1 /*
2 * Copyright (c) 2012, 2018, 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 * 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 */
57 package java.time;
58
59 import java.io.DataInput;
60 import java.io.DataOutput;
61 import java.io.IOException;
62 import java.io.InvalidObjectException;
63 import java.io.ObjectInputStream;
64 import java.io.Serializable;
65 import java.time.zone.ZoneRules;
66 import java.time.zone.ZoneRulesException;
67 import java.time.zone.ZoneRulesProvider;
68 import 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 */
90 final 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="{@docRoot}/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 }