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* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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/*
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* Copyright (c) 2008-2012, 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:
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* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
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* may be used to endorse or promote products derived from this software
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package java.time;
import static java.time.temporal.
ChronoUnit.
DAYS;
import static java.time.temporal.
ChronoUnit.
MONTHS;
import static java.time.temporal.
ChronoUnit.
YEARS;
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.
ChronoPeriod;
import java.time.chrono.
Chronology;
import java.time.chrono.
IsoChronology;
import java.time.format.
DateTimeParseException;
import java.time.temporal.
ChronoUnit;
import java.time.temporal.
Temporal;
import java.time.temporal.
TemporalAccessor;
import java.time.temporal.
TemporalAmount;
import java.time.temporal.
TemporalQueries;
import java.time.temporal.
TemporalUnit;
import java.time.temporal.
UnsupportedTemporalTypeException;
import java.util.
Arrays;
import java.util.
Collections;
import java.util.
List;
import java.util.
Objects;
import java.util.regex.
Matcher;
import java.util.regex.
Pattern;
/**
* A date-based amount of time in the ISO-8601 calendar system,
* such as '2 years, 3 months and 4 days'.
* <p>
* This class models a quantity or amount of time in terms of years, months and days.
* See {@link Duration} for the time-based equivalent to this class.
* <p>
* Durations and periods differ in their treatment of daylight savings time
* when added to {@link ZonedDateTime}. A {@code Duration} will add an exact
* number of seconds, thus a duration of one day is always exactly 24 hours.
* By contrast, a {@code Period} will add a conceptual day, trying to maintain
* the local time.
* <p>
* For example, consider adding a period of one day and a duration of one day to
* 18:00 on the evening before a daylight savings gap. The {@code Period} will add
* the conceptual day and result in a {@code ZonedDateTime} at 18:00 the following day.
* By contrast, the {@code Duration} will add exactly 24 hours, resulting in a
* {@code ZonedDateTime} at 19:00 the following day (assuming a one hour DST gap).
* <p>
* The supported units of a period are {@link ChronoUnit#YEARS YEARS},
* {@link ChronoUnit#MONTHS MONTHS} and {@link ChronoUnit#DAYS DAYS}.
* All three fields are always present, but may be set to zero.
* <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.
* <p>
* The period is modeled as a directed amount of time, meaning that individual parts of the
* period may be negative.
*
* <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 Period} 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
Period
implements
ChronoPeriod,
Serializable {
/**
* A constant for a period of zero.
*/
public static final
Period ZERO = new
Period(0, 0, 0);
/**
* Serialization version.
*/
private static final long
serialVersionUID = -3587258372562876L;
/**
* The pattern for parsing.
*/
private static final
Pattern PATTERN =
Pattern.
compile("([-+]?)P(?:([-+]?[0-9]+)Y)?(?:([-+]?[0-9]+)M)?(?:([-+]?[0-9]+)W)?(?:([-+]?[0-9]+)D)?",
Pattern.
CASE_INSENSITIVE);
/**
* The set of supported units.
*/
private static final
List<
TemporalUnit>
SUPPORTED_UNITS =
Collections.
unmodifiableList(
Arrays.<
TemporalUnit>
asList(
YEARS,
MONTHS,
DAYS));
/**
* The number of years.
*/
private final int
years;
/**
* The number of months.
*/
private final int
months;
/**
* The number of days.
*/
private final int
days;
//-----------------------------------------------------------------------
/**
* Obtains a {@code Period} representing a number of years.
* <p>
* The resulting period will have the specified years.
* The months and days units will be zero.
*
* @param years the number of years, positive or negative
* @return the period of years, not null
*/
public static
Period ofYears(int
years) {
return
create(
years, 0, 0);
}
/**
* Obtains a {@code Period} representing a number of months.
* <p>
* The resulting period will have the specified months.
* The years and days units will be zero.
