000

/*
* Copyright (C) 1997-2012, International Business Machines Corporation and
* others. All Rights Reserved.
*******************************************************************************
*
* File SMPDTFMT.H
*
* Modification History:
*
*   Date        Name        Description
*   02/19/97    aliu        Converted from java.
*   07/09/97    helena      Make ParsePosition into a class.
*   07/21/98    stephen     Added GMT_PLUS, GMT_MINUS
*                            Changed setTwoDigitStartDate to set2DigitYearStart
*                            Changed getTwoDigitStartDate to get2DigitYearStart
*                            Removed subParseLong
*                            Removed getZoneIndex (added in DateFormatSymbols)
*   06/14/99    stephen     Removed fgTimeZoneDataSuffix
*   10/14/99    aliu        Updated class doc to describe 2-digit year parsing
*                           {j28 4182066}.
*******************************************************************************
*/

#ifndef SMPDTFMT_H
#define SMPDTFMT_H

#include "unicode/utypes.h"

/**
 * \file
 * \brief C++ API: Format and parse dates in a language-independent manner.
 */

#if !UCONFIG_NO_FORMATTING

#include "unicode/datefmt.h"
#include "unicode/udisplaycontext.h"

U_NAMESPACE_BEGIN

class DateFormatSymbols;
class DateFormat;
class MessageFormat;
class FieldPositionHandler;
class TimeZoneFormat;

/**
 *
 * SimpleDateFormat is a concrete class for formatting and parsing dates in a
 * language-independent manner. It allows for formatting (millis -> text),
 * parsing (text -> millis), and normalization. Formats/Parses a date or time,
 * which is the standard milliseconds since 24:00 GMT, Jan 1, 1970.
 * 
 * Clients are encouraged to create a date-time formatter using DateFormat::getInstance(),
 * getDateInstance(), getDateInstance(), or getDateTimeInstance() rather than
 * explicitly constructing an instance of SimpleDateFormat. This way, the client
 * is guaranteed to get an appropriate formatting pattern for whatever locale the
 * program is running in. However, if the client needs something more unusual than
 * the default patterns in the locales, he can construct a SimpleDateFormat directly
 * and give it an appropriate pattern (or use one of the factory methods on DateFormat
 * and modify the pattern after the fact with toPattern() and applyPattern().
 * 
 * Date/Time format syntax:
 * 
 * The date/time format is specified by means of a string time pattern. In this
 * pattern, all ASCII letters are reserved as pattern letters, which are defined
 * as the following:
 * <pre>
 * \code
 * Symbol Meaning Presentation Example
 * ------ ------- ------------ -------
 * G era designator (Text) AD
 * y year (Number) 1996
 * Y year (week of year) (Number) 1997
 * u extended year (Number) 4601
 * U cyclic year name (Text,NumFallback) ren-chen (29)
 * Q Quarter (Text & Number) Q2 & 02
 * M month in year (Text & Number) July & 07
 * d day in month (Number) 10
 * h hour in am/pm (1~12) (Number) 12
 * H hour in day (0~23) (Number) 0
 * m minute in hour (Number) 30
 * s second in minute (Number) 55
 * S fractional second (Number) 978
 * (maximum resolution of SSS; truncated if shorter, zero-padded if longer)
 * E day of week (Text) Tuesday
 * e day of week (local 1~7) (Text & Number) Tues & 2
 * D day in year (Number) 189
 * F day of week in month (Number) 2 (2nd Wed in July)
 * w week in year (Number) 27
 * W week in month (Number) 2
 * a am/pm marker (Text) PM
 * k hour in day (1~24) (Number) 24
 * K hour in am/pm (0~11) (Number) 0
 * z time zone (Text) PST
 * zzzz time zone (Text) Pacific Standard Time
 * Z time zone (RFC 822) (Number) -0800
 * ZZZZ time zone (RFC 822) (Text & Number) GMT-08:00
 * ZZZZZ time zone (ISO 8601) (Text & Number) -08:00 & Z
 * v time zone (generic) (Text) PT
 * vvvv time zone (generic) (Text) Pacific Time
 * V time zone (abreviation) (Text) PST
 * VVVV time zone (location) (Text) United States Time (Los Angeles)
 * g Julian day (Number) 2451334
 * A milliseconds in day (Number) 69540000
 * q stand alone quarter (Text & Number) Q2 & 02
 * L stand alone month (Text & Number) July & 07
 * c stand alone day of week (Text & Number) Tuesday & 2
 * ' escape for text (Delimiter) 'Date='
 * '' single quote (Literal) 'o''clock'
 * \endcode
 * </pre>
 * The count of pattern letters determine the format.
 * 
 * (Text): 4 or more, use full form, &lt;4, use short or abbreviated form if it
 * exists. (e.g., "EEEE" produces "Monday", "EEE" produces "Mon")
 * 
 * (Number): the minimum number of digits. Shorter numbers are zero-padded to
 * this amount (e.g. if "m" produces "6", "mm" produces "06"). Year is handled
 * specially; that is, if the count of 'y' is 2, the Year will be truncated to 2 digits.
 * (e.g., if "yyyy" produces "1997", "yy" produces "97".)
 * Unlike other fields, fractional seconds are padded on the right with zero.
 * 
 * (Text & Number): 3 or over, use text, otherwise use number. (e.g., "M" produces "1",
 * "MM" produces "01", "MMM" produces "Jan", and "MMMM" produces "January".)
 * 
 * (Text,NumFallback): Behaves like Text if there is supporting data, like
 * Number otherwise.
 * 
 * Any characters in the pattern that are not in the ranges of ['a'..'z'] and
 * ['A'..'Z'] will be treated as quoted text. For instance, characters
 * like ':', '.', ' ', '#' and '@' will appear in the resulting time text
 * even they are not embraced within single quotes.
 * 
 * A pattern containing any invalid pattern letter will result in a failing
 * UErrorCode result during formatting or parsing.
 * 
 * Examples using the US locale:
 * <pre>
 * \code
 * Format Pattern Result
 * -------------- -------
 * "yyyy.MM.dd G 'at' HH:mm:ss vvvv" ->> 1996.07.10 AD at 15:08:56 Pacific Time
 * "EEE, MMM d, ''yy" ->> Wed, July 10, '96
 * "h:mm a" ->> 12:08 PM
 * "hh 'o''clock' a, zzzz" ->> 12 o'clock PM, Pacific Daylight Time
 * "K:mm a, vvv" ->> 0:00 PM, PT
 * "yyyyy.MMMMM.dd GGG hh:mm aaa" ->> 1996.July.10 AD 12:08 PM
 * \endcode
 * </pre>
 * Code Sample:
 * <pre>
 * \code
 * UErrorCode success = U_ZERO_ERROR;
 * SimpleTimeZone* pdt = new SimpleTimeZone(-8 * 60 * 60 * 1000, "PST");
 * pdt->setStartRule( Calendar::APRIL, 1, Calendar::SUNDAY, 2*60*60*1000);
 * pdt->setEndRule( Calendar::OCTOBER, -1, Calendar::SUNDAY, 2*60*60*1000);
 *
 * // Format the current time.
 * SimpleDateFormat* formatter
 * = new SimpleDateFormat ("yyyy.MM.dd G 'at' hh:mm:ss a zzz", success );
 * GregorianCalendar cal(success);
 * UDate currentTime_1 = cal.getTime(success);
 * FieldPosition fp(0);
 * UnicodeString dateString;
 * formatter->format( currentTime_1, dateString, fp );
 * cout << "result: " << dateString << endl;
 *
 * // Parse the previous string back into a Date.
 * ParsePosition pp(0);
 * UDate currentTime_2 = formatter->parse(dateString, pp );
 * \endcode
 * </pre>
 * In the above example, the time value "currentTime_2" obtained from parsing
 * will be equal to currentTime_1. However, they may not be equal if the am/pm
 * marker 'a' is left out from the format pattern while the "hour in am/pm"
 * pattern symbol is used. This information loss can happen when formatting the
 * time in PM.
 *
 * 
 * When parsing a date string using the abbreviated year pattern ("y" or "yy"),
 * SimpleDateFormat must interpret the abbreviated year
 * relative to some century. It does this by adjusting dates to be
 * within 80 years before and 20 years after the time the SimpleDateFormat
 * instance is created. For example, using a pattern of "MM/dd/yy" and a
 * SimpleDateFormat instance created on Jan 1, 1997, the string
 * "01/11/12" would be interpreted as Jan 11, 2012 while the string "05/04/64"
 * would be interpreted as May 4, 1964.
 * During parsing, only strings consisting of exactly two digits, as defined by
 * <code>Unicode::isDigit()</code>, will be parsed into the default century.
 * Any other numeric string, such as a one digit string, a three or more digit
 * string, or a two digit string that isn't all digits (for example, "-1"), is
 * interpreted literally. So "01/02/3" or "01/02/003" are parsed (for the
 * Gregorian calendar), using the same pattern, as Jan 2, 3 AD. Likewise (but
 * only in lenient parse mode, the default) "01/02/-3" is parsed as Jan 2, 4 BC.
 *
 * 
 * If the year pattern has more than two 'y' characters, the year is
 * interpreted literally, regardless of the number of digits. So using the
 * pattern "MM/dd/yyyy", "01/11/12" parses to Jan 11, 12 A.D.
 *
 * 
 * When numeric fields abut one another directly, with no intervening delimiter
 * characters, they constitute a run of abutting numeric fields. Such runs are
 * parsed specially. For example, the format "HHmmss" parses the input text
 * "123456" to 12:34:56, parses the input text "12345" to 1:23:45, and fails to
 * parse "1234". In other words, the leftmost field of the run is flexible,
 * while the others keep a fixed width. If the parse fails anywhere in the run,
 * then the leftmost field is shortened by one character, and the entire run is
 * parsed again. This is repeated until either the parse succeeds or the
 * leftmost field is one character in length. If the parse still fails at that
 * point, the parse of the run fails.
 *
 * 
 * For time zones that have no names, SimpleDateFormat uses strings GMT+hours:minutes or
 * GMT-hours:minutes.
 * 
 * The calendar defines what is the first day of the week, the first week of the
 * year, whether hours are zero based or not (0 vs 12 or 24), and the timezone.
 * There is one common number format to handle all the numbers; the digit count
 * is handled programmatically according to the pattern.
 *
 * User subclasses are not supported. While clients may write
 * subclasses, such code will not necessarily work and will not be
 * guaranteed to work stably from release to release.
 */
class U_I18N_API SimpleDateFormat: public DateFormat {
public:
 /**
 * Construct a SimpleDateFormat using the default pattern for the default
 * locale.
 * 
 * [Note:] Not all locales support SimpleDateFormat; for full generality,
 * use the factory methods in the DateFormat class.
 * @param status Output param set to success/failure code.
 * @stable ICU 2.0
 */
 SimpleDateFormat(UErrorCode& status);

