gecko-dev/modules/libnls/headers/datefmt.h
1998-05-27 02:02:27 +00:00

497 lines
19 KiB
C++

/*
********************************************************************************
* *
* COPYRIGHT: *
* (C) Copyright Taligent, Inc., 1997 *
* (C) Copyright International Business Machines Corporation, 1997 *
* Licensed Material - Program-Property of IBM - All Rights Reserved. *
* US Government Users Restricted Rights - Use, duplication, or disclosure *
* restricted by GSA ADP Schedule Contract with IBM Corp. *
* *
********************************************************************************
*
* File DATEFMT.H
*
* Modification History:
*
* Date Name Description
* 02/19/97 aliu Converted from java.
* 04/01/97 aliu Added support for centuries.
********************************************************************************
*/
#ifndef _DATEFMT
#define _DATEFMT
#include "ptypes.h"
#include "calendar.h"
#include "numfmt.h"
#include "format.h"
#include "locid.h"
class TimeZone;
/**
* DateFormat is an abstract class for a family of classes that convert dates and
* times from their internal representations to textual form and back again in a
* language-independent manner. Converting from the internal representation (milliseconds
* since midnight, January 1, 1970) to text is known as "formatting," and converting
* from text to millis is known as "parsing." We currently define only one concrete
* subclass of DateFormat: SimpleDateFormat, which can handle pretty much all normal
* date formatting and parsing actions.
* <P>
* DateFormat helps you to format and parse dates for any locale. Your code can
* be completely independent of the locale conventions for months, days of the
* week, or even the calendar format: lunar vs. solar.
* <P>
* To format a date for the current Locale, use one of the static factory
* methods:
* <pre>
* . UnicodeString myString;
* . DateFormat* df(DateFormat::createDateInstance());
* . df->format(myDate, myString);
* . delete df;
* </pre>
* If you are formatting multiple numbers, it is more efficient to get the
* format and use it multiple times so that the system doesn't have to fetch the
* information about the local language and country conventions multiple times.
* <pre>
* . Date a[a_length];
* . UnicodeString myString;
* . DateFormat* df(DateFormat::createDateInstance());
* . for (int i = 0; i &lt; a_length; ++i) {
* . cout &lt;&lt; df->format(myDate[i], myString) &lt;&lt; "; ";
* . }
* . delete df;
* </pre>
* To format a date for a different Locale, specify it in the call to
* getDateInstance().
* <pre>
* . DateFormat* df(DateFormat::getDateInstance(Locale.FRANCE));
* </pre>
* You can use a DateFormat to parse also.
* <pre>
* . ErrorCode status = ZERO_ERROR;
* . Formattable* myDate = df.parse(myString, status);
* </pre>
* Use createDateInstance() to produce the normal date format for that country.
* There are other static factory methods available. Use createTimeInstance()
* to produce the normal time format for that country. Use createDateTimeInstance()
* to produce a DateFormat that formats both date and time. You can pass in
* different options to these factory methods to control the length of the
* result; from SHORT to MEDIUM to LONG to FULL. The exact result depends on the
* locale, but generally:
* <ul type=round>
* <li> SHORT is completely numeric, such as 12/13/52 or 3:30pm
* <li> MEDIUM is longer, such as Jan 12, 1952
* <li> LONG is longer, such as January 12, 1952 or 3:30:32pm
* <li> FULL is pretty completely specified, such as
* Tuesday, April 12, 1952 AD or 3:30:42pm PST.
* </ul>
* You can also set the time zone on the format if you wish. If you want even
* more control over the format or parsing, (or want to give your users more
* control), you can try casting the DateFormat you get from the factory methods
* to a SimpleDateFormat. This will work for the majority of countries; just
* remember to chck getDynamicClassID() before carrying out the cast.
* <P>
* You can also use forms of the parse and format methods with ParsePosition and
* FieldPosition to allow you to
* <ul type=round>
* <li> Progressively parse through pieces of a string.
* <li> Align any particular field, or find out where it is for selection
* on the screen.
* </ul>
*/
#ifdef NLS_MAC
#pragma export on
#endif
class T_FORMAT_API DateFormat : public Format {
public:
/**
* The following enum values are used in FieldPosition with date/time formatting.