*
* @param months the number of months, positive or negative
* @return the period of months, not null
*/
public static
Period ofMonths(int
months) {
return
create(0,
months, 0);
}
/**
* Obtains a {@code Period} representing a number of weeks.
* <p>
* The resulting period will be day-based, with the amount of days
* equal to the number of weeks multiplied by 7.
* The years and months units will be zero.
*
* @param weeks the number of weeks, positive or negative
* @return the period, with the input weeks converted to days, not null
*/
public static
Period ofWeeks(int
weeks) {
return
create(0, 0,
Math.
multiplyExact(
weeks, 7));
}
/**
* Obtains a {@code Period} representing a number of days.
* <p>
* The resulting period will have the specified days.
* The years and months units will be zero.
*
* @param days the number of days, positive or negative
* @return the period of days, not null
*/
public static
Period ofDays(int
days) {
return
create(0, 0,
days);
}
//-----------------------------------------------------------------------
/**
* Obtains a {@code Period} representing a number of years, months and days.
* <p>
* This creates an instance based on years, months and days.
*
* @param years the amount of years, may be negative
* @param months the amount of months, may be negative
* @param days the amount of days, may be negative
* @return the period of years, months and days, not null
*/
public static
Period of(int
years, int
months, int
days) {
return
create(
years,
months,
days);
}
//-----------------------------------------------------------------------
/**
* Obtains an instance of {@code Period} from a temporal amount.
* <p>
* This obtains a period based on the specified amount.
* A {@code TemporalAmount} represents an amount of time, which may be
* date-based or time-based, which this factory extracts to a {@code Period}.
* <p>
* The conversion loops around the set of units from the amount and uses
* the {@link ChronoUnit#YEARS YEARS}, {@link ChronoUnit#MONTHS MONTHS}
* and {@link ChronoUnit#DAYS DAYS} units to create a period.
* If any other units are found then an exception is thrown.
* <p>
* If the amount is a {@code ChronoPeriod} then it must use the ISO chronology.
*
* @param amount the temporal amount to convert, not null
* @return the equivalent period, not null
* @throws DateTimeException if unable to convert to a {@code Period}
* @throws ArithmeticException if the amount of years, months or days exceeds an int
*/
public static
Period from(
TemporalAmount amount) {
if (
amount instanceof
Period) {
return (
Period)
amount;
}
if (
amount instanceof
ChronoPeriod) {
if (
IsoChronology.
INSTANCE.
equals(((
ChronoPeriod)
amount).
getChronology()) == false) {
throw new
DateTimeException("Period requires ISO chronology: " +
amount);
}
}
Objects.
requireNonNull(
amount, "amount");
int
years = 0;
int
months = 0;
int
days = 0;
for (
TemporalUnit unit :
amount.
getUnits()) {
long
unitAmount =
amount.
get(
unit);
if (
unit ==
ChronoUnit.
YEARS) {
years =
Math.
toIntExact(
unitAmount);
} else if (
unit ==
ChronoUnit.
MONTHS) {
months =
Math.
toIntExact(
unitAmount);
} else if (
unit ==
ChronoUnit.
DAYS) {
days =
Math.
toIntExact(
unitAmount);
} else {
throw new
DateTimeException("Unit must be Years, Months or Days, but was " +
unit);
}
}
return
create(
years,
months,
days);
}
//-----------------------------------------------------------------------
/**
* Obtains a {@code Period} from a text string such as {@code PnYnMnD}.
* <p>
* This will parse the string produced by {@code toString()} which is
* based on the ISO-8601 period formats {@code PnYnMnD} and {@code PnW}.
* <p>
* The string starts with an optional sign, denoted by the ASCII negative
* or positive symbol. If negative, the whole period is negated.
* The ASCII letter "P" is next in upper or lower case.
* There are then four sections, each consisting of a number and a suffix.
* At least one of the four sections must be present.
