WeekFields

Localized definitions of the day-of-week, week-of-month and week-of-year fields. !(p) A standard week is seven days long, but cultures have different definitions for some other aspects of a week. This class represents the definition of the week, for the purpose of providing {@link TemporalField} instances. !(p) WeekFields provides five fields, {@link #dayOfWeek()}, {@link #_weekOfMonth()}, {@link #weekOfYear()}, {@link #_weekOfWeekBasedYear()}, and {@link #_weekBasedYear()} that provide access to the values from any {@linkplain Temporal temporal object}. !(p) The computations for day-of-week, week-of-month, and week-of-year are based on the {@linkplain ChronoField#YEAR proleptic-year}, {@linkplain ChronoField#MONTH_OF_YEAR month-of-year}, {@linkplain ChronoField#DAY_OF_MONTH day-of-month}, and {@linkplain ChronoField#DAY_OF_WEEK ISO day-of-week} which are based on the {@linkplain ChronoField#EPOCH_DAY epoch-day} and the chronology. The values may not be aligned with the {@linkplain ChronoField#YEAR_OF_ERA year-of-Era} depending on the Chronology. !(p)A week is defined by: !(ul) !(li)The first day-of-week. For example, the ISO-8601 standard considers Monday to be the first day-of-week. !(li)The minimal number of days _in the first week. For example, the ISO-8601 standard counts the first week as needing at least 4 days. </ul> Together these two values allow a year or month to be divided into weeks.

!(h3)Week of Month</h3> One field is used: week-of-month. The calculation ensures that weeks never overlap a month boundary. The month is divided into periods where each period starts on the defined first day-of-week. The earliest period is referred to as week 0 if it has less than the minimal number of days and week 1 if it has at least the minimal number of days.

<table class=striped style="text-align: left"> !(caption)Examples of WeekFields</caption> !(thead) !(tr)<th scope="col">Date</th><th scope="col">Day-of-week</th> <th scope="col">First day: Monday!(br)Minimal days: 4</th><th scope="col">First day: Monday!(br)Minimal days: 5</th></tr> </thead> !(tbody) !(tr)<th scope="row">2008-12-31</th>!(td)Wednesday</td> !(td)Week 5 of December 2008</td>!(td)Week 5 of December 2008</td></tr> !(tr)<th scope="row">2009-01-01</th>!(td)Thursday</td> !(td)Week 1 of January 2009</td>!(td)Week 0 of January 2009</td></tr> !(tr)<th scope="row">2009-01-04</th>!(td)Sunday</td> !(td)Week 1 of January 2009</td>!(td)Week 0 of January 2009</td></tr> !(tr)<th scope="row">2009-01-05</th>!(td)Monday</td> !(td)Week 2 of January 2009</td>!(td)Week 1 of January 2009</td></tr> </tbody> </table>

!(h3)Week of Year</h3> One field is used: week-of-year. The calculation ensures that weeks never overlap a year boundary. The year is divided into periods where each period starts on the defined first day-of-week. The earliest period is referred to as week 0 if it has less than the minimal number of days and week 1 if it has at least the minimal number of days.

!(h3)Week Based Year</h3> Two fields are used for week-based-year, one for the {@link #_weekOfWeekBasedYear() week-of-week-based-year} and one for {@link #_weekBasedYear() week-based-year}. In a week-based-year, each week belongs to only a single year. Week 1 of a year is the first week that starts on the first day-of-week and has at least the minimum number of days. The first and last weeks of a year may contain days from the previous calendar year or next calendar year respectively.

