/* * 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. */ /* * 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) 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.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_WEEK; 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 static java.time.temporal.ChronoField.YEAR_OF_ERA; import static java.time.temporal.ChronoUnit.DAYS; import static java.time.temporal.ChronoUnit.MONTHS; import static java.time.temporal.ChronoUnit.WEEKS; import static java.time.temporal.TemporalAdjusters.nextOrSame; import java.io.DataInput; import java.io.DataOutput; import java.io.IOException; import java.io.InvalidObjectException; import java.io.ObjectInputStream; import java.io.ObjectStreamException; import java.io.Serializable; import java.time.DateTimeException; import java.time.DayOfWeek; import java.time.format.ResolverStyle; import java.time.temporal.ChronoField; import java.time.temporal.TemporalAdjusters; import java.time.temporal.TemporalField; import java.time.temporal.ValueRange; import java.util.Comparator; import java.util.HashSet; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Objects; import java.util.ServiceLoader; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; import sun.util.logging.PlatformLogger; /** * An abstract implementation of a calendar system, used to organize and identify dates. *

* The main date and time API is built on the ISO calendar system. * The chronology operates behind the scenes to represent the general concept of a calendar system. *

* See {@link Chronology} for more details. * * @implSpec * This class is separated from the {@code Chronology} interface so that the static methods * are not inherited. While {@code Chronology} can be implemented directly, it is strongly * recommended to extend this abstract class instead. *

* This class must be implemented with care to ensure other classes operate correctly. * All implementations that can be instantiated must be final, immutable and thread-safe. * Subclasses should be Serializable wherever possible. * * @since 1.8 */ public abstract class AbstractChronology implements Chronology { /** * Map of available calendars by ID. */ private static final ConcurrentHashMap CHRONOS_BY_ID = new ConcurrentHashMap<>(); /** * Map of available calendars by calendar type. */ private static final ConcurrentHashMap CHRONOS_BY_TYPE = new ConcurrentHashMap<>(); /** * Register a Chronology by its ID and type for lookup by {@link #of(String)}. * Chronologies must not be registered until they are completely constructed. * Specifically, not in the constructor of Chronology. * * @param chrono the chronology to register; not null * @return the already registered Chronology if any, may be null */ static Chronology registerChrono(Chronology chrono) { return registerChrono(chrono, chrono.getId()); } /** * Register a Chronology by ID and type for lookup by {@link #of(String)}. * Chronos must not be registered until they are completely constructed. * Specifically, not in the constructor of Chronology. * * @param chrono the chronology to register; not null * @param id the ID to register the chronology; not null * @return the already registered Chronology if any, may be null */ static Chronology registerChrono(Chronology chrono, String id) { Chronology prev = CHRONOS_BY_ID.putIfAbsent(id, chrono); if (prev == null) { String type = chrono.getCalendarType(); if (type != null) { CHRONOS_BY_TYPE.putIfAbsent(type, chrono); } } return prev; } /** * Initialization of the maps from id and type to Chronology. * The ServiceLoader is used to find and register any implementations * of {@link java.time.chrono.AbstractChronology} found in the bootclass loader. * The built-in chronologies are registered explicitly. * Calendars configured via the Thread's context classloader are local * to that thread and are ignored. *

* The initialization is done only once using the registration * of the IsoChronology as the test and the final step. * Multiple threads may perform the initialization concurrently. * Only the first registration of each Chronology is retained by the * ConcurrentHashMap. * @return true if the cache was initialized */ private static boolean initCache() { if (CHRONOS_BY_ID.get("ISO") == null) { // Initialization is incomplete // Register built-in Chronologies registerChrono(HijrahChronology.INSTANCE); registerChrono(JapaneseChronology.INSTANCE); registerChrono(MinguoChronology.INSTANCE); registerChrono(ThaiBuddhistChronology.INSTANCE); // Register Chronologies from the ServiceLoader @SuppressWarnings("rawtypes") ServiceLoader loader = ServiceLoader.load(AbstractChronology.class, null); for (AbstractChronology chrono : loader) { String id = chrono.getId(); if (id.equals("ISO") || registerChrono(chrono) != null) { // Log the attempt to replace an existing Chronology PlatformLogger logger = PlatformLogger.getLogger("java.time.chrono"); logger.warning("Ignoring duplicate Chronology, from ServiceLoader configuration " + id); } } // finally, register IsoChronology to mark initialization is complete registerChrono(IsoChronology.INSTANCE); return true; } return false; } //----------------------------------------------------------------------- /** * Obtains an instance of {@code Chronology} from a locale. *

