1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  * Copyright (c) 1994, 2019, Oracle and/or its affiliates. All rights reserved.
4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5  *
6  * This code is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 only, as
8  * published by the Free Software Foundation.  Oracle designates this
9  * particular file as subject to the "Classpath" exception as provided
10  * by Oracle in the LICENSE file that accompanied this code.
11  *
12  * This code is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15  * version 2 for more details (a copy is included in the LICENSE file that
16  * accompanied this code).
17  *
18  * You should have received a copy of the GNU General Public License version
19  * 2 along with this work; if not, write to the Free Software Foundation,
20  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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25  */
26 
27 package java.util;
28 
29 import java.text.DateFormat;
30 import java.time.LocalDate;
31 import java.io.IOException;
32 import java.io.ObjectOutputStream;
33 import java.io.ObjectInputStream;
34 import java.lang.ref.SoftReference;
35 import java.time.Instant;
36 import sun.util.calendar.BaseCalendar;
37 import sun.util.calendar.CalendarDate;
38 import sun.util.calendar.CalendarSystem;
39 import sun.util.calendar.CalendarUtils;
40 import sun.util.calendar.Era;
41 import sun.util.calendar.Gregorian;
42 
43 /**
44  * The class {@code Date} represents a specific instant
45  * in time, with millisecond precision.
46  * <p>
47  * Prior to JDK&nbsp;1.1, the class {@code Date} had two additional
48  * functions.  It allowed the interpretation of dates as year, month, day, hour,
49  * minute, and second values.  It also allowed the formatting and parsing
50  * of date strings.  Unfortunately, the API for these functions was not
51  * amenable to internationalization.  As of JDK&nbsp;1.1, the
52  * {@code Calendar} class should be used to convert between dates and time
53  * fields and the {@code DateFormat} class should be used to format and
54  * parse date strings.
55  * The corresponding methods in {@code Date} are deprecated.
56  * <p>
57  * Although the {@code Date} class is intended to reflect
58  * coordinated universal time (UTC), it may not do so exactly,
59  * depending on the host environment of the Java Virtual Machine.
60  * Nearly all modern operating systems assume that 1&nbsp;day&nbsp;=
61  * 24&nbsp;&times;&nbsp;60&nbsp;&times;&nbsp;60&nbsp;= 86400 seconds
62  * in all cases. In UTC, however, about once every year or two there
63  * is an extra second, called a "leap second." The leap
64  * second is always added as the last second of the day, and always
65  * on December 31 or June 30. For example, the last minute of the
66  * year 1995 was 61 seconds long, thanks to an added leap second.
67  * Most computer clocks are not accurate enough to be able to reflect
68  * the leap-second distinction.
69  * <p>
70  * Some computer standards are defined in terms of Greenwich mean
71  * time (GMT), which is equivalent to universal time (UT).  GMT is
72  * the "civil" name for the standard; UT is the
73  * "scientific" name for the same standard. The
74  * distinction between UTC and UT is that UTC is based on an atomic
75  * clock and UT is based on astronomical observations, which for all
76  * practical purposes is an invisibly fine hair to split. Because the
77  * earth's rotation is not uniform (it slows down and speeds up
78  * in complicated ways), UT does not always flow uniformly. Leap
79  * seconds are introduced as needed into UTC so as to keep UTC within
80  * 0.9 seconds of UT1, which is a version of UT with certain
81  * corrections applied. There are other time and date systems as
82  * well; for example, the time scale used by the satellite-based
83  * global positioning system (GPS) is synchronized to UTC but is
84  * <i>not</i> adjusted for leap seconds. An interesting source of
85  * further information is the United States Naval Observatory (USNO):
86  * <blockquote><pre>
87  *     <a href="https://www.usno.navy.mil/USNO">https://www.usno.navy.mil/USNO</a>
88  * </pre></blockquote>
89  * <p>
90  * and the material regarding "Systems of Time" at:
91  * <blockquote><pre>
92  *     <a href="https://www.usno.navy.mil/USNO/time/master-clock/systems-of-time">https://www.usno.navy.mil/USNO/time/master-clock/systems-of-time</a>
93  * </pre></blockquote>
94  * <p>
95  * which has descriptions of various different time systems including
96  * UT, UT1, and UTC.
