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
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24 */
25
26/*
27 * Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
28 *
29 * All rights reserved.
30 *
31 * Redistribution and use in source and binary forms, with or without
32 * modification, are permitted provided that the following conditions are met:
33 *
34 *  * Redistributions of source code must retain the above copyright notice,
35 *    this list of conditions and the following disclaimer.
36 *
37 *  * Redistributions in binary form must reproduce the above copyright notice,
38 *    this list of conditions and the following disclaimer in the documentation
39 *    and/or other materials provided with the distribution.
40 *
41 *  * Neither the name of JSR-310 nor the names of its contributors
42 *    may be used to endorse or promote products derived from this software
43 *    without specific prior written permission.
44 *
45 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
46 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
47 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
48 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
49 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
50 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
51 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
52 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
53 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
54 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
55 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56 */
57package java.time;
58
59import java.io.DataInput;
60import java.io.DataOutput;
61import java.io.IOException;
62import java.io.InvalidObjectException;
63import java.io.ObjectInputStream;
64import java.io.Serializable;
65import java.time.zone.ZoneRules;
66import java.time.zone.ZoneRulesException;
67import java.time.zone.ZoneRulesProvider;
68import java.util.Objects;
69
70/**
71 * A geographical region where the same time-zone rules apply.
72 * <p>
73 * Time-zone information is categorized as a set of rules defining when and
74 * how the offset from UTC/Greenwich changes. These rules are accessed using
75 * identifiers based on geographical regions, such as countries or states.
76 * The most common region classification is the Time Zone Database (TZDB),
77 * which defines regions such as 'Europe/Paris' and 'Asia/Tokyo'.
78 * <p>
79 * The region identifier, modeled by this class, is distinct from the
80 * underlying rules, modeled by {@link ZoneRules}.
81 * The rules are defined by governments and change frequently.
82 * By contrast, the region identifier is well-defined and long-lived.
83 * This separation also allows rules to be shared between regions if appropriate.
84 *
85 * @implSpec
86 * This class is immutable and thread-safe.
87 *
88 * @since 1.8
89 */
90final class ZoneRegion extends ZoneId implements Serializable {
91
92    /**
93     * Serialization version.
94     */
95    private static final long serialVersionUID = 8386373296231747096L;
96    /**
97     * The time-zone ID, not null.
98     */
99    private final String id;
100    /**
101     * The time-zone rules, null if zone ID was loaded leniently.
102     */
103    private final transient ZoneRules rules;
104
105    /**
106     * Obtains an instance of {@code ZoneId} from an identifier.
107     *
108     * @param zoneId  the time-zone ID, not null
109     * @param checkAvailable  whether to check if the zone ID is available
110     * @return the zone ID, not null
111     * @throws DateTimeException if the ID format is invalid
112     * @throws ZoneRulesException if checking availability and the ID cannot be found
113     */
114    static ZoneRegion ofId(String zoneId, boolean checkAvailable) {
115        Objects.requireNonNull(zoneId, "zoneId");
116        checkName(zoneId);
117        ZoneRules rules = null;
118        try {
119            // always attempt load for better behavior after deserialization
120            rules = ZoneRulesProvider.getRules(zoneId, true);
121        } catch (ZoneRulesException ex) {
122            if (checkAvailable) {
123                throw ex;
124            }
125        }
126        return new ZoneRegion(zoneId, rules);
127    }
128
129    /**
130     * Checks that the given string is a legal ZondId name.
131     *
132     * @param zoneId  the time-zone ID, not null
133     * @throws DateTimeException if the ID format is invalid
134     */
135    private static void checkName(String zoneId) {
136        int n = zoneId.length();
137        if (n < 2) {
138           throw new DateTimeException("Invalid ID for region-based ZoneId, invalid format: " + zoneId);
139        }
140        for (int i = 0; i < n; i++) {
141            char c = zoneId.charAt(i);
142            if (c >= 'a' && c <= 'z') continue;
143            if (c >= 'A' && c <= 'Z') continue;
144            if (c == '/' && i != 0) continue;
145            if (c >= '0' && c <= '9' && i != 0) continue;
146            if (c == '~' && i != 0) continue;
147            if (c == '.' && i != 0) continue;
148            if (c == '_' && i != 0) continue;
149            if (c == '+' && i != 0) continue;
150            if (c == '-' && i != 0) continue;
151            throw new DateTimeException("Invalid ID for region-based ZoneId, invalid format: " + zoneId);
152        }
153    }
154
155    //-------------------------------------------------------------------------
156    /**
157     * Constructor.
158     *
159     * @param id  the time-zone ID, not null
160     * @param rules  the rules, null for lazy lookup
161     */
162    ZoneRegion(String id, ZoneRules rules) {
163        this.id = id;
164        this.rules = rules;
165    }
166
167    //-----------------------------------------------------------------------
168    @Override
169    public String getId() {
170        return id;
171    }
172
173    @Override
174    public ZoneRules getRules() {
175        // additional query for group provider when null allows for possibility
176        // that the provider was updated after the ZoneId was created
177        return (rules != null ? rules : ZoneRulesProvider.getRules(id, false));
178    }
179
180    //-----------------------------------------------------------------------
181    /**
182     * Writes the object using a
183     * <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
184     * @serialData
185     * <pre>
186     *  out.writeByte(7);  // identifies a ZoneId (not ZoneOffset)
187     *  out.writeUTF(zoneId);
188     * </pre>
189     *
190     * @return the instance of {@code Ser}, not null
191     */
192    private Object writeReplace() {
193        return new Ser(Ser.ZONE_REGION_TYPE, this);
194    }
195
196    /**
197     * Defend against malicious streams.
198     *
199     * @param s the stream to read
200     * @throws InvalidObjectException always
201     */
202    private void readObject(ObjectInputStream s) throws InvalidObjectException {
203        throw new InvalidObjectException("Deserialization via serialization delegate");
204    }
205
206    @Override
207    void write(DataOutput out) throws IOException {
208        out.writeByte(Ser.ZONE_REGION_TYPE);
209        writeExternal(out);
210    }
211
212    void writeExternal(DataOutput out) throws IOException {
213        out.writeUTF(id);
214    }
215
216    static ZoneId readExternal(DataInput in) throws IOException {
217        String id = in.readUTF();
218        return ZoneId.of(id, false);
219    }
220
221}
222