/**
 * Construct a SimpleDateFormat using the given pattern and the default locale.
 * The locale is used to obtain the symbols used in formatting (e.g., the
 * names of the months), but not to provide the pattern.
 * 
 * [Note:] Not all locales support SimpleDateFormat; for full generality,
 * use the factory methods in the DateFormat class.
 * @param pattern the pattern for the format.
 * @param status Output param set to success/failure code.
 * @stable ICU 2.0
 */
 SimpleDateFormat(const UnicodeString& pattern,
 UErrorCode& status);

/**
 * Construct a SimpleDateFormat using the given pattern, numbering system override, and the default locale.
 * The locale is used to obtain the symbols used in formatting (e.g., the
 * names of the months), but not to provide the pattern.
 * 
 * A numbering system override is a string containing either the name of a known numbering system,
 * or a set of field and numbering system pairs that specify which fields are to be formattied with
 * the alternate numbering system. For example, to specify that all numeric fields in the specified
 * date or time pattern are to be rendered using Thai digits, simply specify the numbering system override
 * as "thai". To specify that just the year portion of the date be formatted using Hebrew numbering,
 * use the override string "y=hebrew". Numbering system overrides can be combined using a semi-colon
 * character in the override string, such as "d=decimal;M=arabic;y=hebrew", etc.
 *
 * 
 * [Note:] Not all locales support SimpleDateFormat; for full generality,
 * use the factory methods in the DateFormat class.
 * @param pattern the pattern for the format.
 * @param override the override string.
 * @param status Output param set to success/failure code.
 * @stable ICU 4.2
 */
 SimpleDateFormat(const UnicodeString& pattern,
 const UnicodeString& override,
 UErrorCode& status);

