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 * 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) 2011-2012, 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.DataInput;
65import java.io.DataOutput;
66import java.io.Externalizable;
67import java.io.IOException;
68import java.io.InvalidClassException;
69import java.io.ObjectInput;
70import java.io.ObjectOutput;
71import java.io.StreamCorruptedException;
72import java.time.ZoneOffset;
73
74/**
75 * The shared serialization delegate for this package.
76 *
77 * @implNote
78 * This class is mutable and should be created once per serialization.
79 *
80 * @serial include
81 * @since 1.8
82 */
83final class Ser implements Externalizable {
84
85    /**
86     * Serialization version.
87     */
88    private static final long serialVersionUID = -8885321777449118786L;
89
90    /** Type for ZoneRules. */
91    static final byte ZRULES = 1;
92    /** Type for ZoneOffsetTransition. */
93    static final byte ZOT = 2;
94    /** Type for ZoneOffsetTransition. */
95    static final byte ZOTRULE = 3;
96
97    /** The type being serialized. */
98    private byte type;
99    /** The object being serialized. */
100    private Object object;
101
102    /**
103     * Constructor for deserialization.
104     */
105    public Ser() {
106    }
107
108    /**
109     * Creates an instance for serialization.
110     *
111     * @param type  the type
112     * @param object  the object
113     */
114    Ser(byte type, Object object) {
115        this.type = type;
116        this.object = object;
117    }
118
119    //-----------------------------------------------------------------------
120    /**
121     * Implements the {@code Externalizable} interface to write the object.
122     * @serialData
123     * Each serializable class is mapped to a type that is the first byte
124     * in the stream.  Refer to each class {@code writeReplace}
125     * serialized form for the value of the type and sequence of values for the type.
126     *
127     * <ul>
128     * <li><a href="../../../serialized-form.html#java.time.zone.ZoneRules">ZoneRules.writeReplace</a>
129     * <li><a href="../../../serialized-form.html#java.time.zone.ZoneOffsetTransition">ZoneOffsetTransition.writeReplace</a>
130     * <li><a href="../../../serialized-form.html#java.time.zone.ZoneOffsetTransitionRule">ZoneOffsetTransitionRule.writeReplace</a>
131     * </ul>
132     *
133     * @param out  the data stream to write to, not null
134     */
135    @Override
136    public void writeExternal(ObjectOutput out) throws IOException {
137        writeInternal(type, object, out);
138    }
139
140    static void write(Object object, DataOutput out) throws IOException {
141        writeInternal(ZRULES, object, out);
142    }
143
144    private static void writeInternal(byte type, Object object, DataOutput out) throws IOException {
145        out.writeByte(type);
146        switch (type) {
147            case ZRULES:
148                ((ZoneRules) object).writeExternal(out);
149                break;
150            case ZOT:
151                ((ZoneOffsetTransition) object).writeExternal(out);
152                break;
153            case ZOTRULE:
154                ((ZoneOffsetTransitionRule) object).writeExternal(out);
155                break;
156            default:
157                throw new InvalidClassException("Unknown serialized type");
158        }
159    }
160
161    //-----------------------------------------------------------------------
162    /**
163     * Implements the {@code Externalizable} interface to read the object.
164     * @serialData
165     * The streamed type and parameters defined by the type's {@code writeReplace}
166     * method are read and passed to the corresponding static factory for the type
167     * to create a new instance.  That instance is returned as the de-serialized
168     * {@code Ser} object.