* The sections have suffixes in ASCII of "Y", "M", "W" and "D" for
* years, months, weeks and days, accepted in upper or lower case.
* The suffixes must occur in order.
* The number part of each section must consist of ASCII digits.
* The number may be prefixed by the ASCII negative or positive symbol.
* The number must parse to an {@code int}.
* <p>
* The leading plus/minus sign, and negative values for other units are
* not part of the ISO-8601 standard. In addition, ISO-8601 does not
* permit mixing between the {@code PnYnMnD} and {@code PnW} formats.
* Any week-based input is multiplied by 7 and treated as a number of days.
* <p>
* For example, the following are valid inputs:
* <pre>
* "P2Y" -- Period.ofYears(2)
* "P3M" -- Period.ofMonths(3)
* "P4W" -- Period.ofWeeks(4)
* "P5D" -- Period.ofDays(5)
* "P1Y2M3D" -- Period.of(1, 2, 3)
* "P1Y2M3W4D" -- Period.of(1, 2, 25)
* "P-1Y2M" -- Period.of(-1, 2, 0)
* "-P1Y2M" -- Period.of(-1, -2, 0)
* </pre>
*
* @param text the text to parse, not null
* @return the parsed period, not null
* @throws DateTimeParseException if the text cannot be parsed to a period
*/
public static
Period parse(
CharSequence text) {
Objects.
requireNonNull(
text, "text");
Matcher matcher =
PATTERN.
matcher(
text);
if (
matcher.
matches()) {
int
negate = ("-".
equals(
matcher.
group(1)) ? -1 : 1);
String yearMatch =
matcher.
group(2);
String monthMatch =
matcher.
group(3);
String weekMatch =
matcher.
group(4);
String dayMatch =
matcher.
group(5);
if (
yearMatch != null ||
monthMatch != null ||
dayMatch != null ||
weekMatch != null) {
try {
int
years =
parseNumber(
text,
yearMatch,
negate);
int
months =
parseNumber(
text,
monthMatch,
negate);
int
weeks =
parseNumber(
text,
weekMatch,
negate);
int
days =
parseNumber(
text,
dayMatch,
negate);
days =
Math.
addExact(
days,
Math.
multiplyExact(
weeks, 7));
return
create(
years,
months,
days);
} catch (
NumberFormatException ex) {
throw new
DateTimeParseException("Text cannot be parsed to a Period",
text, 0,
ex);
}
}
}
throw new
DateTimeParseException("Text cannot be parsed to a Period",
text, 0);
}
private static int
parseNumber(
CharSequence text,
String str, int
negate) {
if (
str == null) {
return 0;
}
int
val =
Integer.
parseInt(
str);
try {
return
Math.
multiplyExact(
val,
negate);
} catch (
ArithmeticException ex) {
throw new
DateTimeParseException("Text cannot be parsed to a Period",
text, 0,
ex);
}
}
//-----------------------------------------------------------------------
/**
* Obtains a {@code Period} consisting of the number of years, months,
* and days between two dates.
* <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 split into years and months based on a 12 month year.
* A month is considered 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 one year, two months and three days.
* <p>
* The result of this method can be a negative period if the end is before the start.
* The negative sign will be the same in each of year, month and day.
*
* @param startDateInclusive the start date, inclusive, not null
* @param endDateExclusive the end date, exclusive, not null
* @return the period between this date and the end date, not null
* @see ChronoLocalDate#until(ChronoLocalDate)
*/
public static
Period between(
LocalDate startDateInclusive,
LocalDate endDateExclusive) {
return
startDateInclusive.
until(
endDateExclusive);
}
//-----------------------------------------------------------------------
/**
* Creates an instance.
*
* @param years the amount
* @param months the amount
* @param days the amount
*/
private static
Period create(int
years, int
months, int
days) {
if ((
years |
months |
days) == 0) {
return
ZERO;
}
return new
Period(
years,
months,
days);
}
/**
* Constructor.
