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/*
* 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) 2007-2012, 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.
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package java.time;
import static java.time.LocalTime.SECONDS_PER_DAY;
import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_MONTH;
import static java.time.temporal.ChronoField.ALIGNED_DAY_OF_WEEK_IN_YEAR;
import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_MONTH;
import static java.time.temporal.ChronoField.ALIGNED_WEEK_OF_YEAR;
import static java.time.temporal.ChronoField.DAY_OF_MONTH;
import static java.time.temporal.ChronoField.DAY_OF_YEAR;
import static java.time.temporal.ChronoField.EPOCH_DAY;
import static java.time.temporal.ChronoField.ERA;
import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
import static java.time.temporal.ChronoField.PROLEPTIC_MONTH;
import static java.time.temporal.ChronoField.YEAR;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.ObjectInputStream;
import java.io.Serializable;
import java.time.chrono.ChronoLocalDate;
import java.time.chrono.Era;
import java.time.chrono.IsoChronology;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeParseException;
import java.time.temporal.ChronoField;
import java.time.temporal.ChronoUnit;
import java.time.temporal.Temporal;
import java.time.temporal.TemporalAccessor;
import java.time.temporal.TemporalAdjuster;
import java.time.temporal.TemporalAmount;
import java.time.temporal.TemporalField;
import java.time.temporal.TemporalQueries;
import java.time.temporal.TemporalQuery;
import java.time.temporal.TemporalUnit;
import java.time.temporal.UnsupportedTemporalTypeException;
import java.time.temporal.ValueRange;
import java.time.zone.ZoneOffsetTransition;
import java.time.zone.ZoneRules;
import java.util.Objects;
/**
* A date without a time-zone in the ISO-8601 calendar system,
* such as {@code 2007-12-03}.
* <p>
* {@code LocalDate} is an immutable date-time object that represents a date,
* often viewed as year-month-day. Other date fields, such as day-of-year,
* day-of-week and week-of-year, can also be accessed.
* For example, the value "2nd October 2007" can be stored in a {@code LocalDate}.
* <p>
* This class does not store or represent a time or time-zone.
* Instead, it is a description of the date, as used for birthdays.
* It cannot represent an instant on the time-line without additional information
* such as an offset or time-zone.
* <p>
* The ISO-8601 calendar system is the modern civil calendar system used today
* in most of the world. It is equivalent to the proleptic Gregorian calendar
* system, in which today's rules for leap years are applied for all time.
* For most applications written today, the ISO-8601 rules are entirely suitable.
* However, any application that makes use of historical dates, and requires them
* to be accurate will find the ISO-8601 approach unsuitable.
*
* <p>
* This is a <a href="{@docRoot}/java/lang/doc-files/ValueBased.html">value-based</a>
* class; use of identity-sensitive operations (including reference equality
* ({@code ==}), identity hash code, or synchronization) on instances of
* {@code LocalDate} may have unpredictable results and should be avoided.
* The {@code equals} method should be used for comparisons.
*
* @implSpec
* This class is immutable and thread-safe.
*
* @since 1.8
*/
public final class LocalDate
implements Temporal, TemporalAdjuster, ChronoLocalDate, Serializable {
/**
* The minimum supported {@code LocalDate}, '-999999999-01-01'.
* This could be used by an application as a "far past" date.
*/
public static final LocalDate MIN = LocalDate.of(Year.MIN_VALUE, 1, 1);
/**
* The maximum supported {@code LocalDate}, '+999999999-12-31'.
* This could be used by an application as a "far future" date.
*/
public static final LocalDate MAX = LocalDate.of(Year.MAX_VALUE, 12, 31);
/**
* Serialization version.
*/
private static final long serialVersionUID = 2942565459149668126L;
/**
* The number of days in a 400 year cycle.
*/
private static final int DAYS_PER_CYCLE = 146097;
/**
* The number of days from year zero to year 1970.
* There are five 400 year cycles from year zero to 2000.
* There are 7 leap years from 1970 to 2000.
*/
static final long DAYS_0000_TO_1970 = (DAYS_PER_CYCLE * 5L) - (30L * 365L + 7L);
/**
* The year.
*/
private final int year;
/**
* The month-of-year.
*/
private final short month;
/**
* The day-of-month.
*/
private final short day;
//-----------------------------------------------------------------------
/**
* Obtains the current date from the system clock in the default time-zone.
* <p>
* This will query the {@link Clock#systemDefaultZone() system clock} in the default
* time-zone to obtain the current date.
* <p>
* Using this method will prevent the ability to use an alternate clock for testing
* because the clock is hard-coded.
*
* @return the current date using the system clock and default time-zone, not null
*/
public static LocalDate now() {
return now(Clock.systemDefaultZone());
}
/**
* Obtains the current date from the system clock in the specified time-zone.
* <p>
* This will query the {@link Clock#system(ZoneId) system clock} to obtain the current date.
* Specifying the time-zone avoids dependence on the default time-zone.
* <p>
* Using this method will prevent the ability to use an alternate clock for testing
* because the clock is hard-coded.
*
* @param zone the zone ID to use, not null
* @return the current date using the system clock, not null
*/
public static LocalDate now(ZoneId zone) {
return now(Clock.system(zone));
}
/**
* Obtains the current date from the specified clock.
* <p>
* This will query the specified clock to obtain the current date - today.
* Using this method allows the use of an alternate clock for testing.
* The alternate clock may be introduced using {@link Clock dependency injection}.
*
* @param clock the clock to use, not null
* @return the current date, not null
*/
public static LocalDate now(Clock clock) {
Objects.requireNonNull(clock, "clock");
// inline to avoid creating object and Instant checks
final Instant now = clock.instant(); // called once
ZoneOffset offset = clock.getZone().getRules().getOffset(now);
long epochSec = now.getEpochSecond() + offset.getTotalSeconds(); // overflow caught later
long epochDay = Math.floorDiv(epochSec, SECONDS_PER_DAY);
return LocalDate.ofEpochDay(epochDay);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code LocalDate} from a year, month and day.
* <p>
* This returns a {@code LocalDate} with the specified year, month and day-of-month.
* The day must be valid for the year and month, otherwise an exception will be thrown.
*
* @param year the year to represent, from MIN_YEAR to MAX_YEAR
* @param month the month-of-year to represent, not null
* @param dayOfMonth the day-of-month to represent, from 1 to 31
* @return the local date, not null
* @throws DateTimeException if the value of any field is out of range,
* or if the day-of-month is invalid for the month-year
*/
public static LocalDate of(int year, Month month, int dayOfMonth) {
YEAR.checkValidValue(year);
Objects.requireNonNull(month, "month");
DAY_OF_MONTH.checkValidValue(dayOfMonth);
return create(year, month.getValue(), dayOfMonth);
}
/**
* Obtains an instance of {@code LocalDate} from a year, month and day.
* <p>
* This returns a {@code LocalDate} with the specified year, month and day-of-month.
* The day must be valid for the year and month, otherwise an exception will be thrown.
*
* @param year the year to represent, from MIN_YEAR to MAX_YEAR
* @param month the month-of-year to represent, from 1 (January) to 12 (December)
* @param dayOfMonth the day-of-month to represent, from 1 to 31
* @return the local date, not null
* @throws DateTimeException if the value of any field is out of range,
* or if the day-of-month is invalid for the month-year
*/
public static LocalDate of(int year, int month, int dayOfMonth) {
YEAR.checkValidValue(year);
MONTH_OF_YEAR.checkValidValue(month);
DAY_OF_MONTH.checkValidValue(dayOfMonth);
return create(year, month, dayOfMonth);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code LocalDate} from a year and day-of-year.
* <p>
* This returns a {@code LocalDate} with the specified year and day-of-year.
* The day-of-year must be valid for the year, otherwise an exception will be thrown.