97  * <p>
98  * In all methods of class {@code Date} that accept or return
99  * year, month, date, hours, minutes, and seconds values, the
100  * following representations are used:
101  * <ul>
102  * <li>A year <i>y</i> is represented by the integer
103  *     <i>y</i>&nbsp;{@code - 1900}.
104  * <li>A month is represented by an integer from 0 to 11; 0 is January,
105  *     1 is February, and so forth; thus 11 is December.
106  * <li>A date (day of month) is represented by an integer from 1 to 31
107  *     in the usual manner.
108  * <li>An hour is represented by an integer from 0 to 23. Thus, the hour
109  *     from midnight to 1 a.m. is hour 0, and the hour from noon to 1
110  *     p.m. is hour 12.
111  * <li>A minute is represented by an integer from 0 to 59 in the usual manner.
112  * <li>A second is represented by an integer from 0 to 61; the values 60 and
113  *     61 occur only for leap seconds and even then only in Java
114  *     implementations that actually track leap seconds correctly. Because
115  *     of the manner in which leap seconds are currently introduced, it is
116  *     extremely unlikely that two leap seconds will occur in the same
117  *     minute, but this specification follows the date and time conventions
118  *     for ISO C.
119  * </ul>
120  * <p>
121  * In all cases, arguments given to methods for these purposes need
122  * not fall within the indicated ranges; for example, a date may be
123  * specified as January 32 and is interpreted as meaning February 1.
124  *
125  * @author  James Gosling
126  * @author  Arthur van Hoff
127  * @author  Alan Liu
128  * @see     java.text.DateFormat
129  * @see     java.util.Calendar
130  * @see     java.util.TimeZone
131  * @since   1.0
132  */
133 public class Date
134     implements java.io.Serializable, Cloneable, Comparable<Date>
135 {
136     private static final BaseCalendar gcal =
137                                 CalendarSystem.getGregorianCalendar();
138     private static BaseCalendar jcal;
139 
140     private transient long fastTime;
141 
142     /*
143      * If cdate is null, then fastTime indicates the time in millis.
144      * If cdate.isNormalized() is true, then fastTime and cdate are in
145      * synch. Otherwise, fastTime is ignored, and cdate indicates the
146      * time.
147      */
148     private transient BaseCalendar.Date cdate;
149 
150     // Initialized just before the value is used. See parse().
151     private static int defaultCenturyStart;
152 
153     /* use serialVersionUID from modified java.util.Date for
154      * interoperability with JDK1.1. The Date was modified to write
155      * and read only the UTC time.
156      */
157     @java.io.Serial
158     private static final long serialVersionUID = 7523967970034938905L;
159 
160     /**
161      * Allocates a {@code Date} object and initializes it so that
162      * it represents the time at which it was allocated, measured to the
163      * nearest millisecond.
164      *
165      * @see     java.lang.System#currentTimeMillis()
166      */
Date()167     public Date() {
168         this(System.currentTimeMillis());
169     }
170 
171     /**
172      * Allocates a {@code Date} object and initializes it to
173      * represent the specified number of milliseconds since the
174      * standard base time known as "the epoch", namely January 1,
175      * 1970, 00:00:00 GMT.
176      *
177      * @param   date   the milliseconds since January 1, 1970, 00:00:00 GMT.
178      * @see     java.lang.System#currentTimeMillis()
179      */
Date(long date)180     public Date(long date) {
181         fastTime = date;
182     }
183 
184     /**
185      * Allocates a {@code Date} object and initializes it so that
186      * it represents midnight, local time, at the beginning of the day
187      * specified by the {@code year}, {@code month}, and
188      * {@code date} arguments.
189      *
190      * @param   year    the year minus 1900.
191      * @param   month   the month between 0-11.
192      * @param   date    the day of the month between 1-31.
193      * @see     java.util.Calendar
194      * @deprecated As of JDK version 1.1,
195      * replaced by {@code Calendar.set(year + 1900, month, date)}
196      * or {@code GregorianCalendar(year + 1900, month, date)}.
197      */
198     @Deprecated
Date(int year, int month, int date)199     public Date(int year, int month, int date) {
200         this(year, month, date, 0, 0, 0);
201     }
202 
203     /**
204      * Allocates a {@code Date} object and initializes it so that
205      * it represents the instant at the start of the minute specified by
206      * the {@code year}, {@code month}, {@code date},
207      * {@code hrs}, and {@code min} arguments, in the local
208      * time zone.
209      *
210      * @param   year    the year minus 1900.
211      * @param   month   the month between 0-11.
