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/*

 * 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,

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 *  * Neither the name of JSR-310 nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

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 */

/**

 * <p>

 * Generic API for calendar systems other than the default ISO.

 * </p>

 * <p>

 * The main API is based around the calendar system defined in ISO-8601.

 * However, there are other calendar systems, and this package provides basic support for them.

 * The alternate calendars are provided in the {@link java.time.chrono} package.

 * </p>

 * <p>

 * A calendar system is defined by the {@link java.time.chrono.Chronology} interface,

 * while a date in a calendar system is defined by the {@link java.time.chrono.ChronoLocalDate} interface.

 * </p>

 * <p>

 * It is intended that applications use the main API whenever possible, including code to read and write

 * from a persistent data store, such as a database, and to send dates and times across a network.

 * The "chrono" classes are then used at the user interface level to deal with localized input/output.

 * See {@link java.time.chrono.ChronoLocalDate ChronoLocalDate}

 * for a full discussion of the issues.

 * </p>

 * <p>

 * Using non-ISO calendar systems in an application introduces significant extra complexity.

 * Ensure that the warnings and recommendations in {@code ChronoLocalDate} have been read before

 * working with the "chrono" interfaces.

 * </p>

 * <p>

 * The supported calendar systems includes:

 * </p>

 * <ul>

 * <li>{@link java.time.chrono.HijrahChronology Hijrah calendar}</li>

 * <li>{@link java.time.chrono.JapaneseChronology Japanese calendar}</li>

 * <li>{@link java.time.chrono.MinguoChronology Minguo calendar}</li>

 * <li>{@link java.time.chrono.ThaiBuddhistChronology Thai Buddhist calendar}</li>

 * </ul>

 *

 * <h2>Example</h2>

 * <p>

 * This example lists todays date for all of the available calendars.

 * </p>

 * <pre>

 *   // Enumerate the list of available calendars and print todays date for each.

 *       Set<Chronology> chronos = Chronology.getAvailableChronologies();

 *       for (Chronology chrono : chronos) {

 *           ChronoLocalDate date = chrono.dateNow();

 *           System.out.printf("   %20s: %s%n", chrono.getId(), date.toString());

 *       }

 * </pre>

 *

 * <p>

 * This example creates and uses a date in a named non-ISO calendar system.

 * </p>

 * <pre>

 *   // Print the Thai Buddhist date

 *       ChronoLocalDate now1 = Chronology.of("ThaiBuddhist").dateNow();

 *       int day = now1.get(ChronoField.DAY_OF_MONTH);

 *       int dow = now1.get(ChronoField.DAY_OF_WEEK);

 *       int month = now1.get(ChronoField.MONTH_OF_YEAR);

 *       int year = now1.get(ChronoField.YEAR);

 *       System.out.printf("  Today is %s %s %d-%s-%d%n", now1.getChronology().getId(),

 *                 dow, day, month, year);

 *   // Print today's date and the last day of the year for the Thai Buddhist Calendar.

 *       ChronoLocalDate first = now1

 *                 .with(ChronoField.DAY_OF_MONTH, 1)

 *                 .with(ChronoField.MONTH_OF_YEAR, 1);

 *       ChronoLocalDate last = first

 *                 .plus(1, ChronoUnit.YEARS)

 *                 .minus(1, ChronoUnit.DAYS);

 *       System.out.printf("  %s: 1st of year: %s; end of year: %s%n", last.getChronology().getId(),

 *                 first, last);

 *  </pre>

 *

 * <p>

 * This example creates and uses a date in a specific ThaiBuddhist calendar system.

 * </p>

 * <pre>

 *   // Print the Thai Buddhist date

 *       ThaiBuddhistDate now1 = ThaiBuddhistDate.now();

 *       int day = now1.get(ChronoField.DAY_OF_MONTH);

 *       int dow = now1.get(ChronoField.DAY_OF_WEEK);

 *       int month = now1.get(ChronoField.MONTH_OF_YEAR);

 *       int year = now1.get(ChronoField.YEAR);

 *       System.out.printf("  Today is %s %s %d-%s-%d%n", now1.getChronology().getId(),

 *                 dow, day, month, year);

 *

 *   // Print today's date and the last day of the year for the Thai Buddhist Calendar.

 *       ThaiBuddhistDate first = now1

 *                 .with(ChronoField.DAY_OF_MONTH, 1)

 *                 .with(ChronoField.MONTH_OF_YEAR, 1);

 *       ThaiBuddhistDate last = first

 *                 .plus(1, ChronoUnit.YEARS)

 *                 .minus(1, ChronoUnit.DAYS);

 *       System.out.printf("  %s: 1st of year: %s; end of year: %s%n", last.getChronology().getId(),

 *                 first, last);

 *  </pre>

 *

 * <h2>Package specification</h2>

 * <p>

 * Unless otherwise noted, passing a null argument to a constructor or method in any class or interface

 * in this package will cause a {@link java.lang.NullPointerException NullPointerException} to be thrown.

 * The Javadoc "@param" definition is used to summarise the null-behavior.

 * The "@throws {@link java.lang.NullPointerException}" is not explicitly documented in each method.

 * </p>

 * <p>

 * All calculations should check for numeric overflow and throw either an {@link java.lang.ArithmeticException}

 * or a {@link java.time.DateTimeException}.

 * </p>

 * @since 1.8

 */

package java.time.chrono;