*
* @param year the year to represent, from MIN_YEAR to MAX_YEAR
* @param dayOfYear the day-of-year to represent, from 1 to 366
* @return the local date, not null
* @throws DateTimeException if the value of any field is out of range,
* or if the day-of-year is invalid for the month-year
*/
public static LocalDate ofYearDay(int year, int dayOfYear) {
YEAR.checkValidValue(year);
DAY_OF_YEAR.checkValidValue(dayOfYear);
boolean leap = IsoChronology.INSTANCE.isLeapYear(year);
if (dayOfYear == 366 && leap == false) {
throw new DateTimeException("Invalid date 'DayOfYear 366' as '" + year + "' is not a leap year");
}
Month moy = Month.of((dayOfYear - 1) / 31 + 1);
int monthEnd = moy.firstDayOfYear(leap) + moy.length(leap) - 1;
if (dayOfYear > monthEnd) {
moy = moy.plus(1);
}
int dom = dayOfYear - moy.firstDayOfYear(leap) + 1;
return new LocalDate(year, moy.getValue(), dom);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code LocalDate} from the epoch day count.
* <p>
* This returns a {@code LocalDate} with the specified epoch-day.
* The {@link ChronoField#EPOCH_DAY EPOCH_DAY} is a simple incrementing count
* of days where day 0 is 1970-01-01. Negative numbers represent earlier days.
*
* @param epochDay the Epoch Day to convert, based on the epoch 1970-01-01
* @return the local date, not null
* @throws DateTimeException if the epoch days exceeds the supported date range
*/
public static LocalDate ofEpochDay(long epochDay) {
long zeroDay = epochDay + DAYS_0000_TO_1970;
// find the march-based year
zeroDay -= 60; // adjust to 0000-03-01 so leap day is at end of four year cycle
long adjust = 0;
if (zeroDay < 0) {
// adjust negative years to positive for calculation
long adjustCycles = (zeroDay + 1) / DAYS_PER_CYCLE - 1;
adjust = adjustCycles * 400;
zeroDay += -adjustCycles * DAYS_PER_CYCLE;
}
long yearEst = (400 * zeroDay + 591) / DAYS_PER_CYCLE;
long doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
if (doyEst < 0) {
// fix estimate
yearEst--;
doyEst = zeroDay - (365 * yearEst + yearEst / 4 - yearEst / 100 + yearEst / 400);
}
yearEst += adjust; // reset any negative year
int marchDoy0 = (int) doyEst;
// convert march-based values back to january-based
int marchMonth0 = (marchDoy0 * 5 + 2) / 153;
int month = (marchMonth0 + 2) % 12 + 1;
int dom = marchDoy0 - (marchMonth0 * 306 + 5) / 10 + 1;
yearEst += marchMonth0 / 10;
// check year now we are certain it is correct
int year = YEAR.checkValidIntValue(yearEst);
return new LocalDate(year, month, dom);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code LocalDate} from a temporal object.
* <p>
* This obtains a local date based on the specified temporal.
* A {@code TemporalAccessor} represents an arbitrary set of date and time information,
* which this factory converts to an instance of {@code LocalDate}.
* <p>
* The conversion uses the {@link TemporalQueries#localDate()} query, which relies
* on extracting the {@link ChronoField#EPOCH_DAY EPOCH_DAY} field.
* <p>
* This method matches the signature of the functional interface {@link TemporalQuery}
* allowing it to be used as a query via method reference, {@code LocalDate::from}.
*
* @param temporal the temporal object to convert, not null
* @return the local date, not null
* @throws DateTimeException if unable to convert to a {@code LocalDate}
*/
public static LocalDate from(TemporalAccessor temporal) {
Objects.requireNonNull(temporal, "temporal");
LocalDate date = temporal.query(TemporalQueries.localDate());
if (date == null) {
throw new DateTimeException("Unable to obtain LocalDate from TemporalAccessor: " +
temporal + " of type " + temporal.getClass().getName());
}
return date;
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code LocalDate} from a text string such as {@code 2007-12-03}.
* <p>
* The string must represent a valid date and is parsed using
* {@link java.time.format.DateTimeFormatter#ISO_LOCAL_DATE}.
*
* @param text the text to parse such as "2007-12-03", not null
* @return the parsed local date, not null
* @throws DateTimeParseException if the text cannot be parsed
*/
public static LocalDate parse(CharSequence text) {
return parse(text, DateTimeFormatter.ISO_LOCAL_DATE);
}
/**
* Obtains an instance of {@code LocalDate} from a text string using a specific formatter.
* <p>
* The text is parsed using the formatter, returning a date.
*
* @param text the text to parse, not null
* @param formatter the formatter to use, not null
* @return the parsed local date, not null
* @throws DateTimeParseException if the text cannot be parsed
*/
public static LocalDate parse(CharSequence text, DateTimeFormatter formatter) {
Objects.requireNonNull(formatter, "formatter");
return formatter.parse(text, LocalDate::from);
}
//-----------------------------------------------------------------------
/**
* Creates a local date from the year, month and day fields.
*
* @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
* @param month the month-of-year to represent, from 1 to 12, validated
* @param dayOfMonth the day-of-month to represent, validated from 1 to 31
* @return the local date, not null
* @throws DateTimeException if the day-of-month is invalid for the month-year
*/
private static LocalDate create(int year, int month, int dayOfMonth) {
if (dayOfMonth > 28) {
int dom = 31;
switch (month) {
case 2:
dom = (IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
break;
case 4:
case 6:
case 9:
case 11:
dom = 30;
break;
}
if (dayOfMonth > dom) {
if (dayOfMonth == 29) {
throw new DateTimeException("Invalid date 'February 29' as '" + year + "' is not a leap year");
} else {
throw new DateTimeException("Invalid date '" + Month.of(month).name() + " " + dayOfMonth + "'");
}
}
}
return new LocalDate(year, month, dayOfMonth);
}
/**
* Resolves the date, resolving days past the end of month.
*
* @param year the year to represent, validated from MIN_YEAR to MAX_YEAR
* @param month the month-of-year to represent, validated from 1 to 12
* @param day the day-of-month to represent, validated from 1 to 31
* @return the resolved date, not null
*/
private static LocalDate resolvePreviousValid(int year, int month, int day) {
switch (month) {
case 2:
day = Math.min(day, IsoChronology.INSTANCE.isLeapYear(year) ? 29 : 28);
break;
case 4:
case 6:
case 9:
case 11:
day = Math.min(day, 30);
break;
}
return new LocalDate(year, month, day);
}
/**
* Constructor, previously validated.
*
* @param year the year to represent, from MIN_YEAR to MAX_YEAR
* @param month the month-of-year to represent, not null
* @param dayOfMonth the day-of-month to represent, valid for year-month, from 1 to 31
*/
private LocalDate(int year, int month, int dayOfMonth) {
this.year = year;
this.month = (short) month;
this.day = (short) dayOfMonth;
}
//-----------------------------------------------------------------------
/**
* Checks if the specified field is supported.
* <p>
* This checks if this date can be queried for the specified field.
* If false, then calling the {@link #range(TemporalField) range},
* {@link #get(TemporalField) get} and {@link #with(TemporalField, long)}
* methods will throw an exception.
* <p>
* If the field is a {@link ChronoField} then the query is implemented here.
* The supported fields are:
* <ul>
* <li>{@code DAY_OF_WEEK}
* <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH}
* <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR}
* <li>{@code DAY_OF_MONTH}
* <li>{@code DAY_OF_YEAR}
* <li>{@code EPOCH_DAY}
* <li>{@code ALIGNED_WEEK_OF_MONTH}
* <li>{@code ALIGNED_WEEK_OF_YEAR}
* <li>{@code MONTH_OF_YEAR}
* <li>{@code PROLEPTIC_MONTH}
* <li>{@code YEAR_OF_ERA}
* <li>{@code YEAR}
* <li>{@code ERA}
* </ul>
* All other {@code ChronoField} instances will return false.
* <p>
* If the field is not a {@code ChronoField}, then the result of this method
* is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
* passing {@code this} as the argument.
* Whether the field is supported is determined by the field.