*
* @param years the amount
* @param months the amount
* @param days the amount
*/
private
Period(int
years, int
months, int
days) {
this.
years =
years;
this.
months =
months;
this.
days =
days;
}
//-----------------------------------------------------------------------
/**
* Gets the value of the requested unit.
* <p>
* This returns a value for each of the three supported units,
* {@link ChronoUnit#YEARS YEARS}, {@link ChronoUnit#MONTHS MONTHS} and
* {@link ChronoUnit#DAYS DAYS}.
* All other units throw an exception.
*
* @param unit the {@code TemporalUnit} for which to return the value
* @return the long value of the unit
* @throws DateTimeException if the unit is not supported
* @throws UnsupportedTemporalTypeException if the unit is not supported
*/
@
Override
public long
get(
TemporalUnit unit) {
if (
unit ==
ChronoUnit.
YEARS) {
return
getYears();
} else if (
unit ==
ChronoUnit.
MONTHS) {
return
getMonths();
} else if (
unit ==
ChronoUnit.
DAYS) {
return
getDays();
} else {
throw new
UnsupportedTemporalTypeException("Unsupported unit: " +
unit);
}
}
/**
* Gets the set of units supported by this period.
* <p>
* The supported units are {@link ChronoUnit#YEARS YEARS},
* {@link ChronoUnit#MONTHS MONTHS} and {@link ChronoUnit#DAYS DAYS}.
* They are returned in the order years, months, days.
* <p>
* This set can be used in conjunction with {@link #get(TemporalUnit)}
* to access the entire state of the period.
*
* @return a list containing the years, months and days units, not null
*/
@
Override
public
List<
TemporalUnit>
getUnits() {
return
SUPPORTED_UNITS;
}
/**
* Gets the chronology of this period, 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;
}
//-----------------------------------------------------------------------
/**
* Checks if all three units of this period are zero.
* <p>
* A zero period has the value zero for the years, months and days units.
*
* @return true if this period is zero-length
*/
public boolean
isZero() {
return (this ==
ZERO);
}
/**
* Checks if any of the three units of this period are negative.
* <p>
* This checks whether the years, months or days units are less than zero.
*
* @return true if any unit of this period is negative
*/
public boolean
isNegative() {
return
years < 0 ||
months < 0 ||
days < 0;
}
//-----------------------------------------------------------------------
/**
* Gets the amount of years of this period.
* <p>
* This returns the years unit.
* <p>
* The months unit is not automatically normalized with the years unit.
* This means that a period of "15 months" is different to a period
* of "1 year and 3 months".
*
* @return the amount of years of this period, may be negative
*/
public int
getYears() {
return
years;
}
/**
* Gets the amount of months of this period.
* <p>
* This returns the months unit.
* <p>
* The months unit is not automatically normalized with the years unit.
* This means that a period of "15 months" is different to a period
* of "1 year and 3 months".
*
* @return the amount of months of this period, may be negative
*/
public int
getMonths() {
return
months;
}
/**
* Gets the amount of days of this period.
* <p>
* This returns the days unit.
*
* @return the amount of days of this period, may be negative
*/
public int
getDays() {
return
days;
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this period with the specified amount of years.
* <p>
* This sets the amount of the years unit in a copy of this period.
* The months and days units are unaffected.
* <p>
* The months unit is not automatically normalized with the years unit.
* This means that a period of "15 months" is different to a period
* of "1 year and 3 months".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param years the years to represent, may be negative
* @return a {@code Period} based on this period with the requested years, not null
*/
public
Period withYears(int
years) {
if (
years == this.
years) {
return this;
}
return
create(
years,
months,
days);
}
/**
* Returns a copy of this period with the specified amount of months.
* <p>
* This sets the amount of the months unit in a copy of this period.
* The years and days units are unaffected.
* <p>
* The months unit is not automatically normalized with the years unit.