* They are also used to index into DateFormatSymbols::fgPatternChars, which
* is the list of standard internal-representation pattern characters, and
* the resource bundle localPatternChars data. For this reason, this enum
* should be treated with care; don't change the order or contents of it
* unless you really know what you are doing. You'll probably have to change
* the code in DateFormatSymbols, SimpleDateFormat, and all the locale
* resource bundle data files.
*/
enum EField
{
ERA_FIELD, // ERA field alignment.
YEAR_FIELD, // YEAR field alignment.
MONTH_FIELD, // MONTH field alignment.
DATE_FIELD, // DATE field alignment.
HOUR_OF_DAY1_FIELD, // One-based HOUR_OF_DAY field alignment.
// HOUR_OF_DAY1_FIELD is used for the one-based 24-hour clock.
// For example, 23:59 + 01:00 results in 24:59.
HOUR_OF_DAY0_FIELD, // Zero-based HOUR_OF_DAY field alignment.
// HOUR_OF_DAY0_FIELD is used for the zero-based 24-hour clock.
// For example, 23:59 + 01:00 results in 00:59.
MINUTE_FIELD, // MINUTE field alignment.
SECOND_FIELD, // SECOND field alignment.
MILLISECOND_FIELD, // MILLISECOND field alignment.
DAY_OF_WEEK_FIELD, // DAY_OF_WEEK field alignment.
DAY_OF_YEAR_FIELD, // DAY_OF_YEAR field alignment.
DAY_OF_WEEK_IN_MONTH_FIELD,// DAY_OF_WEEK_IN_MONTH field alignment.
WEEK_OF_YEAR_FIELD, // WEEK_OF_YEAR field alignment.
WEEK_OF_MONTH_FIELD,// WEEK_OF_MONTH field alignment.
AM_PM_FIELD, // AM_PM field alignment.
HOUR1_FIELD, // One-based HOUR field alignment.
// HOUR1_FIELD is used for the one-based 12-hour clock.
// For example, 11:30 PM + 1 hour results in 12:30 AM.
HOUR0_FIELD, // Zero-based HOUR field alignment.
// HOUR0_FIELD is used for the zero-based 12-hour clock.
// For example, 11:30 PM + 1 hour results in 00:30 AM.
TIMEZONE_FIELD // TIMEZONE field alignment.
};
/**
* Constants for various style patterns. These reflect the order of items in
* the DateTimePatterns resource. There are 4 time patterns, 4 date patterns,
* and then the date-time pattern. Each block of 4 values in the resource occurs
* in the order full, long, medium, short.
*/
enum EStyle
{
FULL,
LONGG,
MEDIUM,
SHORT,
DEFAULT = MEDIUM,
DATE_OFFSET = 4,
NONE = -1,
DATE_TIME = 8
};
typedef enum EStyle EStyle;
/**
* Destructor.
*/
virtual ~DateFormat();
/**
* Equality operator. Returns true if the two formats have the same behavior.
*/
virtual t_bool operator==(const Format&) const;
/**
* Format an object to produce a string. This method handles Formattable
* objects with a Date type. If a the Formattable object type is not a Date,
* then it returns a failing ErrorCode.
*
* @param obj The object to format. Must be a Date.
* @param toAppendTo The result of the formatting operation is appended to
* this string.
* @param pos On input: an alignment field, if desired.
* On output: the offsets of the alignment field.
* @param status Output param filled with success/failure status.
* @return The value passed in as toAppendTo (this allows chaining,
* as with UnicodeString::append())
*/
virtual UnicodeString& format(const Formattable& obj,
UnicodeString& toAppendTo,
FieldPosition& pos,
ErrorCode& status) const;
/**
* Formats a Date into a date/time string. This is an abstract method which
* concrete subclasses must implement.
* <P>
* On input, the FieldPosition parameter may have its "field" member filled with
* an enum value specifying a field. On output, the FieldPosition will be filled
* in with the text offsets for that field.
* <P> For example, given a time text
* "1996.07.10 AD at 15:08:56 PDT", if the given fieldPosition.field is
* DateFormat::YEAR_FIELD, the offsets fieldPosition.beginIndex and
* statfieldPositionus.getEndIndex will be set to 0 and 4, respectively.