*
* @param field the field to check, null returns false
* @return true if the field is supported on this date, false if not
*/
@Override // override for Javadoc
public boolean isSupported(TemporalField field) {
return ChronoLocalDate.super.isSupported(field);
}
/**
* Checks if the specified unit is supported.
* <p>
* This checks if the specified unit can be added to, or subtracted from, this date-time.
* If false, then calling the {@link #plus(long, TemporalUnit)} and
* {@link #minus(long, TemporalUnit) minus} methods will throw an exception.
* <p>
* If the unit is a {@link ChronoUnit} then the query is implemented here.
* The supported units are:
* <ul>
* <li>{@code DAYS}
* <li>{@code WEEKS}
* <li>{@code MONTHS}
* <li>{@code YEARS}
* <li>{@code DECADES}
* <li>{@code CENTURIES}
* <li>{@code MILLENNIA}
* <li>{@code ERAS}
* </ul>
* All other {@code ChronoUnit} instances will return false.
* <p>
* If the unit is not a {@code ChronoUnit}, then the result of this method
* is obtained by invoking {@code TemporalUnit.isSupportedBy(Temporal)}
* passing {@code this} as the argument.
* Whether the unit is supported is determined by the unit.
*
* @param unit the unit to check, null returns false
* @return true if the unit can be added/subtracted, false if not
*/
@Override // override for Javadoc
public boolean isSupported(TemporalUnit unit) {
return ChronoLocalDate.super.isSupported(unit);
}
//-----------------------------------------------------------------------
/**
* Gets the range of valid values for the specified field.
* <p>
* The range object expresses the minimum and maximum valid values for a field.
* This date is used to enhance the accuracy of the returned range.
* If it is not possible to return the range, because the field is not supported
* or for some other reason, an exception is thrown.
* <p>
* If the field is a {@link ChronoField} then the query is implemented here.
* The {@link #isSupported(TemporalField) supported fields} will return
* appropriate range instances.
* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
* <p>
* If the field is not a {@code ChronoField}, then the result of this method
* is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
* passing {@code this} as the argument.
* Whether the range can be obtained is determined by the field.
*
* @param field the field to query the range for, not null
* @return the range of valid values for the field, not null
* @throws DateTimeException if the range for the field cannot be obtained
* @throws UnsupportedTemporalTypeException if the field is not supported
*/
@Override
public ValueRange range(TemporalField field) {
if (field instanceof ChronoField) {
ChronoField f = (ChronoField) field;
if (f.isDateBased()) {
switch (f) {
case DAY_OF_MONTH: return ValueRange.of(1, lengthOfMonth());
case DAY_OF_YEAR: return ValueRange.of(1, lengthOfYear());
case ALIGNED_WEEK_OF_MONTH: return ValueRange.of(1, getMonth() == Month.FEBRUARY && isLeapYear() == false ? 4 : 5);
case YEAR_OF_ERA:
return (getYear() <= 0 ? ValueRange.of(1, Year.MAX_VALUE + 1) : ValueRange.of(1, Year.MAX_VALUE));
}
return field.range();
}
throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
}
return field.rangeRefinedBy(this);
}
/**
* Gets the value of the specified field from this date as an {@code int}.
* <p>
* This queries this date for the value for the specified field.
* The returned value will always be within the valid range of values for the field.
* If it is not possible to return the value, because the field is not supported
* or for some other reason, an exception is thrown.
* <p>
* If the field is a {@link ChronoField} then the query is implemented here.
* The {@link #isSupported(TemporalField) supported fields} will return valid
* values based on this date, except {@code EPOCH_DAY} and {@code PROLEPTIC_MONTH}
* which are too large to fit in an {@code int} and throw a {@code DateTimeException}.
* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
* <p>
* If the field is not a {@code ChronoField}, then the result of this method
* is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
* passing {@code this} as the argument. Whether the value can be obtained,
* and what the value represents, is determined by the field.
*
* @param field the field to get, not null
* @return the value for the field
* @throws DateTimeException if a value for the field cannot be obtained or
* the value is outside the range of valid values for the field
* @throws UnsupportedTemporalTypeException if the field is not supported or
* the range of values exceeds an {@code int}
* @throws ArithmeticException if numeric overflow occurs
*/
@Override // override for Javadoc and performance
public int get(TemporalField field) {
if (field instanceof ChronoField) {
return get0(field);
}
return ChronoLocalDate.super.get(field);
}
/**
* Gets the value of the specified field from this date as a {@code long}.
* <p>
* This queries this date for the value for the specified field.
* If it is not possible to return the value, because the field is not supported
* or for some other reason, an exception is thrown.
* <p>
* If the field is a {@link ChronoField} then the query is implemented here.
* The {@link #isSupported(TemporalField) supported fields} will return valid
* values based on this date.
* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
* <p>
* If the field is not a {@code ChronoField}, then the result of this method
* is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
* passing {@code this} as the argument. Whether the value can be obtained,
* and what the value represents, is determined by the field.
*
* @param field the field to get, not null
* @return the value for the field
* @throws DateTimeException if a value for the field cannot be obtained
* @throws UnsupportedTemporalTypeException if the field is not supported
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public long getLong(TemporalField field) {
if (field instanceof ChronoField) {
if (field == EPOCH_DAY) {
return toEpochDay();
}
if (field == PROLEPTIC_MONTH) {
return getProlepticMonth();
}
return get0(field);
}
return field.getFrom(this);
}
private int get0(TemporalField field) {
switch ((ChronoField) field) {
case DAY_OF_WEEK: return getDayOfWeek().getValue();
case ALIGNED_DAY_OF_WEEK_IN_MONTH: return ((day - 1) % 7) + 1;
case ALIGNED_DAY_OF_WEEK_IN_YEAR: return ((getDayOfYear() - 1) % 7) + 1;
case DAY_OF_MONTH: return day;
case DAY_OF_YEAR: return getDayOfYear();
case EPOCH_DAY: throw new UnsupportedTemporalTypeException("Invalid field 'EpochDay' for get() method, use getLong() instead");
case ALIGNED_WEEK_OF_MONTH: return ((day - 1) / 7) + 1;
case ALIGNED_WEEK_OF_YEAR: return ((getDayOfYear() - 1) / 7) + 1;
case MONTH_OF_YEAR: return month;
case PROLEPTIC_MONTH: throw new UnsupportedTemporalTypeException("Invalid field 'ProlepticMonth' for get() method, use getLong() instead");
case YEAR_OF_ERA: return (year >= 1 ? year : 1 - year);
case YEAR: return year;
case ERA: return (year >= 1 ? 1 : 0);
}
throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
}
private long getProlepticMonth() {
return (year * 12L + month - 1);
}
//-----------------------------------------------------------------------
/**
* Gets the chronology of this date, which is the ISO calendar system.
* <p>
* The {@code Chronology} represents the calendar system in use.
* The ISO-8601 calendar system is the modern civil calendar system used today
* in most of the world. It is equivalent to the proleptic Gregorian calendar
* system, in which today's rules for leap years are applied for all time.
*
* @return the ISO chronology, not null
*/
@Override
public IsoChronology getChronology() {
return IsoChronology.INSTANCE;
}
/**
* Gets the era applicable at this date.
* <p>
* The official ISO-8601 standard does not define eras, however {@code IsoChronology} does.
* It defines two eras, 'CE' from year one onwards and 'BCE' from year zero backwards.
* Since dates before the Julian-Gregorian cutover are not in line with history,
* the cutover between 'BCE' and 'CE' is also not aligned with the commonly used
* eras, often referred to using 'BC' and 'AD'.
* <p>
* Users of this class should typically ignore this method as it exists primarily
* to fulfill the {@link ChronoLocalDate} contract where it is necessary to support
* the Japanese calendar system.
* <p>
* The returned era will be a singleton capable of being compared with the constants
* in {@link IsoChronology} using the {@code ==} operator.
*
* @return the {@code IsoChronology} era constant applicable at this date, not null
*/
@Override // override for Javadoc
public Era getEra() {
return ChronoLocalDate.super.getEra();
}
/**
* Gets the year field.
