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) 2007-2012, 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 java.time;
63
64 import static java.time.LocalTime.NANOS_PER_SECOND;
65 import static java.time.LocalTime.SECONDS_PER_DAY;
66 import static java.time.LocalTime.SECONDS_PER_HOUR;
67 import static java.time.LocalTime.SECONDS_PER_MINUTE;
68 import static java.time.temporal.ChronoField.NANO_OF_SECOND;
69 import static java.time.temporal.ChronoUnit.DAYS;
70 import static java.time.temporal.ChronoUnit.NANOS;
71 import static java.time.temporal.ChronoUnit.SECONDS;
72
73 import java.io.DataInput;
74 import java.io.DataOutput;
75 import java.io.IOException;
76 import java.io.InvalidObjectException;
77 import java.io.ObjectStreamException;
78 import java.io.Serializable;
79 import java.math.BigDecimal;
80 import java.math.BigInteger;
81 import java.math.RoundingMode;
82 import java.time.format.DateTimeParseException;
83 import java.time.temporal.ChronoField;
84 import java.time.temporal.ChronoUnit;
85 import java.time.temporal.Temporal;
86 import java.time.temporal.TemporalAmount;
87 import java.time.temporal.TemporalUnit;
88 import java.util.Arrays;
89 import java.util.Collections;
90 import java.util.List;
91 import java.util.Objects;
92 import java.util.regex.Matcher;
93 import java.util.regex.Pattern;
94
95 /**
96 * A time-based amount of time, such as '34.5 seconds'.
97 * <p>
98 * This class models a quantity or amount of time in terms of seconds and nanoseconds.
99 * It can be accessed using other duration-based units, such as minutes and hours.
100 * In addition, the {@link ChronoUnit#DAYS DAYS} unit can be used and is treated as
101 * exactly equal to 24 hours, thus ignoring daylight savings effects.
102 * See {@link Period} for the date-based equivalent to this class.
103 * <p>
104 * A physical duration could be of infinite length.
105 * For practicality, the duration is stored with constraints similar to {@link Instant}.
106 * The duration uses nanosecond resolution with a maximum value of the seconds that can
107 * be held in a {@code long}. This is greater than the current estimated age of the universe.
108 * <p>
109 * The range of a duration requires the storage of a number larger than a {@code long}.
110 * To achieve this, the class stores a {@code long} representing seconds and an {@code int}
111 * representing nanosecond-of-second, which will always be between 0 and 999,999,999.
112 * The model is of a directed duration, meaning that the duration may be negative.
113 * <p>
114 * The duration is measured in "seconds", but these are not necessarily identical to
115 * the scientific "SI second" definition based on atomic clocks.
116 * This difference only impacts durations measured near a leap-second and should not affect
117 * most applications.
118 * See {@link Instant} for a discussion as to the meaning of the second and time-scales.
119 *
120 * <h3>Specification for implementors</h3>
121 * This class is immutable and thread-safe.
122 *
123 * @since 1.8
124 */
125 public final class Duration
126 implements TemporalAmount, Comparable<Duration>, Serializable {
127
128 /**
129 * Constant for a duration of zero.
130 */
131 public static final Duration ZERO = new Duration(0, 0);
132 /**
133 * Serialization version.
134 */
135 private static final long serialVersionUID = 3078945930695997490L;
136 /**
137 * Constant for nanos per second.
138 */
139 private static final BigInteger BI_NANOS_PER_SECOND = BigInteger.valueOf(NANOS_PER_SECOND);
140 /**
141 * The pattern for parsing.
142 */
143 private final static Pattern PATTERN =
144 Pattern.compile("([-+]?)P(?:([-+]?[0-9]+)D)?" +
145 "(T(?:([-+]?[0-9]+)H)?(?:([-+]?[0-9]+)M)?(?:([-+]?[0-9]+)(?:[.,]([0-9]{0,9}))?S)?)?",
146 Pattern.CASE_INSENSITIVE);
147
148 /**
149 * The number of seconds in the duration.
150 */
151 private final long seconds;
152 /**
153 * The number of nanoseconds in the duration, expressed as a fraction of the
154 * number of seconds. This is always positive, and never exceeds 999,999,999.
155 */
156 private final int nanos;
157
158 //-----------------------------------------------------------------------
159 /**
160 * Obtains a {@code Duration} representing a number of standard 24 hour days.
161 * <p>
162 * The seconds are calculated based on the standard definition of a day,
163 * where each day is 86400 seconds which implies a 24 hour day.
164 * The nanosecond in second field is set to zero.
165 *
166 * @param days the number of days, positive or negative
167 * @return a {@code Duration}, not null
168 * @throws ArithmeticException if the input days exceeds the capacity of {@code Duration}
169 */
170 public static Duration ofDays(long days) {
171 return create(Math.multiplyExact(days, SECONDS_PER_DAY), 0);
172 }
173
174 /**
175 * Obtains a {@code Duration} representing a number of standard hours.
176 * <p>
177 * The seconds are calculated based on the standard definition of an hour,
178 * where each hour is 3600 seconds.
179 * The nanosecond in second field is set to zero.
180 *
181 * @param hours the number of hours, positive or negative
182 * @return a {@code Duration}, not null
183 * @throws ArithmeticException if the input hours exceeds the capacity of {@code Duration}
184 */
185 public static Duration ofHours(long hours) {
186 return create(Math.multiplyExact(hours, SECONDS_PER_HOUR), 0);
187 }
188
189 /**
190 * Obtains a {@code Duration} representing a number of standard minutes.
191 * <p>
192 * The seconds are calculated based on the standard definition of a minute,
193 * where each minute is 60 seconds.
194 * The nanosecond in second field is set to zero.
195 *
196 * @param minutes the number of minutes, positive or negative
197 * @return a {@code Duration}, not null
198 * @throws ArithmeticException if the input minutes exceeds the capacity of {@code Duration}
199 */
200 public static Duration ofMinutes(long minutes) {
201 return create(Math.multiplyExact(minutes, SECONDS_PER_MINUTE), 0);
202 }
203
204 //-----------------------------------------------------------------------
205 /**
206 * Obtains a {@code Duration} representing a number of seconds.
207 * <p>
208 * The nanosecond in second field is set to zero.
