1 /*
   2  * Copyright (c) 2013, 2019, 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) 2013, 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.chrono;
  58 
  59 import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
  60 import static java.time.temporal.ChronoUnit.DAYS;
  61 import static java.time.temporal.ChronoUnit.MONTHS;
  62 import static java.time.temporal.ChronoUnit.YEARS;
  63 
  64 import java.io.DataInput;
  65 import java.io.DataOutput;
  66 import java.io.IOException;
  67 import java.io.InvalidObjectException;
  68 import java.io.ObjectInputStream;
  69 import java.io.ObjectStreamException;
  70 import java.io.Serializable;
  71 import java.time.DateTimeException;
  72 import java.time.temporal.ChronoUnit;
  73 import java.time.temporal.Temporal;
  74 import java.time.temporal.TemporalAccessor;
  75 import java.time.temporal.TemporalAmount;
  76 import java.time.temporal.TemporalQueries;
  77 import java.time.temporal.TemporalUnit;
  78 import java.time.temporal.UnsupportedTemporalTypeException;
  79 import java.time.temporal.ValueRange;
  80 import java.util.List;
  81 import java.util.Objects;
  82 
  83 /**
  84  * A period expressed in terms of a standard year-month-day calendar system.
  85  * <p>
  86  * This class is used by applications seeking to handle dates in non-ISO calendar systems.
  87  * For example, the Japanese, Minguo, Thai Buddhist and others.
  88  *
  89  * @implSpec
  90  * This class is immutable nad thread-safe.
  91  *
  92  * @since 1.8
  93  */
  94 final class ChronoPeriodImpl
  95         implements ChronoPeriod, Serializable {
  96     // this class is only used by JDK chronology implementations and makes assumptions based on that fact
  97 
  98     /**
  99      * Serialization version.
 100      */
 101     @java.io.Serial
 102     private static final long serialVersionUID = 57387258289L;
 103 
 104     /**
 105      * The set of supported units.
 106      */
 107     private static final List<TemporalUnit> SUPPORTED_UNITS = List.of(YEARS, MONTHS, DAYS);
 108 
 109     /**
 110      * The chronology.
 111      */
 112     @SuppressWarnings("serial") // Not statically typed as Serializable
 113     private final Chronology chrono;
 114     /**
 115      * The number of years.
 116      */
 117     final int years;
 118     /**
 119      * The number of months.
 120      */
 121     final int months;
 122     /**
 123      * The number of days.
 124      */
 125     final int days;
 126 
 127     /**
 128      * Creates an instance.
 129      */
 130     ChronoPeriodImpl(Chronology chrono, int years, int months, int days) {
 131         Objects.requireNonNull(chrono, "chrono");
 132         this.chrono = chrono;
 133         this.years = years;
 134         this.months = months;
 135         this.days = days;
 136     }
 137 
 138     //-----------------------------------------------------------------------
 139     @Override
 140     public long get(TemporalUnit unit) {
 141         if (unit == ChronoUnit.YEARS) {
 142             return years;
 143         } else if (unit == ChronoUnit.MONTHS) {
 144             return months;
 145         } else if (unit == ChronoUnit.DAYS) {
 146             return days;
 147         } else {
 148             throw new UnsupportedTemporalTypeException("Unsupported unit: " + unit);
 149         }
 150     }
 151 
 152     @Override
 153     public List<TemporalUnit> getUnits() {
 154         return ChronoPeriodImpl.SUPPORTED_UNITS;
 155     }
 156 
 157     @Override
 158     public Chronology getChronology() {
 159         return chrono;
 160     }
 161 
 162     //-----------------------------------------------------------------------
 163     @Override
 164     public boolean isZero() {
 165         return years == 0 && months == 0 && days == 0;
 166     }
 167 
 168     @Override
 169     public boolean isNegative() {
 170         return years < 0 || months < 0 || days < 0;
 171     }
 172 
 173     //-----------------------------------------------------------------------
 174     @Override
 175     public ChronoPeriod plus(TemporalAmount amountToAdd) {
 176         ChronoPeriodImpl amount = validateAmount(amountToAdd);
 177         return new ChronoPeriodImpl(
 178                 chrono,
 179                 Math.addExact(years, amount.years),
 180                 Math.addExact(months, amount.months),
 181                 Math.addExact(days, amount.days));
 182     }
 183 
 184     @Override
 185     public ChronoPeriod minus(TemporalAmount amountToSubtract) {
 186         ChronoPeriodImpl amount = validateAmount(amountToSubtract);
 187         return new ChronoPeriodImpl(
 188                 chrono,
 189                 Math.subtractExact(years, amount.years),
 190                 Math.subtractExact(months, amount.months),
 191                 Math.subtractExact(days, amount.days));
 192     }
 193 
 194     /**
 195      * Obtains an instance of {@code ChronoPeriodImpl} from a temporal amount.
