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*
* Copyright (c) 2011-2012, Stephen Colebourne & Michael Nascimento Santos
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package java.time.temporal;
import static java.time.temporal.ChronoField.DAY_OF_MONTH;
import static java.time.temporal.ChronoField.DAY_OF_WEEK;
import static java.time.temporal.ChronoField.DAY_OF_YEAR;
import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
import static java.time.temporal.ChronoField.YEAR;
import static java.time.temporal.ChronoUnit.DAYS;
import static java.time.temporal.ChronoUnit.FOREVER;
import static java.time.temporal.ChronoUnit.MONTHS;
import static java.time.temporal.ChronoUnit.WEEKS;
import static java.time.temporal.ChronoUnit.YEARS;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.time.DateTimeException;
import java.time.DayOfWeek;
import java.time.chrono.ChronoLocalDate;
import java.time.chrono.Chronology;
import java.time.format.ResolverStyle;
import java.util.Locale;
import java.util.Map;
import java.util.Objects;
import java.util.ResourceBundle;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import sun.util.locale.provider.CalendarDataUtility;
import sun.util.locale.provider.LocaleProviderAdapter;
import sun.util.locale.provider.LocaleResources;
/**
* 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 cellpadding="0" cellspacing="3" border="0" style="text-align: left; width: 50%;">
* <caption>Examples of WeekFields</caption>
* <tr><th>Date</th><td>Day-of-week</td>
* <td>First day: Monday<br>Minimal days: 4</td><td>First day: Monday<br>Minimal days: 5</td></tr>
* <tr><th>2008-12-31</th><td>Wednesday</td>
* <td>Week 5 of December 2008</td><td>Week 5 of December 2008</td></tr>
* <tr><th>2009-01-01</th><td>Thursday</td>
* <td>Week 1 of January 2009</td><td>Week 0 of January 2009</td></tr>
* <tr><th>2009-01-04</th><td>Sunday</td>
* <td>Week 1 of January 2009</td><td>Week 0 of January 2009</td></tr>
* <tr><th>2009-01-05</th><td>Monday</td>
* <td>Week 2 of January 2009</td><td>Week 1 of January 2009</td></tr>
* </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 cellpadding="0" cellspacing="3" border="0" style="text-align: left; width: 50%;">
* <caption>Examples of WeekFields for week-based-year</caption>
* <tr><th>Date</th><td>Day-of-week</td>
* <td>First day: Monday<br>Minimal days: 4</td><td>First day: Monday<br>Minimal days: 5</td></tr>
* <tr><th>2008-12-31</th><td>Wednesday</td>
* <td>Week 1 of 2009</td><td>Week 53 of 2008</td></tr>
* <tr><th>2009-01-01</th><td>Thursday</td>
* <td>Week 1 of 2009</td><td>Week 53 of 2008</td></tr>
* <tr><th>2009-01-04</th><td>Sunday</td>
* <td>Week 1 of 2009</td><td>Week 53 of 2008</td></tr>
* <tr><th>2009-01-05</th><td>Monday</td>
* <td>Week 2 of 2009</td><td>Week 1 of 2009</td></tr>
* </table>
*
* @implSpec
* This class is immutable and thread-safe.
*
* @since 1.8
*/
public final class WeekFields implements Serializable {
// implementation notes
// querying week-of-month or week-of-year should return the week value bound within the month/year
// however, setting the week value should be lenient (use plus/minus weeks)
// allow week-of-month outer range [0 to 6]
// allow week-of-year outer range [0 to 54]
// this is because callers shouldn't be expected to know the details of validity
/**
* The cache of rules by firstDayOfWeek plus minimalDays.
* Initialized first to be available for definition of ISO, etc.
*/
private static final ConcurrentMap<String, WeekFields> CACHE = new ConcurrentHashMap<>(4, 0.75f, 2);
/**
* 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.
*/
public static final WeekFields ISO = new WeekFields(DayOfWeek.MONDAY, 4);
/**
* The common definition of a week that starts on Sunday and the first week
* has a minimum of 1 day.