/**
 * Construct a SimpleDateFormat using the given pattern and locale.
 * The locale is used to obtain the symbols used in formatting (e.g., the
 * names of the months), but not to provide the pattern.
 * 
 * [Note:] Not all locales support SimpleDateFormat; for full generality,
 * use the factory methods in the DateFormat class.
 * @param pattern the pattern for the format.
 * @param locale the given locale.
 * @param status Output param set to success/failure code.
 * @stable ICU 2.0
 */
 SimpleDateFormat(const UnicodeString& pattern,
 const Locale& locale,
 UErrorCode& status);

/**
 * Construct a SimpleDateFormat using the given pattern, numbering system override, and locale.
 * The locale is used to obtain the symbols used in formatting (e.g., the
 * names of the months), but not to provide the pattern.
 * 
 * A numbering system override is a string containing either the name of a known numbering system,
 * or a set of field and numbering system pairs that specify which fields are to be formattied with
 * the alternate numbering system. For example, to specify that all numeric fields in the specified
 * date or time pattern are to be rendered using Thai digits, simply specify the numbering system override
 * as "thai". To specify that just the year portion of the date be formatted using Hebrew numbering,
 * use the override string "y=hebrew". Numbering system overrides can be combined using a semi-colon
 * character in the override string, such as "d=decimal;M=arabic;y=hebrew", etc.
 * 
 * [Note:] Not all locales support SimpleDateFormat; for full generality,
 * use the factory methods in the DateFormat class.
 * @param pattern the pattern for the format.
 * @param override the numbering system override.
 * @param locale the given locale.
 * @param status Output param set to success/failure code.
 * @stable ICU 4.2
 */
 SimpleDateFormat(const UnicodeString& pattern,
 const UnicodeString& override,
 const Locale& locale,
 UErrorCode& status);

/**
     * Construct a SimpleDateFormat using the given pattern and locale-specific
     * symbol data.  The formatter takes ownership of the DateFormatSymbols object;
     * the caller is no longer responsible for deleting it.
     * @param pattern           the given pattern for the format.
     * @param formatDataToAdopt the symbols to be adopted.
     * @param status            Output param set to success/faulure code.
     * @stable ICU 2.0
     */
    SimpleDateFormat(const UnicodeString& pattern,
                     DateFormatSymbols* formatDataToAdopt,
                     UErrorCode& status);

/**
     * Construct a SimpleDateFormat using the given pattern and locale-specific
     * symbol data.  The DateFormatSymbols object is NOT adopted; the caller
     * remains responsible for deleting it.
     * @param pattern           the given pattern for the format.
     * @param formatData        the formatting symbols to be use.
     * @param status            Output param set to success/faulure code.
     * @stable ICU 2.0
     */
    SimpleDateFormat(const UnicodeString& pattern,
                     const DateFormatSymbols& formatData,
                     UErrorCode& status);

/**
     * Copy constructor.
     * @stable ICU 2.0
     */
    SimpleDateFormat(const SimpleDateFormat&);

/**
     * Assignment operator.
     * @stable ICU 2.0
     */
    SimpleDateFormat& operator=(const SimpleDateFormat&);

/**
     * Destructor.
     * @stable ICU 2.0
     */
    virtual ~SimpleDateFormat();

/**
     * Clone this Format object polymorphically. The caller owns the result and
     * should delete it when done.
     * @return    A copy of the object.
     * @stable ICU 2.0
     */
    virtual Format* clone(void) const;

/**
     * Return true if the given Format objects are semantically equal. Objects
     * of different subclasses are considered unequal.
     * @param other    the object to be compared with.
     * @return         true if the given Format objects are semantically equal.
     * @stable ICU 2.0
     */
    virtual UBool operator==(const Format& other) const;

using DateFormat::format;

/**
 * Format a date or time, which is the standard millis since 24:00 GMT, Jan
 * 1, 1970. Overrides DateFormat pure virtual method.
 * 
 * Example: using the US locale: "yyyy.MM.dd e 'at' HH:mm:ss zzz" ->>
 * 1996.07.10 AD at 15:08:56 PDT
 *
 * @param cal Calendar set to the date and time to be formatted
 * into a date/time string.
 * @param appendTo Output parameter to receive result.
 * Result is appended to existing contents.
 * @param pos The formatting position. On input: an alignment field,
 * if desired. On output: the offsets of the alignment field.
 * @return Reference to 'appendTo' parameter.
 * @stable ICU 2.1
 */
 virtual UnicodeString& format( Calendar& cal,
 UnicodeString& appendTo,
 FieldPosition& pos) const;

/**
 * Format a date or time, which is the standard millis since 24:00 GMT, Jan
 * 1, 1970. Overrides DateFormat pure virtual method.
 * 
 * Example: using the US locale: "yyyy.MM.dd e 'at' HH:mm:ss zzz" ->>
 * 1996.07.10 AD at 15:08:56 PDT
 *
 * @param cal Calendar set to the date and time to be formatted
 * into a date/time string.
 * @param appendTo Output parameter to receive result.
 * Result is appended to existing contents.
 * @param posIter On return, can be used to iterate over positions
 * of fields generated by this format call. Field values
 * are defined in UDateFormatField.
 * @param status Input/output param set to success/failure code.
 * @return Reference to 'appendTo' parameter.
 * @stable ICU 4.4
 */
 virtual UnicodeString& format( Calendar& cal,
 UnicodeString& appendTo,
 FieldPositionIterator* posIter,
 UErrorCode& status) const;

/**
 * Format a date or time, which is the standard millis since 24:00 GMT, Jan
 * 1, 1970. Overrides DateFormat pure virtual method.
 * 
 * Example: using the US locale: "yyyy.MM.dd e 'at' HH:mm:ss zzz" ->>
 * 1996.07.10 AD at 15:08:56 PDT
 *
 * @param obj A Formattable containing the date-time value to be formatted
 * into a date-time string. If the type of the Formattable
 * is a numeric type, it is treated as if it were an
 * instance of Date.
 * @param appendTo Output parameter to receive result.
 * Result is appended to existing contents.
 * @param pos The formatting position. On input: an alignment field,
 * if desired. On output: the offsets of the alignment field.
 * @param status Input/output param set to success/failure code.
 * @return Reference to 'appendTo' parameter.
 * @stable ICU 2.0
 */
 virtual UnicodeString& format( const Formattable& obj,
 UnicodeString& appendTo,
 FieldPosition& pos,
 UErrorCode& status) const;

