* This API is very basic and is intended to be a building block for more * fancy APIs. The caller tells it exactly what to display in a locale * independent way. While this class automatically provides the correct plural * forms, the grammatical form is otherwise as neutral as possible. It is the * caller's responsibility to handle cut-off logic such as deciding between * displaying "in 7 days" or "in 1 week." This API supports relative dates * involving one single unit. This API does not support relative dates * involving compound units, * e.g "in 5 days and 4 hours" nor does it support parsing. *
* This class is mostly thread safe and immutable with the following caveats: * 1. The assignment operator violates Immutability. It must not be used * concurrently with other operations. * 2. Caller must not hold onto adopted pointers. *
* This class is not intended for public subclassing. *
* Here are some examples of use: *
*** UErrorCode status = U_ZERO_ERROR; * UnicodeString appendTo; * RelativeDateTimeFormatter fmt(status); * // Appends "in 1 day" * fmt.format( * 1, UDAT_DIRECTION_NEXT, UDAT_RELATIVE_DAYS, appendTo, status); * // Appends "in 3 days" * fmt.format( * 3, UDAT_DIRECTION_NEXT, UDAT_RELATIVE_DAYS, appendTo, status); * // Appends "3.2 years ago" * fmt.format( * 3.2, UDAT_DIRECTION_LAST, UDAT_RELATIVE_YEARS, appendTo, status); * // Appends "last Sunday" * fmt.format(UDAT_DIRECTION_LAST, UDAT_ABSOLUTE_SUNDAY, appendTo, status); * // Appends "this Sunday" * fmt.format(UDAT_DIRECTION_THIS, UDAT_ABSOLUTE_SUNDAY, appendTo, status); * // Appends "next Sunday" * fmt.format(UDAT_DIRECTION_NEXT, UDAT_ABSOLUTE_SUNDAY, appendTo, status); * // Appends "Sunday" * fmt.format(UDAT_DIRECTION_PLAIN, UDAT_ABSOLUTE_SUNDAY, appendTo, status); * * // Appends "yesterday" * fmt.format(UDAT_DIRECTION_LAST, UDAT_ABSOLUTE_DAY, appendTo, status); * // Appends "today" * fmt.format(UDAT_DIRECTION_THIS, UDAT_ABSOLUTE_DAY, appendTo, status); * // Appends "tomorrow" * fmt.format(UDAT_DIRECTION_NEXT, UDAT_ABSOLUTE_DAY, appendTo, status); * // Appends "now" * fmt.format(UDAT_DIRECTION_PLAIN, UDAT_ABSOLUTE_NOW, appendTo, status); * **
* In the future, we may add more forms, such as abbreviated/short forms
* (3 secs ago), and relative day periods ("yesterday afternoon"), etc.
*
* The RelativeDateTimeFormatter class is not intended for public subclassing.
*
* @stable ICU 53
*/
class U_I18N_API RelativeDateTimeFormatter : public UObject {
public:
/**
* Create RelativeDateTimeFormatter with default locale.
* @stable ICU 53
*/
RelativeDateTimeFormatter(UErrorCode& status);
/**
* Create RelativeDateTimeFormatter with given locale.
* @stable ICU 53
*/
RelativeDateTimeFormatter(const Locale& locale, UErrorCode& status);
/**
* Create RelativeDateTimeFormatter with given locale and NumberFormat.
*
* @param locale the locale
* @param nfToAdopt Constructed object takes ownership of this pointer.
* It is an error for caller to delete this pointer or change its
* contents after calling this constructor.
* @param status Any error is returned here.
* @stable ICU 53
*/
RelativeDateTimeFormatter(
const Locale& locale, NumberFormat *nfToAdopt, UErrorCode& status);
/**
* Create RelativeDateTimeFormatter with given locale, NumberFormat,
* and capitalization context.
*
* @param locale the locale
* @param nfToAdopt Constructed object takes ownership of this pointer.
* It is an error for caller to delete this pointer or change its
* contents after calling this constructor. Caller may pass NULL for
* this argument if they want default number format behavior.
* @param style the format style. The UDAT_RELATIVE bit field has no effect.
* @param capitalizationContext A value from UDisplayContext that pertains to
* capitalization.
* @param status Any error is returned here.
