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/* * Copyright (c) 2012, 2018, 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.chrono; import static java.time.chrono.ThaiBuddhistChronology.YEARS_DIFFERENCE; import static java.time.temporal.ChronoField.DAY_OF_MONTH; import static java.time.temporal.ChronoField.MONTH_OF_YEAR; 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.Clock; import java.time.DateTimeException; import java.time.LocalDate; import java.time.LocalTime; import java.time.Period; import java.time.ZoneId; import java.time.temporal.ChronoField; import java.time.temporal.TemporalAccessor; import java.time.temporal.TemporalAdjuster; import java.time.temporal.TemporalAmount; import java.time.temporal.TemporalField; import java.time.temporal.TemporalQuery; import java.time.temporal.TemporalUnit; import java.time.temporal.UnsupportedTemporalTypeException; import java.time.temporal.ValueRange; import java.util.Objects; /** * A date in the Thai Buddhist calendar system. * <p> * This date operates using the {@linkplain ThaiBuddhistChronology Thai Buddhist calendar}. * This calendar system is primarily used in Thailand. * Dates are aligned such that {@code 2484-01-01 (Buddhist)} is {@code 1941-01-01 (ISO)}. * * <p> * This is a <a href="{@docRoot}/java.base/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 ThaiBuddhistDate} 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 ThaiBuddhistDate extends ChronoLocalDateImpl<ThaiBuddhistDate> implements ChronoLocalDate, Serializable { /** * Serialization version. */ private static final long serialVersionUID = -8722293800195731463L; /** * The underlying date. */ private final transient LocalDate isoDate; //----------------------------------------------------------------------- /** * Obtains the current {@code ThaiBuddhistDate} 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 ThaiBuddhistDate now() { return now(Clock.systemDefaultZone()); } /** * Obtains the current {@code ThaiBuddhistDate} 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 ThaiBuddhistDate now(ZoneId zone) { return now(Clock.system(zone)); } /** * Obtains the current {@code ThaiBuddhistDate} 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 {@linkplain Clock dependency injection}. * * @param clock the clock to use, not null * @return the current date, not null * @throws DateTimeException if the current date cannot be obtained */ public static ThaiBuddhistDate now(Clock clock) { return new ThaiBuddhistDate(LocalDate.now(clock)); } /** * Obtains a {@code ThaiBuddhistDate} representing a date in the Thai Buddhist calendar * system from the proleptic-year, month-of-year and day-of-month fields. * <p> * This returns a {@code ThaiBuddhistDate} with the specified fields. * The day must be valid for the year and month, otherwise an exception will be thrown. * * @param prolepticYear the Thai Buddhist proleptic-year * @param month the Thai Buddhist month-of-year, from 1 to 12 * @param dayOfMonth the Thai Buddhist day-of-month, from 1 to 31 * @return the date in Thai Buddhist calendar system, 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 ThaiBuddhistDate of(int prolepticYear, int month, int dayOfMonth) { return new ThaiBuddhistDate(LocalDate.of(prolepticYear - YEARS_DIFFERENCE, month, dayOfMonth)); } /** * Obtains a {@code ThaiBuddhistDate} from a temporal object. * <p> * This obtains a date in the Thai Buddhist calendar system 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 ThaiBuddhistDate}. * <p> * The conversion typically uses the {@link ChronoField#EPOCH_DAY EPOCH_DAY} * field, which is standardized across calendar systems. * <p> * This method matches the signature of the functional interface {@link TemporalQuery} * allowing it to be used as a query via method reference, {@code ThaiBuddhistDate::from}. * * @param temporal the temporal object to convert, not null * @return the date in Thai Buddhist calendar system, not null * @throws DateTimeException if unable to convert to a {@code ThaiBuddhistDate} */ public static ThaiBuddhistDate from(TemporalAccessor temporal) { return