* This means that a period of "15 months" is different to a period
* of "1 year and 3 months".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param months the months to represent, may be negative
* @return a {@code Period} based on this period with the requested months, not null
*/
public
Period withMonths(int
months) {
if (
months == this.
months) {
return this;
}
return
create(
years,
months,
days);
}
/**
* Returns a copy of this period with the specified amount of days.
* <p>
* This sets the amount of the days unit in a copy of this period.
* The years and months units are unaffected.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param days the days to represent, may be negative
* @return a {@code Period} based on this period with the requested days, not null
*/
public
Period withDays(int
days) {
if (
days == this.
days) {
return this;
}
return
create(
years,
months,
days);
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this period with the specified period added.
* <p>
* This operates separately on the years, months and days.
* No normalization is performed.
* <p>
* For example, "1 year, 6 months and 3 days" plus "2 years, 2 months and 2 days"
* returns "3 years, 8 months and 5 days".
* <p>
* The specified amount is typically an instance of {@code Period}.
* Other types are interpreted using {@link Period#from(TemporalAmount)}.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param amountToAdd the amount to add, not null
* @return a {@code Period} based on this period with the requested period added, not null
* @throws DateTimeException if the specified amount has a non-ISO chronology or
* contains an invalid unit
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period plus(
TemporalAmount amountToAdd) {
Period isoAmount =
Period.
from(
amountToAdd);
return
create(
Math.
addExact(
years,
isoAmount.
years),
Math.
addExact(
months,
isoAmount.
months),
Math.
addExact(
days,
isoAmount.
days));
}
/**
* Returns a copy of this period with the specified years added.
* <p>
* This adds the amount to the years unit in a copy of this period.
* The months and days units are unaffected.
* For example, "1 year, 6 months and 3 days" plus 2 years returns "3 years, 6 months and 3 days".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param yearsToAdd the years to add, positive or negative
* @return a {@code Period} based on this period with the specified years added, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period plusYears(long
yearsToAdd) {
if (
yearsToAdd == 0) {
return this;
}
return
create(
Math.
toIntExact(
Math.
addExact(
years,
yearsToAdd)),
months,
days);
}
/**
* Returns a copy of this period with the specified months added.
* <p>
* This adds the amount to the months unit in a copy of this period.
* The years and days units are unaffected.
* For example, "1 year, 6 months and 3 days" plus 2 months returns "1 year, 8 months and 3 days".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param monthsToAdd the months to add, positive or negative
* @return a {@code Period} based on this period with the specified months added, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period plusMonths(long
monthsToAdd) {
if (
monthsToAdd == 0) {
return this;
}
return
create(
years,
Math.
toIntExact(
Math.
addExact(
months,
monthsToAdd)),
days);
}
/**
* Returns a copy of this period with the specified days added.
* <p>
* This adds the amount to the days unit in a copy of this period.
* The years and months units are unaffected.
* For example, "1 year, 6 months and 3 days" plus 2 days returns "1 year, 6 months and 5 days".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param daysToAdd the days to add, positive or negative
* @return a {@code Period} based on this period with the specified days added, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period plusDays(long
daysToAdd) {
if (
daysToAdd == 0) {
return this;
}
return
create(
years,
months,
Math.
toIntExact(
Math.
addExact(
days,
daysToAdd)));
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this period with the specified period subtracted.
* <p>
* This operates separately on the years, months and days.
* No normalization is performed.
* <p>
* For example, "1 year, 6 months and 3 days" minus "2 years, 2 months and 2 days"
* returns "-1 years, 4 months and 1 day".
* <p>
* The specified amount is typically an instance of {@code Period}.