* <p>
* This method returns the primitive {@code int} value for the year.
* <p>
* The year returned by this method is proleptic as per {@code get(YEAR)}.
* To obtain the year-of-era, use {@code get(YEAR_OF_ERA)}.
*
* @return the year, from MIN_YEAR to MAX_YEAR
*/
public int getYear() {
return year;
}
/**
* Gets the month-of-year field from 1 to 12.
* <p>
* This method returns the month as an {@code int} from 1 to 12.
* Application code is frequently clearer if the enum {@link Month}
* is used by calling {@link #getMonth()}.
*
* @return the month-of-year, from 1 to 12
* @see #getMonth()
*/
public int getMonthValue() {
return month;
}
/**
* Gets the month-of-year field using the {@code Month} enum.
* <p>
* This method returns the enum {@link Month} for the month.
* This avoids confusion as to what {@code int} values mean.
* If you need access to the primitive {@code int} value then the enum
* provides the {@link Month#getValue() int value}.
*
* @return the month-of-year, not null
* @see #getMonthValue()
*/
public Month getMonth() {
return Month.of(month);
}
/**
* Gets the day-of-month field.
* <p>
* This method returns the primitive {@code int} value for the day-of-month.
*
* @return the day-of-month, from 1 to 31
*/
public int getDayOfMonth() {
return day;
}
/**
* Gets the day-of-year field.
* <p>
* This method returns the primitive {@code int} value for the day-of-year.
*
* @return the day-of-year, from 1 to 365, or 366 in a leap year
*/
public int getDayOfYear() {
return getMonth().firstDayOfYear(isLeapYear()) + day - 1;
}
/**
* Gets the day-of-week field, which is an enum {@code DayOfWeek}.
* <p>
* This method returns the enum {@link DayOfWeek} for the day-of-week.
* This avoids confusion as to what {@code int} values mean.
* If you need access to the primitive {@code int} value then the enum
* provides the {@link DayOfWeek#getValue() int value}.
* <p>
* Additional information can be obtained from the {@code DayOfWeek}.
* This includes textual names of the values.
*
* @return the day-of-week, not null
*/
public DayOfWeek getDayOfWeek() {
int dow0 = (int)Math.floorMod(toEpochDay() + 3, 7);
return DayOfWeek.of(dow0 + 1);
}
//-----------------------------------------------------------------------
/**
* Checks if the year is a leap year, according to the ISO proleptic
* calendar system rules.
* <p>
* This method applies the current rules for leap years across the whole time-line.
* In general, a year is a leap year if it is divisible by four without
* remainder. However, years divisible by 100, are not leap years, with
* the exception of years divisible by 400 which are.
* <p>
* For example, 1904 is a leap year it is divisible by 4.
* 1900 was not a leap year as it is divisible by 100, however 2000 was a
* leap year as it is divisible by 400.
* <p>
* The calculation is proleptic - applying the same rules into the far future and far past.
* This is historically inaccurate, but is correct for the ISO-8601 standard.
*
* @return true if the year is leap, false otherwise
*/
@Override // override for Javadoc and performance
public boolean isLeapYear() {
return IsoChronology.INSTANCE.isLeapYear(year);
}
/**
* Returns the length of the month represented by this date.
* <p>
* This returns the length of the month in days.
* For example, a date in January would return 31.
*
* @return the length of the month in days
*/
@Override
public int lengthOfMonth() {
switch (month) {
case 2:
return (isLeapYear() ? 29 : 28);
case 4:
case 6:
case 9:
case 11:
return 30;
default:
return 31;
}
}
/**
* Returns the length of the year represented by this date.
* <p>
* This returns the length of the year in days, either 365 or 366.
*
* @return 366 if the year is leap, 365 otherwise
*/
@Override // override for Javadoc and performance
public int lengthOfYear() {
return (isLeapYear() ? 366 : 365);
}
//-----------------------------------------------------------------------
/**
* Returns an adjusted copy of this date.
* <p>
* This returns a {@code LocalDate}, based on this one, with the date adjusted.
* The adjustment takes place using the specified adjuster strategy object.
* Read the documentation of the adjuster to understand what adjustment will be made.
* <p>
* A simple adjuster might simply set the one of the fields, such as the year field.
* A more complex adjuster might set the date to the last day of the month.
* A selection of common adjustments is provided in {@link TemporalAdjuster}.
* These include finding the "last day of the month" and "next Wednesday".
* Key date-time classes also implement the {@code TemporalAdjuster} interface,
* such as {@link Month} and {@link java.time.MonthDay MonthDay}.
* The adjuster is responsible for handling special cases, such as the varying
* lengths of month and leap years.
* <p>
* For example this code returns a date on the last day of July:
* <pre>
* import static java.time.Month.*;
* import static java.time.temporal.Adjusters.*;
*
* result = localDate.with(JULY).with(lastDayOfMonth());
* </pre>
* <p>
* The result of this method is obtained by invoking the
* {@link TemporalAdjuster#adjustInto(Temporal)} method on the
* specified adjuster passing {@code this} as the argument.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param adjuster the adjuster to use, not null
* @return a {@code LocalDate} based on {@code this} with the adjustment made, not null
* @throws DateTimeException if the adjustment cannot be made
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public LocalDate with(TemporalAdjuster adjuster) {
// optimizations
if (adjuster instanceof LocalDate) {
return (LocalDate) adjuster;
}
return (LocalDate) adjuster.adjustInto(this);
}
/**
* Returns a copy of this date with the specified field set to a new value.
* <p>
* This returns a {@code LocalDate}, based on this one, with the value
* for the specified field changed.
* This can be used to change any supported field, such as the year, month or day-of-month.
* If it is not possible to set the value, because the field is not supported or for
* some other reason, an exception is thrown.
* <p>
* In some cases, changing the specified field can cause the resulting date to become invalid,
* such as changing the month from 31st January to February would make the day-of-month invalid.
* In cases like this, the field is responsible for resolving the date. Typically it will choose
* the previous valid date, which would be the last valid day of February in this example.
* <p>
* If the field is a {@link ChronoField} then the adjustment is implemented here.
* The supported fields behave as follows:
* <ul>
* <li>{@code DAY_OF_WEEK} -
* Returns a {@code LocalDate} with the specified day-of-week.
* The date is adjusted up to 6 days forward or backward within the boundary
* of a Monday to Sunday week.
* <li>{@code ALIGNED_DAY_OF_WEEK_IN_MONTH} -
* Returns a {@code LocalDate} with the specified aligned-day-of-week.
* The date is adjusted to the specified month-based aligned-day-of-week.
* Aligned weeks are counted such that the first week of a given month starts
* on the first day of that month.
* This may cause the date to be moved up to 6 days into the following month.
* <li>{@code ALIGNED_DAY_OF_WEEK_IN_YEAR} -
* Returns a {@code LocalDate} with the specified aligned-day-of-week.
* The date is adjusted to the specified year-based aligned-day-of-week.
* Aligned weeks are counted such that the first week of a given year starts
* on the first day of that year.
* This may cause the date to be moved up to 6 days into the following year.
* <li>{@code DAY_OF_MONTH} -
* Returns a {@code LocalDate} with the specified day-of-month.
* The month and year will be unchanged. If the day-of-month is invalid for the
* year and month, then a {@code DateTimeException} is thrown.
* <li>{@code DAY_OF_YEAR} -
* Returns a {@code LocalDate} with the specified day-of-year.
* The year will be unchanged. If the day-of-year is invalid for the
* year, then a {@code DateTimeException} is thrown.
* <li>{@code EPOCH_DAY} -
* Returns a {@code LocalDate} with the specified epoch-day.
* This completely replaces the date and is equivalent to {@link #ofEpochDay(long)}.
* <li>{@code ALIGNED_WEEK_OF_MONTH} -
* Returns a {@code LocalDate} with the specified aligned-week-of-month.
* Aligned weeks are counted such that the first week of a given month starts
* on the first day of that month.
