.
 604      * @see Calendar::setLenient
 605      * @stable ICU 2.0
 606      */
 607     virtual void setLenient(UBool lenient);
 608
 609     /**
 610      * Gets the calendar associated with this date/time formatter.
 611      * @return the calendar associated with this date/time formatter.
 612      * @stable ICU 2.0
 613      */
 614     virtual const Calendar* getCalendar(void) const;
 615
 616     /**
 617      * Set the calendar to be used by this date format. Initially, the default
 618      * calendar for the specified or default locale is used.  The caller should
 619      * not delete the Calendar object after it is adopted by this call.
 620      * Adopting a new calendar will change to the default symbols.
 621      *
 622      * @param calendarToAdopt    Calendar object to be adopted.
 623      * @stable ICU 2.0
 624      */
 625     virtual void adoptCalendar(Calendar* calendarToAdopt);
 626
 627     /**
 628      * Set the calendar to be used by this date format. Initially, the default
 629      * calendar for the specified or default locale is used.
 630      *
 631      * @param newCalendar Calendar object to be set.
 632      * @stable ICU 2.0
 633      */
 634     virtual void setCalendar(const Calendar& newCalendar);
 635
 636
 637     /**
 638      * Gets the number formatter which this date/time formatter uses to format
 639      * and parse the numeric portions of the pattern.
 640      * @return the number formatter which this date/time formatter uses.
 641      * @stable ICU 2.0
 642      */
 643     virtual const NumberFormat* getNumberFormat(void) const;
 644
 645     /**
 646      * Allows you to set the number formatter.  The caller should
 647      * not delete the NumberFormat object after it is adopted by this call.
 648      * @param formatToAdopt     NumberFormat object to be adopted.
 649      * @stable ICU 2.0
 650      */
 651     virtual void adoptNumberFormat(NumberFormat* formatToAdopt);
 652
 653     /**
 654      * Allows you to set the number formatter.
 655      * @param newNumberFormat  NumberFormat object to be set.
 656      * @stable ICU 2.0
 657      */
 658     virtual void setNumberFormat(const NumberFormat& newNumberFormat);
 659
 660     /**
 661      * Returns a reference to the TimeZone used by this DateFormat's calendar.
 662      * @return the time zone associated with the calendar of DateFormat.
 663      * @stable ICU 2.0
 664      */
 665     virtual const TimeZone& getTimeZone(void) const;
 666
 667     /**
 668      * Sets the time zone for the calendar of this DateFormat object. The caller
 669      * no longer owns the TimeZone object and should not delete it after this call.
 670      * @param zoneToAdopt the TimeZone to be adopted.
 671      * @stable ICU 2.0
 672      */
 673     virtual void adoptTimeZone(TimeZone* zoneToAdopt);
 674
 675     /**
 676      * Sets the time zone for the calendar of this DateFormat object.
 677      * @param zone the new time zone.
 678      * @stable ICU 2.0
 679      */
 680     virtual void setTimeZone(const TimeZone& zone);
 681
 682 protected:
 683     /**
 684      * Default constructor.  Creates a DateFormat with no Calendar or NumberFormat
 685      * associated with it.  This constructor depends on the subclasses to fill in
 686      * the calendar and numberFormat fields.
 687      * @stable ICU 2.0
 688      */
 689     DateFormat();
 690
 691     /**
 692      * Copy constructor.
 693      * @stable ICU 2.0
 694      */
 695     DateFormat(const DateFormat&);
 696
 697     /**
 698      * Default assignment operator.
 699      * @stable ICU 2.0
 700      */
 701     DateFormat& operator=(const DateFormat&);
 702
 703     /**
 704      * The calendar that DateFormat uses to produce the time field values needed
 705      * to implement date/time formatting. Subclasses should generally initialize
 706      * this to the default calendar for the locale associated with this DateFormat.
 707      * @stable ICU 2.4
 708      */
 709     Calendar* fCalendar;
 710
 711     /**
 712      * The number formatter that DateFormat uses to format numbers in dates and
 713      * times. Subclasses should generally initialize this to the default number
 714      * format for the locale associated with this DateFormat.
 715      * @stable ICU 2.4
 716      */
 717     NumberFormat* fNumberFormat;
 718
 719 private:
 720     /**
 721      * Gets the date/time formatter with the given formatting styles for the
 722      * given locale.
 723      * @param dateStyle the given date formatting style.
 724      * @param timeStyle the given time formatting style.
 725      * @param inLocale the given locale.
 726      * @return a date/time formatter, or 0 on failure.