* <p>
* Defined as starting on Sunday and with a minimum of 1 day in the month.
* This week definition is in use in the US and other European countries.
*/
public static final WeekFields SUNDAY_START = WeekFields.of(DayOfWeek.SUNDAY, 1);
/**
* The unit that represents week-based-years for the purpose of addition and subtraction.
* <p>
* This allows a number of week-based-years to be added to, or subtracted from, a date.
* The unit is equal to either 52 or 53 weeks.
* The estimated duration of a week-based-year is the same as that of a standard ISO
* year at {@code 365.2425 Days}.
* <p>
* The rules for addition add the number of week-based-years to the existing value
* for the week-based-year field retaining the week-of-week-based-year
* and day-of-week, unless the week number it too large for the target year.
* In that case, the week is set to the last week of the year
* with the same day-of-week.
* <p>
* This unit is an immutable and thread-safe singleton.
*/
public static final TemporalUnit WEEK_BASED_YEARS = IsoFields.WEEK_BASED_YEARS;
/**
* Serialization version.
*/
private static final long serialVersionUID = -1177360819670808121L;
/**
* The first day-of-week.
*/
private final DayOfWeek firstDayOfWeek;
/**
* The minimal number of days in the first week.
*/
private final int minimalDays;
/**
* The field used to access the computed DayOfWeek.
*/
private final transient TemporalField dayOfWeek = ComputedDayOfField.ofDayOfWeekField(this);
/**
* The field used to access the computed WeekOfMonth.
*/
private final transient TemporalField weekOfMonth = ComputedDayOfField.ofWeekOfMonthField(this);
/**
* The field used to access the computed WeekOfYear.
*/
private final transient TemporalField weekOfYear = ComputedDayOfField.ofWeekOfYearField(this);
/**
* The field that represents the week-of-week-based-year.
* <p>
* This field allows the week of the week-based-year value to be queried and set.
* <p>
* This unit is an immutable and thread-safe singleton.
*/
private final transient TemporalField weekOfWeekBasedYear = ComputedDayOfField.ofWeekOfWeekBasedYearField(this);
/**
* The field that represents the week-based-year.
* <p>
* This field allows the week-based-year value to be queried and set.
* <p>
* This unit is an immutable and thread-safe singleton.
*/
private final transient TemporalField weekBasedYear = ComputedDayOfField.ofWeekBasedYearField(this);
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code WeekFields} appropriate for a locale.
* <p>
* This will look up appropriate values from the provider of localization data.
*
* @param locale the locale to use, not null
* @return the week-definition, not null
*/
public static WeekFields of(Locale locale) {
Objects.requireNonNull(locale, "locale");
locale = new Locale(locale.getLanguage(), locale.getCountry()); // elminate variants
int calDow = CalendarDataUtility.retrieveFirstDayOfWeek(locale);
DayOfWeek dow = DayOfWeek.SUNDAY.plus(calDow - 1);
int minDays = CalendarDataUtility.retrieveMinimalDaysInFirstWeek(locale);
return WeekFields.of(dow, minDays);
}
/**
* 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
* the same instance will be returned.
*
* @param firstDayOfWeek the first day of the week, not null
* @param minimalDaysInFirstWeek the minimal number of days in the first week, from 1 to 7
* @return the week-definition, not null
* @throws IllegalArgumentException if the minimal days value is less than one
* or greater than 7
*/
public static WeekFields of(DayOfWeek firstDayOfWeek, int minimalDaysInFirstWeek) {
String key = firstDayOfWeek.toString() + minimalDaysInFirstWeek;
WeekFields rules = CACHE.get(key);
if (rules == null) {
rules = new WeekFields(firstDayOfWeek, minimalDaysInFirstWeek);
CACHE.putIfAbsent(key, rules);
rules = CACHE.get(key);
}
return rules;
}
//-----------------------------------------------------------------------
/**
* Creates an instance of the definition.