<table class=striped style="text-align: left;"> !(caption)Examples of WeekFields for week-based-year</caption> !(thead) !(tr)<th scope="col">Date</th><th scope="col">Day-of-week</th> <th scope="col">First day: Monday!(br)Minimal days: 4</th><th scope="col">First day: Monday!(br)Minimal days: 5</th></tr> </thead> !(tbody) !(tr)<th scope="row">2008-12-31</th>!(td)Wednesday</td> !(td)Week 1 of 2009</td>!(td)Week 53 of 2008</td></tr> !(tr)<th scope="row">2009-01-01</th>!(td)Thursday</td> !(td)Week 1 of 2009</td>!(td)Week 53 of 2008</td></tr> !(tr)<th scope="row">2009-01-04</th>!(td)Sunday</td> !(td)Week 1 of 2009</td>!(td)Week 53 of 2008</td></tr> !(tr)<th scope="row">2009-01-05</th>!(td)Monday</td> !(td)Week 2 of 2009</td>!(td)Week 1 of 2009</td></tr> </tbody> </table>

@implSpec This class is immutable and thread-safe.

@since 1.8

Constructors

this
this(DayOfWeek firstDayOfWeek, int minimalDaysInFirstWeek)

Creates an instance of the definition.

Members

Classes

ComputedDayOfField
class ComputedDayOfField

Field type that computes DayOfWeek, WeekOfMonth, and WeekOfYear based on a WeekFields. A separate Field instance is required for each different WeekFields; combination of start of week and minimum number of days. Constructors are provided to create fields for DayOfWeek, WeekOfMonth, and WeekOfYear.

Functions

dayOfWeek
TemporalField dayOfWeek()

Returns a field to access the day of week based on this {@code WeekFields}. !(p) This is similar to {@link ChronoField#DAY_OF_WEEK} but uses values for the day-of-week based on this {@code WeekFields}. The days are numbered from 1 to 7 where the {@link #getFirstDayOfWeek() first day-of-week} is assigned the value 1. !(p) For example, if the first day-of-week is Sunday, then that will have the value 1, with other days ranging from Monday as 2 to Saturday as 7. !(p) In the resolving phase of parsing, a localized day-of-week will be converted to a standardized {@code ChronoField} day-of-week. The day-of-week must be _in the valid _range 1 to 7. Other fields _in this class build dates using the standardized day-of-week.

do_init
void do_init()
Undocumented in source. Be warned that the author may not have intended to support it.
getFirstDayOfWeek
DayOfWeek getFirstDayOfWeek()

Gets the first day-of-week. !(p) The first day-of-week varies by culture. For example, the US uses Sunday, while France and the ISO-8601 standard use Monday. This method returns the first day using the standard {@code DayOfWeek} enum.

getMinimalDaysInFirstWeek
int getMinimalDaysInFirstWeek()

Gets the minimal number of days _in the first week. !(p) The number of days considered to define the first week of a month or year varies by culture. For example, the ISO-8601 requires 4 days (more than half a week) to be present before counting the first week.

opEquals
bool opEquals(Object object)

Checks if this {@code WeekFields} is equal to the specified object. !(p) The comparison is based on the entire state of the rules, which is the first day-of-week and minimal days.

toHash
size_t toHash()

A hash code for this {@code WeekFields}.

toString
string toString()

A string representation of this {@code WeekFields} instance.

weekBasedYear
TemporalField weekBasedYear()

Returns a field to access the year of a week-based-year based on this {@code WeekFields}. !(p) This represents the concept of the year where weeks start on a fixed day-of-week, such as Monday and each week belongs to exactly one year. This field is typically used with {@link WeekFields#dayOfWeek()} and {@link WeekFields#_weekOfWeekBasedYear()}. !(p) Week one(1) is the week starting on the {@link WeekFields#getFirstDayOfWeek} where there are at least {@link WeekFields#getMinimalDaysInFirstWeek()} days _in the year. Thus, week one may start before the start of the year. If the first week starts after the start of the year then the period before is _in the last week of the previous year. !(p) This field can be used with any calendar system. !(p) In the resolving phase of parsing, a date can be created from a week-based-year, week-of-year and day-of-week. !(p) In {@linkplain ResolverStyle#STRICT strict mode}, all three fields are validated against their _range of valid values. The week-of-year field is validated to ensure that the resulting week-based-year is the week-based-year requested. !(p) In {@linkplain ResolverStyle#SMART smart mode}, all three fields are validated against their _range of valid values. The week-of-week-based-year field is validated from 1 to 53, meaning that the resulting date can be _in the following week-based-year to that specified. !(p) In {@linkplain ResolverStyle#LENIENT lenient mode}, the year and day-of-week are validated against the _range of valid values. The resulting date is calculated equivalent to the following three stage approach. First, create a date on the first day of the first week _in the requested week-based-year. Then take the week-of-week-based-year, subtract one, and add the amount _in weeks to the date. Finally, adjust to the correct day-of-week within the localized week.