209 *
210 * @param seconds the number of seconds, positive or negative
211 * @return a {@code Duration}, not null
212 */
213 public static Duration ofSeconds(long seconds) {
214 return create(seconds, 0);
215 }
216
217 /**
218 * Obtains a {@code Duration} representing a number of seconds and an
219 * adjustment in nanoseconds.
220 * <p>
221 * This method allows an arbitrary number of nanoseconds to be passed in.
222 * The factory will alter the values of the second and nanosecond in order
223 * to ensure that the stored nanosecond is in the range 0 to 999,999,999.
224 * For example, the following will result in the exactly the same duration:
225 * <pre>
226 * Duration.ofSeconds(3, 1);
227 * Duration.ofSeconds(4, -999_999_999);
228 * Duration.ofSeconds(2, 1000_000_001);
229 * </pre>
230 *
231 * @param seconds the number of seconds, positive or negative
232 * @param nanoAdjustment the nanosecond adjustment to the number of seconds, positive or negative
233 * @return a {@code Duration}, not null
234 * @throws ArithmeticException if the adjustment causes the seconds to exceed the capacity of {@code Duration}
235 */
236 public static Duration ofSeconds(long seconds, long nanoAdjustment) {
237 long secs = Math.addExact(seconds, Math.floorDiv(nanoAdjustment, NANOS_PER_SECOND));
238 int nos = (int) Math.floorMod(nanoAdjustment, NANOS_PER_SECOND);
239 return create(secs, nos);
240 }
241
242 //-----------------------------------------------------------------------
243 /**
244 * Obtains a {@code Duration} representing a number of milliseconds.
245 * <p>
246 * The seconds and nanoseconds are extracted from the specified milliseconds.
247 *
248 * @param millis the number of milliseconds, positive or negative
249 * @return a {@code Duration}, not null
250 */
251 public static Duration ofMillis(long millis) {
252 long secs = millis / 1000;
253 int mos = (int) (millis % 1000);
254 if (mos < 0) {
255 mos += 1000;
256 secs--;
257 }
258 return create(secs, mos * 1000_000);
259 }
260
261 //-----------------------------------------------------------------------
262 /**
263 * Obtains a {@code Duration} representing a number of nanoseconds.
264 * <p>
265 * The seconds and nanoseconds are extracted from the specified nanoseconds.
266 *
267 * @param nanos the number of nanoseconds, positive or negative
268 * @return a {@code Duration}, not null
269 */
270 public static Duration ofNanos(long nanos) {
271 long secs = nanos / NANOS_PER_SECOND;
272 int nos = (int) (nanos % NANOS_PER_SECOND);
273 if (nos < 0) {
274 nos += NANOS_PER_SECOND;
275 secs--;
276 }
277 return create(secs, nos);
278 }
279
280 //-----------------------------------------------------------------------
281 /**
282 * Obtains a {@code Duration} representing an amount in the specified unit.
283 * <p>
284 * The parameters represent the two parts of a phrase like '6 Hours'. For example:
285 * <pre>
286 * Duration.of(3, SECONDS);
287 * Duration.of(465, HOURS);
288 * </pre>
289 * Only a subset of units are accepted by this method.
290 * The unit must either have an {@linkplain TemporalUnit#isDurationEstimated() exact duration} or
291 * be {@link ChronoUnit#DAYS} which is treated as 24 hours. Other units throw an exception.
292 *
293 * @param amount the amount of the duration, measured in terms of the unit, positive or negative
294 * @param unit the unit that the duration is measured in, must have an exact duration, not null
295 * @return a {@code Duration}, not null
296 * @throws DateTimeException if the period unit has an estimated duration
297 * @throws ArithmeticException if a numeric overflow occurs
298 */
299 public static Duration of(long amount, TemporalUnit unit) {
300 return ZERO.plus(amount, unit);
301 }
302
303 //-----------------------------------------------------------------------
304 /**
305 * Obtains a {@code Duration} representing the duration between two instants.
306 * <p>
307 * This calculates the duration between two temporal objects of the same type.
308 * The difference in seconds is calculated using
309 * {@link Temporal#periodUntil(Temporal, TemporalUnit)}.
310 * The difference in nanoseconds is calculated using by querying the
311 * {@link ChronoField#NANO_OF_SECOND NANO_OF_SECOND} field.
312 * <p>
313 * The result of this method can be a negative period if the end is before the start.
314 * To guarantee to obtain a positive duration call {@link #abs()} on the result.
315 *
316 * @param startInclusive the start instant, inclusive, not null
317 * @param endExclusive the end instant, exclusive, not null
318 * @return a {@code Duration}, not null
319 * @throws ArithmeticException if the calculation exceeds the capacity of {@code Duration}
320 */
321 public static Duration between(Temporal startInclusive, Temporal endExclusive) {
322 long secs = startInclusive.periodUntil(endExclusive, SECONDS);
323 long nanos;
324 try {
325 nanos = endExclusive.getLong(NANO_OF_SECOND) - startInclusive.getLong(NANO_OF_SECOND);
326 } catch (DateTimeException ex) {
327 nanos = 0;
328 }
329 return ofSeconds(secs, nanos);
330 }
331
332 //-----------------------------------------------------------------------
333 /**
334 * Obtains a {@code Duration} from a text string such as {@code PnDTnHnMn.nS}.
335 * <p>
336 * This will parse a textual representation of a duration, including the
337 * string produced by {@code toString()}. The formats accepted are based
338 * on the ISO-8601 duration format {@code PnDTnHnMn.nS} with days
339 * considered to be exactly 24 hours.
340 * <p>
341 * The string starts with an optional sign, denoted by the ASCII negative
342 * or positive symbol. If negative, the whole period is negated.
343 * The ASCII letter "P" is next in upper or lower case.
344 * There are then four sections, each consisting of a number and a suffix.
345 * The sections have suffixes in ASCII of "D", "H", "M" and "S" for
346 * days, hours, minutes and seconds, accepted in upper or lower case.
347 * The suffixes must occur in order. The ASCII letter "T" must occur before
348 * the first occurrence, if any, of an hour, minute or second section.
349 * At least one of the four sections must be present, and if "T" is present
350 * there must be at least one section after the "T".
351 * The number part of each section must consist of one or more ASCII digits.
352 * The number may be prefixed by the ASCII negative or positive symbol.
353 * The number of days, hours and minutes must parse to an {@code long}.
354 * The number of seconds must parse to an {@code long} with optional fraction.