* This adjustment moves the date in whole week chunks to match the specified week.
* The result will have the same day-of-week as this date.
* This may cause the date to be moved into the following month.
* <li>{@code ALIGNED_WEEK_OF_YEAR} -
* Returns a {@code LocalDate} with the specified aligned-week-of-year.
* Aligned weeks are counted such that the first week of a given year starts
* on the first day of that year.
* This adjustment moves the date in whole week chunks to match the specified week.
* The result will have the same day-of-week as this date.
* This may cause the date to be moved into the following year.
* <li>{@code MONTH_OF_YEAR} -
* Returns a {@code LocalDate} with the specified month-of-year.
* The year will be unchanged. The day-of-month will also be unchanged,
* unless it would be invalid for the new month and year. In that case, the
* day-of-month is adjusted to the maximum valid value for the new month and year.
* <li>{@code PROLEPTIC_MONTH} -
* Returns a {@code LocalDate} with the specified proleptic-month.
* The day-of-month will be unchanged, unless it would be invalid for the new month
* and year. In that case, the day-of-month is adjusted to the maximum valid value
* for the new month and year.
* <li>{@code YEAR_OF_ERA} -
* Returns a {@code LocalDate} with the specified year-of-era.
* The era and month will be unchanged. The day-of-month will also be unchanged,
* unless it would be invalid for the new month and year. In that case, the
* day-of-month is adjusted to the maximum valid value for the new month and year.
* <li>{@code YEAR} -
* Returns a {@code LocalDate} with the specified year.
* The month will be unchanged. The day-of-month will also be unchanged,
* unless it would be invalid for the new month and year. In that case, the
* day-of-month is adjusted to the maximum valid value for the new month and year.
* <li>{@code ERA} -
* Returns a {@code LocalDate} with the specified era.
* The year-of-era and month will be unchanged. The day-of-month will also be unchanged,
* unless it would be invalid for the new month and year. In that case, the
* day-of-month is adjusted to the maximum valid value for the new month and year.
* </ul>
* <p>
* In all cases, if the new value is outside the valid range of values for the field
* then a {@code DateTimeException} will be thrown.
* <p>
* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
* <p>
* If the field is not a {@code ChronoField}, then the result of this method
* is obtained by invoking {@code TemporalField.adjustInto(Temporal, long)}
* passing {@code this} as the argument. In this case, the field determines
* whether and how to adjust the instant.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param field the field to set in the result, not null
* @param newValue the new value of the field in the result
* @return a {@code LocalDate} based on {@code this} with the specified field set, not null
* @throws DateTimeException if the field cannot be set
* @throws UnsupportedTemporalTypeException if the field is not supported
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public LocalDate with(TemporalField field, long newValue) {
if (field instanceof ChronoField) {
ChronoField f = (ChronoField) field;
f.checkValidValue(newValue);
switch (f) {
case DAY_OF_WEEK: return plusDays(newValue - getDayOfWeek().getValue());
case ALIGNED_DAY_OF_WEEK_IN_MONTH: return plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_MONTH));
case ALIGNED_DAY_OF_WEEK_IN_YEAR: return plusDays(newValue - getLong(ALIGNED_DAY_OF_WEEK_IN_YEAR));
case DAY_OF_MONTH: return withDayOfMonth((int) newValue);
case DAY_OF_YEAR: return withDayOfYear((int) newValue);
case EPOCH_DAY: return LocalDate.ofEpochDay(newValue);
case ALIGNED_WEEK_OF_MONTH: return plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_MONTH));
case ALIGNED_WEEK_OF_YEAR: return plusWeeks(newValue - getLong(ALIGNED_WEEK_OF_YEAR));
case MONTH_OF_YEAR: return withMonth((int) newValue);
case PROLEPTIC_MONTH: return plusMonths(newValue - getProlepticMonth());
case YEAR_OF_ERA: return withYear((int) (year >= 1 ? newValue : 1 - newValue));
case YEAR: return withYear((int) newValue);
case ERA: return (getLong(ERA) == newValue ? this : withYear(1 - year));
}
throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
}
return field.adjustInto(this, newValue);
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this date with the year altered.
* If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param year the year to set in the result, from MIN_YEAR to MAX_YEAR
* @return a {@code LocalDate} based on this date with the requested year, not null
* @throws DateTimeException if the year value is invalid
*/
public LocalDate withYear(int year) {
if (this.year == year) {
return this;
}
YEAR.checkValidValue(year);
return resolvePreviousValid(year, month, day);
}
/**
* Returns a copy of this date with the month-of-year altered.
* If the day-of-month is invalid for the year, it will be changed to the last valid day of the month.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param month the month-of-year to set in the result, from 1 (January) to 12 (December)
* @return a {@code LocalDate} based on this date with the requested month, not null
* @throws DateTimeException if the month-of-year value is invalid
*/
public LocalDate withMonth(int month) {
if (this.month == month) {
return this;
}
MONTH_OF_YEAR.checkValidValue(month);
return resolvePreviousValid(year, month, day);
}
/**
* Returns a copy of this date with the day-of-month altered.
* If the resulting date is invalid, an exception is thrown.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param dayOfMonth the day-of-month to set in the result, from 1 to 28-31
* @return a {@code LocalDate} based on this date with the requested day, not null
* @throws DateTimeException if the day-of-month value is invalid,
* or if the day-of-month is invalid for the month-year
*/
public LocalDate withDayOfMonth(int dayOfMonth) {
if (this.day == dayOfMonth) {
return this;
}
return of(year, month, dayOfMonth);
}
/**
* Returns a copy of this date with the day-of-year altered.
* If the resulting date is invalid, an exception is thrown.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param dayOfYear the day-of-year to set in the result, from 1 to 365-366
* @return a {@code LocalDate} based on this date with the requested day, not null
* @throws DateTimeException if the day-of-year value is invalid,
* or if the day-of-year is invalid for the year
*/
public LocalDate withDayOfYear(int dayOfYear) {
if (this.getDayOfYear() == dayOfYear) {
return this;
}
return ofYearDay(year, dayOfYear);
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this date with the specified amount added.
* <p>
* This returns a {@code LocalDate}, based on this one, with the specified amount added.
* The amount is typically {@link Period} but may be any other type implementing
* the {@link TemporalAmount} interface.
* <p>
* The calculation is delegated to the amount object by calling
* {@link TemporalAmount#addTo(Temporal)}. The amount implementation is free
* to implement the addition in any way it wishes, however it typically
* calls back to {@link #plus(long, TemporalUnit)}. Consult the documentation
* of the amount implementation to determine if it can be successfully added.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param amountToAdd the amount to add, not null
* @return a {@code LocalDate} based on this date with the addition made, not null
* @throws DateTimeException if the addition cannot be made
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public LocalDate plus(TemporalAmount amountToAdd) {
if (amountToAdd instanceof Period) {
Period periodToAdd = (Period) amountToAdd;
return plusMonths(periodToAdd.toTotalMonths()).plusDays(periodToAdd.getDays());
}
Objects.requireNonNull(amountToAdd, "amountToAdd");
return (LocalDate) amountToAdd.addTo(this);
}
/**
* Returns a copy of this date with the specified amount added.
* <p>
* This returns a {@code LocalDate}, based on this one, with the amount
* in terms of the unit added. If it is not possible to add the amount, because the
* unit is not supported or for some other reason, an exception is thrown.
* <p>
* In some cases, adding the amount can cause the resulting date to become invalid.
* For example, adding one month to 31st January would result in 31st February.
* In cases like this, the unit is responsible for resolving the date.
* Typically it will choose the previous valid date, which would be the last valid
* day of February in this example.
* <p>
* If the field is a {@link ChronoUnit} then the addition is implemented here.
* The supported fields behave as follows:
* <ul>
* <li>{@code DAYS} -
* Returns a {@code LocalDate} with the specified number of days added.
* This is equivalent to {@link #plusDays(long)}.
* <li>{@code WEEKS} -
* Returns a {@code LocalDate} with the specified number of weeks added.