* @stable ICU 54
*/
RelativeDateTimeFormatter(
const Locale& locale,
NumberFormat *nfToAdopt,
UDateRelativeDateTimeFormatterStyle style,
UDisplayContext capitalizationContext,
UErrorCode& status);
/**
* Copy constructor.
* @stable ICU 53
*/
RelativeDateTimeFormatter(const RelativeDateTimeFormatter& other);
/**
* Assignment operator.
* @stable ICU 53
*/
RelativeDateTimeFormatter& operator=(
const RelativeDateTimeFormatter& other);
/**
* Destructor.
* @stable ICU 53
*/
virtual ~RelativeDateTimeFormatter();
/**
* Formats a relative date with a quantity such as "in 5 days" or
* "3 months ago"
*
* This method returns a String. To get more information about the
* formatting result, use formatToValue().
*
* @param quantity The numerical amount e.g 5. This value is formatted
* according to this object's NumberFormat object.
* @param direction NEXT means a future relative date; LAST means a past
* relative date. If direction is anything else, this method sets
* status to U_ILLEGAL_ARGUMENT_ERROR.
* @param unit the unit e.g day? month? year?
* @param appendTo The string to which the formatted result will be
* appended
* @param status ICU error code returned here.
* @return appendTo
* @stable ICU 53
*/
UnicodeString& format(
double quantity,
UDateDirection direction,
UDateRelativeUnit unit,
UnicodeString& appendTo,
UErrorCode& status) const;
#ifndef U_HIDE_DRAFT_API
/**
* Formats a relative date with a quantity such as "in 5 days" or
* "3 months ago"
*
* This method returns a FormattedRelativeDateTime, which exposes more
* information than the String returned by format().
*
* @param quantity The numerical amount e.g 5. This value is formatted
* according to this object's NumberFormat object.
* @param direction NEXT means a future relative date; LAST means a past
* relative date. If direction is anything else, this method sets
* status to U_ILLEGAL_ARGUMENT_ERROR.
* @param unit the unit e.g day? month? year?
* @param status ICU error code returned here.
* @return The formatted relative datetime
* @draft ICU 64
*/
FormattedRelativeDateTime formatToValue(
double quantity,
UDateDirection direction,
UDateRelativeUnit unit,
UErrorCode& status) const;
#endif /* U_HIDE_DRAFT_API */
/**
* Formats a relative date without a quantity.
*
* This method returns a String. To get more information about the
* formatting result, use formatToValue().
*
* @param direction NEXT, LAST, THIS, etc.
* @param unit e.g SATURDAY, DAY, MONTH
* @param appendTo The string to which the formatted result will be
* appended. If the value of direction is documented as not being fully
* supported in all locales then this method leaves appendTo unchanged if
* no format string is available.
* @param status ICU error code returned here.
* @return appendTo
* @stable ICU 53
*/
UnicodeString& format(
UDateDirection direction,
UDateAbsoluteUnit unit,
UnicodeString& appendTo,
UErrorCode& status) const;
#ifndef U_HIDE_DRAFT_API
/**
* Formats a relative date without a quantity.
*
* This method returns a FormattedRelativeDateTime, which exposes more
* information than the String returned by format().
*
* If the string is not available in the requested locale, the return
* value will be empty (calling toString will give an empty string).
*
* @param direction NEXT, LAST, THIS, etc.
* @param unit e.g SATURDAY, DAY, MONTH
* @param status ICU error code returned here.
* @return The formatted relative datetime
* @draft ICU 64
*/
FormattedRelativeDateTime formatToValue(
UDateDirection direction,
UDateAbsoluteUnit unit,
UErrorCode& status) const;
#endif /* U_HIDE_DRAFT_API */
/**
* Format a combination of URelativeDateTimeUnit and numeric offset
* using a numeric style, e.g. "1 week ago", "in 1 week",
* "5 weeks ago", "in 5 weeks".
*
* This method returns a String. To get more information about the
* formatting result, use formatNumericToValue().
*
* @param offset The signed offset for the specified unit. This
* will be formatted according to this object's
* NumberFormat object.
* @param unit The unit to use when formatting the relative
* date, e.g. UDAT_REL_UNIT_WEEK,
* UDAT_REL_UNIT_FRIDAY.
* @param appendTo The string to which the formatted result will be
* appended.
* @param status ICU error code returned here.