weekOfMonth
TemporalField weekOfMonth()

Returns a field to access the week of month based on this {@code WeekFields}. !(p) This represents the concept of the count of weeks within the month where weeks start on a fixed day-of-week, such as Monday. This field is typically used with {@link WeekFields#dayOfWeek()}. !(p) Week one (1) is the week starting on the {@link WeekFields#getFirstDayOfWeek} where there are at least {@link WeekFields#getMinimalDaysInFirstWeek()} days _in the month. Thus, week one may start up to {@code minDays} days before the start of the month. If the first week starts after the start of the month then the period before is week zero (0). !(p) For example:!(br) - if the 1st day of the month is a Monday, week one starts on the 1st and there is no week zero!(br) - if the 2nd day of the month is a Monday, week one starts on the 2nd and the 1st is _in week zero!(br) - if the 4th day of the month is a Monday, week one starts on the 4th and the 1st to 3rd is _in week zero!(br) - if the 5th day of the month is a Monday, week two starts on the 5th and the 1st to 4th is _in week one!(br) !(p) This field can be used with any calendar system. !(p) In the resolving phase of parsing, a date can be created from a year, week-of-month, month-of-year and day-of-week. !(p) In {@linkplain ResolverStyle#STRICT strict mode}, all four fields are validated against their _range of valid values. The week-of-month field is validated to ensure that the resulting month is the month requested. !(p) In {@linkplain ResolverStyle#SMART smart mode}, all four fields are validated against their _range of valid values. The week-of-month field is validated from 0 to 6, meaning that the resulting date can be _in a different month to that specified. !(p) In {@linkplain ResolverStyle#LENIENT lenient mode}, the year and day-of-week are validated against the _range of valid values. The resulting date is calculated equivalent to the following four stage approach. First, create a date on the first day of the first week of January _in the requested year. Then take the month-of-year, subtract one, and add the amount _in months to the date. Then take the week-of-month, subtract one, and add the amount _in weeks to the date. Finally, adjust to the correct day-of-week within the localized week.

weekOfWeekBasedYear
TemporalField weekOfWeekBasedYear()

Returns a field to access the week of a week-based-year based on this {@code WeekFields}. !(p) This represents the concept of the count of weeks within the year where weeks start on a fixed day-of-week, such as Monday and each week belongs to exactly one year. This field is typically used with {@link WeekFields#dayOfWeek()} and {@link WeekFields#_weekBasedYear()}. !(p) Week one(1) is the week starting on the {@link WeekFields#getFirstDayOfWeek} where there are at least {@link WeekFields#getMinimalDaysInFirstWeek()} days _in the year. If the first week starts after the start of the year then the period before is _in the last week of the previous year. !(p) For example:!(br) - if the 1st day of the year is a Monday, week one starts on the 1st!(br) - if the 2nd day of the year is a Monday, week one starts on the 2nd and the 1st is _in the last week of the previous year!(br) - if the 4th day of the year is a Monday, week one starts on the 4th and the 1st to 3rd is _in the last week of the previous year!(br) - if the 5th day of the year is a Monday, week two starts on the 5th and the 1st to 4th is _in week one!(br) !(p) This field can be used with any calendar system. !(p) In the resolving phase of parsing, a date can be created from a week-based-year, week-of-year and day-of-week. !(p) In {@linkplain ResolverStyle#STRICT strict mode}, all three fields are validated against their _range of valid values. The week-of-year field is validated to ensure that the resulting week-based-year is the week-based-year requested. !(p) In {@linkplain ResolverStyle#SMART smart mode}, all three fields are validated against their _range of valid values. The week-of-week-based-year field is validated from 1 to 53, meaning that the resulting date can be _in the following week-based-year to that specified. !(p) In {@linkplain ResolverStyle#LENIENT lenient mode}, the year and day-of-week are validated against the _range of valid values. The resulting date is calculated equivalent to the following three stage approach. First, create a date on the first day of the first week _in the requested week-based-year. Then take the week-of-week-based-year, subtract one, and add the amount _in weeks to the date. Finally, adjust to the correct day-of-week within the localized week.