* <P> Notice
* that if the same time field appears more than once in a pattern, the status will
* be set for the first occurence of that time field. For instance,
* formatting a Date to the time string "1 PM PDT (Pacific Daylight Time)"
* using the pattern "h a z (zzzz)" and the alignment field
* DateFormat::TIMEZONE_FIELD, the offsets fieldPosition.beginIndex and
* fieldPosition.getEndIndex will be set to 5 and 8, respectively, for the first
* occurence of the timezone pattern character 'z'.
*
* @param date a Date to be formatted into a date/time string.
* @param toAppendTo the result of the formatting operation is appended to
* the end of this string.
* @param fieldPosition On input: an alignment field, if desired (see examples above)
* On output: the offsets of the alignment field (see examples above)
* @return A reference to 'toAppendTo'.
*/
virtual UnicodeString& format( Date date,
UnicodeString& toAppendTo,
FieldPosition& fieldPosition) const = 0;
/**
* Formats a Date into a date/time string. If there is a problem, you won't
* know, using this method. Use the overloaded format() method which takes a
* FieldPosition& to detect formatting problems.
*
* @param date The Date value to be formatted into a string.
* @param result Output param which will receive the formatted date.
* @return A reference to 'result'.
*/
UnicodeString& format(Date date, UnicodeString& result) const;
/**
* Parse a date/time string.
*
* @param text The string to be parsed into a Date value.
* @param status Output param to be set to success/failure code. If
* 'text' cannot be parsed, it will be set to a failure
* code.
* @result The parsed Date value, if successful.
*/
virtual Date parse( const UnicodeString& text,
ErrorCode& status) 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).
* <P>
* 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 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 Date if the input could be parsed.
*/
virtual Date parse( const UnicodeString& text,
ParsePosition& pos) const = 0;
/**
* Parse a string to produce an object. This methods handles parsing of
* date/time strings into Formattable objects with Date types.
* <P>
* Before calling, set parse_pos.index to the offset you want to start
* parsing at in the source. After calling, parse_pos.index is the end of
* the text you parsed. If error occurs, index is unchanged.
* <P>
* When parsing, leading whitespace is discarded (with a successful parse),
* while trailing whitespace is left as is.
* <P>
* See Format::parseObject() for more.
*
* @param source The string to be parsed into an object.
* @param result Formattable to be set to the parse result.
* If parse fails, return contents are undefined.
* @param parse_pos The position to start parsing at. Upon return
* this param is set to the position after the
* last character successfully parsed. If the
* source is not parsed successfully, this param
* will remain unchanged.
* @return A newly created Formattable* object, or NULL
* on failure. The caller owns this and should
* delete it when done.
*/
virtual void parseObject(const UnicodeString& source,
Formattable& result,
ParsePosition& parse_pos) const;
/**
* Create a default date/time formatter that uses the SHORT style for both
* the date and the time.
*
* @return A date/time formatter which the caller owns.
*/
static DateFormat* createInstance();
/**
* Creates a time formatter with the given formatting style for the given
* locale.
*
* @param style The given formatting style. For example,
* SHORT for "h:mm a" in the US locale.
* @param aLocale The given locale.
* @return A time formatter which the caller owns.
*/
static DateFormat* createTimeInstance(EStyle style = DEFAULT,
const Locale& aLocale = Locale::getDefault());
/**
* Creates a date formatter with the given formatting style for the given
* const locale.
*
* @param style The given formatting style. For example,
* SHORT for "M/d/yy" in the US locale.
* @param aLocale The given locale.
* @return A date formatter which the caller owns.
*/
static DateFormat* createDateInstance(EStyle style = DEFAULT,
const Locale& aLocale = Locale::getDefault());
/**
* Creates a date/time formatter with the given formatting styles for the
* given locale.
*
* @param dateStyle The given formatting style for the date portion of the result.
* For example, SHORT for "M/d/yy" in the US locale.
* @param timeStyle The given formatting style for the time portion of the result.
* For example, SHORT for "h:mm a" in the US locale.