169     *
170     * <ul>
171     * <li><a href="../../../serialized-form.html#java.time.zone.ZoneRules">ZoneRules</a>
172     * - {@code ZoneRules.of(standardTransitions, standardOffsets, savingsInstantTransitions, wallOffsets, lastRules);}
173     * <li><a href="../../../serialized-form.html#java.time.zone.ZoneOffsetTransition">ZoneOffsetTransition</a>
174     * - {@code ZoneOffsetTransition of(LocalDateTime.ofEpochSecond(epochSecond), offsetBefore, offsetAfter);}
175     * <li><a href="../../../serialized-form.html#java.time.zone.ZoneOffsetTransitionRule">ZoneOffsetTransitionRule</a>
176     * - {@code ZoneOffsetTransitionRule.of(month, dom, dow, time, timeEndOfDay, timeDefinition, standardOffset, offsetBefore, offsetAfter);}
177     * </ul>
178     * @param in  the data to read, not null
179     */
180    @Override
181    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
182        type = in.readByte();
183        object = readInternal(type, in);
184    }
185
186    static Object read(DataInput in) throws IOException, ClassNotFoundException {
187        byte type = in.readByte();
188        return readInternal(type, in);
189    }
190
191    private static Object readInternal(byte type, DataInput in) throws IOException, ClassNotFoundException {
192        switch (type) {
193            case ZRULES:
194                return ZoneRules.readExternal(in);
195            case ZOT:
196                return ZoneOffsetTransition.readExternal(in);
197            case ZOTRULE:
198                return ZoneOffsetTransitionRule.readExternal(in);
199            default:
200                throw new StreamCorruptedException("Unknown serialized type");
201        }
202    }
203
204    /**
205     * Returns the object that will replace this one.
206     *
207     * @return the read object, should never be null
208     */
209    private Object readResolve() {
210         return object;
211    }
212
213    //-----------------------------------------------------------------------
214    /**
215     * Writes the state to the stream.
216     *
217     * @param offset  the offset, not null
218     * @param out  the output stream, not null
219     * @throws IOException if an error occurs
220     */
221    static void writeOffset(ZoneOffset offset, DataOutput out) throws IOException {
222        final int offsetSecs = offset.getTotalSeconds();
223        int offsetByte = offsetSecs % 900 == 0 ? offsetSecs / 900 : 127;  // compress to -72 to +72
224        out.writeByte(offsetByte);
225        if (offsetByte == 127) {
226            out.writeInt(offsetSecs);
227        }
228    }
229
230    /**
231     * Reads the state from the stream.
232     *
233     * @param in  the input stream, not null
234     * @return the created object, not null
235     * @throws IOException if an error occurs
236     */
237    static ZoneOffset readOffset(DataInput in) throws IOException {
238        int offsetByte = in.readByte();
239        return (offsetByte == 127 ? ZoneOffset.ofTotalSeconds(in.readInt()) : ZoneOffset.ofTotalSeconds(offsetByte * 900));
240    }
241
242    //-----------------------------------------------------------------------
243    /**
244     * Writes the state to the stream.
245     *
246     * @param epochSec  the epoch seconds, not null
247     * @param out  the output stream, not null
248     * @throws IOException if an error occurs
249     */
250    static void writeEpochSec(long epochSec, DataOutput out) throws IOException {
251        if (epochSec >= -4575744000L && epochSec < 10413792000L && epochSec % 900 == 0) {  // quarter hours between 1825 and 2300
252            int store = (int) ((epochSec + 4575744000L) / 900);
253            out.writeByte((store >>> 16) & 255);
254            out.writeByte((store >>> 8) & 255);
255            out.writeByte(store & 255);
256        } else {
257            out.writeByte(255);
258            out.writeLong(epochSec);
259        }
260    }
261
262    /**
263     * Reads the state from the stream.
264     *
265     * @param in  the input stream, not null
266     * @return the epoch seconds, not null
267     * @throws IOException if an error occurs
268     */
269    static long readEpochSec(DataInput in) throws IOException {
270        int hiByte = in.readByte() & 255;
271        if (hiByte == 255) {
272            return in.readLong();
273        } else {
274            int midByte = in.readByte() & 255;
275            int loByte = in.readByte() & 255;
276            long tot = ((hiByte << 16) + (midByte << 8) + loByte);
277            return (tot * 900) - 4575744000L;
278        }
279    }
280
281}
282