* Other types are interpreted using {@link Period#from(TemporalAmount)}.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param amountToSubtract the amount to subtract, not null
* @return a {@code Period} based on this period with the requested period subtracted, not null
* @throws DateTimeException if the specified amount has a non-ISO chronology or
* contains an invalid unit
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period minus(
TemporalAmount amountToSubtract) {
Period isoAmount =
Period.
from(
amountToSubtract);
return
create(
Math.
subtractExact(
years,
isoAmount.
years),
Math.
subtractExact(
months,
isoAmount.
months),
Math.
subtractExact(
days,
isoAmount.
days));
}
/**
* Returns a copy of this period with the specified years subtracted.
* <p>
* This subtracts the amount from the years unit in a copy of this period.
* The months and days units are unaffected.
* For example, "1 year, 6 months and 3 days" minus 2 years returns "-1 years, 6 months and 3 days".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param yearsToSubtract the years to subtract, positive or negative
* @return a {@code Period} based on this period with the specified years subtracted, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period minusYears(long
yearsToSubtract) {
return (
yearsToSubtract ==
Long.
MIN_VALUE ?
plusYears(
Long.
MAX_VALUE).
plusYears(1) :
plusYears(-
yearsToSubtract));
}
/**
* Returns a copy of this period with the specified months subtracted.
* <p>
* This subtracts the amount from the months unit in a copy of this period.
* The years and days units are unaffected.
* For example, "1 year, 6 months and 3 days" minus 2 months returns "1 year, 4 months and 3 days".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param monthsToSubtract the years to subtract, positive or negative
* @return a {@code Period} based on this period with the specified months subtracted, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period minusMonths(long
monthsToSubtract) {
return (
monthsToSubtract ==
Long.
MIN_VALUE ?
plusMonths(
Long.
MAX_VALUE).
plusMonths(1) :
plusMonths(-
monthsToSubtract));
}
/**
* Returns a copy of this period with the specified days subtracted.
* <p>
* This subtracts the amount from the days unit in a copy of this period.
* The years and months units are unaffected.
* For example, "1 year, 6 months and 3 days" minus 2 days returns "1 year, 6 months and 1 day".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param daysToSubtract the months to subtract, positive or negative
* @return a {@code Period} based on this period with the specified days subtracted, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period minusDays(long
daysToSubtract) {
return (
daysToSubtract ==
Long.
MIN_VALUE ?
plusDays(
Long.
MAX_VALUE).
plusDays(1) :
plusDays(-
daysToSubtract));
}
//-----------------------------------------------------------------------
/**
* Returns a new instance with each element in this period multiplied
* by the specified scalar.
* <p>
* This returns a period with each of the years, months and days units
* individually multiplied.
* For example, a period of "2 years, -3 months and 4 days" multiplied by
* 3 will return "6 years, -9 months and 12 days".
* No normalization is performed.
*
* @param scalar the scalar to multiply by, not null
* @return a {@code Period} based on this period with the amounts multiplied by the scalar, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period multipliedBy(int
scalar) {
if (this ==
ZERO ||
scalar == 1) {
return this;
}
return
create(
Math.
multiplyExact(
years,
scalar),
Math.
multiplyExact(
months,
scalar),
Math.
multiplyExact(
days,
scalar));
}
/**
* Returns a new instance with each amount in this period negated.
* <p>
* This returns a period with each of the years, months and days units
* individually negated.
* For example, a period of "2 years, -3 months and 4 days" will be
* negated to "-2 years, 3 months and -4 days".
* No normalization is performed.
*
* @return a {@code Period} based on this period with the amounts negated, not null
* @throws ArithmeticException if numeric overflow occurs, which only happens if
* one of the units has the value {@code Long.MIN_VALUE}
*/
public
Period negated() {
return
multipliedBy(-1);
}
//-----------------------------------------------------------------------
/**
* Returns a copy of this period with the years and months normalized.
* <p>
* This normalizes the years and months units, leaving the days unit unchanged.
* The months unit is adjusted to have an absolute value less than 11,
* with the years unit being adjusted to compensate. For example, a period of
* "1 Year and 15 months" will be normalized to "2 years and 3 months".
