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* Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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*
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*
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/*
* Copyright (c) 2012, Stephen Colebourne & Michael Nascimento Santos
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* * Neither the name of JSR-310 nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package java.time.temporal;
import java.time.Duration;
/**
* A standard set of date periods units.
* <p>
* This set of units provide unit-based access to manipulate a date, time or date-time.
* The standard set of units can be extended by implementing {@link TemporalUnit}.
* <p>
* These units are intended to be applicable in multiple calendar systems.
* For example, most non-ISO calendar systems define units of years, months and days,
* just with slightly different rules.
* The documentation of each unit explains how it operates.
*
* @implSpec
* This is a final, immutable and thread-safe enum.
*
* @since 1.8
*/
public enum ChronoUnit implements TemporalUnit {
/**
* Unit that represents the concept of a nanosecond, the smallest supported unit of time.
* For the ISO calendar system, it is equal to the 1,000,000,000th part of the second unit.
*/
NANOS("Nanos", Duration.ofNanos(1)),
/**
* Unit that represents the concept of a microsecond.
* For the ISO calendar system, it is equal to the 1,000,000th part of the second unit.
*/
MICROS("Micros", Duration.ofNanos(1000)),
/**
* Unit that represents the concept of a millisecond.
* For the ISO calendar system, it is equal to the 1000th part of the second unit.
*/
MILLIS("Millis", Duration.ofNanos(1000_000)),
/**
* Unit that represents the concept of a second.
* For the ISO calendar system, it is equal to the second in the SI system
* of units, except around a leap-second.
*/
SECONDS("Seconds", Duration.ofSeconds(1)),
/**
* Unit that represents the concept of a minute.
* For the ISO calendar system, it is equal to 60 seconds.
*/
MINUTES("Minutes", Duration.ofSeconds(60)),
/**
* Unit that represents the concept of an hour.
* For the ISO calendar system, it is equal to 60 minutes.
*/
HOURS("Hours", Duration.ofSeconds(3600)),
/**
* Unit that represents the concept of half a day, as used in AM/PM.
* For the ISO calendar system, it is equal to 12 hours.
*/
HALF_DAYS("HalfDays", Duration.ofSeconds(43200)),
/**
* Unit that represents the concept of a day.
* For the ISO calendar system, it is the standard day from midnight to midnight.
* The estimated duration of a day is {@code 24 Hours}.
* <p>
* When used with other calendar systems it must correspond to the day defined by
* the rising and setting of the Sun on Earth. It is not required that days begin
* at midnight - when converting between calendar systems, the date should be
* equivalent at midday.
*/
DAYS("Days", Duration.ofSeconds(86400)),
/**
* Unit that represents the concept of a week.
* For the ISO calendar system, it is equal to 7 days.
* <p>
* When used with other calendar systems it must correspond to an integral number of days.
*/
WEEKS("Weeks", Duration.ofSeconds(7 * 86400L)),
/**
* Unit that represents the concept of a month.
* For the ISO calendar system, the length of the month varies by month-of-year.
* The estimated duration of a month is one twelfth of {@code 365.2425 Days}.
* <p>
* When used with other calendar systems it must correspond to an integral number of days.
*/
MONTHS("Months", Duration.ofSeconds(31556952L / 12)),
/**
* Unit that represents the concept of a year.
* For the ISO calendar system, it is equal to 12 months.
* The estimated duration of a year is {@code 365.2425 Days}.
* <p>
* When used with other calendar systems it must correspond to an integral number of days
* or months roughly equal to a year defined by the passage of the Earth around the Sun.
*/
YEARS("Years", Duration.ofSeconds(31556952L)),
/**
* Unit that represents the concept of a decade.
* For the ISO calendar system, it is equal to 10 years.
* <p>
* When used with other calendar systems it must correspond to an integral number of days
* and is normally an integral number of years.
*/
DECADES("Decades", Duration.ofSeconds(31556952L * 10L)),
/**
* Unit that represents the concept of a century.
* For the ISO calendar system, it is equal to 100 years.
* <p>
* When used with other calendar systems it must correspond to an integral number of days
* and is normally an integral number of years.
*/
CENTURIES("Centuries", Duration.ofSeconds(31556952L * 100L)),
/**
* Unit that represents the concept of a millennium.
* For the ISO calendar system, it is equal to 1000 years.
* <p>
* When used with other calendar systems it must correspond to an integral number of days
* and is normally an integral number of years.
*/
MILLENNIA("Millennia", Duration.ofSeconds(31556952L * 1000L)),
/**
* Unit that represents the concept of an era.
* The ISO calendar system doesn't have eras thus it is impossible to add
* an era to a date or date-time.
* The estimated duration of the era is artificially defined as {@code 1,000,000,000 Years}.
* <p>
* When used with other calendar systems there are no restrictions on the unit.
*/
ERAS("Eras", Duration.ofSeconds(31556952L * 1000_000_000L)),
/**
* Artificial unit that represents the concept of forever.
* This is primarily used with {@link TemporalField} to represent unbounded fields
* such as the year or era.
* The estimated duration of this unit is artificially defined as the largest duration
* supported by {@link Duration}.
*/
FOREVER("Forever", Duration.ofSeconds(Long.MAX_VALUE, 999_999_999));
private final String name;
private final Duration duration;
private ChronoUnit(String name, Duration estimatedDuration) {
this.name = name;
this.duration = estimatedDuration;
}
//-----------------------------------------------------------------------
/**
* Gets the estimated duration of this unit in the ISO calendar system.
* <p>
* All of the units in this class have an estimated duration.
* Days vary due to daylight saving time, while months have different lengths.
*
* @return the estimated duration of this unit, not null
*/
@Override
public Duration getDuration() {
return duration;
}
/**
* Checks if the duration of the unit is an estimate.
* <p>
* All time units in this class are considered to be accurate, while all date
* units in this class are considered to be estimated.
* <p>
* This definition ignores leap seconds, but considers that Days vary due to
* daylight saving time and months have different lengths.
*
* @return true if the duration is estimated, false if accurate
*/
@Override
public boolean isDurationEstimated() {
return this.compareTo(DAYS) >= 0;
}
//-----------------------------------------------------------------------
/**
* Checks if this unit is a date unit.
* <p>
* All units from days to eras inclusive are date-based.
* Time-based units and {@code FOREVER} return false.
*
* @return true if a date unit, false if a time unit
*/
@Override
public boolean isDateBased() {
return this.compareTo(DAYS) >= 0 && this != FOREVER;
}
/**
* Checks if this unit is a time unit.
* <p>
* All units from nanos to half-days inclusive are time-based.
* Date-based units and {@code FOREVER} return false.
*
* @return true if a time unit, false if a date unit
*/
@Override
public boolean isTimeBased() {
return this.compareTo(DAYS) < 0;
}
//-----------------------------------------------------------------------
@Override
public boolean isSupportedBy(Temporal temporal) {
return temporal.isSupported(this);
}
@SuppressWarnings("unchecked")
@Override
public <R extends Temporal> R addTo(R temporal, long amount) {
return (R) temporal.plus(amount, this);
}
//-----------------------------------------------------------------------
@Override
public long between(Temporal temporal1Inclusive, Temporal temporal2Exclusive) {
return temporal1Inclusive.until(temporal2Exclusive, this);
}
//-----------------------------------------------------------------------
@Override
public String toString() {
return name;
}
}