/**
 * Format a date or time, which is the standard millis since 24:00 GMT, Jan
 * 1, 1970. Overrides DateFormat pure virtual method.
 * 
 * Example: using the US locale: "yyyy.MM.dd e 'at' HH:mm:ss zzz" ->>
 * 1996.07.10 AD at 15:08:56 PDT
 *
 * @param obj A Formattable containing the date-time value to be formatted
 * into a date-time string. If the type of the Formattable
 * is a numeric type, it is treated as if it were an
 * instance of Date.
 * @param appendTo Output parameter to receive result.
 * Result is appended to existing contents.
 * @param posIter On return, can be used to iterate over positions
 * of fields generated by this format call. Field values
 * are defined in UDateFormatField.
 * @param status Input/output param set to success/failure code.
 * @return Reference to 'appendTo' parameter.
 * @stable ICU 4.4
 */
 virtual UnicodeString& format( const Formattable& obj,
 UnicodeString& appendTo,
 FieldPositionIterator* posIter,
 UErrorCode& status) const;

/**
     * Redeclared DateFormat method.
     * @param date          the Date value to be formatted.
     * @param appendTo      Output parameter to receive result.
     *                      Result is appended to existing contents.
     * @param fieldPosition The formatting position. On input: an alignment field,
     *                      if desired. On output: the offsets of the alignment field.
     * @return              Reference to 'appendTo' parameter.
     * @stable ICU 2.1
     */
    UnicodeString& format(UDate date,
                          UnicodeString& appendTo,
                          FieldPosition& fieldPosition) const;

/**
     * Redeclared DateFormat method.
     * @param date          the Date value to be formatted.
     * @param appendTo      Output parameter to receive result.
     *                      Result is appended to existing contents.
     * @param posIter       On return, can be used to iterate over positions
     *                      of fields generated by this format call.  Field values
     *                      are defined in UDateFormatField.
     * @param status        Input/output param set to success/failure code.
     * @return              Reference to 'appendTo' parameter.
     * @stable ICU 4.4
     */
    UnicodeString& format(UDate date,
                          UnicodeString& appendTo,
                          FieldPositionIterator* posIter,
                          UErrorCode& status) const;

/**
     * Redeclared DateFormat method.
     * @param obj       Object to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param status    Input/output success/failure code.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.0
     */
    UnicodeString& format(const Formattable& obj,
                          UnicodeString& appendTo,
                          UErrorCode& status) const;

/**
     * Redeclared DateFormat method.
     * @param date      Date value to be formatted.
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @return          Reference to 'appendTo' parameter.
     * @stable ICU 2.0
     */
    UnicodeString& format(UDate date, UnicodeString& appendTo) const;

/**
 * Parse a date/time string beginning at the given parse position. For
 * example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
 * that is equivalent to Date(837039928046).
 * 
 * By default, parsing is lenient: If the input is not in the form used by
 * this object's format method but can still be parsed as a date, then the
 * parse succeeds. Clients may insist on strict adherence to the format by
 * calling setLenient(false).
 * @see DateFormat::setLenient(boolean)
 *
 * @param text The date/time string to be parsed
 * @param cal A Calendar set on input to the date and time to be used for
 * missing values in the date/time string being parsed, and set
 * on output to the parsed date/time. When the calendar type is
 * different from the internal calendar held by this SimpleDateFormat
 * instance, the internal calendar will be cloned to a work
 * calendar set to the same milliseconds and time zone as the
 * cal parameter, field values will be parsed based on the work
 * calendar, then the result (milliseconds and time zone) will
 * be set in this calendar.
 * @param pos On input, the position at which to start parsing; on
 * output, the position at which parsing terminated, or the
 * start position if the parse failed.
 * @stable ICU 2.1
 */
 virtual void parse( const UnicodeString& text,
 Calendar& cal,
 ParsePosition& pos) const;

/**
 * Parse a date/time string starting at the given parse position. For
 * example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
 * that is equivalent to Date(837039928046).
 * 
 * By default, parsing is lenient: If the input is not in the form used by
 * this object's format method but can still be parsed as a date, then the
 * parse succeeds. Clients may insist on strict adherence to the format by
 * calling setLenient(false).
 * @see DateFormat::setLenient(boolean)
 * 
 * Note that the normal date formats associated with some calendars - such
 * as the Chinese lunar calendar - do not specify enough fields to enable
 * dates to be parsed unambiguously. In the case of the Chinese lunar
 * calendar, while the year within the current 60-year cycle is specified,
 * the number of such cycles since the start date of the calendar (in the
 * ERA field of the Calendar object) is not normally part of the format,
 * and parsing may assume the wrong era. For cases such as this it is
 * recommended that clients parse using the method
 * parse(const UnicodeString&, Calendar& cal, ParsePosition&)
 * with the Calendar passed in set to the current date, or to a date
 * within the era/cycle that should be assumed if absent in the format.
 *
 * @param text The date/time string to be parsed
 * @param pos On input, the position at which to start parsing; on
 * output, the position at which parsing terminated, or the
 * start position if the parse failed.
 * @return A valid UDate if the input could be parsed.
 * @stable ICU 2.0
 */
 UDate parse( const UnicodeString& text,
 ParsePosition& pos) const;

