1 /*
   2  * Copyright (c) 2012, 2016, 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.
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  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  */
  62 package build.tools.tzdb;
  63 
  64 import java.io.DataOutput;
  65 import java.io.IOException;
  66 import java.io.ObjectOutput;
  67 import java.time.LocalDateTime;
  68 import java.time.LocalTime;
  69 import java.time.ZoneOffset;
  70 import java.time.zone.ZoneOffsetTransition;
  71 import java.time.zone.ZoneOffsetTransitionRule;
  72 import java.time.zone.ZoneOffsetTransitionRule.TimeDefinition;
  73 import java.util.Arrays;
  74 import java.util.ArrayList;
  75 import java.util.List;
  76 
  77 /**
  78  * Duplicated code of javax.time.zone.ZoneRules, ZoneOffsetTransitionRule
  79  * and Ser to generate the serialization form output of ZoneRules for
  80  * tzdb.jar.
  81  *
  82  * Implementation here is the copy/paste of ZoneRules, ZoneOffsetTransitionRule
  83  * and Ser in javax.time.zone package. Make sure the code here is synchrionozed
  84  * with the serialization implementation there.
  85  *
  86  * @since 1.8
  87  */
  88 
  89 final class ZoneRules {
  90 
  91     /**
  92      * The transitions between standard offsets (epoch seconds), sorted.
  93      */
  94     private final long[] standardTransitions;
  95     /**
  96      * The standard offsets.
  97      */
  98     private final ZoneOffset[] standardOffsets;
  99     /**
 100      * The transitions between instants (epoch seconds), sorted.
 101      */
 102     private final long[] savingsInstantTransitions;
 103 
 104     /**
 105      * The wall offsets.
 106      */
 107     private final ZoneOffset[] wallOffsets;
 108     /**
 109      * The last rule.
 110      */
 111     private final ZoneOffsetTransitionRule[] lastRules;
 112 
 113     /**
 114      * Creates an instance.
 115      *
 116      * @param baseStandardOffset  the standard offset to use before legal rules were set, not null
 117      * @param baseWallOffset  the wall offset to use before legal rules were set, not null
 118      * @param standardOffsetTransitionList  the list of changes to the standard offset, not null
 119      * @param transitionList  the list of transitions, not null
 120      * @param lastRules  the recurring last rules, size 16 or less, not null
 121      */
 122     ZoneRules(ZoneOffset baseStandardOffset,
 123               ZoneOffset baseWallOffset,
 124               List<ZoneOffsetTransition> standardOffsetTransitionList,
 125               List<ZoneOffsetTransition> transitionList,
 126               List<ZoneOffsetTransitionRule> lastRules) {
 127 
 128         this.standardTransitions = new long[standardOffsetTransitionList.size()];
 129 
 130         this.standardOffsets = new ZoneOffset[standardOffsetTransitionList.size() + 1];
 131         this.standardOffsets[0] = baseStandardOffset;
 132         for (int i = 0; i < standardOffsetTransitionList.size(); i++) {
 133             this.standardTransitions[i] = standardOffsetTransitionList.get(i).toEpochSecond();
 134             this.standardOffsets[i + 1] = standardOffsetTransitionList.get(i).getOffsetAfter();
 135         }
 136 
 137         // convert savings transitions to locals
 138         List<ZoneOffset> localTransitionOffsetList = new ArrayList<>();
 139         localTransitionOffsetList.add(baseWallOffset);
 140         for (ZoneOffsetTransition trans : transitionList) {
 141             localTransitionOffsetList.add(trans.getOffsetAfter());
 142         }
 143 
 144         this.wallOffsets = localTransitionOffsetList.toArray(new ZoneOffset[localTransitionOffsetList.size()]);
 145 
 146         // convert savings transitions to instants
 147         this.savingsInstantTransitions = new long[transitionList.size()];
 148         for (int i = 0; i < transitionList.size(); i++) {
 149             this.savingsInstantTransitions[i] = transitionList.get(i).toEpochSecond();
 150         }
 151 
 152         // last rules
 153         if (lastRules.size() > 16) {
 154             throw new IllegalArgumentException("Too many transition rules");
 155         }
 156         this.lastRules = lastRules.toArray(new ZoneOffsetTransitionRule[lastRules.size()]);
 157     }
 158 
 159     /** Type for ZoneRules. */
 160     static final byte ZRULES = 1;
 161 
 162     /**
 163      * Writes the state to the stream.
 164      *
 165      * @param out  the output stream, not null
 166      * @throws IOException if an error occurs
 167      */
 168     void writeExternal(DataOutput out) throws IOException {
 169         out.writeByte(ZRULES);
 170         out.writeInt(standardTransitions.length);
 171         for (long trans : standardTransitions) {
 172             writeEpochSec(trans, out);
 173         }
 174         for (ZoneOffset offset : standardOffsets) {
 175             writeOffset(offset, out);
 176         }
 177         out.writeInt(savingsInstantTransitions.length);
 178         for (long trans : savingsInstantTransitions) {
 179             writeEpochSec(trans, out);
 180         }
 181         for (ZoneOffset offset : wallOffsets) {
 182             writeOffset(offset, out);
 183         }
 184         out.writeByte(lastRules.length);
 185         for (ZoneOffsetTransitionRule rule : lastRules) {
 186             writeRule(rule, out);
 187         }
 188     }
 189 
 190     /**
 191      * Writes the state the ZoneOffset to the stream.