* <p>
* The sign of the years and months units will be the same after normalization.
* For example, a period of "1 year and -25 months" will be normalized to
* "-1 year and -1 month".
* <p>
* This instance is immutable and unaffected by this method call.
*
* @return a {@code Period} based on this period with excess months normalized to years, not null
* @throws ArithmeticException if numeric overflow occurs
*/
public
Period normalized() {
long
totalMonths =
toTotalMonths();
long
splitYears =
totalMonths / 12;
int
splitMonths = (int) (
totalMonths % 12); // no overflow
if (
splitYears ==
years &&
splitMonths ==
months) {
return this;
}
return
create(
Math.
toIntExact(
splitYears),
splitMonths,
days);
}
/**
* Gets the total number of months in this period.
* <p>
* This returns the total number of months in the period by multiplying the
* number of years by 12 and adding the number of months.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @return the total number of months in the period, may be negative
*/
public long
toTotalMonths() {
return
years * 12L +
months; // no overflow
}
//-------------------------------------------------------------------------
/**
* Adds this period to the specified temporal object.
* <p>
* This returns a temporal object of the same observable type as the input
* with this period added.
* If the temporal has a chronology, it must be the ISO chronology.
* <p>
* In most cases, it is clearer to reverse the calling pattern by using
* {@link Temporal#plus(TemporalAmount)}.
* <pre>
* // these two lines are equivalent, but the second approach is recommended
* dateTime = thisPeriod.addTo(dateTime);
* dateTime = dateTime.plus(thisPeriod);
* </pre>
* <p>
* The calculation operates as follows.
* First, the chronology of the temporal is checked to ensure it is ISO chronology or null.
* Second, if the months are zero, the years are added if non-zero, otherwise
* the combination of years and months is added if non-zero.
* Finally, any days are added.
* <p>
* This approach ensures that a partial period can be added to a partial date.
* For example, a period of years and/or months can be added to a {@code YearMonth},
* but a period including days cannot.
* The approach also adds years and months together when necessary, which ensures
* correct behaviour at the end of the month.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param temporal the temporal object to adjust, not null
* @return an object of the same type with the adjustment made, not null
* @throws DateTimeException if unable to add
* @throws ArithmeticException if numeric overflow occurs
*/
@
Override
public
Temporal addTo(
Temporal temporal) {
validateChrono(
temporal);
if (
months == 0) {
if (
years != 0) {
temporal =
temporal.
plus(
years,
YEARS);
}
} else {
long
totalMonths =
toTotalMonths();
if (
totalMonths != 0) {
temporal =
temporal.
plus(
totalMonths,
MONTHS);
}
}
if (
days != 0) {
temporal =
temporal.
plus(
days,
DAYS);
}
return
temporal;
}
/**
* Subtracts this period from the specified temporal object.
* <p>
* This returns a temporal object of the same observable type as the input
* with this period subtracted.
* If the temporal has a chronology, it must be the ISO chronology.
* <p>
* In most cases, it is clearer to reverse the calling pattern by using
* {@link Temporal#minus(TemporalAmount)}.
* <pre>
* // these two lines are equivalent, but the second approach is recommended
* dateTime = thisPeriod.subtractFrom(dateTime);
* dateTime = dateTime.minus(thisPeriod);
* </pre>
* <p>
* The calculation operates as follows.
* First, the chronology of the temporal is checked to ensure it is ISO chronology or null.
* Second, if the months are zero, the years are subtracted if non-zero, otherwise
* the combination of years and months is subtracted if non-zero.
* Finally, any days are subtracted.
* <p>
* This approach ensures that a partial period can be subtracted from a partial date.
* For example, a period of years and/or months can be subtracted from a {@code YearMonth},
* but a period including days cannot.
* The approach also subtracts years and months together when necessary, which ensures
* correct behaviour at the end of the month.
* <p>
* This instance is immutable and unaffected by this method call.