* @param aLocale The given locale.
* @return A date/time formatter which the caller owns.
*/
static DateFormat* createDateTimeInstance(EStyle dateStyle = DEFAULT,
EStyle timeStyle = DEFAULT,
const Locale& aLocale = Locale::getDefault());
/**
* Gets the set of locales for which DateFormats are installed.
* @param count Filled in with the number of locales in the list that is returned.
* @return the set of locales for which DateFormats are installed. The caller
* does NOT own this list and must not delete it.
*/
static const Locale* getAvailableLocales(t_int32& count);
/**
* Returns true if the formatter is set for lenient parsing.
*/
virtual t_bool isLenient() const;
/**
* Specify whether or not date/time parsing is to be lenient. With lenient
* parsing, the parser may use heuristics to interpret inputs that do not
* precisely match this object's format. With strict parsing, inputs must
* match this object's format.
* @see Calendar::setLenient
*/
virtual void setLenient(t_bool lenient);
/**
* Gets the calendar associated with this date/time formatter.
* @return the calendar associated with this date/time formatter.
*/
virtual const Calendar* getCalendar() 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.
*/
virtual void adoptCalendar(Calendar* calendarToAdopt);
/**
* Set the calendar to be used by this date format. Initially, the default
* calendar for the specified or default locale is used.
*/
virtual void setCalendar(const Calendar& newCalendar);
/**
* Gets the number formatter which this date/time formatter uses to format
* and parse the numeric portions of the pattern.
* @return the number formatter which this date/time formatter uses.
*/
virtual const NumberFormat* getNumberFormat() const;
/**
* Allows you to set the number formatter. The caller should
* not delete the NumberFormat object after it is adopted by this call.
* @param formatToAdopt NumberFormat object to be adopted.
*/
virtual void adoptNumberFormat(NumberFormat* formatToAdopt);
/**
* Allows you to set the number formatter.
* @param formatToAdopt NumberFormat object to be adopted.
*/
virtual void setNumberFormat(const NumberFormat& newNumberFormat);
/**
* Returns a reference to the TimeZone used by this DateFormat's calendar.
* @return the time zone associated with the calendar of DateFormat.
*/
virtual const TimeZone& getTimeZone() const;
/**
* Sets the time zone for the calendar of this DateFormat object. The caller
* no longer owns the TimeZone object and should not delete it after this call.
* @param zone the new time zone.
*/
virtual void adoptTimeZone(TimeZone* zoneToAdopt);
/**
* Sets the time zone for the calendar of this DateFormat object.
* @param zone the new time zone.
*/
virtual void setTimeZone(const TimeZone& zone);
protected:
/**
* Default constructor. Creates a DateFormat with no Calendar or NumberFormat
* associated with it. This constructor depends on the subclasses to fill in
* the calendar and numberFormat fields.
*/
DateFormat();
/**
* Copy constructor.
*/
DateFormat(const DateFormat&);
/**
* Default assignment operator.
*/
DateFormat& operator=(const DateFormat&);
/**
* The calendar that DateFormat uses to produce the time field values needed
* to implement date/time formatting. Subclasses should generally initialize
* this to the default calendar for the locale associated with this DateFormat.
*/
Calendar* fCalendar;
/**
* The number formatter that DateFormat uses to format numbers in dates and
* times. Subclasses should generally initialize this to the default number
* format for the locale associated with this DateFormat.
*/
NumberFormat* fNumberFormat;
private:
/**
* Gets the date/time formatter with the given formatting styles for the
* given locale.
* @param dateStyle the given date formatting style.
* @param timeStyle the given time formatting style.
* @param inLocale the given locale.
* @return a date/time formatter, or 0 on failure.
*/
static DateFormat* create(EStyle timeStyle, EStyle dateStyle, const Locale&);
/**
* fgLocales and fgLocalesCount cache the available locales array that is returned
* by getAvailableLocales().
*/
static t_int32 fgLocalesCount;
/**
* fgLocales and fgLocalesCount cache the available locales array that is returned
* by getAvailableLocales().
*/
static const Locale* fgLocales;
};
#ifdef NLS_MAC
#pragma export off
#endif
#endif // _DATEFMT
//eof