 192      *
 193      * @param offset  the offset, not null
 194      * @param out  the output stream, not null
 195      * @throws IOException if an error occurs
 196      */
 197     static void writeOffset(ZoneOffset offset, DataOutput out) throws IOException {
 198         final int offsetSecs = offset.getTotalSeconds();
 199         int offsetByte = offsetSecs % 900 == 0 ? offsetSecs / 900 : 127;  // compress to -72 to +72
 200         out.writeByte(offsetByte);
 201         if (offsetByte == 127) {
 202             out.writeInt(offsetSecs);
 203         }
 204     }
 205 
 206     /**
 207      * Writes the epoch seconds to the stream.
 208      *
 209      * @param epochSec  the epoch seconds, not null
 210      * @param out  the output stream, not null
 211      * @throws IOException if an error occurs
 212      */
 213     static void writeEpochSec(long epochSec, DataOutput out) throws IOException {
 214         if (epochSec >= -4575744000L && epochSec < 10413792000L && epochSec % 900 == 0) {  // quarter hours between 1825 and 2300
 215             int store = (int) ((epochSec + 4575744000L) / 900);
 216             out.writeByte((store >>> 16) & 255);
 217             out.writeByte((store >>> 8) & 255);
 218             out.writeByte(store & 255);
 219         } else {
 220             out.writeByte(255);
 221             out.writeLong(epochSec);
 222         }
 223     }
 224 
 225     /**
 226      * Writes the state of the transition rule to the stream.
 227      *
 228      * @param rule  the transition rule, not null
 229      * @param out  the output stream, not null
 230      * @throws IOException if an error occurs
 231      */
 232     static void writeRule(ZoneOffsetTransitionRule rule, DataOutput out) throws IOException {
 233         int month = rule.getMonth().getValue();
 234         byte dom = (byte)rule.getDayOfMonthIndicator();
 235         int dow = (rule.getDayOfWeek() == null ? -1 : rule.getDayOfWeek().getValue());
 236         LocalTime time = rule.getLocalTime();
 237         boolean timeEndOfDay = rule.isMidnightEndOfDay();
 238         TimeDefinition timeDefinition = rule.getTimeDefinition();
 239         ZoneOffset standardOffset = rule.getStandardOffset();
 240         ZoneOffset offsetBefore = rule.getOffsetBefore();
 241         ZoneOffset offsetAfter = rule.getOffsetAfter();
 242 
 243         int timeSecs = (timeEndOfDay ? 86400 : time.toSecondOfDay());
 244         int stdOffset = standardOffset.getTotalSeconds();
 245         int beforeDiff = offsetBefore.getTotalSeconds() - stdOffset;
 246         int afterDiff = offsetAfter.getTotalSeconds() - stdOffset;
 247         int timeByte = (timeSecs % 3600 == 0 ? (timeEndOfDay ? 24 : time.getHour()) : 31);
 248         int stdOffsetByte = (stdOffset % 900 == 0 ? stdOffset / 900 + 128 : 255);
 249         int beforeByte = (beforeDiff == 0 || beforeDiff == 1800 || beforeDiff == 3600 ? beforeDiff / 1800 : 3);
 250         int afterByte = (afterDiff == 0 || afterDiff == 1800 || afterDiff == 3600 ? afterDiff / 1800 : 3);
 251         int dowByte = (dow == -1 ? 0 : dow);
 252         int b = (month << 28) +                     // 4 bytes
 253                 ((dom + 32) << 22) +                // 6 bytes
 254                 (dowByte << 19) +                   // 3 bytes
 255                 (timeByte << 14) +                  // 5 bytes
 256                 (timeDefinition.ordinal() << 12) +  // 2 bytes
 257                 (stdOffsetByte << 4) +              // 8 bytes
 258                 (beforeByte << 2) +                 // 2 bytes
 259                 afterByte;                          // 2 bytes
 260         out.writeInt(b);
 261         if (timeByte == 31) {
 262             out.writeInt(timeSecs);
 263         }
 264         if (stdOffsetByte == 255) {
 265             out.writeInt(stdOffset);
 266         }
 267         if (beforeByte == 3) {
 268             out.writeInt(offsetBefore.getTotalSeconds());
 269         }
 270         if (afterByte == 3) {
 271             out.writeInt(offsetAfter.getTotalSeconds());
 272         }
 273     }
 274 
 275     /**
 276      * Checks if this set of rules equals another.
 277      * <p>
 278      * Two rule sets are equal if they will always result in the same output
 279      * for any given input instant or local date-time.
 280      * Rules from two different groups may return false even if they are in fact the same.
 281      * <p>
 282      * This definition should result in implementations comparing their entire state.
 283      *
 284      * @param otherRules  the other rules, null returns false
 285      * @return true if this rules is the same as that specified
 286      */
 287     @Override
 288     public boolean equals(Object otherRules) {
 289         if (this == otherRules) {
 290            return true;
 291         }
 292         if (otherRules instanceof ZoneRules) {
 293             ZoneRules other = (ZoneRules) otherRules;
 294             return Arrays.equals(standardTransitions, other.standardTransitions) &&
 295                     Arrays.equals(standardOffsets, other.standardOffsets) &&
 296                     Arrays.equals(savingsInstantTransitions, other.savingsInstantTransitions) &&
 297                     Arrays.equals(wallOffsets, other.wallOffsets) &&
 298                     Arrays.equals(lastRules, other.lastRules);
 299         }
 300         return false;
 301     }
 302 
 303     /**
 304      * Returns a suitable hash code given the definition of {@code #equals}.
 305      *
 306      * @return the hash code
 307      */
 308     @Override
 309     public int hashCode() {
 310         return Arrays.hashCode(standardTransitions) ^
 311                 Arrays.hashCode(standardOffsets) ^
 312                 Arrays.hashCode(savingsInstantTransitions) ^
 313                 Arrays.hashCode(wallOffsets) ^
 314                 Arrays.hashCode(lastRules);
 315     }
 316 
 317 }