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 * 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) 2009-2012, 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
58 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
59 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
60 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61 */
62package java.time.zone;
63
64import java.io.ByteArrayInputStream;
65import java.io.BufferedInputStream;
66import java.io.DataInputStream;
67import java.io.File;
68import java.io.FileInputStream;
69import java.io.IOException;
70import java.io.StreamCorruptedException;
71import java.util.Arrays;
72import java.util.HashSet;
73import java.util.List;
74import java.util.Map;
75import java.util.NavigableMap;
76import java.util.Objects;
77import java.util.Set;
78import java.util.TreeMap;
79import java.util.concurrent.ConcurrentHashMap;
80
81/**
82 * Loads time-zone rules for 'TZDB'.
83 *
84 * @since 1.8
85 */
86final class TzdbZoneRulesProvider extends ZoneRulesProvider {
87
88    /**
89     * All the regions that are available.
90     */
91    private List<String> regionIds;
92    /**
93     * Version Id of this tzdb rules
94     */
95    private String versionId;
96    /**
97     * Region to rules mapping
98     */
99    private final Map<String, Object> regionToRules = new ConcurrentHashMap<>();
100
101    /**
102     * Creates an instance.
103     * Created by the {@code ServiceLoader}.
104     *
105     * @throws ZoneRulesException if unable to load
106     */
107    public TzdbZoneRulesProvider() {
108        try {
109            String libDir = System.getProperty("java.home") + File.separator + "lib";
110            try (DataInputStream dis = new DataInputStream(
111                     new BufferedInputStream(new FileInputStream(
112                         new File(libDir, "tzdb.dat"))))) {
113                load(dis);
114            }
115        } catch (Exception ex) {
116            throw new ZoneRulesException("Unable to load TZDB time-zone rules", ex);
117        }
118    }
119
120    @Override
121    protected Set<String> provideZoneIds() {
122        return new HashSet<>(regionIds);
123    }
124
125    @Override
126    protected ZoneRules provideRules(String zoneId, boolean forCaching) {
127        // forCaching flag is ignored because this is not a dynamic provider
128        Object obj = regionToRules.get(zoneId);
129        if (obj == null) {
130            throw new ZoneRulesException("Unknown time-zone ID: " + zoneId);
131        }
132        try {
133            if (obj instanceof byte[]) {
134                byte[] bytes = (byte[]) obj;
135                DataInputStream dis = new DataInputStream(new ByteArrayInputStream(bytes));
136                obj = Ser.read(dis);
137                regionToRules.put(zoneId, obj);
138            }
139            return (ZoneRules) obj;
140        } catch (Exception ex) {
141            throw new ZoneRulesException("Invalid binary time-zone data: TZDB:" + zoneId + ", version: " + versionId, ex);
142        }
143    }
144
145    @Override
146    protected NavigableMap<String, ZoneRules> provideVersions(String zoneId) {
147        TreeMap<String, ZoneRules> map = new TreeMap<>();
148        ZoneRules rules = getRules(zoneId, false);
149        if (rules != null) {
150            map.put(versionId, rules);
151        }
152        return map;
153    }
154
155    /**
156     * Loads the rules from a DateInputStream, often in a jar file.
157     *
158     * @param dis  the DateInputStream to load, not null
159     * @throws Exception if an error occurs
160     */
161    private void load(DataInputStream dis) throws Exception {
162        if (dis.readByte() != 1) {
163            throw new StreamCorruptedException("File format not recognised");
164        }
165        // group
166        String groupId = dis.readUTF();
167        if ("TZDB".equals(groupId) == false) {
168            throw new StreamCorruptedException("File format not recognised");
169        }
170        // versions
171        int versionCount = dis.readShort();
172        for (int i = 0; i < versionCount; i++) {
173            versionId = dis.readUTF();
174        }
175        // regions
176        int regionCount = dis.readShort();
177        String[] regionArray = new String[regionCount];
178        for (int i = 0; i < regionCount; i++) {
179            regionArray[i] = dis.readUTF();
180        }
181        regionIds = Arrays.asList(regionArray);
182        // rules
183        int ruleCount = dis.readShort();
184        Object[] ruleArray = new Object[ruleCount];
185        for (int i = 0; i < ruleCount; i++) {
186            byte[] bytes = new byte[dis.readShort()];
187            dis.readFully(bytes);
188            ruleArray[i] = bytes;
189        }
190        // link version-region-rules
191        for (int i = 0; i < versionCount; i++) {
192            int versionRegionCount = dis.readShort();
193            regionToRules.clear();
194            for (int j = 0; j < versionRegionCount; j++) {
195                String region = regionArray[dis.readShort()];
196                Object rule = ruleArray[dis.readShort() & 0xffff];
197                regionToRules.put(region, rule);
198            }
199        }
200    }
201
202    @Override
203    public String toString() {
204        return "TZDB[" + versionId + "]";
205    }
206}
207