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