355 * The decimal point may be either a dot or a comma.
356 * The fractional part may have from zero to 9 digits.
357 * <p>
358 * The leading plus/minus sign, and negative values for other units are
359 * not part of the ISO-8601 standard.
360 * <p>
361 * Examples:
362 * <pre>
363 * "PT20.345S" -> parses as "20.345 seconds"
364 * "PT15M" -> parses as "15 minutes" (where a minute is 60 seconds)
365 * "PT10H" -> parses as "10 hours" (where an hour is 3600 seconds)
366 * "P2D" -> parses as "2 days" (where a day is 24 hours or 86400 seconds)
367 * "P2DT3H4M" -> parses as "2 days, 3 hours and 4 minutes"
368 * "P-6H3M" -> parses as "-6 hours and +3 minutes"
369 * "-P6H3M" -> parses as "-6 hours and -3 minutes"
370 * "-P-6H+3M" -> parses as "+6 hours and -3 minutes"
371 * </pre>
372 *
373 * @param text the text to parse, not null
374 * @return the parsed duration, not null
375 * @throws DateTimeParseException if the text cannot be parsed to a duration
376 */
377 public static Duration parse(CharSequence text) {
378 Objects.requireNonNull(text, "text");
379 Matcher matcher = PATTERN.matcher(text);
380 if (matcher.matches()) {
381 // check for letter T but no time sections
382 if ("T".equals(matcher.group(3)) == false) {
383 boolean negate = "-".equals(matcher.group(1));
384 String dayMatch = matcher.group(2);
385 String hourMatch = matcher.group(4);
386 String minuteMatch = matcher.group(5);
387 String secondMatch = matcher.group(6);
388 String fractionMatch = matcher.group(7);
389 if (dayMatch != null || hourMatch != null || minuteMatch != null || secondMatch != null) {
390 long daysAsSecs = parseNumber(text, dayMatch, SECONDS_PER_DAY, "days");
391 long hoursAsSecs = parseNumber(text, hourMatch, SECONDS_PER_HOUR, "hours");
392 long minsAsSecs = parseNumber(text, minuteMatch, SECONDS_PER_MINUTE, "minutes");
393 long seconds = parseNumber(text, secondMatch, 1, "seconds");
394 int nanos = parseFraction(text, fractionMatch, seconds < 0 ? -1 : 1);
395 try {
396 return create(negate, daysAsSecs, hoursAsSecs, minsAsSecs, seconds, nanos);
397 } catch (ArithmeticException ex) {
398 throw (DateTimeParseException) new DateTimeParseException("Text cannot be parsed to a Duration: overflow", text, 0).initCause(ex);
399 }
400 }
401 }
402 }
403 throw new DateTimeParseException("Text cannot be parsed to a Duration", text, 0);
404 }
405
406 private static long parseNumber(CharSequence text, String parsed, int multiplier, String errorText) {
407 // regex limits to [-+]?[0-9]+
408 if (parsed == null) {
409 return 0;
410 }
411 try {
412 long val = Long.parseLong(parsed);
413 return Math.multiplyExact(val, multiplier);
414 } catch (NumberFormatException | ArithmeticException ex) {
415 throw (DateTimeParseException) new DateTimeParseException("Text cannot be parsed to a Duration: " + errorText, text, 0).initCause(ex);
416 }
417 }
418
419 private static int parseFraction(CharSequence text, String parsed, int negate) {
420 // regex limits to [0-9]{0,9}
421 if (parsed == null || parsed.length() == 0) {
422 return 0;
423 }
424 try {
425 parsed = (parsed + "000000000").substring(0, 9);
426 return Integer.parseInt(parsed) * negate;
427 } catch (NumberFormatException | ArithmeticException ex) {
428 throw (DateTimeParseException) new DateTimeParseException("Text cannot be parsed to a Duration: fraction", text, 0).initCause(ex);
429 }
430 }
431
432 private static Duration create(boolean negate, long daysAsSecs, long hoursAsSecs, long minsAsSecs, long secs, int nanos) {
433 long seconds = Math.addExact(daysAsSecs, Math.addExact(hoursAsSecs, Math.addExact(minsAsSecs, secs)));
434 if (negate) {
435 return ofSeconds(seconds, nanos).negated();
436 }
437 return ofSeconds(seconds, nanos);
438 }
439
440 //-----------------------------------------------------------------------
441 /**
442 * Obtains an instance of {@code Duration} using seconds and nanoseconds.
443 *
444 * @param seconds the length of the duration in seconds, positive or negative
445 * @param nanoAdjustment the nanosecond adjustment within the second, from 0 to 999,999,999
446 */
447 private static Duration create(long seconds, int nanoAdjustment) {
448 if ((seconds | nanoAdjustment) == 0) {
449 return ZERO;
450 }
451 return new Duration(seconds, nanoAdjustment);
452 }
453
454 /**
455 * Constructs an instance of {@code Duration} using seconds and nanoseconds.
456 *
457 * @param seconds the length of the duration in seconds, positive or negative
458 * @param nanos the nanoseconds within the second, from 0 to 999,999,999
459 */
460 private Duration(long seconds, int nanos) {
461 super();
462 this.seconds = seconds;
463 this.nanos = nanos;
464 }
465
466 //-----------------------------------------------------------------------
467 /**
468 * Gets the value of the requested unit.
469 * <p>
470 * This returns a value for each of the two supported units,
471 * {@link ChronoUnit#SECONDS SECONDS} and {@link ChronoUnit#NANOS NANOS}.
472 * All other units throw an exception.
473 *
474 * @param unit the {@code TemporalUnit} for which to return the value
475 * @return the long value of the unit
476 * @throws DateTimeException if the unit is not supported
477 */
478 @Override
479 public long get(TemporalUnit unit) {
480 if (unit == SECONDS) {
481 return seconds;
482 } else if (unit == NANOS) {
483 return nanos;
484 } else {
485 throw new DateTimeException("Unsupported unit: " + unit.getName());
486 }
487 }
488
489 /**
490 * Gets the set of units supported by this duration.
491 * <p>
492 * The supported units are {@link ChronoUnit#SECONDS SECONDS},
493 * and {@link ChronoUnit#NANOS NANOS}.
494 * They are returned in the order seconds, nanos.
495 * <p>
496 * This set can be used in conjunction with {@link #get(TemporalUnit)}
497 * to access the entire state of the period.