* This is equivalent to {@link #plusWeeks(long)} and uses a 7 day week.
* <li>{@code MONTHS} -
* Returns a {@code LocalDate} with the specified number of months added.
* This is equivalent to {@link #plusMonths(long)}.
* The day-of-month will be unchanged unless it would be invalid for the new
* month and year. In that case, the day-of-month is adjusted to the maximum
* valid value for the new month and year.
* <li>{@code YEARS} -
* Returns a {@code LocalDate} with the specified number of years added.
* This is equivalent to {@link #plusYears(long)}.
* The day-of-month will be unchanged unless it would be invalid for the new
* month and year. In that case, the day-of-month is adjusted to the maximum
* valid value for the new month and year.
* <li>{@code DECADES} -
* Returns a {@code LocalDate} with the specified number of decades added.
* This is equivalent to calling {@link #plusYears(long)} with the amount
* multiplied by 10.
* The day-of-month will be unchanged unless it would be invalid for the new
* month and year. In that case, the day-of-month is adjusted to the maximum
* valid value for the new month and year.
* <li>{@code CENTURIES} -
* Returns a {@code LocalDate} with the specified number of centuries added.
* This is equivalent to calling {@link #plusYears(long)} with the amount
* multiplied by 100.
* The day-of-month will be unchanged unless it would be invalid for the new
* month and year. In that case, the day-of-month is adjusted to the maximum
* valid value for the new month and year.
* <li>{@code MILLENNIA} -
* Returns a {@code LocalDate} with the specified number of millennia added.
* This is equivalent to calling {@link #plusYears(long)} with the amount
* multiplied by 1,000.
* The day-of-month will be unchanged unless it would be invalid for the new
* month and year. In that case, the day-of-month is adjusted to the maximum
* valid value for the new month and year.
* <li>{@code ERAS} -
* Returns a {@code LocalDate} with the specified number of eras added.
* Only two eras are supported so the amount must be one, zero or minus one.
* If the amount is non-zero then the year is changed such that the year-of-era
* is unchanged.
* The day-of-month will be unchanged unless it would be invalid for the new
* month and year. In that case, the day-of-month is adjusted to the maximum
* valid value for the new month and year.
* </ul>
* <p>
* All other {@code ChronoUnit} instances will throw an {@code UnsupportedTemporalTypeException}.
* <p>
* If the field is not a {@code ChronoUnit}, then the result of this method
* is obtained by invoking {@code TemporalUnit.addTo(Temporal, long)}
* passing {@code this} as the argument. In this case, the unit determines
* whether and how to perform the addition.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param amountToAdd the amount of the unit to add to the result, may be negative
* @param unit the unit of the amount to add, not null
* @return a {@code LocalDate} based on this date with the specified amount added, not null
* @throws DateTimeException if the addition cannot be made
* @throws UnsupportedTemporalTypeException if the unit is not supported
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public LocalDate plus(long amountToAdd, TemporalUnit unit) {
if (unit instanceof ChronoUnit) {
ChronoUnit f = (ChronoUnit) unit;
switch (f) {
case DAYS: return plusDays(amountToAdd);
case WEEKS: return plusWeeks(amountToAdd);
case MONTHS: return plusMonths(amountToAdd);
case YEARS: return plusYears(amountToAdd);
case DECADES: return plusYears(Math.multiplyExact(amountToAdd, 10));
case CENTURIES: return plusYears(Math.multiplyExact(amountToAdd, 100));
case MILLENNIA: return plusYears(Math.multiplyExact(amountToAdd, 1000));
case ERAS: return with(ERA, Math.addExact(getLong(ERA), amountToAdd));
}
throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
}
return unit.addTo(this, amountToAdd);
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this {@code LocalDate} with the specified period in years added.
* <p>
* This method adds the specified amount to the years field in three steps:
* <ol>
* <li>Add the input years to the year field</li>
* <li>Check if the resulting date would be invalid</li>
* <li>Adjust the day-of-month to the last valid day if necessary</li>
* </ol>
* <p>
* For example, 2008-02-29 (leap year) plus one year would result in the
* invalid date 2009-02-29 (standard year). Instead of returning an invalid
* result, the last valid day of the month, 2009-02-28, is selected instead.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param yearsToAdd the years to add, may be negative
* @return a {@code LocalDate} based on this date with the years added, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate plusYears(long yearsToAdd) {
if (yearsToAdd == 0) {
return this;
}
int newYear = YEAR.checkValidIntValue(year + yearsToAdd); // safe overflow
return resolvePreviousValid(newYear, month, day);
}
/**
* Returns a copy of this {@code LocalDate} with the specified period in months added.
* <p>
* This method adds the specified amount to the months field in three steps:
* <ol>
* <li>Add the input months to the month-of-year field</li>
* <li>Check if the resulting date would be invalid</li>
* <li>Adjust the day-of-month to the last valid day if necessary</li>
* </ol>
* <p>
* For example, 2007-03-31 plus one month would result in the invalid date
* 2007-04-31. Instead of returning an invalid result, the last valid day
* of the month, 2007-04-30, is selected instead.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param monthsToAdd the months to add, may be negative
* @return a {@code LocalDate} based on this date with the months added, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate plusMonths(long monthsToAdd) {
if (monthsToAdd == 0) {
return this;
}
long monthCount = year * 12L + (month - 1);
long calcMonths = monthCount + monthsToAdd; // safe overflow
int newYear = YEAR.checkValidIntValue(Math.floorDiv(calcMonths, 12));
int newMonth = (int)Math.floorMod(calcMonths, 12) + 1;
return resolvePreviousValid(newYear, newMonth, day);
}
/**
* Returns a copy of this {@code LocalDate} with the specified period in weeks added.
* <p>
* This method adds the specified amount in weeks to the days field incrementing
* the month and year fields as necessary to ensure the result remains valid.
* The result is only invalid if the maximum/minimum year is exceeded.
* <p>
* For example, 2008-12-31 plus one week would result in 2009-01-07.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param weeksToAdd the weeks to add, may be negative
* @return a {@code LocalDate} based on this date with the weeks added, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate plusWeeks(long weeksToAdd) {
return plusDays(Math.multiplyExact(weeksToAdd, 7));
}
/**
* Returns a copy of this {@code LocalDate} with the specified number of days added.
* <p>
* This method adds the specified amount to the days field incrementing the
* month and year fields as necessary to ensure the result remains valid.
* The result is only invalid if the maximum/minimum year is exceeded.
* <p>
* For example, 2008-12-31 plus one day would result in 2009-01-01.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param daysToAdd the days to add, may be negative
* @return a {@code LocalDate} based on this date with the days added, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate plusDays(long daysToAdd) {
if (daysToAdd == 0) {
return this;
}
long mjDay = Math.addExact(toEpochDay(), daysToAdd);
return LocalDate.ofEpochDay(mjDay);
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this date with the specified amount subtracted.
* <p>
* This returns a {@code LocalDate}, based on this one, with the specified amount subtracted.
* The amount is typically {@link Period} but may be any other type implementing
* the {@link TemporalAmount} interface.
* <p>
* The calculation is delegated to the amount object by calling
* {@link TemporalAmount#subtractFrom(Temporal)}. The amount implementation is free
* to implement the subtraction in any way it wishes, however it typically
* calls back to {@link #minus(long, TemporalUnit)}. Consult the documentation
* of the amount implementation to determine if it can be successfully subtracted.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param amountToSubtract the amount to subtract, not null
* @return a {@code LocalDate} based on this date with the subtraction made, not null
* @throws DateTimeException if the subtraction cannot be made
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public LocalDate minus(TemporalAmount amountToSubtract) {
if (amountToSubtract instanceof Period) {
Period periodToSubtract = (Period) amountToSubtract;
return minusMonths(periodToSubtract.toTotalMonths()).minusDays(periodToSubtract.getDays());
}
Objects.requireNonNull(amountToSubtract, "amountToSubtract");
return (LocalDate) amountToSubtract.subtractFrom(this);
}
/**
* Returns a copy of this date with the specified amount subtracted.