ThaiBuddhistChronology.INSTANCE.date(temporal); } //----------------------------------------------------------------------- /** * Creates an instance from an ISO date. * * @param isoDate the standard local date, validated not null */ ThaiBuddhistDate(LocalDate isoDate) { Objects.requireNonNull(isoDate, "isoDate"); this.isoDate = isoDate; } //----------------------------------------------------------------------- /** * Gets the chronology of this date, which is the Thai Buddhist calendar system. * <p> * The {@code Chronology} represents the calendar system in use. * The era and other fields in {@link ChronoField} are defined by the chronology. * * @return the Thai Buddhist chronology, not null */ @Override public ThaiBuddhistChronology getChronology() { return ThaiBuddhistChronology.INSTANCE; } /** * Gets the era applicable at this date. * <p> * The Thai Buddhist calendar system has two eras, 'BE' and 'BEFORE_BE', * defined by {@link ThaiBuddhistEra}. * * @return the era applicable at this date, not null */ @Override public ThaiBuddhistEra getEra() { return (getProlepticYear() >= 1 ? ThaiBuddhistEra.BE : ThaiBuddhistEra.BEFORE_BE); } /** * Returns the length of the month represented by this date. * <p> * This returns the length of the month in days. * Month lengths match those of the ISO calendar system. * * @return the length of the month in days */ @Override public int lengthOfMonth() { return isoDate.lengthOfMonth(); } //----------------------------------------------------------------------- @Override public ValueRange range(TemporalField field) { if (field instanceof ChronoField) { if (isSupported(field)) { ChronoField f = (ChronoField) field; switch (f) { case DAY_OF_MONTH: case DAY_OF_YEAR: case ALIGNED_WEEK_OF_MONTH: return isoDate.range(field); case YEAR_OF_ERA: { ValueRange range = YEAR.range(); long max = (getProlepticYear() <= 0 ? -(range.getMinimum() + YEARS_DIFFERENCE) + 1 : range.getMaximum() + YEARS_DIFFERENCE); return ValueRange.of(1, max); } } return getChronology().range(f); } throw new UnsupportedTemporalTypeException("Unsupported field: " + field); } return field.rangeRefinedBy(this); } @Override public long getLong(TemporalField field) { if (field instanceof ChronoField) { switch ((ChronoField) field) { case PROLEPTIC_MONTH: return getProlepticMonth(); case YEAR_OF_ERA: { int prolepticYear = getProlepticYear(); return (prolepticYear >= 1 ? prolepticYear : 1 - prolepticYear); } case YEAR: return getProlepticYear(); case ERA: return (getProlepticYear() >= 1 ? 1 : 0); } return isoDate.getLong(field); } return field.getFrom(this); } private long getProlepticMonth() { return getProlepticYear() * 12L + isoDate.getMonthValue() - 1; } private int getProlepticYear() { return isoDate.getYear() + YEARS_DIFFERENCE; } //----------------------------------------------------------------------- @Override public ThaiBuddhistDate with(TemporalField field, long newValue) { if (field instanceof ChronoField) { ChronoField f = (ChronoField) field; if (getLong(f) == newValue) { return this; } switch (f) { case PROLEPTIC_MONTH: getChronology().range(f).checkValidValue(newValue, f); return plusMonths(newValue - getProlepticMonth()); case YEAR_OF_ERA: case YEAR: case ERA: { int nvalue = getChronology().range(f).checkValidIntValue(newValue, f); switch (f) { case YEAR_OF_ERA: return with( isoDate.withYear((getProlepticYear() >= 1 ? nvalue : 1 - nvalue) - YEARS_DIFFERENCE)); case YEAR: return with(isoDate.withYear(nvalue - YEARS_DIFFERENCE)); case ERA: return with(isoDate.withYear((1 - getProlepticYear()) - YEARS_DIFFERENCE)); } } } return with(isoDate.with(field, newValue)); } return super.with(field, newValue); } /** * {@inheritDoc} * @throws DateTimeException {@inheritDoc} * @throws ArithmeticException {@inheritDoc} */ @Override public ThaiBuddhistDate with(TemporalAdjuster adjuster) { return super.with(adjuster); } /** * {@inheritDoc} * @throws DateTimeException {@inheritDoc} * @throws ArithmeticException {@inheritDoc} */ @Override public ThaiBuddhistDate plus(TemporalAmount amount) { return super.plus(amount); } /** * {@inheritDoc} * @throws DateTimeException {@inheritDoc} * @throws ArithmeticException {@inheritDoc} */ @Override public ThaiBuddhistDate