Java tutorial
/* * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * This file is available under and governed by the GNU General Public * License version 2 only, as published by the Free Software Foundation. * However, the following notice accompanied the original version of this * file: * * Copyright (c) 2011-2012, Stephen Colebourne & Michael Nascimento Santos * * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * * Neither the name of JSR-310 nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ 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. * * <h2>Week of Month</h2> * 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> * * <h2>Week of Year</h2> * 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. * * <h2>Week Based Year</h2> * 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 */ 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. * 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. * * @param locale the locale to use, not null * @return the week-definition, not null */ public static WeekFields of(Locale locale) { Objects.requireNonNull(locale, "locale"); 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 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); fieldValues.remove(weekDef.weekBasedYear); fieldValues.remove(weekDef.weekOfWeekBasedYear); fieldValues.remove(DAY_OF_WEEK); return date; } //----------------------------------------------------------------------- @Override public String getDisplayName(Locale locale) { Objects.requireNonNull(locale, "locale"); if (rangeUnit == YEARS) { // only have values for week-of-year LocaleResources lr = LocaleProviderAdapter.getResourceBundleBased() .getLocaleResources(CalendarDataUtility.findRegionOverride(locale)); ResourceBundle rb = lr.getJavaTimeFormatData(); return rb.containsKey("field.week") ? rb.getString("field.week") : name; } return name; } @Override public TemporalUnit getBaseUnit() { return baseUnit; } @Override public TemporalUnit getRangeUnit() { return rangeUnit; } @Override public boolean isDateBased() { return true; } @Override public boolean isTimeBased() { return false; } @Override public ValueRange range() { return range; } //----------------------------------------------------------------------- @Override public boolean isSupportedBy(TemporalAccessor temporal) { if (temporal.isSupported(DAY_OF_WEEK)) { if (rangeUnit == WEEKS) { // day-of-week return true; } else if (rangeUnit == MONTHS) { // week-of-month return temporal.isSupported(DAY_OF_MONTH); } else if (rangeUnit == YEARS) { // week-of-year return temporal.isSupported(DAY_OF_YEAR); } else if (rangeUnit == WEEK_BASED_YEARS) { return temporal.isSupported(DAY_OF_YEAR); } else if (rangeUnit == FOREVER) { return temporal.isSupported(YEAR); } } return false; } @Override public ValueRange rangeRefinedBy(TemporalAccessor temporal) { if (rangeUnit == ChronoUnit.WEEKS) { // day-of-week return range; } else if (rangeUnit == MONTHS) { // week-of-month return rangeByWeek(temporal, DAY_OF_MONTH); } else if (rangeUnit == YEARS) { // week-of-year return rangeByWeek(temporal, DAY_OF_YEAR); } else if (rangeUnit == WEEK_BASED_YEARS) { return rangeWeekOfWeekBasedYear(temporal); } else if (rangeUnit == FOREVER) { return YEAR.range(); } else { throw new IllegalStateException("unreachable, rangeUnit: " + rangeUnit + ", this: " + this); } } /** * Map the field range to a week range * @param temporal the temporal * @param field the field to get the range of * @return the ValueRange with the range adjusted to weeks. */ private ValueRange rangeByWeek(TemporalAccessor temporal, TemporalField field) { int dow = localizedDayOfWeek(temporal); int offset = startOfWeekOffset(temporal.get(field), dow); ValueRange fieldRange = temporal.range(field); return ValueRange.of(computeWeek(offset, (int) fieldRange.getMinimum()), computeWeek(offset, (int) fieldRange.getMaximum())); } /** * Map the field range to a week range of a week year. * @param temporal the temporal * @return the ValueRange with the range adjusted to weeks. */ private ValueRange rangeWeekOfWeekBasedYear(TemporalAccessor temporal) { if (!temporal.isSupported(DAY_OF_YEAR)) { return WEEK_OF_YEAR_RANGE; } 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 + 7, DAYS); // Back down into previous year return rangeWeekOfWeekBasedYear(date); } // Check if day 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 weeks of following year; recompute from a week in following year ChronoLocalDate date = Chronology.from(temporal).date(temporal); date = date.plus(yearLen - doy + 1 + 7, ChronoUnit.DAYS); return rangeWeekOfWeekBasedYear(date); } return ValueRange.of(1, newYearWeek - 1); } //----------------------------------------------------------------------- @Override public String toString() { return name + "[" + weekDef.toString() + "]"; } } }