*
* @param firstDayOfWeek the first day of the week, not null
* @param minimalDaysInFirstWeek the minimal number of days in the first week, from 1 to 7
* @throws IllegalArgumentException if the minimal days value is invalid
*/
private WeekFields(DayOfWeek firstDayOfWeek, int minimalDaysInFirstWeek) {
Objects.requireNonNull(firstDayOfWeek, "firstDayOfWeek");
if (minimalDaysInFirstWeek < 1 || minimalDaysInFirstWeek > 7) {
throw new IllegalArgumentException("Minimal number of days is invalid");
}
this.firstDayOfWeek = firstDayOfWeek;
this.minimalDays = minimalDaysInFirstWeek;
}
//-----------------------------------------------------------------------
/**
* Restore the state of a WeekFields from the stream.
* Check that the values are valid.
*
* @param s the stream to read
* @throws InvalidObjectException if the serialized object has an invalid
* value for firstDayOfWeek or minimalDays.
* @throws ClassNotFoundException if a class cannot be resolved
*/
private void readObject(ObjectInputStream s)
throws IOException, ClassNotFoundException, InvalidObjectException
{
s.defaultReadObject();
if (firstDayOfWeek == null) {
throw new InvalidObjectException("firstDayOfWeek is null");
}
if (minimalDays < 1 || minimalDays > 7) {
throw new InvalidObjectException("Minimal number of days is invalid");
}
}
/**
* Return the singleton WeekFields associated with the
* {@code firstDayOfWeek} and {@code minimalDays}.
* @return the singleton WeekFields for the firstDayOfWeek and minimalDays.
* @throws InvalidObjectException if the serialized object has invalid
* values for firstDayOfWeek or minimalDays.
*/
private Object readResolve() throws InvalidObjectException {
try {
return WeekFields.of(firstDayOfWeek, minimalDays);
} catch (IllegalArgumentException iae) {
throw new InvalidObjectException("Invalid serialized WeekFields: " + iae.getMessage());
}
}
//-----------------------------------------------------------------------
/**
* 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.
*
* @return the first day-of-week, not null
*/
public DayOfWeek getFirstDayOfWeek() {
return firstDayOfWeek;
}
/**
* 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.
*
* @return the minimal number of days in the first week of a month or year, from 1 to 7
*/
public int getMinimalDaysInFirstWeek() {
return minimalDays;
}
//-----------------------------------------------------------------------
/**
* 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.
*
* @return a field providing access to the day-of-week with localized numbering, not null
*/
public TemporalField dayOfWeek() {
return dayOfWeek;
}
/**
* 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.
*
* @return a field providing access to the week-of-month, not null
*/
public TemporalField weekOfMonth() {
return weekOfMonth;
}
/**
* 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.
*
* @return a field providing access to the week-of-year, not null
*/
public TemporalField weekOfYear() {
return weekOfYear;
}
/**
* 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.
*
* @return a field providing access to the week-of-week-based-year, not null
*/
public TemporalField weekOfWeekBasedYear() {
return weekOfWeekBasedYear;
}
/**
* 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.
*
* @return a field providing access to the week-based-year, not null
*/
public TemporalField weekBasedYear() {
return weekBasedYear;
}
//-----------------------------------------------------------------------
/**
* 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.
*
* @param object the other rules to compare to, null returns false
* @return true if this is equal to the specified rules
*/
@Override
public boolean equals(Object object) {
if (this == object) {
return true;
}
if (object instanceof WeekFields) {
return hashCode() == object.hashCode();
}
return false;
}
/**
* A hash code for this {@code WeekFields}.
*
* @return a suitable hash code
*/
@Override
public int hashCode() {
return firstDayOfWeek.ordinal() * 7 + minimalDays;
}
//-----------------------------------------------------------------------
/**
* A string representation of this {@code WeekFields} instance.
*
* @return the string representation, not null
*/
@Override
public String toString() {
return "WeekFields[" + firstDayOfWeek + ',' + minimalDays + ']';
}
//-----------------------------------------------------------------------
/**
* 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.