* <p>
* This returns a {@code LocalDate}, based on this one, with the amount
* in terms of the unit subtracted. If it is not possible to subtract the amount,
* because the unit is not supported or for some other reason, an exception is thrown.
* <p>
* This method is equivalent to {@link #plus(long, TemporalUnit)} with the amount negated.
* See that method for a full description of how addition, and thus subtraction, works.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param amountToSubtract the amount of the unit to subtract from the result, may be negative
* @param unit the unit of the amount to subtract, not null
* @return a {@code LocalDate} based on this date with the specified amount subtracted, not null
* @throws DateTimeException if the subtraction cannot be made
* @throws UnsupportedTemporalTypeException if the unit is not supported
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public LocalDate minus(long amountToSubtract, TemporalUnit unit) {
return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this {@code LocalDate} with the specified period in years subtracted.
* <p>
* This method subtracts the specified amount from the years field in three steps:
* <ol>
* <li>Subtract the input years to the year field</li>
* <li>Check if the resulting date would be invalid</li>
* <li>Adjust the day-of-month to the last valid day if necessary</li>
* </ol>
* <p>
* For example, 2008-02-29 (leap year) minus one year would result in the
* invalid date 2007-02-29 (standard year). Instead of returning an invalid
* result, the last valid day of the month, 2007-02-28, is selected instead.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param yearsToSubtract the years to subtract, may be negative
* @return a {@code LocalDate} based on this date with the years subtracted, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate minusYears(long yearsToSubtract) {
return (yearsToSubtract == Long.MIN_VALUE ? plusYears(Long.MAX_VALUE).plusYears(1) : plusYears(-yearsToSubtract));
}
/**
* Returns a copy of this {@code LocalDate} with the specified period in months subtracted.
* <p>
* This method subtracts the specified amount from the months field in three steps:
* <ol>
* <li>Subtract the input months to the month-of-year field</li>
* <li>Check if the resulting date would be invalid</li>
* <li>Adjust the day-of-month to the last valid day if necessary</li>
* </ol>
* <p>
* For example, 2007-03-31 minus one month would result in the invalid date
* 2007-02-31. Instead of returning an invalid result, the last valid day
* of the month, 2007-02-28, is selected instead.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param monthsToSubtract the months to subtract, may be negative
* @return a {@code LocalDate} based on this date with the months subtracted, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate minusMonths(long monthsToSubtract) {
return (monthsToSubtract == Long.MIN_VALUE ? plusMonths(Long.MAX_VALUE).plusMonths(1) : plusMonths(-monthsToSubtract));
}
/**
* Returns a copy of this {@code LocalDate} with the specified period in weeks subtracted.
* <p>
* This method subtracts the specified amount in weeks from the days field decrementing
* the month and year fields as necessary to ensure the result remains valid.
* The result is only invalid if the maximum/minimum year is exceeded.
* <p>
* For example, 2009-01-07 minus one week would result in 2008-12-31.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param weeksToSubtract the weeks to subtract, may be negative
* @return a {@code LocalDate} based on this date with the weeks subtracted, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate minusWeeks(long weeksToSubtract) {
return (weeksToSubtract == Long.MIN_VALUE ? plusWeeks(Long.MAX_VALUE).plusWeeks(1) : plusWeeks(-weeksToSubtract));
}
/**
* Returns a copy of this {@code LocalDate} with the specified number of days subtracted.
* <p>
* This method subtracts the specified amount from the days field decrementing the
* month and year fields as necessary to ensure the result remains valid.
* The result is only invalid if the maximum/minimum year is exceeded.
* <p>
* For example, 2009-01-01 minus one day would result in 2008-12-31.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param daysToSubtract the days to subtract, may be negative
* @return a {@code LocalDate} based on this date with the days subtracted, not null
* @throws DateTimeException if the result exceeds the supported date range
*/
public LocalDate minusDays(long daysToSubtract) {
return (daysToSubtract == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-daysToSubtract));
}
//-----------------------------------------------------------------------
/**
* Queries this date using the specified query.
* <p>
* This queries this date using the specified query strategy object.
* The {@code TemporalQuery} object defines the logic to be used to
* obtain the result. Read the documentation of the query to understand
* what the result of this method will be.
* <p>
* The result of this method is obtained by invoking the
* {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
* specified query passing {@code this} as the argument.
*
* @param <R> the type of the result
* @param query the query to invoke, not null
* @return the query result, null may be returned (defined by the query)
* @throws DateTimeException if unable to query (defined by the query)
* @throws ArithmeticException if numeric overflow occurs (defined by the query)
*/
@SuppressWarnings("unchecked")
@Override
public <R> R query(TemporalQuery<R> query) {
if (query == TemporalQueries.localDate()) {
return (R) this;
}
return ChronoLocalDate.super.query(query);
}
/**
* Adjusts the specified temporal object to have the same date as this object.
* <p>
* This returns a temporal object of the same observable type as the input
* with the date changed to be the same as this.
* <p>
* The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
* passing {@link ChronoField#EPOCH_DAY} as the field.
* <p>
* In most cases, it is clearer to reverse the calling pattern by using
* {@link Temporal#with(TemporalAdjuster)}:
* <pre>
* // these two lines are equivalent, but the second approach is recommended
* temporal = thisLocalDate.adjustInto(temporal);
* temporal = temporal.with(thisLocalDate);
* </pre>
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param temporal the target object to be adjusted, not null
* @return the adjusted object, not null
* @throws DateTimeException if unable to make the adjustment
* @throws ArithmeticException if numeric overflow occurs
*/
@Override // override for Javadoc
public Temporal adjustInto(Temporal temporal) {
return ChronoLocalDate.super.adjustInto(temporal);
}
/**
* Calculates the amount of time until another date in terms of the specified unit.
* <p>
* This calculates the amount of time between two {@code LocalDate}
* objects in terms of a single {@code TemporalUnit}.
* The start and end points are {@code this} and the specified date.
* The result will be negative if the end is before the start.
* The {@code Temporal} passed to this method is converted to a
* {@code LocalDate} using {@link #from(TemporalAccessor)}.
* For example, the amount in days between two dates can be calculated
* using {@code startDate.until(endDate, DAYS)}.
* <p>
* The calculation returns a whole number, representing the number of
* complete units between the two dates.
* For example, the amount in months between 2012-06-15 and 2012-08-14
* will only be one month as it is one day short of two months.
* <p>
* There are two equivalent ways of using this method.
* The first is to invoke this method.
* The second is to use {@link TemporalUnit#between(Temporal, Temporal)}:
* <pre>
* // these two lines are equivalent
* amount = start.until(end, MONTHS);
* amount = MONTHS.between(start, end);
* </pre>
* The choice should be made based on which makes the code more readable.
* <p>
* The calculation is implemented in this method for {@link ChronoUnit}.
* The units {@code DAYS}, {@code WEEKS}, {@code MONTHS}, {@code YEARS},
* {@code DECADES}, {@code CENTURIES}, {@code MILLENNIA} and {@code ERAS}
* are supported. Other {@code ChronoUnit} values will throw an exception.