weekOfYear
TemporalField weekOfYear()

Returns a field to access the week of year based on this {@code WeekFields}. !(p) This represents the concept of the count of weeks within the year where weeks start on a fixed day-of-week, such as Monday. This field is typically used with {@link WeekFields#dayOfWeek()}. !(p) Week one(1) is the week starting on the {@link WeekFields#getFirstDayOfWeek} where there are at least {@link WeekFields#getMinimalDaysInFirstWeek()} days _in the year. Thus, week one may start up to {@code minDays} days before the start of the year. If the first week starts after the start of the year then the period before is week zero (0). !(p) For example:!(br) - if the 1st day of the year is a Monday, week one starts on the 1st and there is no week zero!(br) - if the 2nd day of the year is a Monday, week one starts on the 2nd and the 1st is _in week zero!(br) - if the 4th day of the year is a Monday, week one starts on the 4th and the 1st to 3rd is _in week zero!(br) - if the 5th day of the year is a Monday, week two starts on the 5th and the 1st to 4th is _in week one!(br) !(p) This field can be used with any calendar system. !(p) In the resolving phase of parsing, a date can be created from a year, week-of-year and day-of-week. !(p) In {@linkplain ResolverStyle#STRICT strict mode}, all three fields are validated against their _range of valid values. The week-of-year field is validated to ensure that the resulting year is the year requested. !(p) In {@linkplain ResolverStyle#SMART smart mode}, all three fields are validated against their _range of valid values. The week-of-year field is validated from 0 to 54, meaning that the resulting date can be _in a different year to that specified. !(p) In {@linkplain ResolverStyle#LENIENT lenient mode}, the year and day-of-week are validated against the _range of valid values. The resulting date is calculated equivalent to the following three stage approach. First, create a date on the first day of the first week _in the requested year. Then take the week-of-year, subtract one, and add the amount _in weeks to the date. Finally, adjust to the correct day-of-week within the localized week.

Static functions

ISO
WeekFields ISO()
Undocumented in source. Be warned that the author may not have intended to support it.
of
WeekFields of(Locale locale)

Obtains an instance of {@code WeekFields} appropriate for a locale. !(p) This will look up appropriate values from the provider of localization data. If the locale contains "fw" (First day of week) and/or "rg" (Region Override) <a href="../../util/Locale.html#def_locale_extension"> Unicode extensions</a>, returned instance will reflect the values specified with those extensions. If both "fw" and "rg" are specified, the value from the "fw" extension supersedes the implicit one from the "rg" extension.

of
WeekFields of(DayOfWeek firstDayOfWeek, int minimalDaysInFirstWeek)

Obtains an instance of {@code WeekFields} from the first day-of-week and minimal days. !(p) The first day-of-week defines the ISO {@code DayOfWeek} that is day 1 of the week. The minimal number of days _in the first week defines how many days must be present _in a month or year, starting from the first day-of-week, before the week is counted as the first week. A value of 1 will count the first day of the month or year as part of the first week, whereas a value of 7 will require the whole seven days to be _in the new month or year. !(p) WeekFields instances are singletons; for each unique combination of {@code firstDayOfWeek} and {@code minimalDaysInFirstWeek} the same instance will be returned.

Static variables

_ISO
WeekFields _ISO;

The ISO-8601 definition, where a week starts on Monday and the first week has a minimum of 4 days. !(p) The ISO-8601 standard defines a calendar system based on weeks. It uses the week-based-year and week-of-week-based-year concepts to split up the passage of days instead of the standard year/month/day. !(p) Note that the first week may start _in the previous calendar year. Note also that the first few days of a calendar year may be _in the week-based-year corresponding to the previous calendar year.

Meta