* @return appendTo
* @stable ICU 57
*/
UnicodeString& formatNumeric(
double offset,
URelativeDateTimeUnit unit,
UnicodeString& appendTo,
UErrorCode& status) const;
#ifndef U_HIDE_DRAFT_API
/**
* Format a combination of URelativeDateTimeUnit and numeric offset
* using a numeric style, e.g. "1 week ago", "in 1 week",
* "5 weeks ago", "in 5 weeks".
*
* This method returns a FormattedRelativeDateTime, which exposes more
* information than the String returned by formatNumeric().
*
* @param offset The signed offset for the specified unit. This
* will be formatted according to this object's
* NumberFormat object.
* @param unit The unit to use when formatting the relative
* date, e.g. UDAT_REL_UNIT_WEEK,
* UDAT_REL_UNIT_FRIDAY.
* @param status ICU error code returned here.
* @return The formatted relative datetime
* @draft ICU 64
*/
FormattedRelativeDateTime formatNumericToValue(
double offset,
URelativeDateTimeUnit unit,
UErrorCode& status) const;
#endif /* U_HIDE_DRAFT_API */
/**
* Format a combination of URelativeDateTimeUnit and numeric offset
* using a text style if possible, e.g. "last week", "this week",
* "next week", "yesterday", "tomorrow". Falls back to numeric
* style if no appropriate text term is available for the specified
* offset in the object's locale.
*
* This method returns a String. To get more information about the
* formatting result, use formatToValue().
*
* @param offset The signed offset for the specified unit.
* @param unit The unit to use when formatting the relative
* date, e.g. UDAT_REL_UNIT_WEEK,
* UDAT_REL_UNIT_FRIDAY.
* @param appendTo The string to which the formatted result will be
* appended.
* @param status ICU error code returned here.
* @return appendTo
* @stable ICU 57
*/
UnicodeString& format(
double offset,
URelativeDateTimeUnit unit,
UnicodeString& appendTo,
UErrorCode& status) const;
#ifndef U_HIDE_DRAFT_API
/**
* Format a combination of URelativeDateTimeUnit and numeric offset
* using a text style if possible, e.g. "last week", "this week",
* "next week", "yesterday", "tomorrow". Falls back to numeric
* style if no appropriate text term is available for the specified
* offset in the object's locale.
*
* This method returns a FormattedRelativeDateTime, which exposes more
* information than the String returned by format().
*
* @param offset The signed offset for the specified unit.
* @param unit The unit to use when formatting the relative
* date, e.g. UDAT_REL_UNIT_WEEK,
* UDAT_REL_UNIT_FRIDAY.
* @param status ICU error code returned here.
* @return The formatted relative datetime
* @draft ICU 64
*/
FormattedRelativeDateTime formatToValue(
double offset,
URelativeDateTimeUnit unit,
UErrorCode& status) const;
#endif /* U_HIDE_DRAFT_API */
/**
* Combines a relative date string and a time string in this object's
* locale. This is done with the same date-time separator used for the
* default calendar in this locale.
*
* @param relativeDateString the relative date, e.g 'yesterday'
* @param timeString the time e.g '3:45'
* @param appendTo concatenated date and time appended here
* @param status ICU error code returned here.
* @return appendTo
* @stable ICU 53
*/
UnicodeString& combineDateAndTime(
const UnicodeString& relativeDateString,
const UnicodeString& timeString,
UnicodeString& appendTo,
UErrorCode& status) const;
/**
* Returns the NumberFormat this object is using.
*
* @stable ICU 53
*/
const NumberFormat& getNumberFormat() const;
/**
* Returns the capitalization context.
*
* @stable ICU 54
*/
UDisplayContext getCapitalizationContext() const;
/**
* Returns the format style.
*
* @stable ICU 54
*/
UDateRelativeDateTimeFormatterStyle getFormatStyle() const;
private:
const RelativeDateTimeCacheData* fCache;
const SharedNumberFormat *fNumberFormat;
const SharedPluralRules *fPluralRules;
UDateRelativeDateTimeFormatterStyle fStyle;
UDisplayContext fContext;
const SharedBreakIterator *fOptBreakIterator;
Locale fLocale;
void init(
NumberFormat *nfToAdopt,
BreakIterator *brkIter,
UErrorCode &status);
UnicodeString& adjustForContext(UnicodeString &) const;
UBool checkNoAdjustForContext(UErrorCode& status) const;
template