498 *
499 * @return a list containing the seconds and nanos units, not null
500 */
501 @Override
502 public List<TemporalUnit> getUnits() {
503 return DurationUnits.UNITS;
504 }
505
506 /**
507 * Private class to delay initialization of this list until needed.
508 * The circular dependency between Duration and ChronoUnit prevents
509 * the simple initialization in Duration.
510 */
511 private static class DurationUnits {
512 final static List<TemporalUnit> UNITS =
513 Collections.unmodifiableList(Arrays.<TemporalUnit>asList(SECONDS, NANOS));
514 }
515
516 //-----------------------------------------------------------------------
517 /**
518 * Checks if this duration is zero length.
519 * <p>
520 * A {@code Duration} represents a directed distance between two points on
521 * the time-line and can therefore be positive, zero or negative.
522 * This method checks whether the length is zero.
523 *
524 * @return true if this duration has a total length equal to zero
525 */
526 public boolean isZero() {
527 return (seconds | nanos) == 0;
528 }
529
530 /**
531 * Checks if this duration is negative, excluding zero.
532 * <p>
533 * A {@code Duration} represents a directed distance between two points on
534 * the time-line and can therefore be positive, zero or negative.
535 * This method checks whether the length is less than zero.
536 *
537 * @return true if this duration has a total length less than zero
538 */
539 public boolean isNegative() {
540 return seconds < 0;
541 }
542
543 //-----------------------------------------------------------------------
544 /**
545 * Gets the number of seconds in this duration.
546 * <p>
547 * The length of the duration is stored using two fields - seconds and nanoseconds.
548 * The nanoseconds part is a value from 0 to 999,999,999 that is an adjustment to
549 * the length in seconds.
550 * The total duration is defined by calling this method and {@link #getNano()}.
551 * <p>
552 * A {@code Duration} represents a directed distance between two points on the time-line.
553 * A negative duration is expressed by the negative sign of the seconds part.
554 * A duration of -1 nanosecond is stored as -1 seconds plus 999,999,999 nanoseconds.
555 *
556 * @return the whole seconds part of the length of the duration, positive or negative
557 */
558 public long getSeconds() {
559 return seconds;
560 }
561
562 /**
563 * Gets the number of nanoseconds within the second in this duration.
564 * <p>
565 * The length of the duration is stored using two fields - seconds and nanoseconds.
566 * The nanoseconds part is a value from 0 to 999,999,999 that is an adjustment to
567 * the length in seconds.
568 * The total duration is defined by calling this method and {@link #getSeconds()}.
569 * <p>
570 * A {@code Duration} represents a directed distance between two points on the time-line.
571 * A negative duration is expressed by the negative sign of the seconds part.
572 * A duration of -1 nanosecond is stored as -1 seconds plus 999,999,999 nanoseconds.
573 *
574 * @return the nanoseconds within the second part of the length of the duration, from 0 to 999,999,999
575 */
576 public int getNano() {
577 return nanos;
578 }
579
580 //-----------------------------------------------------------------------
581 /**
582 * Returns a copy of this duration with the specified amount of seconds.
583 * <p>
584 * This returns a duration with the specified seconds, retaining the
585 * nano-of-second part of this duration.
586 * <p>
587 * This instance is immutable and unaffected by this method call.
588 *
589 * @param seconds the seconds to represent, may be negative
590 * @return a {@code Duration} based on this period with the requested seconds, not null
591 */
592 public Duration withSeconds(long seconds) {
593 return create(seconds, nanos);
594 }
595
596 /**
597 * Returns a copy of this duration with the specified nano-of-second.
598 * <p>
599 * This returns a duration with the specified nano-of-second, retaining the
600 * seconds part of this duration.
601 * <p>
602 * This instance is immutable and unaffected by this method call.
603 *
604 * @param nanoOfSecond the nano-of-second to represent, from 0 to 999,999,999
605 * @return a {@code Duration} based on this period with the requested nano-of-second, not null
606 * @throws DateTimeException if the nano-of-second is invalid
607 */
608 public Duration withNanos(int nanoOfSecond) {
609 NANO_OF_SECOND.checkValidIntValue(nanoOfSecond);
610 return create(seconds, nanoOfSecond);
611 }
612
613 //-----------------------------------------------------------------------
614 /**
615 * Returns a copy of this duration with the specified duration added.
616 * <p>
617 * This instance is immutable and unaffected by this method call.
618 *
619 * @param duration the duration to add, positive or negative, not null
620 * @return a {@code Duration} based on this duration with the specified duration added, not null
621 * @throws ArithmeticException if numeric overflow occurs
622 */
623 public Duration plus(Duration duration) {
624 return plus(duration.getSeconds(), duration.getNano());
625 }
626
627 /**
628 * Returns a copy of this duration with the specified duration added.
629 * <p>
630 * The duration amount is measured in terms of the specified unit.
631 * Only a subset of units are accepted by this method.
632 * The unit must either have an {@linkplain TemporalUnit#isDurationEstimated() exact duration} or
633 * be {@link ChronoUnit#DAYS} which is treated as 24 hours. Other units throw an exception.
634 * <p>
635 * This instance is immutable and unaffected by this method call.
636 *
637 * @param amountToAdd the amount of the period, measured in terms of the unit, positive or negative
638 * @param unit the unit that the period is measured in, must have an exact duration, not null
639 * @return a {@code Duration} based on this duration with the specified duration added, not null
640 * @throws ArithmeticException if numeric overflow occurs
641 */
642 public Duration plus(long amountToAdd, TemporalUnit unit) {
643 Objects.requireNonNull(unit, "unit");
644 if (unit == DAYS) {
645 return plus(Math.multiplyExact(amountToAdd, SECONDS_PER_DAY), 0);
646 }
647 if (unit.isDurationEstimated()) {
648 throw new DateTimeException("Unit must not have an estimated duration");
649 }
650 if (amountToAdd == 0) {
651 return this;
652 }
653 if (unit instanceof ChronoUnit) {
654 switch ((ChronoUnit) unit) {
655 case NANOS: return plusNanos(amountToAdd);
656 case MICROS: return plusSeconds((amountToAdd / (1000_000L * 1000)) * 1000).plusNanos((amountToAdd % (1000_000L * 1000)) * 1000);
657 case MILLIS: return plusMillis(amountToAdd);
658 case SECONDS: return plusSeconds(amountToAdd);
659 }
660 return plusSeconds(Math.multiplyExact(unit.getDuration().seconds, amountToAdd));
661 }
662 Duration duration = unit.getDuration().multipliedBy(amountToAdd);
663 return plusSeconds(duration.getSeconds()).plusNanos(duration.getNano());
664 }
665
666 //-----------------------------------------------------------------------
667 /**
668 * Returns a copy of this duration with the specified duration in standard 24 hour days added.
