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.

    24  */

    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 package java.time.temporal;

    63 

    64 import static java.time.temporal.ChronoField.ERA;

    65 

    66 import java.time.DateTimeException;

    67 import java.time.format.DateTimeFormatterBuilder;

    68 import java.time.format.TextStyle;

    69 import java.util.Locale;

    70 

    71 /**

    72  * An era in the ISO calendar system.

    73  * <p>

    74  * The ISO-8601 standard does not define eras.

    75  * A definition has therefore been created with two eras - 'Current era' (CE) for

    76  * years from 0001-01-01 (ISO) and 'Before current era' (BCE) for years before that.

    77  * <p>

    78  * <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code ISOEra}.

    79  * Use {@code getValue()} instead.</b>

    80  *

    81  * <h3>Specification for implementors</h3>

    82  * This is an immutable and thread-safe enum.

    83  *

    84  * @since 1.8

    85  */

    86 enum ISOEra implements Era<ISOChrono> {

    87 

    88     /**

    89      * The singleton instance for the era BCE, 'Before Current Era'.

    90      * The 'ISO' part of the name emphasizes that this differs from the BCE

    91      * era in the Gregorian calendar system.

    92      * This has the numeric value of {@code 0}.

    93      */

    94     BCE,

    95     /**

    96      * The singleton instance for the era CE, 'Current Era'.

    97      * The 'ISO' part of the name emphasizes that this differs from the CE

    98      * era in the Gregorian calendar system.

    99      * This has the numeric value of {@code 1}.

   100      */

   101     CE;

   102 

   103     //-----------------------------------------------------------------------

   104     /**

   105      * Obtains an instance of {@code ISOEra} from an {@code int} value.

   106      * <p>

   107      * {@code ISOEra} is an enum representing the ISO eras of BCE/CE.

   108      * This factory allows the enum to be obtained from the {@code int} value.

   109      *

   110      * @param era  the BCE/CE value to represent, from 0 (BCE) to 1 (CE)

   111      * @return the era singleton, not null

   112      * @throws DateTimeException if the value is invalid

   113      */

   114     public static ISOEra of(int era) {

   115         switch (era) {

   116             case 0:

   117                 return BCE;

   118             case 1:

   119                 return CE;

   120             default:

   121                 throw new DateTimeException("Invalid era: " + era);

   122         }

   123     }

   124 

   125     //-----------------------------------------------------------------------

   126     /**

   127      * Gets the numeric era {@code int} value.

   128      * <p>

   129      * The era BCE has the value 0, while the era CE has the value 1.

   130      *

   131      * @return the era value, from 0 (BCE) to 1 (CE)

   132      */

   133     @Override

   134     public int getValue() {

   135         return ordinal();

   136     }

   137 

   138     @Override

   139     public ISOChrono getChrono() {

   140         return ISOChrono.INSTANCE;

   141     }

   142 

   143     // JDK8 default methods:

   144     //-----------------------------------------------------------------------

   145     @Override

   146     public ChronoLocalDate<ISOChrono> date(int year, int month, int day) {

   147         return getChrono().date(this, year, month, day);

   148     }

   149 

   150     @Override

   151     public ChronoLocalDate<ISOChrono> dateYearDay(int year, int dayOfYear) {

   152         return getChrono().dateYearDay(this, year, dayOfYear);

   153     }

   154 

   155     //-----------------------------------------------------------------------

   156     @Override

   157     public boolean isSupported(TemporalField field) {

   158         if (field instanceof ChronoField) {

   159             return field == ERA;

   160         }

   161         return field != null && field.doIsSupported(this);

   162     }

   163 

   164     @Override

   165     public ValueRange range(TemporalField field) {

   166         if (field == ERA) {

   167             return field.range();

   168         } else if (field instanceof ChronoField) {

   169             throw new DateTimeException("Unsupported field: " + field.getName());

   170         }

   171         return field.doRange(this);

   172     }

   173 

   174     @Override

   175     public int get(TemporalField field) {

   176         if (field == ERA) {

   177             return getValue();

   178         }

   179         return range(field).checkValidIntValue(getLong(field), field);

   180     }

   181 

   182     @Override

   183     public long getLong(TemporalField field) {

   184         if (field == ERA) {

   185             return getValue();

   186         } else if (field instanceof ChronoField) {

   187             throw new DateTimeException("Unsupported field: " + field.getName());

   188         }

   189         return field.doGet(this);

   190     }

   191 

   192     //-------------------------------------------------------------------------

   193     @Override

   194     public Temporal adjustInto(Temporal temporal) {

   195         return temporal.with(ERA, getValue());

   196     }

   197 

   198     //-----------------------------------------------------------------------

   199     @Override

   200     public String getText(TextStyle style, Locale locale) {

   201         return new DateTimeFormatterBuilder().appendText(ERA, style).toFormatter(locale).print(this);

   202     }

   203 

   204 }