 196      *
 197      * @param amount  the temporal amount to convert, not null
 198      * @return the period, not null
 199      */
 200     private ChronoPeriodImpl validateAmount(TemporalAmount amount) {
 201         Objects.requireNonNull(amount, "amount");
 202         if (amount instanceof ChronoPeriodImpl == false) {
 203             throw new DateTimeException("Unable to obtain ChronoPeriod from TemporalAmount: " + amount.getClass());
 204         }
 205         ChronoPeriodImpl period = (ChronoPeriodImpl) amount;
 206         if (chrono.equals(period.getChronology()) == false) {
 207             throw new ClassCastException("Chronology mismatch, expected: " + chrono.getId() + ", actual: " + period.getChronology().getId());
 208         }
 209         return period;
 210     }
 211 
 212     //-----------------------------------------------------------------------
 213     @Override
 214     public ChronoPeriod multipliedBy(int scalar) {
 215         if (this.isZero() || scalar == 1) {
 216             return this;
 217         }
 218         return new ChronoPeriodImpl(
 219                 chrono,
 220                 Math.multiplyExact(years, scalar),
 221                 Math.multiplyExact(months, scalar),
 222                 Math.multiplyExact(days, scalar));
 223     }
 224 
 225     //-----------------------------------------------------------------------
 226     @Override
 227     public ChronoPeriod normalized() {
 228         long monthRange = monthRange();
 229         if (monthRange > 0) {
 230             long totalMonths = years * monthRange + months;
 231             long splitYears = totalMonths / monthRange;
 232             int splitMonths = (int) (totalMonths % monthRange);  // no overflow
 233             if (splitYears == years && splitMonths == months) {
 234                 return this;
 235             }
 236             return new ChronoPeriodImpl(chrono, Math.toIntExact(splitYears), splitMonths, days);
 237 
 238         }
 239         return this;
 240     }
 241 
 242     /**
 243      * Calculates the range of months.
 244      *
 245      * @return the month range, -1 if not fixed range
 246      */
 247     private long monthRange() {
 248         ValueRange startRange = chrono.range(MONTH_OF_YEAR);
 249         if (startRange.isFixed() && startRange.isIntValue()) {
 250             return startRange.getMaximum() - startRange.getMinimum() + 1;
 251         }
 252         return -1;
 253     }
 254 
 255     //-------------------------------------------------------------------------
 256     @Override
 257     public Temporal addTo(Temporal temporal) {
 258         validateChrono(temporal);
 259         if (months == 0) {
 260             if (years != 0) {
 261                 temporal = temporal.plus(years, YEARS);
 262             }
 263         } else {
 264             long monthRange = monthRange();
 265             if (monthRange > 0) {
 266                 temporal = temporal.plus(years * monthRange + months, MONTHS);
 267             } else {
 268                 if (years != 0) {
 269                     temporal = temporal.plus(years, YEARS);
 270                 }
 271                 temporal = temporal.plus(months, MONTHS);
 272             }
 273         }
 274         if (days != 0) {
 275             temporal = temporal.plus(days, DAYS);
 276         }
 277         return temporal;
 278     }
 279 
 280 
 281 
 282     @Override
 283     public Temporal subtractFrom(Temporal temporal) {
 284         validateChrono(temporal);
 285         if (months == 0) {
 286             if (years != 0) {
 287                 temporal = temporal.minus(years, YEARS);
 288             }
 289         } else {
 290             long monthRange = monthRange();
 291             if (monthRange > 0) {
 292                 temporal = temporal.minus(years * monthRange + months, MONTHS);
 293             } else {
 294                 if (years != 0) {
 295                     temporal = temporal.minus(years, YEARS);
 296                 }
 297                 temporal = temporal.minus(months, MONTHS);
 298             }
 299         }
 300         if (days != 0) {
 301             temporal = temporal.minus(days, DAYS);
 302         }
 303         return temporal;
 304     }
 305 
 306     /**
 307      * Validates that the temporal has the correct chronology.