/**
 * Parse a date/time string. For example, a time text "07/10/96 4:5 PM, PDT"
 * will be parsed into a UDate that is equivalent to Date(837039928046).
 * Parsing begins at the beginning of the string and proceeds as far as
 * possible. Assuming no parse errors were encountered, this function
 * doesn't return any information about how much of the string was consumed
 * by the parsing. If you need that information, use the version of
 * parse() that takes a ParsePosition.
 * 
 * By default, parsing is lenient: If the input is not in the form used by
 * this object's format method but can still be parsed as a date, then the
 * parse succeeds. Clients may insist on strict adherence to the format by
 * calling setLenient(false).
 * @see DateFormat::setLenient(boolean)
 * 
 * Note that the normal date formats associated with some calendars - such
 * as the Chinese lunar calendar - do not specify enough fields to enable
 * dates to be parsed unambiguously. In the case of the Chinese lunar
 * calendar, while the year within the current 60-year cycle is specified,
 * the number of such cycles since the start date of the calendar (in the
 * ERA field of the Calendar object) is not normally part of the format,
 * and parsing may assume the wrong era. For cases such as this it is
 * recommended that clients parse using the method
 * parse(const UnicodeString&, Calendar& cal, ParsePosition&)
 * with the Calendar passed in set to the current date, or to a date
 * within the era/cycle that should be assumed if absent in the format.
 *
 * @param text The date/time string to be parsed into a UDate value.
 * @param status Filled in with U_ZERO_ERROR if the parse was successful, and with
 * an error value if there was a parse error.
 * @return A valid UDate if the input could be parsed.
 * @stable ICU 2.0
 */
 virtual UDate parse( const UnicodeString& text,
 UErrorCode& status) const;

/**
 * Set the start UDate used to interpret two-digit year strings.
 * When dates are parsed having 2-digit year strings, they are placed within
 * a assumed range of 100 years starting on the two digit start date. For
 * example, the string "24-Jan-17" may be in the year 1817, 1917, 2017, or
 * some other year. SimpleDateFormat chooses a year so that the resultant
 * date is on or after the two digit start date and within 100 years of the
 * two digit start date.
 * 
 * By default, the two digit start date is set to 80 years before the current
 * time at which a SimpleDateFormat object is created.
 * @param d start UDate used to interpret two-digit year strings.
 * @param status Filled in with U_ZERO_ERROR if the parse was successful, and with
 * an error value if there was a parse error.
 * @stable ICU 2.0
 */
 virtual void set2DigitYearStart(UDate d, UErrorCode& status);

/**
 * Get the start UDate used to interpret two-digit year strings.
 * When dates are parsed having 2-digit year strings, they are placed within
 * a assumed range of 100 years starting on the two digit start date. For
 * example, the string "24-Jan-17" may be in the year 1817, 1917, 2017, or
 * some other year. SimpleDateFormat chooses a year so that the resultant
 * date is on or after the two digit start date and within 100 years of the
 * two digit start date.
 * 
 * By default, the two digit start date is set to 80 years before the current
 * time at which a SimpleDateFormat object is created.
 * @param status Filled in with U_ZERO_ERROR if the parse was successful, and with
 * an error value if there was a parse error.
 * @stable ICU 2.0
 */
 UDate get2DigitYearStart(UErrorCode& status) const;

/**
     * Return a pattern string describing this date format.
     * @param result Output param to receive the pattern.
     * @return       A reference to 'result'.
     * @stable ICU 2.0
     */
    virtual UnicodeString& toPattern(UnicodeString& result) const;

/**
     * Return a localized pattern string describing this date format.
     * In most cases, this will return the same thing as toPattern(),
     * but a locale can specify characters to use in pattern descriptions
     * in place of the ones described in this class's class documentation.
     * (Presumably, letters that would be more mnemonic in that locale's
     * language.)  This function would produce a pattern using those
     * letters.
     *
     * @param result    Receives the localized pattern.
     * @param status    Output param set to success/failure code on
     *                  exit. If the pattern is invalid, this will be
     *                  set to a failure result.
     * @return          A reference to 'result'.
     * @stable ICU 2.0
     */
    virtual UnicodeString& toLocalizedPattern(UnicodeString& result,
                                              UErrorCode& status) const;

/**
     * Apply the given unlocalized pattern string to this date format.
     * (i.e., after this call, this formatter will format dates according to
     * the new pattern)
     *
     * @param pattern   The pattern to be applied.
     * @stable ICU 2.0
     */
    virtual void applyPattern(const UnicodeString& pattern);

/**
     * Apply the given localized pattern string to this date format.
     * (see toLocalizedPattern() for more information on localized patterns.)
     *
     * @param pattern   The localized pattern to be applied.
     * @param status    Output param set to success/failure code on
     *                  exit. If the pattern is invalid, this will be
     *                  set to a failure result.
     * @stable ICU 2.0
     */
    virtual void applyLocalizedPattern(const UnicodeString& pattern,
                                       UErrorCode& status);

/**
     * Gets the date/time formatting symbols (this is an object carrying
     * the various strings and other symbols used in formatting: e.g., month
     * names and abbreviations, time zone names, AM/PM strings, etc.)
     * @return a copy of the date-time formatting data associated
     * with this date-time formatter.
     * @stable ICU 2.0
     */
    virtual const DateFormatSymbols* getDateFormatSymbols(void) const;

/**
     * Set the date/time formatting symbols.  The caller no longer owns the
     * DateFormatSymbols object and should not delete it after making this call.
     * @param newFormatSymbols the given date-time formatting symbols to copy.
     * @stable ICU 2.0
     */
    virtual void adoptDateFormatSymbols(DateFormatSymbols* newFormatSymbols);

/**
     * Set the date/time formatting data.
     * @param newFormatSymbols the given date-time formatting symbols to copy.
     * @stable ICU 2.0
     */
    virtual void setDateFormatSymbols(const DateFormatSymbols& newFormatSymbols);

/**
 * Return the class ID for this class. This is useful only for comparing to
 * a return value from getDynamicClassID(). For example:
 * <pre>
 * . Base* polymorphic_pointer = createPolymorphicObject();
 * . if (polymorphic_pointer->getDynamicClassID() ==
 * . erived::getStaticClassID()) ...
 * </pre>
 * @return The class ID for all objects of this class.
 * @stable ICU 2.0
 */
 static UClassID U_EXPORT2 getStaticClassID(void);

/**
     * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. This
     * method is to implement a simple version of RTTI, since not all C++
     * compilers support genuine RTTI. Polymorphic operator==() and clone()
     * methods call this method.
     *
     * @return          The class ID for this object. All objects of a
     *                  given class have the same class ID.  Objects of
     *                  other classes have different class IDs.
     * @stable ICU 2.0
     */
    virtual UClassID getDynamicClassID(void) const;

