1 /*

     2  * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

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    25 

    26 /*

    27  * This file is available under and governed by the GNU General Public

    28  * License version 2 only, as published by the Free Software Foundation.

    29  * However, the following notice accompanied the original version of this

    30  * file:

    31  *

    32  * Copyright (c) 2012, Stephen Colebourne & Michael Nascimento Santos

    33  *

    34  * All rights reserved.

    35  *

    36  * Redistribution and use in source and binary forms, with or without

    37  * modification, are permitted provided that the following conditions are met:

    38  *

    39  *  * Redistributions of source code must retain the above copyright notice,

    40  *    this list of conditions and the following disclaimer.

    41  *

    42  *  * Redistributions in binary form must reproduce the above copyright notice,

    43  *    this list of conditions and the following disclaimer in the documentation

    44  *    and/or other materials provided with the distribution.

    45  *

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

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

    48  *    without specific prior written permission.

    49  *

    50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

    51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

    52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

    53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR

    54  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

    55  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

    56  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

    57  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

    58  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

    59  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

    60  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    61  */

    62 

    63 /**

    64  * <p>

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

    66  * </p>

    67  * <p>

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

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

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

    71  * </p>

    72  * <p>

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

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

    75  * </p>

    76  * <p>

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

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

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

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

    81  * for a full discussion of the issues.

    82  * </p>

    83  * <p>

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

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

    86  * working with the "chrono" interfaces.

    87  * </p>

    88  * <p>

    89  * The supported calendar systems includes:

    90  * </p>

    91  * <ul>

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

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

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

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

    96  * </ul>

    97  *

    98  * <h3>Example</h3>

    99  * <p>

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

   101  * </p>

   102  * <pre>

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

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

   105  *       for (Chronology chrono : chronos) {

   106  *           ChronoLocalDate<?> date = chrono.dateNow();

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

   108  *       }

   109  * </pre>

   110  *

   111  * <p>

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

   113  * </p>

   114  * <pre>

   115  *   // Print the Thai Buddhist date

   116  *       ChronoLocalDate<?> now1 = Chronology.of("ThaiBuddhist").dateNow();

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

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

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

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

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

   122  *                 dow, day, month, year);

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

   124  *       ChronoLocalDate<?> first = now1

   125  *                 .with(ChronoField.DAY_OF_MONTH, 1)

   126  *                 .with(ChronoField.MONTH_OF_YEAR, 1);

   127  *       ChronoLocalDate<?> last = first

   128  *                 .plus(1, ChronoUnit.YEARS)

   129  *                 .minus(1, ChronoUnit.DAYS);

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

   131  *                 first, last);

   132  *  </pre>

   133  *

   134  * <p>

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

   136  * </p>

   137  * <pre>

   138  *   // Print the Thai Buddhist date

   139  *       ThaiBuddhistDate now1 = ThaiBuddhistDate.now();

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

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

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

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

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

   145  *                 dow, day, month, year);

   146  *

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

   148  *       ThaiBuddhistDate first = now1

   149  *                 .with(ChronoField.DAY_OF_MONTH, 1)

   150  *                 .with(ChronoField.MONTH_OF_YEAR, 1);

   151  *       ThaiBuddhistDate last = first

   152  *                 .plus(1, ChronoUnit.YEARS)

   153  *                 .minus(1, ChronoUnit.DAYS);

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

   155  *                 first, last);

   156  *  </pre>

   157  *

   158  * <h3>Package specification</h3>

   159  * <p>

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

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

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

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

   164  * </p>

   165  * <p>

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

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

   168  * </p>

   169  * @since JDK1.8

   170  */

   171 package java.time.chrono;