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
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   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.
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  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
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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
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  60  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  61  */
  62 package java.time.chrono;
  63 
  64 import static java.time.temporal.ChronoField.ERA;
  65 
  66 import java.time.DateTimeException;
  67 import java.time.temporal.ChronoField;
  68 import java.time.temporal.TemporalField;
  69 import java.time.temporal.UnsupportedTemporalTypeException;
  70 import java.time.temporal.ValueRange;
  71 
  72 /**
  73  * An era in the Hijrah calendar system.
  74  * <p>
  75  * The Hijrah calendar system has only one era covering the
  76  * proleptic years greater than zero.
  77  * <p>
  78  * <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code HijrahEra}.
  79  * Use {@code getValue()} instead.</b>
  80  *
  81  * @implSpec
  82  * This is an immutable and thread-safe enum.
  83  *
  84  * @since 1.8
  85  */
  86 public enum HijrahEra implements Era {
  87 
  88     /**
  89      * The singleton instance for the current era, 'Anno Hegirae',
  90      * which has the numeric value 1.
  91      */
  92     AH;
  93 
  94     //-----------------------------------------------------------------------
  95     /**
  96      * Obtains an instance of {@code HijrahEra} from an {@code int} value.
  97      * <p>
  98      * The current era, which is the only accepted value, has the value 1
  99      *
 100      * @param hijrahEra  the era to represent, only 1 supported
 101      * @return the HijrahEra.AH singleton, not null
 102      * @throws DateTimeException if the value is invalid
 103      */
 104     public static HijrahEra of(int hijrahEra) {
 105         if (hijrahEra == 1 ) {
 106             return AH;
 107         } else {
 108             throw new DateTimeException("Invalid era: " + hijrahEra);
 109         }
 110     }
 111 
 112     //-----------------------------------------------------------------------
 113     /**
 114      * Gets the numeric era {@code int} value.
 115      * <p>
 116      * The era AH has the value 1.
 117      *
 118      * @return the era value, 1 (AH)
 119      */
 120     @Override
 121     public int getValue() {
 122         return 1;
 123     }
 124 
 125     //-----------------------------------------------------------------------
 126     /**
 127      * Gets the range of valid values for the specified field.
 128      * <p>
 129      * The range object expresses the minimum and maximum valid values for a field.
 130      * This era is used to enhance the accuracy of the returned range.
 131      * If it is not possible to return the range, because the field is not supported
 132      * or for some other reason, an exception is thrown.
 133      * <p>
 134      * If the field is a {@link ChronoField} then the query is implemented here.
 135      * The {@code ERA} field returns the range.
 136      * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
 137      * <p>
 138      * If the field is not a {@code ChronoField}, then the result of this method
 139      * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
 140      * passing {@code this} as the argument.
 141      * Whether the range can be obtained is determined by the field.
 142      * <p>
 143      * The {@code ERA} field returns a range for the one valid Hijrah era.
 144      *
 145      * @param field  the field to query the range for, not null
 146      * @return the range of valid values for the field, not null
 147      * @throws DateTimeException if the range for the field cannot be obtained
 148      * @throws UnsupportedTemporalTypeException if the unit is not supported
 149      */
 150     @Override  // override as super would return range from 0 to 1
 151     public ValueRange range(TemporalField field) {
 152         if (field == ERA) {
 153             return ValueRange.of(1, 1);
 154         }
 155         return Era.super.range(field);
 156     }
 157 
 158 }