669 * <p>
670 * The number of days is multiplied by 86400 to obtain the number of seconds to add.
671 * This is based on the standard definition of a day as 24 hours.
672 * <p>
673 * This instance is immutable and unaffected by this method call.
674 *
675 * @param daysToAdd the days to add, positive or negative
676 * @return a {@code Duration} based on this duration with the specified days added, not null
677 * @throws ArithmeticException if numeric overflow occurs
678 */
679 public Duration plusDays(long daysToAdd) {
680 return plus(Math.multiplyExact(daysToAdd, SECONDS_PER_DAY), 0);
681 }
682
683 /**
684 * Returns a copy of this duration with the specified duration in hours added.
685 * <p>
686 * This instance is immutable and unaffected by this method call.
687 *
688 * @param hoursToAdd the hours to add, positive or negative
689 * @return a {@code Duration} based on this duration with the specified hours added, not null
690 * @throws ArithmeticException if numeric overflow occurs
691 */
692 public Duration plusHours(long hoursToAdd) {
693 return plus(Math.multiplyExact(hoursToAdd, SECONDS_PER_HOUR), 0);
694 }
695
696 /**
697 * Returns a copy of this duration with the specified duration in minutes added.
698 * <p>
699 * This instance is immutable and unaffected by this method call.
700 *
701 * @param minutesToAdd the minutes to add, positive or negative
702 * @return a {@code Duration} based on this duration with the specified minutes added, not null
703 * @throws ArithmeticException if numeric overflow occurs
704 */
705 public Duration plusMinutes(long minutesToAdd) {
706 return plus(Math.multiplyExact(minutesToAdd, SECONDS_PER_MINUTE), 0);
707 }
708
709 /**
710 * Returns a copy of this duration with the specified duration in seconds added.
711 * <p>
712 * This instance is immutable and unaffected by this method call.
713 *
714 * @param secondsToAdd the seconds to add, positive or negative
715 * @return a {@code Duration} based on this duration with the specified seconds added, not null
716 * @throws ArithmeticException if numeric overflow occurs
717 */
718 public Duration plusSeconds(long secondsToAdd) {
719 return plus(secondsToAdd, 0);
720 }
721
722 /**
723 * Returns a copy of this duration with the specified duration in milliseconds added.
724 * <p>
725 * This instance is immutable and unaffected by this method call.
726 *
727 * @param millisToAdd the milliseconds to add, positive or negative
728 * @return a {@code Duration} based on this duration with the specified milliseconds added, not null
729 * @throws ArithmeticException if numeric overflow occurs
730 */
731 public Duration plusMillis(long millisToAdd) {
732 return plus(millisToAdd / 1000, (millisToAdd % 1000) * 1000_000);
733 }
734
735 /**
736 * Returns a copy of this duration with the specified duration in nanoseconds added.
737 * <p>
738 * This instance is immutable and unaffected by this method call.
739 *
740 * @param nanosToAdd the nanoseconds to add, positive or negative
741 * @return a {@code Duration} based on this duration with the specified nanoseconds added, not null
742 * @throws ArithmeticException if numeric overflow occurs
743 */
744 public Duration plusNanos(long nanosToAdd) {
745 return plus(0, nanosToAdd);
746 }
747
748 /**
749 * Returns a copy of this duration with the specified duration added.
750 * <p>
751 * This instance is immutable and unaffected by this method call.
752 *
753 * @param secondsToAdd the seconds to add, positive or negative
754 * @param nanosToAdd the nanos to add, positive or negative
755 * @return a {@code Duration} based on this duration with the specified seconds added, not null
756 * @throws ArithmeticException if numeric overflow occurs
757 */
758 private Duration plus(long secondsToAdd, long nanosToAdd) {
759 if ((secondsToAdd | nanosToAdd) == 0) {
760 return this;
761 }
762 long epochSec = Math.addExact(seconds, secondsToAdd);
763 epochSec = Math.addExact(epochSec, nanosToAdd / NANOS_PER_SECOND);
764 nanosToAdd = nanosToAdd % NANOS_PER_SECOND;
765 long nanoAdjustment = nanos + nanosToAdd; // safe int+NANOS_PER_SECOND
766 return ofSeconds(epochSec, nanoAdjustment);
767 }
768
769 //-----------------------------------------------------------------------
770 /**
771 * Returns a copy of this duration with the specified duration subtracted.
772 * <p>
773 * This instance is immutable and unaffected by this method call.
774 *
775 * @param duration the duration to subtract, positive or negative, not null
776 * @return a {@code Duration} based on this duration with the specified duration subtracted, not null
777 * @throws ArithmeticException if numeric overflow occurs
778 */
779 public Duration minus(Duration duration) {
780 long secsToSubtract = duration.getSeconds();
781 int nanosToSubtract = duration.getNano();
782 if (secsToSubtract == Long.MIN_VALUE) {
783 return plus(Long.MAX_VALUE, -nanosToSubtract).plus(1, 0);
784 }
785 return plus(-secsToSubtract, -nanosToSubtract);
786 }
787
788 /**
789 * Returns a copy of this duration with the specified duration subtracted.
790 * <p>
791 * The duration amount is measured in terms of the specified unit.
792 * Only a subset of units are accepted by this method.
793 * The unit must either have an {@linkplain TemporalUnit#isDurationEstimated() exact duration} or
794 * be {@link ChronoUnit#DAYS} which is treated as 24 hours. Other units throw an exception.
795 * <p>
796 * This instance is immutable and unaffected by this method call.
797 *
798 * @param amountToSubtract the amount of the period, measured in terms of the unit, positive or negative
799 * @param unit the unit that the period is measured in, must have an exact duration, not null
800 * @return a {@code Duration} based on this duration with the specified duration subtracted, not null
801 * @throws ArithmeticException if numeric overflow occurs
802 */
803 public Duration minus(long amountToSubtract, TemporalUnit unit) {
804 return (amountToSubtract == Long.MIN_VALUE ? plus(Long.MAX_VALUE, unit).plus(1, unit) : plus(-amountToSubtract, unit));
805 }
806
807 //-----------------------------------------------------------------------
808 /**
809 * Returns a copy of this duration with the specified duration in standard 24 hour days subtracted.