* See {@link Chronology#ofLocale(Locale)}. * * @param locale the locale to use to obtain the calendar system, not null * @return the calendar system associated with the locale, not null * @throws java.time.DateTimeException if the locale-specified calendar cannot be found */ static Chronology ofLocale(Locale locale) { Objects.requireNonNull(locale, "locale"); String type = locale.getUnicodeLocaleType("ca"); if (type == null || "iso".equals(type) || "iso8601".equals(type)) { return IsoChronology.INSTANCE; } // Not pre-defined; lookup by the type do { Chronology chrono = CHRONOS_BY_TYPE.get(type); if (chrono != null) { return chrono; } // If not found, do the initialization (once) and repeat the lookup } while (initCache()); // Look for a Chronology using ServiceLoader of the Thread's ContextClassLoader // Application provided Chronologies must not be cached @SuppressWarnings("rawtypes") ServiceLoader loader = ServiceLoader.load(Chronology.class); for (Chronology chrono : loader) { if (type.equals(chrono.getCalendarType())) { return chrono; } } throw new DateTimeException("Unknown calendar system: " + type); } //----------------------------------------------------------------------- /** * Obtains an instance of {@code Chronology} from a chronology ID or * calendar system type. *

* See {@link Chronology#of(String)}. * * @param id the chronology ID or calendar system type, not null * @return the chronology with the identifier requested, not null * @throws java.time.DateTimeException if the chronology cannot be found */ static Chronology of(String id) { Objects.requireNonNull(id, "id"); do { Chronology chrono = of0(id); if (chrono != null) { return chrono; } // If not found, do the initialization (once) and repeat the lookup } while (initCache()); // Look for a Chronology using ServiceLoader of the Thread's ContextClassLoader // Application provided Chronologies must not be cached @SuppressWarnings("rawtypes") ServiceLoader loader = ServiceLoader.load(Chronology.class); for (Chronology chrono : loader) { if (id.equals(chrono.getId()) || id.equals(chrono.getCalendarType())) { return chrono; } } throw new DateTimeException("Unknown chronology: " + id); } /** * Obtains an instance of {@code Chronology} from a chronology ID or * calendar system type. * * @param id the chronology ID or calendar system type, not null * @return the chronology with the identifier requested, or {@code null} if not found */ private static Chronology of0(String id) { Chronology chrono = CHRONOS_BY_ID.get(id); if (chrono == null) { chrono = CHRONOS_BY_TYPE.get(id); } return chrono; } /** * Returns the available chronologies. *

* Each returned {@code Chronology} is available for use in the system. * The set of chronologies includes the system chronologies and * any chronologies provided by the application via ServiceLoader * configuration. * * @return the independent, modifiable set of the available chronology IDs, not null */ static Set getAvailableChronologies() { initCache(); // force initialization HashSet chronos = new HashSet<>(CHRONOS_BY_ID.values()); /// Add in Chronologies from the ServiceLoader configuration @SuppressWarnings("rawtypes") ServiceLoader loader = ServiceLoader.load(Chronology.class); for (Chronology chrono : loader) { chronos.add(chrono); } return chronos; } //----------------------------------------------------------------------- /** * Creates an instance. */ protected AbstractChronology() { } //----------------------------------------------------------------------- /** * Resolves parsed {@code ChronoField} values into a date during parsing. *

* Most {@code TemporalField} implementations are resolved using the * resolve method on the field. By contrast, the {@code ChronoField} class * defines fields that only have meaning relative to the chronology. * As such, {@code ChronoField} date fields are resolved here in the * context of a specific chronology. *

* {@code ChronoField} instances are resolved by this method, which may * be overridden in subclasses. *