minus(TemporalAmount amount) { return super.minus(amount); } //----------------------------------------------------------------------- @Override ThaiBuddhistDate plusYears(long years) { return with(isoDate.plusYears(years)); } @Override ThaiBuddhistDate plusMonths(long months) { return with(isoDate.plusMonths(months)); } @Override ThaiBuddhistDate plusWeeks(long weeksToAdd) { return super.plusWeeks(weeksToAdd); } @Override ThaiBuddhistDate plusDays(long days) { return with(isoDate.plusDays(days)); } @Override public ThaiBuddhistDate plus(long amountToAdd, TemporalUnit unit) { return super.plus(amountToAdd, unit); } @Override public ThaiBuddhistDate minus(long amountToAdd, TemporalUnit unit) { return super.minus(amountToAdd, unit); } @Override ThaiBuddhistDate minusYears(long yearsToSubtract) { return super.minusYears(yearsToSubtract); } @Override ThaiBuddhistDate minusMonths(long monthsToSubtract) { return super.minusMonths(monthsToSubtract); } @Override ThaiBuddhistDate minusWeeks(long weeksToSubtract) { return super.minusWeeks(weeksToSubtract); } @Override ThaiBuddhistDate minusDays(long daysToSubtract) { return super.minusDays(daysToSubtract); } private ThaiBuddhistDate with(LocalDate newDate) { return (newDate.equals(isoDate) ? this : new ThaiBuddhistDate(newDate)); } @Override // for javadoc and covariant return type @SuppressWarnings("unchecked") public final ChronoLocalDateTime<ThaiBuddhistDate> atTime(LocalTime localTime) { return (ChronoLocalDateTime<ThaiBuddhistDate>) super.atTime(localTime); } @Override public ChronoPeriod until(ChronoLocalDate endDate) { Period period = isoDate.until(endDate); return getChronology().period(period.getYears(), period.getMonths(), period.getDays()); } @Override // override for performance public long toEpochDay() { return isoDate.toEpochDay(); } //------------------------------------------------------------------------- /** * Compares this date to another date, including the chronology. * <p> * Compares this {@code ThaiBuddhistDate} with another ensuring that the date is the same. * <p> * Only objects of type {@code ThaiBuddhistDate} are compared, other types return false. * To compare the dates of two {@code TemporalAccessor} instances, including dates * in two different chronologies, use {@link ChronoField#EPOCH_DAY} as a comparator. * * @param obj the object to check, null returns false * @return true if this is equal to the other date */ @Override // override for performance public boolean equals(Object obj) { if (this == obj) { return true; } if (obj instanceof ThaiBuddhistDate) { ThaiBuddhistDate otherDate = (ThaiBuddhistDate) obj; return this.isoDate.equals(otherDate.isoDate); } return false; } /** * A hash code for this date. * * @return a suitable hash code based only on the Chronology and the date */ @Override // override for performance public int hashCode() { return getChronology().getId().hashCode() ^ isoDate.hashCode(); } //----------------------------------------------------------------------- /** * Defend against malicious streams. * * @param s the stream to read * @throws InvalidObjectException always */ private void readObject(ObjectInputStream s) throws InvalidObjectException { throw new InvalidObjectException("Deserialization via serialization delegate"); } /** * Writes the object using a * <a href="{@docRoot}/serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>. * @serialData * <pre> * out.writeByte(10); // identifies a ThaiBuddhistDate * out.writeInt(get(YEAR)); * out.writeByte(get(MONTH_OF_YEAR)); * out.writeByte(get(DAY_OF_MONTH)); * </pre> * * @return the instance of {@code Ser}, not null */ private Object writeReplace() { return new Ser(Ser.THAIBUDDHIST_DATE_TYPE, this); } void writeExternal(DataOutput out) throws IOException { // ThaiBuddhistChronology is implicit in the THAIBUDDHIST_DATE_TYPE out.writeInt(this.get(YEAR)); out.writeByte(this.get(MONTH_OF_YEAR)); out.writeByte(this.get(DAY_OF_MONTH)); } static ThaiBuddhistDate readExternal(DataInput in) throws IOException { int year = in.readInt(); int month = in.readByte(); int dayOfMonth = in.readByte(); return ThaiBuddhistChronology.INSTANCE.date(year, month, dayOfMonth); } }