810 * <p>
811 * The number of days is multiplied by 86400 to obtain the number of seconds to subtract.
812 * This is based on the standard definition of a day as 24 hours.
813 * <p>
814 * This instance is immutable and unaffected by this method call.
815 *
816 * @param daysToSubtract the days to subtract, positive or negative
817 * @return a {@code Duration} based on this duration with the specified days subtracted, not null
818 * @throws ArithmeticException if numeric overflow occurs
819 */
820 public Duration minusDays(long daysToSubtract) {
821 return (daysToSubtract == Long.MIN_VALUE ? plusDays(Long.MAX_VALUE).plusDays(1) : plusDays(-daysToSubtract));
822 }
823
824 /**
825 * Returns a copy of this duration with the specified duration in hours subtracted.
826 * <p>
827 * The number of hours is multiplied by 3600 to obtain the number of seconds to subtract.
828 * <p>
829 * This instance is immutable and unaffected by this method call.
830 *
831 * @param hoursToSubtract the hours to subtract, positive or negative
832 * @return a {@code Duration} based on this duration with the specified hours subtracted, not null
833 * @throws ArithmeticException if numeric overflow occurs
834 */
835 public Duration minusHours(long hoursToSubtract) {
836 return (hoursToSubtract == Long.MIN_VALUE ? plusHours(Long.MAX_VALUE).plusHours(1) : plusHours(-hoursToSubtract));
837 }
838
839 /**
840 * Returns a copy of this duration with the specified duration in minutes subtracted.
841 * <p>
842 * The number of hours is multiplied by 60 to obtain the number of seconds to subtract.
843 * <p>
844 * This instance is immutable and unaffected by this method call.
845 *
846 * @param minutesToSubtract the minutes to subtract, positive or negative
847 * @return a {@code Duration} based on this duration with the specified minutes subtracted, not null
848 * @throws ArithmeticException if numeric overflow occurs
849 */
850 public Duration minusMinutes(long minutesToSubtract) {
851 return (minutesToSubtract == Long.MIN_VALUE ? plusMinutes(Long.MAX_VALUE).plusMinutes(1) : plusMinutes(-minutesToSubtract));
852 }
853
854 /**
855 * Returns a copy of this duration with the specified duration in seconds subtracted.
856 * <p>
857 * This instance is immutable and unaffected by this method call.
858 *
859 * @param secondsToSubtract the seconds to subtract, positive or negative
860 * @return a {@code Duration} based on this duration with the specified seconds subtracted, not null
861 * @throws ArithmeticException if numeric overflow occurs
862 */
863 public Duration minusSeconds(long secondsToSubtract) {
864 return (secondsToSubtract == Long.MIN_VALUE ? plusSeconds(Long.MAX_VALUE).plusSeconds(1) : plusSeconds(-secondsToSubtract));
865 }
866
867 /**
868 * Returns a copy of this duration with the specified duration in milliseconds subtracted.
869 * <p>
870 * This instance is immutable and unaffected by this method call.
871 *
872 * @param millisToSubtract the milliseconds to subtract, positive or negative
873 * @return a {@code Duration} based on this duration with the specified milliseconds subtracted, not null
874 * @throws ArithmeticException if numeric overflow occurs
875 */
876 public Duration minusMillis(long millisToSubtract) {
877 return (millisToSubtract == Long.MIN_VALUE ? plusMillis(Long.MAX_VALUE).plusMillis(1) : plusMillis(-millisToSubtract));
878 }
879
880 /**
881 * Returns a copy of this duration with the specified duration in nanoseconds subtracted.
882 * <p>
883 * This instance is immutable and unaffected by this method call.
884 *
885 * @param nanosToSubtract the nanoseconds to subtract, positive or negative
886 * @return a {@code Duration} based on this duration with the specified nanoseconds subtracted, not null
887 * @throws ArithmeticException if numeric overflow occurs
888 */
889 public Duration minusNanos(long nanosToSubtract) {
890 return (nanosToSubtract == Long.MIN_VALUE ? plusNanos(Long.MAX_VALUE).plusNanos(1) : plusNanos(-nanosToSubtract));
891 }
892
893 //-----------------------------------------------------------------------
894 /**
895 * Returns a copy of this duration multiplied by the scalar.
896 * <p>
897 * This instance is immutable and unaffected by this method call.
898 *
899 * @param multiplicand the value to multiply the duration by, positive or negative
900 * @return a {@code Duration} based on this duration multiplied by the specified scalar, not null
901 * @throws ArithmeticException if numeric overflow occurs
902 */
903 public Duration multipliedBy(long multiplicand) {
904 if (multiplicand == 0) {
905 return ZERO;
906 }
907 if (multiplicand == 1) {
908 return this;
909 }
910 return create(toSeconds().multiply(BigDecimal.valueOf(multiplicand)));
911 }
912
913 /**
914 * Returns a copy of this duration divided by the specified value.
915 * <p>
916 * This instance is immutable and unaffected by this method call.
917 *
918 * @param divisor the value to divide the duration by, positive or negative, not zero
919 * @return a {@code Duration} based on this duration divided by the specified divisor, not null
920 * @throws ArithmeticException if the divisor is zero or if numeric overflow occurs
921 */
922 public Duration dividedBy(long divisor) {
923 if (divisor == 0) {
924 throw new ArithmeticException("Cannot divide by zero");
925 }
926 if (divisor == 1) {
927 return this;
928 }
929 return create(toSeconds().divide(BigDecimal.valueOf(divisor), RoundingMode.DOWN));
930 }
931
932 /**
933 * Converts this duration to the total length in seconds and
934 * fractional nanoseconds expressed as a {@code BigDecimal}.
935 *
936 * @return the total length of the duration in seconds, with a scale of 9, not null
937 */
938 private BigDecimal toSeconds() {
939 return BigDecimal.valueOf(seconds).add(BigDecimal.valueOf(nanos, 9));
940 }
941
942 /**
943 * Creates an instance of {@code Duration} from a number of seconds.