/**
     * Set the calendar to be used by this date format. Initially, the default
     * calendar for the specified or default locale is used.  The caller should
     * not delete the Calendar object after it is adopted by this call.
     * Adopting a new calendar will change to the default symbols.
     *
     * @param calendarToAdopt    Calendar object to be adopted.
     * @stable ICU 2.0
     */
    virtual void adoptCalendar(Calendar* calendarToAdopt);

/* Cannot use #ifndef U_HIDE_INTERNAL_API for the following draft method since it is virtual */
    /**
     * Set a particular UDisplayContext value in the formatter, such as
     * UDISPCTX_CAPITALIZATION_FOR_STANDALONE.
     * @param value The UDisplayContext value to set.
     * @param status Input/output status. If at entry this indicates a failure
     *               status, the function will do nothing; otherwise this will be
     *               updated with any new status from the function. 
     * @internal ICU 50 technology preview
     */
    virtual void setContext(UDisplayContext value, UErrorCode& status);

/* Cannot use #ifndef U_HIDE_INTERNAL_API for the following draft method since it is virtual */
    /**
     * Get the formatter's UDisplayContext value for the specified UDisplayContextType,
     * such as UDISPCTX_TYPE_CAPITALIZATION.
     * @param type The UDisplayContextType whose value to return
     * @param status Input/output status. If at entry this indicates a failure
     *               status, the function will do nothing; otherwise this will be
     *               updated with any new status from the function. 
     * @return The UDisplayContextValue for the specified type.
     * @internal ICU 50 technology preview
     */
    virtual UDisplayContext getContext(UDisplayContextType type, UErrorCode& status) const;

/* Cannot use #ifndef U_HIDE_INTERNAL_API for the following methods since they are virtual */
    /**
     * Sets the TimeZoneFormat to be used by this date/time formatter.
     * The caller should not delete the TimeZoneFormat object after
     * it is adopted by this call.
     * @param timeZoneFormatToAdopt The TimeZoneFormat object to be adopted.
     * @internal ICU 49 technology preview
     */
    virtual void adoptTimeZoneFormat(TimeZoneFormat* timeZoneFormatToAdopt);

/**
     * Sets the TimeZoneFormat to be used by this date/time formatter.
     * @param newTimeZoneFormat The TimeZoneFormat object to copy.
     * @internal ICU 49 technology preview
     */
    virtual void setTimeZoneFormat(const TimeZoneFormat& newTimeZoneFormat);

/**
     * Gets the time zone format object associated with this date/time formatter.
     * @return the time zone format associated with this date/time formatter.
     * @internal ICU 49 technology preview
     */
    virtual const TimeZoneFormat* getTimeZoneFormat(void) const;

#ifndef U_HIDE_INTERNAL_API
    /**
     * This is for ICU internal use only. Please do not use.
     * Check whether the 'field' is smaller than all the fields covered in
     * pattern, return TRUE if it is. The sequence of calendar field,
     * from large to small is: ERA, YEAR, MONTH, DATE, AM_PM, HOUR, MINUTE,...
     * @param field    the calendar field need to check against
     * @return         TRUE if the 'field' is smaller than all the fields
     *                 covered in pattern. FALSE otherwise.
     * @internal ICU 4.0
     */
    UBool isFieldUnitIgnored(UCalendarDateFields field) const;

/**
     * This is for ICU internal use only. Please do not use.
     * Check whether the 'field' is smaller than all the fields covered in
     * pattern, return TRUE if it is. The sequence of calendar field,
     * from large to small is: ERA, YEAR, MONTH, DATE, AM_PM, HOUR, MINUTE,...
     * @param pattern  the pattern to check against
     * @param field    the calendar field need to check against
     * @return         TRUE if the 'field' is smaller than all the fields
     *                 covered in pattern. FALSE otherwise.
     * @internal ICU 4.0
     */
    static UBool isFieldUnitIgnored(const UnicodeString& pattern,
                                    UCalendarDateFields field);

/**
     * This is for ICU internal use only. Please do not use.
     * Get the locale of this simple date formatter.
     * It is used in DateIntervalFormat.
     *
     * @return   locale in this simple date formatter
     * @internal ICU 4.0
     */
    const Locale& getSmpFmtLocale(void) const;
#endif  /* U_HIDE_INTERNAL_API */

private:
    friend class DateFormat;

void initializeDefaultCentury(void);

SimpleDateFormat(); // default constructor not implemented

/**
     * Used by the DateFormat factory methods to construct a SimpleDateFormat.
     * @param timeStyle the time style.
     * @param dateStyle the date style.
     * @param locale    the given locale.
     * @param status    Output param set to success/failure code on
     *                  exit.
     */
    SimpleDateFormat(EStyle timeStyle, EStyle dateStyle, const Locale& locale, UErrorCode& status);

/**
     * Construct a SimpleDateFormat for the given locale.  If no resource data
     * is available, create an object of last resort, using hard-coded strings.
     * This is an internal method, called by DateFormat.  It should never fail.
     * @param locale    the given locale.
     * @param status    Output param set to success/failure code on
     *                  exit.
     */
    SimpleDateFormat(const Locale& locale, UErrorCode& status); // Use default pattern

/**
     * Hook called by format(... FieldPosition& ...) and format(...FieldPositionIterator&...)
     */
    UnicodeString& _format(Calendar& cal, UnicodeString& appendTo, FieldPositionHandler& handler, UErrorCode& status) const;

/**
     * Called by format() to format a single field.
     *
     * @param appendTo  Output parameter to receive result.
     *                  Result is appended to existing contents.
     * @param ch        The format character we encountered in the pattern.
     * @param count     Number of characters in the current pattern symbol (e.g.,
     *                  "yyyy" in the pattern would result in a call to this function
     *                  with ch equal to 'y' and count equal to 4)
     * @param capitalizationContext Capitalization context for this date format.
     * @param fieldNum  Zero-based numbering of current field within the overall format.
     * @param handler   Records information about field positions.
     * @param cal       Calendar to use
     * @param status    Receives a status code, which will be U_ZERO_ERROR if the operation
     *                  succeeds.
     */
    void subFormat(UnicodeString &appendTo,
                   UChar ch,
                   int32_t count,
                   UDisplayContext capitalizationContext,
                   int32_t fieldNum,
                   FieldPositionHandler& handler,
                   Calendar& cal,
                   UErrorCode& status) const; // in case of illegal argument

