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 * 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.ObjectStreamException;
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 import java.util.regex.Pattern;
70
71 /**
72 * A geographical region where the same time-zone rules apply.
73 * <p>
74 * Time-zone information is categorized as a set of rules defining when and
75 * how the offset from UTC/Greenwich changes. These rules are accessed using
76 * identifiers based on geographical regions, such as countries or states.
77 * The most common region classification is the Time Zone Database (TZDB),
78 * which defines regions such as 'Europe/Paris' and 'Asia/Tokyo'.
79 * <p>
80 * The region identifier, modeled by this class, is distinct from the
81 * underlying rules, modeled by {@link ZoneRules}.
82 * The rules are defined by governments and change frequently.
83 * By contrast, the region identifier is well-defined and long-lived.
84 * This separation also allows rules to be shared between regions if appropriate.
85 *
86 * <h3>Specification for implementors</h3>
87 * This class is immutable and thread-safe.
88 *
89 * @since 1.8
90 */
91 final class ZoneRegion extends ZoneId implements Serializable {
92
93 /**
94 * Serialization version.
95 */
96 private static final long serialVersionUID = 8386373296231747096L;
97 /**
98 * The time-zone ID, not null.
99 */
100 private final String id;
101 /**
102 * The time-zone rules, null if zone ID was loaded leniently.
103 */
104 private final transient ZoneRules rules;
105
106 /**
107 * Obtains an instance of {@code ZoneId} from an identifier.
108 *
109 * @param zoneId the time-zone ID, not null
110 * @param checkAvailable whether to check if the zone ID is available
111 * @return the zone ID, not null
112 * @throws DateTimeException if the ID format is invalid
113 * @throws ZoneRulesException if checking availability and the ID cannot be found
114 */
115 static ZoneRegion ofId(String zoneId, boolean checkAvailable) {
116 Objects.requireNonNull(zoneId, "zoneId");
117 checkName(zoneId);
118 ZoneRules rules = null;
119 try {
120 // always attempt load for better behavior after deserialization
121 rules = ZoneRulesProvider.getRules(zoneId, true);
122 } catch (ZoneRulesException ex) {
123 if (checkAvailable) {
124 throw ex;
125 }
126 }
127 return new ZoneRegion(zoneId, rules);
128 }
129
130 /**
131 * Checks that the given string is a legal ZondId name.
132 *
133 * @param zoneId the time-zone ID, not null
134 * @throws DateTimeException if the ID format is invalid
135 */
136 private static void checkName(String zoneId) {
137 int n = zoneId.length();
138 if (n < 2) {
139 throw new DateTimeException("Invalid ID for region-based ZoneId, invalid format: " + zoneId);
140 }
141 for (int i = 0; i < n; i++) {
142 char c = zoneId.charAt(i);
143 if (c >= 'a' && c <= 'z') continue;
144 if (c >= 'A' && c <= 'Z') continue;
145 if (c == '/' && i != 0) continue;
146 if (c >= '0' && c <= '9' && 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 if (c == '-' && i != 0) continue;
152 throw new DateTimeException("Invalid ID for region-based ZoneId, invalid format: " + zoneId);
153 }
154 }
155
156 /**
157 * Obtains an instance of {@code ZoneId} wrapping an offset.
158 * <p>
159 * For example, zone IDs like 'UTC', 'GMT', 'UT' and 'UTC+01:30' will be setup here.
160 *
161 * @param zoneId the time-zone ID, not null
162 * @param offset the offset, not null
163 * @return the zone ID, not null
164 */
165 static ZoneRegion ofPrefixedOffset(String zoneId, ZoneOffset offset) {
166 return new ZoneRegion(zoneId, offset.getRules());
167 }
168
169 //-------------------------------------------------------------------------
170 /**
171 * Constructor.
172 *
173 * @param id the time-zone ID, not null
174 * @param rules the rules, null for lazy lookup
175 */
176 ZoneRegion(String id, ZoneRules rules) {
177 this.id = id;
178 this.rules = rules;
179 }
180
181 //-----------------------------------------------------------------------
182 @Override
183 public String getId() {
184 return id;
185 }
186
187 @Override
188 public ZoneRules getRules() {
189 // additional query for group provider when null allows for possibility
190 // that the provider was updated after the ZoneId was created
191 return (rules != null ? rules : ZoneRulesProvider.getRules(id, false));
192 }
193
194 //-----------------------------------------------------------------------
195 /**
196 * Writes the object using a
197 * <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
198 * <pre>
199 * out.writeByte(7); // identifies this as a ZoneId (not ZoneOffset)
200 * out.writeUTF(zoneId);
201 * </pre>
202 *
203 * @return the instance of {@code Ser}, not null
204 */
205 private Object writeReplace() {
206 return new Ser(Ser.ZONE_REGION_TYPE, this);
207 }
208
209 /**
210 * Defend against malicious streams.
211 * @return never
212 * @throws InvalidObjectException always
213 */
214 private Object readResolve() throws ObjectStreamException {
215 throw new InvalidObjectException("Deserialization via serialization delegate");
216 }
217
218 @Override
219 void write(DataOutput out) throws IOException {
220 out.writeByte(Ser.ZONE_REGION_TYPE);
221 writeExternal(out);
222 }
223
224 void writeExternal(DataOutput out) throws IOException {
225 out.writeUTF(id);
226 }
227
228 static ZoneId readExternal(DataInput in) throws IOException {
229 String id = in.readUTF();
230 return ZoneId.of(id, false);
231 }
232
233 }