*/
static class ComputedDayOfField implements TemporalField {
/**
* Returns a field to access the day of week,
* computed based on a WeekFields.
* <p>
* The WeekDefintion of the first day of the week is used with
* the ISO DAY_OF_WEEK field to compute week boundaries.
*/
static ComputedDayOfField ofDayOfWeekField(WeekFields weekDef) {
return new ComputedDayOfField("DayOfWeek", weekDef, DAYS, WEEKS, DAY_OF_WEEK_RANGE);
}
/**
* Returns a field to access the week of month,
* computed based on a WeekFields.
* @see WeekFields#weekOfMonth()
*/
static ComputedDayOfField ofWeekOfMonthField(WeekFields weekDef) {
return new ComputedDayOfField("WeekOfMonth", weekDef, WEEKS, MONTHS, WEEK_OF_MONTH_RANGE);
}
/**
* Returns a field to access the week of year,
* computed based on a WeekFields.
* @see WeekFields#weekOfYear()
*/
static ComputedDayOfField ofWeekOfYearField(WeekFields weekDef) {
return new ComputedDayOfField("WeekOfYear", weekDef, WEEKS, YEARS, WEEK_OF_YEAR_RANGE);
}
/**
* Returns a field to access the week of week-based-year,
* computed based on a WeekFields.
* @see WeekFields#weekOfWeekBasedYear()
*/
static ComputedDayOfField ofWeekOfWeekBasedYearField(WeekFields weekDef) {
return new ComputedDayOfField("WeekOfWeekBasedYear", weekDef, WEEKS, IsoFields.WEEK_BASED_YEARS, WEEK_OF_WEEK_BASED_YEAR_RANGE);
}
/**
* Returns a field to access the week of week-based-year,
* computed based on a WeekFields.
* @see WeekFields#weekBasedYear()
*/
static ComputedDayOfField ofWeekBasedYearField(WeekFields weekDef) {
return new ComputedDayOfField("WeekBasedYear", weekDef, IsoFields.WEEK_BASED_YEARS, FOREVER, ChronoField.YEAR.range());
}
/**
* Return a new week-based-year date of the Chronology, year, week-of-year,
* and dow of week.
* @param chrono The chronology of the new date
* @param yowby the year of the week-based-year
* @param wowby the week of the week-based-year
* @param dow the day of the week
* @return a ChronoLocalDate for the requested year, week of year, and day of week
*/
private ChronoLocalDate ofWeekBasedYear(Chronology chrono,
int yowby, int wowby, int dow) {
ChronoLocalDate date = chrono.date(yowby, 1, 1);
int ldow = localizedDayOfWeek(date);
int offset = startOfWeekOffset(1, ldow);
// Clamp the week of year to keep it in the same year
int yearLen = date.lengthOfYear();
int newYearWeek = computeWeek(offset, yearLen + weekDef.getMinimalDaysInFirstWeek());
wowby = Math.min(wowby, newYearWeek - 1);
int days = -offset + (dow - 1) + (wowby - 1) * 7;
return date.plus(days, DAYS);
}
private final String name;
private final WeekFields weekDef;
private final TemporalUnit baseUnit;
private final TemporalUnit rangeUnit;
private final ValueRange range;
private ComputedDayOfField(String name, WeekFields weekDef, TemporalUnit baseUnit, TemporalUnit rangeUnit, ValueRange range) {
this.name = name;
this.weekDef = weekDef;
this.baseUnit = baseUnit;
this.rangeUnit = rangeUnit;
this.range = range;
}
private static final ValueRange DAY_OF_WEEK_RANGE = ValueRange.of(1, 7);
private static final ValueRange WEEK_OF_MONTH_RANGE = ValueRange.of(0, 1, 4, 6);
private static final ValueRange WEEK_OF_YEAR_RANGE = ValueRange.of(0, 1, 52, 54);
private static final ValueRange WEEK_OF_WEEK_BASED_YEAR_RANGE = ValueRange.of(1, 52, 53);
@Override
public long getFrom(TemporalAccessor temporal) {
if (rangeUnit == WEEKS) { // day-of-week
return localizedDayOfWeek(temporal);
} else if (rangeUnit == MONTHS) { // week-of-month
return localizedWeekOfMonth(temporal);