*
* @param temporal the temporal object to adjust, not null
* @return an object of the same type with the adjustment made, not null
* @throws DateTimeException if unable to subtract
* @throws ArithmeticException if numeric overflow occurs
*/
@
Override
public
Temporal subtractFrom(
Temporal temporal) {
validateChrono(
temporal);
if (
months == 0) {
if (
years != 0) {
temporal =
temporal.
minus(
years,
YEARS);
}
} else {
long
totalMonths =
toTotalMonths();
if (
totalMonths != 0) {
temporal =
temporal.
minus(
totalMonths,
MONTHS);
}
}
if (
days != 0) {
temporal =
temporal.
minus(
days,
DAYS);
}
return
temporal;
}
/**
* Validates that the temporal has the correct chronology.
*/
private void
validateChrono(
TemporalAccessor temporal) {
Objects.
requireNonNull(
temporal, "temporal");
Chronology temporalChrono =
temporal.
query(
TemporalQueries.
chronology());
if (
temporalChrono != null &&
IsoChronology.
INSTANCE.
equals(
temporalChrono) == false) {
throw new
DateTimeException("Chronology mismatch, expected: ISO, actual: " +
temporalChrono.
getId());
}
}
//-----------------------------------------------------------------------
/**
* Checks if this period is equal to another period.
* <p>
* The comparison is based on the type {@code Period} and each of the three amounts.
* To be equal, the years, months and days units must be individually equal.
* Note that this means that a period of "15 Months" is not equal to a period
* of "1 Year and 3 Months".
*
* @param obj the object to check, null returns false
* @return true if this is equal to the other period
*/
@
Override
public boolean
equals(
Object obj) {
if (this ==
obj) {
return true;
}
if (
obj instanceof
Period) {
Period other = (
Period)
obj;
return
years ==
other.
years &&
months ==
other.
months &&
days ==
other.
days;
}
return false;
}
/**
* A hash code for this period.
*
* @return a suitable hash code
*/
@
Override
public int
hashCode() {
return
years +
Integer.
rotateLeft(
months, 8) +
Integer.
rotateLeft(
days, 16);
}
//-----------------------------------------------------------------------
/**
* Outputs this period as a {@code String}, such as {@code P6Y3M1D}.
* <p>
* The output will be in the ISO-8601 period format.
* A zero period will be represented as zero days, 'P0D'.
*
* @return a string representation of this period, not null
*/
@
Override
public
String toString() {
if (this ==
ZERO) {
return "P0D";
} else {
StringBuilder buf = new
StringBuilder();
buf.
append('P');
if (
years != 0) {
buf.
append(
years).
append('Y');
}
if (
months != 0) {
buf.
append(
months).
append('M');
}
if (
days != 0) {
buf.
append(
days).
append('D');
}
return
buf.
toString();
}
}
//-----------------------------------------------------------------------
/**
* Writes the object using a
* <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
* @serialData
* <pre>
* out.writeByte(14); // identifies a Period
* out.writeInt(years);
* out.writeInt(months);
* out.writeInt(days);
* </pre>
*
* @return the instance of {@code Ser}, not null
*/
private
Object writeReplace() {
return new
Ser(
Ser.
PERIOD_TYPE, this);
}
/**
* Defend against malicious streams.
*
* @param s the stream to read
* @throws java.io.InvalidObjectException always
*/
private void
readObject(
ObjectInputStream s) throws
InvalidObjectException {
throw new
InvalidObjectException("Deserialization via serialization delegate");
}
void
writeExternal(
DataOutput out) throws
IOException {
out.
writeInt(
years);
out.
writeInt(
months);
out.
writeInt(
days);
}
static
Period readExternal(
DataInput in) throws
IOException {
int
years =
in.
readInt();
int
months =
in.
readInt();
int
days =
in.
readInt();
return
Period.
of(
years,
months,
days);
}
}