 308      */
 309     private void validateChrono(TemporalAccessor temporal) {
 310         Objects.requireNonNull(temporal, "temporal");
 311         Chronology temporalChrono = temporal.query(TemporalQueries.chronology());
 312         if (temporalChrono != null && chrono.equals(temporalChrono) == false) {
 313             throw new DateTimeException("Chronology mismatch, expected: " + chrono.getId() + ", actual: " + temporalChrono.getId());
 314         }
 315     }
 316 
 317     //-----------------------------------------------------------------------
 318     @Override
 319     public boolean equals(Object obj) {
 320         if (this == obj) {
 321             return true;
 322         }
 323         if (obj instanceof ChronoPeriodImpl) {
 324             ChronoPeriodImpl other = (ChronoPeriodImpl) obj;
 325             return years == other.years && months == other.months &&
 326                     days == other.days && chrono.equals(other.chrono);
 327         }
 328         return false;
 329     }
 330 
 331     @Override
 332     public int hashCode() {
 333         return (years + Integer.rotateLeft(months, 8) + Integer.rotateLeft(days, 16)) ^ chrono.hashCode();
 334     }
 335 
 336     //-----------------------------------------------------------------------
 337     @Override
 338     public String toString() {
 339         if (isZero()) {
 340             return getChronology().toString() + " P0D";
 341         } else {
 342             StringBuilder buf = new StringBuilder();
 343             buf.append(getChronology().toString()).append(' ').append('P');
 344             if (years != 0) {
 345                 buf.append(years).append('Y');
 346             }
 347             if (months != 0) {
 348                 buf.append(months).append('M');
 349             }
 350             if (days != 0) {
 351                 buf.append(days).append('D');
 352             }
 353             return buf.toString();
 354         }
 355     }
 356 
 357     //-----------------------------------------------------------------------
 358     /**
 359      * Writes the Chronology using a
 360      * <a href="{@docRoot}/serialized-form.html#java.time.chrono.Ser">dedicated serialized form</a>.
 361      * <pre>
 362      *  out.writeByte(12);  // identifies this as a ChronoPeriodImpl
 363      *  out.writeUTF(getId());  // the chronology
 364      *  out.writeInt(years);
 365      *  out.writeInt(months);
 366      *  out.writeInt(days);
 367      * </pre>
 368      *
 369      * @return the instance of {@code Ser}, not null
 370      */
 371     @java.io.Serial
 372     protected Object writeReplace() {
 373         return new Ser(Ser.CHRONO_PERIOD_TYPE, this);
 374     }
 375 
 376     /**
 377      * Defend against malicious streams.
 378      *
 379      * @param s the stream to read
 380      * @throws InvalidObjectException always
 381      */
 382     @java.io.Serial
 383     private void readObject(ObjectInputStream s) throws ObjectStreamException {
 384         throw new InvalidObjectException("Deserialization via serialization delegate");
 385     }
 386 
 387     void writeExternal(DataOutput out) throws IOException {
 388         out.writeUTF(chrono.getId());
 389         out.writeInt(years);
 390         out.writeInt(months);
 391         out.writeInt(days);
 392     }
 393 
 394     static ChronoPeriodImpl readExternal(DataInput in) throws IOException {
 395         Chronology chrono = Chronology.of(in.readUTF());
 396         int years = in.readInt();
 397         int months = in.readInt();
 398         int days = in.readInt();
 399         return new ChronoPeriodImpl(chrono, years, months, days);
 400     }
 401 
 402 }