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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. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* * 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; } }