} else if (rangeUnit == YEARS) { // week-of-year
return localizedWeekOfYear(temporal);
} else if (rangeUnit == WEEK_BASED_YEARS) {
return localizedWeekOfWeekBasedYear(temporal);
} else if (rangeUnit == FOREVER) {
return localizedWeekBasedYear(temporal);
} else {
throw new IllegalStateException("unreachable, rangeUnit: " + rangeUnit + ", this: " + this);
}
}
private int localizedDayOfWeek(TemporalAccessor temporal) {
int sow = weekDef.getFirstDayOfWeek().getValue();
int isoDow = temporal.get(DAY_OF_WEEK);
return Math.floorMod(isoDow - sow, 7) + 1;
}
private int localizedDayOfWeek(int isoDow) {
int sow = weekDef.getFirstDayOfWeek().getValue();
return Math.floorMod(isoDow - sow, 7) + 1;
}
private long localizedWeekOfMonth(TemporalAccessor temporal) {
int dow = localizedDayOfWeek(temporal);
int dom = temporal.get(DAY_OF_MONTH);
int offset = startOfWeekOffset(dom, dow);
return computeWeek(offset, dom);
}
private long localizedWeekOfYear(TemporalAccessor temporal) {
int dow = localizedDayOfWeek(temporal);
int doy = temporal.get(DAY_OF_YEAR);
int offset = startOfWeekOffset(doy, dow);
return computeWeek(offset, doy);
}
/**
* Returns the year of week-based-year for the temporal.
* The year can be the previous year, the current year, or the next year.
* @param temporal a date of any chronology, not null
* @return the year of week-based-year for the date
*/
private int localizedWeekBasedYear(TemporalAccessor temporal) {
int dow = localizedDayOfWeek(temporal);
int year = temporal.get(YEAR);
int doy = temporal.get(DAY_OF_YEAR);
int offset = startOfWeekOffset(doy, dow);
int week = computeWeek(offset, doy);
if (week == 0) {
// Day is in end of week of previous year; return the previous year
return year - 1;
} else {
// If getting close to end of year, use higher precision logic
// Check if date of year is in partial week associated with next year
ValueRange dayRange = temporal.range(DAY_OF_YEAR);
int yearLen = (int)dayRange.getMaximum();
int newYearWeek = computeWeek(offset, yearLen + weekDef.getMinimalDaysInFirstWeek());
if (week >= newYearWeek) {
return year + 1;
}
}
return year;
}
/**
* Returns the week of week-based-year for the temporal.
* The week can be part of the previous year, the current year,
* or the next year depending on the week start and minimum number
* of days.
* @param temporal a date of any chronology
* @return the week of the year
* @see #localizedWeekBasedYear(java.time.temporal.TemporalAccessor)
*/
private int localizedWeekOfWeekBasedYear(TemporalAccessor temporal) {
int dow = localizedDayOfWeek(temporal);
int doy = temporal.get(DAY_OF_YEAR);
int offset = startOfWeekOffset(doy, dow);
int week = computeWeek(offset, doy);
if (week == 0) {
// Day is in end of week of previous year
// Recompute from the last day of the previous year
ChronoLocalDate date = Chronology.from(temporal).date(temporal);
date = date.minus(doy, DAYS); // Back down into previous year
return localizedWeekOfWeekBasedYear(date);
} else if (week > 50) {
// If getting close to end of year, use higher precision logic
// Check if date of year is in partial week associated with next year
ValueRange dayRange = temporal.range(DAY_OF_YEAR);
int yearLen = (int)dayRange.getMaximum();
int newYearWeek = computeWeek(offset, yearLen + weekDef.getMinimalDaysInFirstWeek());
if (week >= newYearWeek) {
// Overlaps with week of following year; reduce to week in following year
week = week - newYearWeek + 1;
}
}
return week;
}
/**
* Returns an offset to align week start with a day of month or day of year.