*

* The default implementation is suitable for most calendar systems. * If {@link java.time.temporal.ChronoField#YEAR_OF_ERA} is found without an {@link java.time.temporal.ChronoField#ERA} * then the last era in {@link #eras()} is used. * The implementation assumes a 7 day week, that the first day-of-month * has the value 1, that first day-of-year has the value 1, and that the * first of the month and year always exists. * * @param fieldValues the map of fields to values, which can be updated, not null * @param resolverStyle the requested type of resolve, not null * @return the resolved date, null if insufficient information to create a date * @throws java.time.DateTimeException if the date cannot be resolved, typically * because of a conflict in the input data */ @Override public ChronoLocalDate resolveDate(Map fieldValues, ResolverStyle resolverStyle) { // check epoch-day before inventing era if (fieldValues.containsKey(EPOCH_DAY)) { return dateEpochDay(fieldValues.remove(EPOCH_DAY)); } // fix proleptic month before inventing era resolveProlepticMonth(fieldValues, resolverStyle); // invent era if necessary to resolve year-of-era ChronoLocalDate resolved = resolveYearOfEra(fieldValues, resolverStyle); if (resolved != null) { return resolved; } // build date if (fieldValues.containsKey(YEAR)) { if (fieldValues.containsKey(MONTH_OF_YEAR)) { if (fieldValues.containsKey(DAY_OF_MONTH)) { return resolveYMD(fieldValues, resolverStyle); } if (fieldValues.containsKey(ALIGNED_WEEK_OF_MONTH)) { if (fieldValues.containsKey(ALIGNED_DAY_OF_WEEK_IN_MONTH)) { return resolveYMAA(fieldValues, resolverStyle); } if (fieldValues.containsKey(DAY_OF_WEEK)) { return resolveYMAD(fieldValues, resolverStyle); } } } if (fieldValues.containsKey(DAY_OF_YEAR)) { return resolveYD(fieldValues, resolverStyle); } if (fieldValues.containsKey(ALIGNED_WEEK_OF_YEAR)) { if (fieldValues.containsKey(ALIGNED_DAY_OF_WEEK_IN_YEAR)) { return resolveYAA(fieldValues, resolverStyle); } if (fieldValues.containsKey(DAY_OF_WEEK)) { return resolveYAD(fieldValues, resolverStyle); } } } return null; } void resolveProlepticMonth(Map fieldValues, ResolverStyle resolverStyle) { Long pMonth = fieldValues.remove(PROLEPTIC_MONTH); if (pMonth != null) { if (resolverStyle != ResolverStyle.LENIENT) { PROLEPTIC_MONTH.checkValidValue(pMonth); } // first day-of-month is likely to be safest for setting proleptic-month // cannot add to year zero, as not all chronologies have a year zero ChronoLocalDate chronoDate = dateNow() .with(DAY_OF_MONTH, 1).with(PROLEPTIC_MONTH, pMonth); addFieldValue(fieldValues, MONTH_OF_YEAR, chronoDate.get(MONTH_OF_YEAR)); addFieldValue(fieldValues, YEAR, chronoDate.get(YEAR)); } } ChronoLocalDate resolveYearOfEra(Map fieldValues, ResolverStyle resolverStyle) { Long yoeLong = fieldValues.remove(YEAR_OF_ERA); if (yoeLong != null) { Long eraLong = fieldValues.remove(ERA); int yoe; if (resolverStyle != ResolverStyle.LENIENT) { yoe = range(YEAR_OF_ERA).checkValidIntValue(yoeLong, YEAR_OF_ERA); } else { yoe = Math.toIntExact(yoeLong); } if (eraLong != null) { Era eraObj = eraOf(range(ERA).checkValidIntValue(eraLong, ERA)); addFieldValue(fieldValues, YEAR, prolepticYear(eraObj, yoe)); } else { if (fieldValues.containsKey(YEAR)) { int year = range(YEAR).checkValidIntValue(fieldValues.get(YEAR), YEAR); ChronoLocalDate chronoDate = dateYearDay(year, 1); addFieldValue(fieldValues, YEAR, prolepticYear(chronoDate.getEra(), yoe)); } else if (resolverStyle == ResolverStyle.STRICT) { // do not invent era if strict // reinstate the field removed earlier, no cross-check issues fieldValues.put(YEAR_OF_ERA, yoeLong); } else { List eras = eras(); if (eras.isEmpty()) { addFieldValue(fieldValues, YEAR, yoe); } else { Era eraObj = eras.get(eras.size() - 1); addFieldValue(fieldValues, YEAR, prolepticYear(eraObj, yoe)); } } } } else if (fieldValues.containsKey(ERA)) { range(ERA).checkValidValue(fieldValues.get(ERA), ERA); // always validated } return null; } ChronoLocalDate resolveYMD(Map fieldValues, ResolverStyle resolverStyle) { int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR); if (resolverStyle == ResolverStyle.LENIENT) { long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1); long days = Math.subtractExact(fieldValues.remove(DAY_OF_MONTH), 1); return date(y, 1, 1).plus(months, MONTHS).plus(days, DAYS); } int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR); ValueRange domRange = range(DAY_OF_MONTH); int dom = domRange.checkValidIntValue(fieldValues.remove(DAY_OF_MONTH), DAY_OF_MONTH); if (resolverStyle == ResolverStyle.SMART) { // previous valid try { return date(y, moy, dom); } catch (DateTimeException ex) { return date(y, moy, 1).with(TemporalAdjusters.lastDayOfMonth()); } } return date(y, moy, dom); } ChronoLocalDate resolveYD(Map fieldValues, ResolverStyle