944 *
945 * @param seconds the number of seconds, up to scale 9, positive or negative
946 * @return a {@code Duration}, not null
947 * @throws ArithmeticException if numeric overflow occurs
948 */
949 private static Duration create(BigDecimal seconds) {
950 BigInteger nanos = seconds.movePointRight(9).toBigIntegerExact();
951 BigInteger[] divRem = nanos.divideAndRemainder(BI_NANOS_PER_SECOND);
952 if (divRem[0].bitLength() > 63) {
953 throw new ArithmeticException("Exceeds capacity of Duration: " + nanos);
954 }
955 return ofSeconds(divRem[0].longValue(), divRem[1].intValue());
956 }
957
958 //-----------------------------------------------------------------------
959 /**
960 * Returns a copy of this duration with the length negated.
961 * <p>
962 * This method swaps the sign of the total length of this duration.
963 * For example, {@code PT1.3S} will be returned as {@code PT-1.3S}.
964 * <p>
965 * This instance is immutable and unaffected by this method call.
966 *
967 * @return a {@code Duration} based on this duration with the amount negated, not null
968 * @throws ArithmeticException if numeric overflow occurs
969 */
970 public Duration negated() {
971 return multipliedBy(-1);
972 }
973
974 /**
975 * Returns a copy of this duration with a positive length.
976 * <p>
977 * This method returns a positive duration by effectively removing the sign from any negative total length.
978 * For example, {@code PT-1.3S} will be returned as {@code PT1.3S}.
979 * <p>
980 * This instance is immutable and unaffected by this method call.
981 *
982 * @return a {@code Duration} based on this duration with an absolute length, not null
983 * @throws ArithmeticException if numeric overflow occurs
984 */
985 public Duration abs() {
986 return isNegative() ? negated() : this;
987 }
988
989 //-------------------------------------------------------------------------
990 /**
991 * Adds this duration to the specified temporal object.
992 * <p>
993 * This returns a temporal object of the same observable type as the input
994 * with this duration added.
995 * <p>
996 * In most cases, it is clearer to reverse the calling pattern by using
997 * {@link Temporal#plus(TemporalAmount)}.
998 * <pre>
999 * // these two lines are equivalent, but the second approach is recommended
1000 * dateTime = thisDuration.addTo(dateTime);
1001 * dateTime = dateTime.plus(thisDuration);
1002 * </pre>
1003 * <p>
1004 * The calculation will add the seconds, then nanos.
1005 * Only non-zero amounts will be added.
1006 * <p>
1007 * This instance is immutable and unaffected by this method call.
1008 *
1009 * @param temporal the temporal object to adjust, not null
1010 * @return an object of the same type with the adjustment made, not null
1011 * @throws DateTimeException if unable to add
1012 * @throws ArithmeticException if numeric overflow occurs
1013 */
1014 @Override
1015 public Temporal addTo(Temporal temporal) {
1016 if (seconds != 0) {
1017 temporal = temporal.plus(seconds, SECONDS);
1018 }
1019 if (nanos != 0) {
1020 temporal = temporal.plus(nanos, NANOS);
1021 }
1022 return temporal;
1023 }
1024
1025 /**
1026 * Subtracts this duration from the specified temporal object.
1027 * <p>
1028 * This returns a temporal object of the same observable type as the input
1029 * with this duration subtracted.
1030 * <p>
1031 * In most cases, it is clearer to reverse the calling pattern by using
1032 * {@link Temporal#minus(TemporalAmount)}.
1033 * <pre>
1034 * // these two lines are equivalent, but the second approach is recommended
1035 * dateTime = thisDuration.subtractFrom(dateTime);
1036 * dateTime = dateTime.minus(thisDuration);
1037 * </pre>
1038 * <p>
1039 * The calculation will subtract the seconds, then nanos.
1040 * Only non-zero amounts will be added.
1041 * <p>
1042 * This instance is immutable and unaffected by this method call.
1043 *
1044 * @param temporal the temporal object to adjust, not null
1045 * @return an object of the same type with the adjustment made, not null
1046 * @throws DateTimeException if unable to subtract
1047 * @throws ArithmeticException if numeric overflow occurs
1048 */
1049 @Override
1050 public Temporal subtractFrom(Temporal temporal) {
1051 if (seconds != 0) {
1052 temporal = temporal.minus(seconds, SECONDS);
1053 }
1054 if (nanos != 0) {
1055 temporal = temporal.minus(nanos, NANOS);
1056 }
1057 return temporal;
1058 }
1059
1060 //-----------------------------------------------------------------------
1061 /**
1062 * Gets the number of minutes in this duration.
1063 * <p>
1064 * This returns the total number of minutes in the duration by dividing the
1065 * number of seconds by 86400.
1066 * This is based on the standard definition of a day as 24 hours.
1067 * <p>
1068 * This instance is immutable and unaffected by this method call.
1069 *
1070 * @return the number of minutes in the duration, may be negative
1071 */
1072 public long toDays() {
1073 return seconds / SECONDS_PER_DAY;
1074 }
1075
1076 /**
1077 * Gets the number of minutes in this duration.
1078 * <p>
1079 * This returns the total number of minutes in the duration by dividing the
1080 * number of seconds by 3600.
1081 * <p>
1082 * This instance is immutable and unaffected by this method call.
1083 *
1084 * @return the number of minutes in the duration, may be negative
1085 */
1086 public long toHours() {
1087 return seconds / SECONDS_PER_HOUR;
1088 }
1089
1090 /**
1091 * Gets the number of minutes in this duration.
1092 * <p>
1093 * This returns the total number of minutes in the duration by dividing the
1094 * number of seconds by 60.
1095 * <p>
1096 * This instance is immutable and unaffected by this method call.
1097 *
1098 * @return the number of minutes in the duration, may be negative
1099 */
1100 public long toMinutes() {
1101 return seconds / SECONDS_PER_MINUTE;
1102 }
1103
1104 /**
1105 * Converts this duration to the total length in milliseconds.
1106 * <p>
1107 * If this duration is too large to fit in a {@code long} milliseconds, then an
1108 * exception is thrown.
1109 * <p>
1110 * If this duration has greater than millisecond precision, then the conversion
1111 * will drop any excess precision information as though the amount in nanoseconds
1112 * was subject to integer division by one million.