 727      */
 728     static DateFormat* U_EXPORT2 create(EStyle timeStyle, EStyle dateStyle, const Locale& inLocale);
 729
 730 public:
 731 #ifndef U_HIDE_OBSOLETE_API
 732     /**
 733      * Field selector for FieldPosition for DateFormat fields.
 734      * @obsolete ICU 3.4 use UDateFormatField instead, since this API will be
 735      * removed in that release
 736      */
 737     enum EField
 738     {
 739         // Obsolete; use UDateFormatField instead
 740         kEraField = UDAT_ERA_FIELD,
 741         kYearField = UDAT_YEAR_FIELD,
 742         kMonthField = UDAT_MONTH_FIELD,
 743         kDateField = UDAT_DATE_FIELD,
 744         kHourOfDay1Field = UDAT_HOUR_OF_DAY1_FIELD,
 745         kHourOfDay0Field = UDAT_HOUR_OF_DAY0_FIELD,
 746         kMinuteField = UDAT_MINUTE_FIELD,
 747         kSecondField = UDAT_SECOND_FIELD,
 748         kMillisecondField = UDAT_FRACTIONAL_SECOND_FIELD,
 749         kDayOfWeekField = UDAT_DAY_OF_WEEK_FIELD,
 750         kDayOfYearField = UDAT_DAY_OF_YEAR_FIELD,
 751         kDayOfWeekInMonthField = UDAT_DAY_OF_WEEK_IN_MONTH_FIELD,
 752         kWeekOfYearField = UDAT_WEEK_OF_YEAR_FIELD,
 753         kWeekOfMonthField = UDAT_WEEK_OF_MONTH_FIELD,
 754         kAmPmField = UDAT_AM_PM_FIELD,
 755         kHour1Field = UDAT_HOUR1_FIELD,
 756         kHour0Field = UDAT_HOUR0_FIELD,
 757         kTimezoneField = UDAT_TIMEZONE_FIELD,
 758         kYearWOYField = UDAT_YEAR_WOY_FIELD,
 759         kDOWLocalField = UDAT_DOW_LOCAL_FIELD,
 760         kExtendedYearField = UDAT_EXTENDED_YEAR_FIELD,
 761         kJulianDayField = UDAT_JULIAN_DAY_FIELD,
 762         kMillisecondsInDayField = UDAT_MILLISECONDS_IN_DAY_FIELD,
 763
 764         // Obsolete; use UDateFormatField instead
 765         ERA_FIELD = UDAT_ERA_FIELD,
 766         YEAR_FIELD = UDAT_YEAR_FIELD,
 767         MONTH_FIELD = UDAT_MONTH_FIELD,
 768         DATE_FIELD = UDAT_DATE_FIELD,
 769         HOUR_OF_DAY1_FIELD = UDAT_HOUR_OF_DAY1_FIELD,
 770         HOUR_OF_DAY0_FIELD = UDAT_HOUR_OF_DAY0_FIELD,
 771         MINUTE_FIELD = UDAT_MINUTE_FIELD,
 772         SECOND_FIELD = UDAT_SECOND_FIELD,
 773         MILLISECOND_FIELD = UDAT_FRACTIONAL_SECOND_FIELD,
 774         DAY_OF_WEEK_FIELD = UDAT_DAY_OF_WEEK_FIELD,
 775         DAY_OF_YEAR_FIELD = UDAT_DAY_OF_YEAR_FIELD,
 776         DAY_OF_WEEK_IN_MONTH_FIELD = UDAT_DAY_OF_WEEK_IN_MONTH_FIELD,
 777         WEEK_OF_YEAR_FIELD = UDAT_WEEK_OF_YEAR_FIELD,
 778         WEEK_OF_MONTH_FIELD = UDAT_WEEK_OF_MONTH_FIELD,
 779         AM_PM_FIELD = UDAT_AM_PM_FIELD,
 780         HOUR1_FIELD = UDAT_HOUR1_FIELD,
 781         HOUR0_FIELD = UDAT_HOUR0_FIELD,
 782         TIMEZONE_FIELD = UDAT_TIMEZONE_FIELD
 783     };
 784 #endif  /* U_HIDE_OBSOLETE_API */
 785 };
 786
 787 inline UnicodeString&
 788 DateFormat::format(const Formattable& obj,
 789                    UnicodeString& appendTo,
 790                    UErrorCode& status) const {
 791     return Format::format(obj, appendTo, status);
 792 }
 793 U_NAMESPACE_END
 794
 795 #endif /* #if !UCONFIG_NO_FORMATTING */
 796
 797 #endif // _DATEFMT
 798 //eof