resolverStyle) { int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR); if (resolverStyle == ResolverStyle.LENIENT) { long days = Math.subtractExact(fieldValues.remove(DAY_OF_YEAR), 1); return dateYearDay(y, 1).plus(days, DAYS); } int doy = range(DAY_OF_YEAR).checkValidIntValue(fieldValues.remove(DAY_OF_YEAR), DAY_OF_YEAR); return dateYearDay(y, doy); // smart is same as strict } ChronoLocalDate resolveYMAA(Map fieldValues, ResolverStyle resolverStyle) { int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR); if (resolverStyle == ResolverStyle.LENIENT) { long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1); long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), 1); long days = Math.subtractExact(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_MONTH), 1); return date(y, 1, 1).plus(months, MONTHS).plus(weeks, WEEKS).plus(days, DAYS); } int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR); int aw = range(ALIGNED_WEEK_OF_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), ALIGNED_WEEK_OF_MONTH); int ad = range(ALIGNED_DAY_OF_WEEK_IN_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_MONTH), ALIGNED_DAY_OF_WEEK_IN_MONTH); ChronoLocalDate date = date(y, moy, 1).plus((aw - 1) * 7 + (ad - 1), DAYS); if (resolverStyle == ResolverStyle.STRICT && date.get(MONTH_OF_YEAR) != moy) { throw new DateTimeException("Strict mode rejected resolved date as it is in a different month"); } return date; } ChronoLocalDate resolveYMAD(Map fieldValues, ResolverStyle resolverStyle) { int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR); if (resolverStyle == ResolverStyle.LENIENT) { long months = Math.subtractExact(fieldValues.remove(MONTH_OF_YEAR), 1); long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), 1); long dow = Math.subtractExact(fieldValues.remove(DAY_OF_WEEK), 1); return resolveAligned(date(y, 1, 1), months, weeks, dow); } int moy = range(MONTH_OF_YEAR).checkValidIntValue(fieldValues.remove(MONTH_OF_YEAR), MONTH_OF_YEAR); int aw = range(ALIGNED_WEEK_OF_MONTH).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_MONTH), ALIGNED_WEEK_OF_MONTH); int dow = range(DAY_OF_WEEK).checkValidIntValue(fieldValues.remove(DAY_OF_WEEK), DAY_OF_WEEK); ChronoLocalDate date = date(y, moy, 1).plus((aw - 1) * 7, DAYS).with(nextOrSame(DayOfWeek.of(dow))); if (resolverStyle == ResolverStyle.STRICT && date.get(MONTH_OF_YEAR) != moy) { throw new DateTimeException("Strict mode rejected resolved date as it is in a different month"); } return date; } ChronoLocalDate resolveYAA(Map fieldValues, ResolverStyle resolverStyle) { int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR); if (resolverStyle == ResolverStyle.LENIENT) { long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), 1); long days = Math.subtractExact(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_YEAR), 1); return dateYearDay(y, 1).plus(weeks, WEEKS).plus(days, DAYS); } int aw = range(ALIGNED_WEEK_OF_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), ALIGNED_WEEK_OF_YEAR); int ad = range(ALIGNED_DAY_OF_WEEK_IN_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_DAY_OF_WEEK_IN_YEAR), ALIGNED_DAY_OF_WEEK_IN_YEAR); ChronoLocalDate date = dateYearDay(y, 1).plus((aw - 1) * 7 + (ad - 1), DAYS); if (resolverStyle == ResolverStyle.STRICT && date.get(YEAR) != y) { throw new DateTimeException("Strict mode rejected resolved date as it is in a different year"); } return date; } ChronoLocalDate resolveYAD(Map fieldValues, ResolverStyle resolverStyle) { int y = range(YEAR).checkValidIntValue(fieldValues.remove(YEAR), YEAR); if (resolverStyle == ResolverStyle.LENIENT) { long weeks = Math.subtractExact(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), 1); long dow = Math.subtractExact(fieldValues.remove(DAY_OF_WEEK), 1); return resolveAligned(dateYearDay(y, 1), 0, weeks, dow); } int aw = range(ALIGNED_WEEK_OF_YEAR).checkValidIntValue(fieldValues.remove(ALIGNED_WEEK_OF_YEAR), ALIGNED_WEEK_OF_YEAR); int dow = range(DAY_OF_WEEK).checkValidIntValue(fieldValues.remove(DAY_OF_WEEK), DAY_OF_WEEK); ChronoLocalDate date = dateYearDay(y, 1).plus((aw - 1) * 7, DAYS).with(nextOrSame(DayOfWeek.of(dow))); if (resolverStyle == ResolverStyle.STRICT && date.get(YEAR) != y) { throw new DateTimeException("Strict mode rejected resolved date as it is in a different year"); } return date; } ChronoLocalDate resolveAligned(ChronoLocalDate base, long months, long weeks, long dow) { ChronoLocalDate date = base.plus(months, MONTHS).plus(weeks, WEEKS); if (dow > 7) { date = date.plus((dow - 1) / 7, WEEKS); dow = ((dow - 1) % 7) + 1; } else if (dow < 1) { date = date.plus(Math.subtractExact(dow, 7) / 7, WEEKS); dow = ((dow + 6) % 7) + 1; } return date.with(nextOrSame(DayOfWeek.of((int) dow))); } /** * Adds a field-value pair to the map, checking for conflicts. *