/**
     * Used by subFormat() to format a numeric value.
     * Appends to toAppendTo a string representation of "value"
     * having a number of digits between "minDigits" and
     * "maxDigits".  Uses the DateFormat's NumberFormat.
     *
     * @param currentNumberFormat 
     * @param appendTo  Output parameter to receive result.
     *                  Formatted number is appended to existing contents.
     * @param value     Value to format.
     * @param minDigits Minimum number of digits the result should have
     * @param maxDigits Maximum number of digits the result should have
     */
    void zeroPaddingNumber(NumberFormat *currentNumberFormat,
                           UnicodeString &appendTo,
                           int32_t value,
                           int32_t minDigits,
                           int32_t maxDigits) const;

/**
     * Return true if the given format character, occuring count
     * times, represents a numeric field.
     */
    static UBool isNumeric(UChar formatChar, int32_t count);

/**
     * Returns TRUE if the patternOffset is at the start of a numeric field.
     */
    static UBool isAtNumericField(const UnicodeString &pattern, int32_t patternOffset);

/**
     * Returns TRUE if the patternOffset is right after a non-numeric field.
     */
    static UBool isAfterNonNumericField(const UnicodeString &pattern, int32_t patternOffset);

/**
     * initializes fCalendar from parameters.  Returns fCalendar as a convenience.
     * @param adoptZone  Zone to be adopted, or NULL for TimeZone::createDefault().
     * @param locale Locale of the calendar
     * @param status Error code
     * @return the newly constructed fCalendar
     */
    Calendar *initializeCalendar(TimeZone* adoptZone, const Locale& locale, UErrorCode& status);

/**
     * initializes fSymbols from parameters.
     * @param locale Locale of the symbols
     * @param calendar Alias to Calendar that will be used.
     * @param status Error code
     */
    void initializeSymbols(const Locale& locale, Calendar* calendar, UErrorCode& status);

/**
     * Called by several of the constructors to load pattern data and formatting symbols
     * out of a resource bundle and initialize the locale based on it.
     * @param timeStyle     The time style, as passed to DateFormat::createDateInstance().
     * @param dateStyle     The date style, as passed to DateFormat::createTimeInstance().
     * @param locale        The locale to load the patterns from.
     * @param status        Filled in with an error code if loading the data from the
     *                      resources fails.
     */
    void construct(EStyle timeStyle, EStyle dateStyle, const Locale& locale, UErrorCode& status);

/**
     * Called by construct() and the various constructors to set up the SimpleDateFormat's
     * Calendar and NumberFormat objects.
     * @param locale    The locale for which we want a Calendar and a NumberFormat.
     * @param status    Filled in with an error code if creating either subobject fails.
     */
    void initialize(const Locale& locale, UErrorCode& status);

/**
 * Private code-size reduction function used by subParse.
 * @param text the time text being parsed.
 * @param start where to start parsing.
 * @param field the date field being parsed.
 * @param stringArray the string array to parsed.
 * @param stringArrayCount the size of the array.
 * @param cal a Calendar set to the date and time to be formatted
 * into a date/time string.
 * @return the new start position if matching succeeded; a negative number
 * indicating matching failure, otherwise.
 */
 int32_t matchQuarterString(const UnicodeString& text, int32_t start, UCalendarDateFields field,
 const UnicodeString* stringArray, int32_t stringArrayCount, Calendar& cal) const;
 
 /**
 * Private function used by subParse to match literal pattern text.
 *
 * @param pattern the pattern string
 * @param patternOffset the starting offset into the pattern text. On
 * outupt will be set the offset of the first non-literal character in the pattern
 * @param text the text being parsed
 * @param textOffset the starting offset into the text. On output
 * will be set to the offset of the character after the match
 * @param lenient <code>TRUE</code> if the parse is lenient, <code>FALSE</code> otherwise.
 *
 * @return <code>TRUE</code> if the literal text could be matched, <code>FALSE</code> otherwise.
 */
 static UBool matchLiterals(const UnicodeString &pattern, int32_t &patternOffset,
 const UnicodeString &text, int32_t &textOffset, UBool lenient);
 
 /**
 * Private member function that converts the parsed date strings into
 * timeFields. Returns -start (for ParsePosition) if failed.
 * @param text the time text to be parsed.
 * @param start where to start parsing.
 * @param ch the pattern character for the date field text to be parsed.
 * @param count the count of a pattern character.
 * @param obeyCount if true then the count is strictly obeyed.
 * @param allowNegative
 * @param ambiguousYear If true then the two-digit year == the default start year.
 * @param saveHebrewMonth Used to hang onto month until year is known.
 * @param cal a Calendar set to the date and time to be formatted
 * into a date/time string.
 * @param patLoc
 * @param numericLeapMonthFormatter If non-null, used to parse numeric leap months.
 * @return the new start position if matching succeeded; a negative number
 * indicating matching failure, otherwise.
 */
 int32_t subParse(const UnicodeString& text, int32_t& start, UChar ch, int32_t count,
 UBool obeyCount, UBool allowNegative, UBool ambiguousYear[], int32_t& saveHebrewMonth, Calendar& cal,
 int32_t patLoc, MessageFormat * numericLeapMonthFormatter) const;

void parseInt(const UnicodeString& text,
                  Formattable& number,
                  ParsePosition& pos,
                  UBool allowNegative,
                  NumberFormat *fmt) const;

void parseInt(const UnicodeString& text,
                  Formattable& number,
                  int32_t maxDigits,
                  ParsePosition& pos,
                  UBool allowNegative,
                  NumberFormat *fmt) const;

int32_t checkIntSuffix(const UnicodeString& text, int32_t start,
                           int32_t patLoc, UBool isNegative) const;

/**
     * Translate a pattern, mapping each character in the from string to the
     * corresponding character in the to string. Return an error if the original
     * pattern contains an unmapped character, or if a quote is unmatched.
     * Quoted (single quotes only) material is not translated.
     * @param originalPattern   the original pattern.
     * @param translatedPattern Output param to receive the translited pattern.
     * @param from              the characters to be translited from.
     * @param to                the characters to be translited to.
     * @param status            Receives a status code, which will be U_ZERO_ERROR
     *                          if the operation succeeds.
     */
    static void translatePattern(const UnicodeString& originalPattern,
                                UnicodeString& translatedPattern,
                                const UnicodeString& from,
                                const UnicodeString& to,
                                UErrorCode& status);

