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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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).
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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
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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 */
62package java.time.chrono;
63
64import static java.time.temporal.ChronoField.ERA;
65
66import java.time.DateTimeException;
67import java.time.temporal.ChronoField;
68import java.time.temporal.TemporalField;
69import java.time.temporal.UnsupportedTemporalTypeException;
70import 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 */
86public 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}
159