* If the field is not already present, then the field-value pair is added to the map. * If the field is already present and it has the same value as that specified, no action occurs. * If the field is already present and it has a different value to that specified, then * an exception is thrown. * * @param field the field to add, not null * @param value the value to add, not null * @throws java.time.DateTimeException if the field is already present with a different value */ void addFieldValue(Map fieldValues, ChronoField field, long value) { Long old = fieldValues.get(field); // check first for better error message if (old != null && old.longValue() != value) { throw new DateTimeException("Conflict found: " + field + " " + old + " differs from " + field + " " + value); } fieldValues.put(field, value); } //----------------------------------------------------------------------- /** * Compares this chronology to another chronology. *

* The comparison order first by the chronology ID string, then by any * additional information specific to the subclass. * It is "consistent with equals", as defined by {@link Comparable}. * * @implSpec * This implementation compares the chronology ID. * Subclasses must compare any additional state that they store. * * @param other the other chronology to compare to, not null * @return the comparator value, negative if less, positive if greater */ @Override public int compareTo(Chronology other) { return getId().compareTo(other.getId()); } /** * Checks if this chronology is equal to another chronology. *

* The comparison is based on the entire state of the object. * * @implSpec * This implementation checks the type and calls * {@link #compareTo(java.time.chrono.Chronology)}. * * @param obj the object to check, null returns false * @return true if this is equal to the other chronology */ @Override public boolean equals(Object obj) { if (this == obj) { return true; } if (obj instanceof AbstractChronology) { return compareTo((AbstractChronology) obj) == 0; } return false; } /** * A hash code for this chronology. *

* The hash code should be based on the entire state of the object. * * @implSpec * This implementation is based on the chronology ID and class. * Subclasses should add any additional state that they store. * * @return a suitable hash code */ @Override public int hashCode() { return getClass().hashCode() ^ getId().hashCode(); } //----------------------------------------------------------------------- /** * Outputs this chronology as a {@code String}, using the chronology ID. * * @return a string representation of this chronology, not null */ @Override public String toString() { return getId(); } //----------------------------------------------------------------------- /** * Writes the Chronology using a * dedicated serialized form. *

     *  out.writeByte(1);  // identifies this as a Chronology
     *  out.writeUTF(getId());
     * 
* * @return the instance of {@code Ser}, not null */ @java.io.Serial Object writeReplace() { return new Ser(Ser.CHRONO_TYPE, this); } /** * Defend against malicious streams. * * @param s the stream to read * @throws java.io.InvalidObjectException always */ @java.io.Serial private void readObject(ObjectInputStream s) throws ObjectStreamException { throw new InvalidObjectException("Deserialization via serialization delegate"); } void writeExternal(DataOutput out) throws IOException { out.writeUTF(getId()); } static Chronology readExternal(DataInput in) throws IOException { String id = in.readUTF(); return Chronology.of(id); } }