* <p>
* If the unit is not a {@code ChronoUnit}, then the result of this method
* is obtained by invoking {@code TemporalUnit.between(Temporal, Temporal)}
* passing {@code this} as the first argument and the converted input temporal
* as the second argument.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param endExclusive the end date, exclusive, which is converted to a {@code LocalDate}, not null
* @param unit the unit to measure the amount in, not null
* @return the amount of time between this date and the end date
* @throws DateTimeException if the amount cannot be calculated, or the end
* temporal cannot be converted to a {@code LocalDate}
* @throws UnsupportedTemporalTypeException if the unit is not supported
* @throws ArithmeticException if numeric overflow occurs
*/
@Override
public long until(Temporal endExclusive, TemporalUnit unit) {
LocalDate end = LocalDate.from(endExclusive);
if (unit instanceof ChronoUnit) {
switch ((ChronoUnit) unit) {
case DAYS: return daysUntil(end);
case WEEKS: return daysUntil(end) / 7;
case MONTHS: return monthsUntil(end);
case YEARS: return monthsUntil(end) / 12;
case DECADES: return monthsUntil(end) / 120;
case CENTURIES: return monthsUntil(end) / 1200;
case MILLENNIA: return monthsUntil(end) / 12000;
case ERAS: return end.getLong(ERA) - getLong(ERA);
}
throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
}
return unit.between(this, end);
}
long daysUntil(LocalDate end) {
return end.toEpochDay() - toEpochDay(); // no overflow
}
private long monthsUntil(LocalDate end) {
long packed1 = getProlepticMonth() * 32L + getDayOfMonth(); // no overflow
long packed2 = end.getProlepticMonth() * 32L + end.getDayOfMonth(); // no overflow
return (packed2 - packed1) / 32;
}
/**
* Calculates the period between this date and another date as a {@code Period}.
* <p>
* This calculates the period between two dates in terms of years, months and days.
* The start and end points are {@code this} and the specified date.
* The result will be negative if the end is before the start.
* The negative sign will be the same in each of year, month and day.
* <p>
* The calculation is performed using the ISO calendar system.
* If necessary, the input date will be converted to ISO.
* <p>
* The start date is included, but the end date is not.
* The period is calculated by removing complete months, then calculating
* the remaining number of days, adjusting to ensure that both have the same sign.
* The number of months is then normalized into years and months based on a 12 month year.
* A month is considered to be complete if the end day-of-month is greater
* than or equal to the start day-of-month.
* For example, from {@code 2010-01-15} to {@code 2011-03-18} is "1 year, 2 months and 3 days".
* <p>
* There are two equivalent ways of using this method.
* The first is to invoke this method.
* The second is to use {@link Period#between(LocalDate, LocalDate)}:
* <pre>
* // these two lines are equivalent
* period = start.until(end);
* period = Period.between(start, end);
* </pre>
* The choice should be made based on which makes the code more readable.
*
* @param endDateExclusive the end date, exclusive, which may be in any chronology, not null
* @return the period between this date and the end date, not null
*/
@Override
public Period until(ChronoLocalDate endDateExclusive) {
LocalDate end = LocalDate.from(endDateExclusive);
long totalMonths = end.getProlepticMonth() - this.getProlepticMonth(); // safe
int days = end.day - this.day;
if (totalMonths > 0 && days < 0) {
totalMonths--;
LocalDate calcDate = this.plusMonths(totalMonths);
days = (int) (end.toEpochDay() - calcDate.toEpochDay()); // safe
} else if (totalMonths < 0 && days > 0) {
totalMonths++;
days -= end.lengthOfMonth();
}
long years = totalMonths / 12; // safe
int months = (int) (totalMonths % 12); // safe
return Period.of(Math.toIntExact(years), months, days);
}
/**
* Formats this date using the specified formatter.
* <p>
* This date will be passed to the formatter to produce a string.
*
* @param formatter the formatter to use, not null
* @return the formatted date string, not null
* @throws DateTimeException if an error occurs during printing
*/
@Override // override for Javadoc and performance
public String format(DateTimeFormatter formatter) {
Objects.requireNonNull(formatter, "formatter");
return formatter.format(this);
}
//-----------------------------------------------------------------------
/**
* Combines this date with a time to create a {@code LocalDateTime}.
* <p>
* This returns a {@code LocalDateTime} formed from this date at the specified time.
* All possible combinations of date and time are valid.
*
* @param time the time to combine with, not null
* @return the local date-time formed from this date and the specified time, not null
*/
@Override
public LocalDateTime atTime(LocalTime time) {
return LocalDateTime.of(this, time);
}
/**
* Combines this date with a time to create a {@code LocalDateTime}.
* <p>
* This returns a {@code LocalDateTime} formed from this date at the
* specified hour and minute.
* The seconds and nanosecond fields will be set to zero.
* The individual time fields must be within their valid range.
* All possible combinations of date and time are valid.
*
* @param hour the hour-of-day to use, from 0 to 23
* @param minute the minute-of-hour to use, from 0 to 59
* @return the local date-time formed from this date and the specified time, not null
* @throws DateTimeException if the value of any field is out of range
*/
public LocalDateTime atTime(int hour, int minute) {
return atTime(LocalTime.of(hour, minute));
}
/**
* Combines this date with a time to create a {@code LocalDateTime}.
* <p>
* This returns a {@code LocalDateTime} formed from this date at the
* specified hour, minute and second.
* The nanosecond field will be set to zero.
* The individual time fields must be within their valid range.
* All possible combinations of date and time are valid.
*
* @param hour the hour-of-day to use, from 0 to 23
* @param minute the minute-of-hour to use, from 0 to 59
* @param second the second-of-minute to represent, from 0 to 59
* @return the local date-time formed from this date and the specified time, not null
* @throws DateTimeException if the value of any field is out of range
*/
public LocalDateTime atTime(int hour, int minute, int second) {
return atTime(LocalTime.of(hour, minute, second));
}
/**
* Combines this date with a time to create a {@code LocalDateTime}.
* <p>
* This returns a {@code LocalDateTime} formed from this date at the
* specified hour, minute, second and nanosecond.
* The individual time fields must be within their valid range.
* All possible combinations of date and time are valid.
*
* @param hour the hour-of-day to use, from 0 to 23
* @param minute the minute-of-hour to use, from 0 to 59
* @param second the second-of-minute to represent, from 0 to 59
* @param nanoOfSecond the nano-of-second to represent, from 0 to 999,999,999
* @return the local date-time formed from this date and the specified time, not null
* @throws DateTimeException if the value of any field is out of range
*/
public LocalDateTime atTime(int hour, int minute, int second, int nanoOfSecond) {
return atTime(LocalTime.of(hour, minute, second, nanoOfSecond));
}
/**
* Combines this date with an offset time to create an {@code OffsetDateTime}.
* <p>
* This returns an {@code OffsetDateTime} formed from this date at the specified time.
* All possible combinations of date and time are valid.
*
* @param time the time to combine with, not null
* @return the offset date-time formed from this date and the specified time, not null
*/
public OffsetDateTime atTime(OffsetTime time) {
return OffsetDateTime.of(LocalDateTime.of(this, time.toLocalTime()), time.getOffset());
}
/**
* Combines this date with the time of midnight to create a {@code LocalDateTime}
* at the start of this date.
* <p>
* This returns a {@code LocalDateTime} formed from this date at the time of
* midnight, 00:00, at the start of this date.
*
* @return the local date-time of midnight at the start of this date, not null
*/
public LocalDateTime atStartOfDay() {
return LocalDateTime.of(this, LocalTime.MIDNIGHT);
}
/**
* Returns a zoned date-time from this date at the earliest valid time according
* to the rules in the time-zone.
* <p>
* Time-zone rules, such as daylight savings, mean that not every local date-time
* is valid for the specified zone, thus the local date-time may not be midnight.
* <p>
* In most cases, there is only one valid offset for a local date-time.
* In the case of an overlap, there are two valid offsets, and the earlier one is used,
* corresponding to the first occurrence of midnight on the date.
* In the case of a gap, the zoned date-time will represent the instant just after the gap.
* <p>
* If the zone ID is a {@link ZoneOffset}, then the result always has a time of midnight.
* <p>
* To convert to a specific time in a given time-zone call {@link #atTime(LocalTime)}
* followed by {@link LocalDateTime#atZone(ZoneId)}.
*
* @param zone the zone ID to use, not null
* @return the zoned date-time formed from this date and the earliest valid time for the zone, not null
*/
public ZonedDateTime atStartOfDay(ZoneId zone) {
Objects.requireNonNull(zone, "zone");
// need to handle case where there is a gap from 11:30 to 00:30
// standard ZDT factory would result in 01:00 rather than 00:30
LocalDateTime ldt = atTime(LocalTime.MIDNIGHT);
if (zone instanceof ZoneOffset == false) {
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