*
* @param day the day; 1 through infinity
* @param dow the day of the week of that day; 1 through 7
* @return an offset in days to align a day with the start of the first 'full' week
*/
private int startOfWeekOffset(int day, int dow) {
// offset of first day corresponding to the day of week in first 7 days (zero origin)
int weekStart = Math.floorMod(day - dow, 7);
int offset = -weekStart;
if (weekStart + 1 > weekDef.getMinimalDaysInFirstWeek()) {
// The previous week has the minimum days in the current month to be a 'week'
offset = 7 - weekStart;
}
return offset;
}
/**
* Returns the week number computed from the reference day and reference dayOfWeek.
*
* @param offset the offset to align a date with the start of week
* from {@link #startOfWeekOffset}.
* @param day the day for which to compute the week number
* @return the week number where zero is used for a partial week and 1 for the first full week
*/
private int computeWeek(int offset, int day) {
return ((7 + offset + (day - 1)) / 7);
}
@SuppressWarnings("unchecked")
@Override
public <R extends Temporal> R adjustInto(R temporal, long newValue) {
// Check the new value and get the old value of the field
int newVal = range.checkValidIntValue(newValue, this); // lenient check range
int currentVal = temporal.get(this);
if (newVal == currentVal) {
return temporal;
}
if (rangeUnit == FOREVER) { // replace year of WeekBasedYear
// Create a new date object with the same chronology,
// the desired year and the same week and dow.
int idow = temporal.get(weekDef.dayOfWeek);
int wowby = temporal.get(weekDef.weekOfWeekBasedYear);
return (R) ofWeekBasedYear(Chronology.from(temporal), (int)newValue, wowby, idow);
} else {
// Compute the difference and add that using the base unit of the field
return (R) temporal.plus(newVal - currentVal, baseUnit);
}
}
@Override
public ChronoLocalDate resolve(
Map<TemporalField, Long> fieldValues, TemporalAccessor partialTemporal, ResolverStyle resolverStyle) {
final long value = fieldValues.get(this);
final int newValue = Math.toIntExact(value); // broad limit makes overflow checking lighter
// first convert localized day-of-week to ISO day-of-week
// doing this first handles case where both ISO and localized were parsed and might mismatch
// day-of-week is always strict as two different day-of-week values makes lenient complex
if (rangeUnit == WEEKS) { // day-of-week
final int checkedValue = range.checkValidIntValue(value, this); // no leniency as too complex
final int startDow = weekDef.getFirstDayOfWeek().getValue();
long isoDow = Math.floorMod((startDow - 1) + (checkedValue - 1), 7) + 1;
fieldValues.remove(this);
fieldValues.put(DAY_OF_WEEK, isoDow);
return null;
}
// can only build date if ISO day-of-week is present
if (fieldValues.containsKey(DAY_OF_WEEK) == false) {
return null;
}
int isoDow = DAY_OF_WEEK.checkValidIntValue(fieldValues.get(DAY_OF_WEEK));
int dow = localizedDayOfWeek(isoDow);
// build date
Chronology chrono = Chronology.from(partialTemporal);
if (fieldValues.containsKey(YEAR)) {
int year = YEAR.checkValidIntValue(fieldValues.get(YEAR)); // validate
if (rangeUnit == MONTHS && fieldValues.containsKey(MONTH_OF_YEAR)) { // week-of-month
long month = fieldValues.get(MONTH_OF_YEAR); // not validated yet
return resolveWoM(fieldValues, chrono, year, month, newValue, dow, resolverStyle);
}
if (rangeUnit == YEARS) { // week-of-year
return resolveWoY(fieldValues, chrono, year, newValue, dow, resolverStyle);
}
} else if ((rangeUnit == WEEK_BASED_YEARS || rangeUnit == FOREVER) &&