/**
     * Sets the starting date of the 100-year window that dates with 2-digit years
     * are considered to fall within.
     * @param startDate the start date
     * @param status    Receives a status code, which will be U_ZERO_ERROR
     *                  if the operation succeeds.
     */
    void         parseAmbiguousDatesAsAfter(UDate startDate, UErrorCode& status);

/**
     * Return the length matched by the given affix, or -1 if none.
     * Runs of white space in the affix, match runs of white space in
     * the input.
     * @param affix pattern string, taken as a literal
     * @param input input text
     * @param pos offset into input at which to begin matching
     * @return length of input that matches, or -1 if match failure
     */
    int32_t compareSimpleAffix(const UnicodeString& affix,
                   const UnicodeString& input,
                   int32_t pos) const;

/**
     * Skip over a run of zero or more Pattern_White_Space characters at
     * pos in text.
     */
    int32_t skipPatternWhiteSpace(const UnicodeString& text, int32_t pos) const;

/**
     * Skip over a run of zero or more isUWhiteSpace() characters at pos
     * in text.
     */
    int32_t skipUWhiteSpace(const UnicodeString& text, int32_t pos) const;

/**
     * Initialize NumberFormat instances used for numbering system overrides.
     */
    void initNumberFormatters(const Locale &locale,UErrorCode &status);

/**
     * Get the numbering system to be used for a particular field.
     */
     NumberFormat * getNumberFormatByIndex(UDateFormatField index) const;

/**
     * Parse the given override string and set up structures for number formats
     */
    void processOverrideString(const Locale &locale, const UnicodeString &str, int8_t type, UErrorCode &status);

/**
     * Used to map pattern characters to Calendar field identifiers.
     */
    static const UCalendarDateFields fgPatternIndexToCalendarField[];

/**
     * Map index into pattern character string to DateFormat field number
     */
    static const UDateFormatField fgPatternIndexToDateFormatField[];

/**
     * Lazy TimeZoneFormat instantiation, semantically const
     */
    TimeZoneFormat *tzFormat() const;

/**
     * Used to map Calendar field to field level.
     * The larger the level, the smaller the field unit.
     * For example, UCAL_ERA level is 0, UCAL_YEAR level is 10,
     * UCAL_MONTH level is 20.
     */
    static const int32_t fgCalendarFieldToLevel[];
    static const int32_t fgPatternCharToLevel[];

/**
     * The formatting pattern for this formatter.
     */
    UnicodeString       fPattern;

/**
     * The numbering system override for dates.
     */
    UnicodeString       fDateOverride;

/**
     * The numbering system override for times.
     */
    UnicodeString       fTimeOverride;

/**
     * The original locale used (for reloading symbols)
     */
    Locale              fLocale;

/**
     * A pointer to an object containing the strings to use in formatting (e.g.,
     * month and day names, AM and PM strings, time zone names, etc.)
     */
    DateFormatSymbols*  fSymbols;   // Owned

/**
     * The time zone formatter
     */
    TimeZoneFormat* fTimeZoneFormat;

/**
     * If dates have ambiguous years, we map them into the century starting
     * at defaultCenturyStart, which may be any date.  If defaultCenturyStart is
     * set to SYSTEM_DEFAULT_CENTURY, which it is by default, then the system
     * values are used.  The instance values defaultCenturyStart and
     * defaultCenturyStartYear are only used if explicitly set by the user
     * through the API method parseAmbiguousDatesAsAfter().
     */
    UDate                fDefaultCenturyStart;

/**
     * See documentation for defaultCenturyStart.
     */
    /*transient*/ int32_t   fDefaultCenturyStartYear;

int32_t tztype; // here to avoid api change

typedef struct NSOverride {
        NumberFormat *nf;
        int32_t hash;
        NSOverride *next;
    } NSOverride;

NumberFormat    **fNumberFormatters;

NSOverride      *fOverrideList;

UBool fHaveDefaultCentury;

UDisplayContext fCapitalizationContext;
};

inline UDate
SimpleDateFormat::get2DigitYearStart(UErrorCode& /*status*/) const
{
    return fDefaultCenturyStart;
}

inline UnicodeString&
SimpleDateFormat::format(const Formattable& obj,
                         UnicodeString& appendTo,
                         UErrorCode& status) const {
    // Don't use Format:: - use immediate base class only,
    // in case immediate base modifies behavior later.
    return DateFormat::format(obj, appendTo, status);
}

inline UnicodeString&
SimpleDateFormat::format(const Formattable& obj,
                         UnicodeString& appendTo,
                         FieldPosition& pos,
                         UErrorCode& status) const
{
    // Don't use Format:: - use immediate base class only,
    // in case immediate base modifies behavior later.
    return DateFormat::format(obj, appendTo, pos, status);
}

inline UnicodeString&
SimpleDateFormat::format(const Formattable& obj,
                         UnicodeString& appendTo,
                         FieldPositionIterator* posIter,
                         UErrorCode& status) const
{
    // Don't use Format:: - use immediate base class only,
    // in case immediate base modifies behavior later.
    return DateFormat::format(obj, appendTo, posIter, status);
}

inline UnicodeString&
SimpleDateFormat::format(UDate date,
                         UnicodeString& appendTo,
                         FieldPosition& fieldPosition) const {
    // Don't use Format:: - use immediate base class only,
    // in case immediate base modifies behavior later.
    return DateFormat::format(date, appendTo, fieldPosition);
}

inline UnicodeString&
SimpleDateFormat::format(UDate date,
                         UnicodeString& appendTo,
                         FieldPositionIterator* posIter,
                         UErrorCode& status) const {
    // Don't use Format:: - use immediate base class only,
    // in case immediate base modifies behavior later.
    return DateFormat::format(date, appendTo, posIter, status);
}

inline UnicodeString&
SimpleDateFormat::format(UDate date, UnicodeString& appendTo) const {
    return DateFormat::format(date, appendTo);
}

U_NAMESPACE_END

#endif /* #if !UCONFIG_NO_FORMATTING */

#endif // _SMPDTFMT
//eof