1113 *
1114 * @return the total length of the duration in milliseconds
1115 * @throws ArithmeticException if numeric overflow occurs
1116 */
1117 public long toMillis() {
1118 long millis = Math.multiplyExact(seconds, 1000);
1119 millis = Math.addExact(millis, nanos / 1000_000);
1120 return millis;
1121 }
1122
1123 /**
1124 * Converts this duration to the total length in nanoseconds expressed as a {@code long}.
1125 * <p>
1126 * If this duration is too large to fit in a {@code long} nanoseconds, then an
1127 * exception is thrown.
1128 *
1129 * @return the total length of the duration in nanoseconds
1130 * @throws ArithmeticException if numeric overflow occurs
1131 */
1132 public long toNanos() {
1133 long millis = Math.multiplyExact(seconds, NANOS_PER_SECOND);
1134 millis = Math.addExact(millis, nanos);
1135 return millis;
1136 }
1137
1138 //-----------------------------------------------------------------------
1139 /**
1140 * Compares this duration to the specified {@code Duration}.
1141 * <p>
1142 * The comparison is based on the total length of the durations.
1143 * It is "consistent with equals", as defined by {@link Comparable}.
1144 *
1145 * @param otherDuration the other duration to compare to, not null
1146 * @return the comparator value, negative if less, positive if greater
1147 */
1148 @Override
1149 public int compareTo(Duration otherDuration) {
1150 int cmp = Long.compare(seconds, otherDuration.seconds);
1151 if (cmp != 0) {
1152 return cmp;
1153 }
1154 return nanos - otherDuration.nanos;
1155 }
1156
1157 //-----------------------------------------------------------------------
1158 /**
1159 * Checks if this duration is equal to the specified {@code Duration}.
1160 * <p>
1161 * The comparison is based on the total length of the durations.
1162 *
1163 * @param otherDuration the other duration, null returns false
1164 * @return true if the other duration is equal to this one
1165 */
1166 @Override
1167 public boolean equals(Object otherDuration) {
1168 if (this == otherDuration) {
1169 return true;
1170 }
1171 if (otherDuration instanceof Duration) {
1172 Duration other = (Duration) otherDuration;
1173 return this.seconds == other.seconds &&
1174 this.nanos == other.nanos;
1175 }
1176 return false;
1177 }
1178
1179 /**
1180 * A hash code for this duration.
1181 *
1182 * @return a suitable hash code
1183 */
1184 @Override
1185 public int hashCode() {
1186 return ((int) (seconds ^ (seconds >>> 32))) + (51 * nanos);
1187 }
1188
1189 //-----------------------------------------------------------------------
1190 /**
1191 * A string representation of this duration using ISO-8601 seconds
1192 * based representation, such as {@code PT8H6M12.345S}.
1193 * <p>
1194 * The format of the returned string will be {@code PTnHnMnS}, where n is
1195 * the relevant hours, minutes or seconds part of the duration.
1196 * Any fractional seconds are placed after a decimal point i the seconds section.
1197 * If a section has a zero value, it is omitted.
1198 * The hours, minutes and seconds will all have the same sign.
1199 * <p>
1200 * Examples:
1201 * <pre>
1202 * "20.345 seconds" -> "PT20.345S
1203 * "15 minutes" (15 * 60 seconds) -> "PT15M"
1204 * "10 hours" (10 * 3600 seconds) -> "PT10H"
1205 * "2 days" (2 * 86400 seconds) -> "PT48H"
1206 * </pre>
1207 * Note that multiples of 24 hours are not output as days to avoid confusion
1208 * with {@code Period}.
1209 *
1210 * @return an ISO-8601 representation of this duration, not null
1211 */
1212 @Override
1213 public String toString() {
1214 if (this == ZERO) {
1215 return "PT0S";
1216 }
1217 long hours = seconds / SECONDS_PER_HOUR;
1218 int minutes = (int) ((seconds % SECONDS_PER_HOUR) / SECONDS_PER_MINUTE);
1219 int secs = (int) (seconds % SECONDS_PER_MINUTE);
1220 StringBuilder buf = new StringBuilder(24);
1221 buf.append("PT");
1222 if (hours != 0) {
1223 buf.append(hours).append('H');
1224 }
1225 if (minutes != 0) {
1226 buf.append(minutes).append('M');
1227 }
1228 if (secs == 0 && nanos == 0 && buf.length() > 2) {
1229 return buf.toString();
1230 }
1231 if (secs < 0 && nanos > 0) {
1232 if (secs == -1) {
1233 buf.append("-0");
1234 } else {
1235 buf.append(secs + 1);
1236 }
1237 } else {
1238 buf.append(secs);
1239 }
1240 if (nanos > 0) {
1241 int pos = buf.length();
1242 if (secs < 0) {
1243 buf.append(2 * NANOS_PER_SECOND - nanos);
1244 } else {
1245 buf.append(nanos + NANOS_PER_SECOND);
1246 }
1247 while (buf.charAt(buf.length() - 1) == '0') {
1248 buf.setLength(buf.length() - 1);
1249 }
1250 buf.setCharAt(pos, '.');
1251 }
1252 buf.append('S');
1253 return buf.toString();
1254 }
1255
1256 //-----------------------------------------------------------------------
1257 /**
1258 * Writes the object using a
1259 * <a href="../../serialized-form.html#java.time.Ser">dedicated serialized form</a>.
1260 * <pre>
1261 * out.writeByte(1); // identifies this as a Duration
1262 * out.writeLong(seconds);
1263 * out.writeInt(nanos);
1264 * </pre>
1265 *
1266 * @return the instance of {@code Ser}, not null
1267 */
1268 private Object writeReplace() {
1269 return new Ser(Ser.DURATION_TYPE, this);
1270 }
1271
1272 /**
1273 * Defend against malicious streams.
1274 * @return never
1275 * @throws InvalidObjectException always
1276 */
1277 private Object readResolve() throws ObjectStreamException {
1278 throw new InvalidObjectException("Deserialization via serialization delegate");
1279 }
1280
1281 void writeExternal(DataOutput out) throws IOException {
1282 out.writeLong(seconds);
1283 out.writeInt(nanos);
1284 }
1285
1286 static Duration readExternal(DataInput in) throws IOException {
1287 long seconds = in.readLong();
1288 int nanos = in.readInt();
1289 return Duration.ofSeconds(seconds, nanos);
1290 }
1291
1292 }