fieldValues.containsKey(weekDef.weekBasedYear) &&
fieldValues.containsKey(weekDef.weekOfWeekBasedYear)) { // week-of-week-based-year and year-of-week-based-year
return resolveWBY(fieldValues, chrono, dow, resolverStyle);
}
return null;
}
private ChronoLocalDate resolveWoM(
Map<TemporalField, Long> fieldValues, Chronology chrono, int year, long month, long wom, int localDow, ResolverStyle resolverStyle) {
ChronoLocalDate date;
if (resolverStyle == ResolverStyle.LENIENT) {
date = chrono.date(year, 1, 1).plus(Math.subtractExact(month, 1), MONTHS);
long weeks = Math.subtractExact(wom, localizedWeekOfMonth(date));
int days = localDow - localizedDayOfWeek(date); // safe from overflow
date = date.plus(Math.addExact(Math.multiplyExact(weeks, 7), days), DAYS);
} else {
int monthValid = MONTH_OF_YEAR.checkValidIntValue(month); // validate
date = chrono.date(year, monthValid, 1);
int womInt = range.checkValidIntValue(wom, this); // validate
int weeks = (int) (womInt - localizedWeekOfMonth(date)); // safe from overflow
int days = localDow - localizedDayOfWeek(date); // safe from overflow
date = date.plus(weeks * 7 + days, DAYS);
if (resolverStyle == ResolverStyle.STRICT && date.getLong(MONTH_OF_YEAR) != month) {
throw new DateTimeException("Strict mode rejected resolved date as it is in a different month");
}
}
fieldValues.remove(this);
fieldValues.remove(YEAR);
fieldValues.remove(MONTH_OF_YEAR);
fieldValues.remove(DAY_OF_WEEK);
return date;
}
private ChronoLocalDate resolveWoY(
Map<TemporalField, Long> fieldValues, Chronology chrono, int year, long woy, int localDow, ResolverStyle resolverStyle) {
ChronoLocalDate date = chrono.date(year, 1, 1);
if (resolverStyle == ResolverStyle.LENIENT) {
long weeks = Math.subtractExact(woy, localizedWeekOfYear(date));
int days = localDow - localizedDayOfWeek(date); // safe from overflow
date = date.plus(Math.addExact(Math.multiplyExact(weeks, 7), days), DAYS);
} else {
int womInt = range.checkValidIntValue(woy, this); // validate
int weeks = (int) (womInt - localizedWeekOfYear(date)); // safe from overflow
int days = localDow - localizedDayOfWeek(date); // safe from overflow
date = date.plus(weeks * 7 + days, DAYS);
if (resolverStyle == ResolverStyle.STRICT && date.getLong(YEAR) != year) {
throw new DateTimeException("Strict mode rejected resolved date as it is in a different year");
}
}
fieldValues.remove(this);
fieldValues.remove(YEAR);
fieldValues.remove(DAY_OF_WEEK);
return date;
}
private ChronoLocalDate resolveWBY(
Map<TemporalField, Long> fieldValues, Chronology chrono, int localDow, ResolverStyle resolverStyle) {
int yowby = weekDef.weekBasedYear.range().checkValidIntValue(
fieldValues.get(weekDef.weekBasedYear), weekDef.weekBasedYear);
ChronoLocalDate date;
if (resolverStyle == ResolverStyle.LENIENT) {
date = ofWeekBasedYear(chrono, yowby, 1, localDow);
long wowby = fieldValues.get(weekDef.weekOfWeekBasedYear);
long weeks = Math.subtractExact(wowby, 1);
date = date.plus(weeks, WEEKS);
} else {
int wowby = weekDef.weekOfWeekBasedYear.range().checkValidIntValue(
fieldValues.get(weekDef.weekOfWeekBasedYear), weekDef.weekOfWeekBasedYear); // validate
date = ofWeekBasedYear(chrono, yowby, wowby, localDow);
if (resolverStyle == ResolverStyle.STRICT && localizedWeekBasedYear(date) != yowby) {
throw new DateTimeException("Strict mode rejected resolved date as it is in a different week-based-year");
}
}
fieldValues.remove(this);
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