212      * @param   date    the day of the month between 1-31.
213      * @param   hrs     the hours between 0-23.
214      * @param   min     the minutes between 0-59.
215      * @see     java.util.Calendar
216      * @deprecated As of JDK version 1.1,
217      * replaced by {@code Calendar.set(year + 1900, month, date, hrs, min)}
218      * or {@code GregorianCalendar(year + 1900, month, date, hrs, min)}.
219      */
220     @Deprecated
Date(int year, int month, int date, int hrs, int min)221     public Date(int year, int month, int date, int hrs, int min) {
222         this(year, month, date, hrs, min, 0);
223     }
224 
225     /**
226      * Allocates a {@code Date} object and initializes it so that
227      * it represents the instant at the start of the second specified
228      * by the {@code year}, {@code month}, {@code date},
229      * {@code hrs}, {@code min}, and {@code sec} arguments,
230      * in the local time zone.
231      *
232      * @param   year    the year minus 1900.
233      * @param   month   the month between 0-11.
234      * @param   date    the day of the month between 1-31.
235      * @param   hrs     the hours between 0-23.
236      * @param   min     the minutes between 0-59.
237      * @param   sec     the seconds between 0-59.
238      * @see     java.util.Calendar
239      * @deprecated As of JDK version 1.1,
240      * replaced by {@code Calendar.set(year + 1900, month, date, hrs, min, sec)}
241      * or {@code GregorianCalendar(year + 1900, month, date, hrs, min, sec)}.
242      */
243     @Deprecated
Date(int year, int month, int date, int hrs, int min, int sec)244     public Date(int year, int month, int date, int hrs, int min, int sec) {
245         int y = year + 1900;
246         // month is 0-based. So we have to normalize month to support Long.MAX_VALUE.
247         if (month >= 12) {
248             y += month / 12;
249             month %= 12;
250         } else if (month < 0) {
251             y += CalendarUtils.floorDivide(month, 12);
252             month = CalendarUtils.mod(month, 12);
253         }
254         BaseCalendar cal = getCalendarSystem(y);
255         cdate = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.getDefaultRef());
256         cdate.setNormalizedDate(y, month + 1, date).setTimeOfDay(hrs, min, sec, 0);
257         getTimeImpl();
258         cdate = null;
259     }
260 
261     /**
262      * Allocates a {@code Date} object and initializes it so that
263      * it represents the date and time indicated by the string
264      * {@code s}, which is interpreted as if by the
265      * {@link Date#parse} method.
266      *
267      * @param   s   a string representation of the date.
268      * @see     java.text.DateFormat
269      * @see     java.util.Date#parse(java.lang.String)
270      * @deprecated As of JDK version 1.1,
271      * replaced by {@code DateFormat.parse(String s)}.
272      */
273     @Deprecated
Date(String s)274     public Date(String s) {
275         this(parse(s));
276     }
277 
278     /**
279      * Return a copy of this object.
280      */
clone()281     public Object clone() {
282         Date d = null;
283         try {
284             d = (Date)super.clone();
285             if (cdate != null) {
286                 d.cdate = (BaseCalendar.Date) cdate.clone();
287             }
288         } catch (CloneNotSupportedException e) {} // Won't happen
289         return d;
290     }
291 
292     /**
293      * Determines the date and time based on the arguments. The
294      * arguments are interpreted as a year, month, day of the month,
295      * hour of the day, minute within the hour, and second within the
296      * minute, exactly as for the {@code Date} constructor with six
297      * arguments, except that the arguments are interpreted relative
298      * to UTC rather than to the local time zone. The time indicated is
299      * returned represented as the distance, measured in milliseconds,
300      * of that time from the epoch (00:00:00 GMT on January 1, 1970).
301      *
302      * @param   year    the year minus 1900.
303      * @param   month   the month between 0-11.
304      * @param   date    the day of the month between 1-31.
305      * @param   hrs     the hours between 0-23.
306      * @param   min     the minutes between 0-59.
307      * @param   sec     the seconds between 0-59.
308      * @return  the number of milliseconds since January 1, 1970, 00:00:00 GMT for
309      *          the date and time specified by the arguments.
310      * @see     java.util.Calendar
311      * @deprecated As of JDK version 1.1,
312      * replaced by {@code Calendar.set(year + 1900, month, date, hrs, min, sec)}
313      * or {@code GregorianCalendar(year + 1900, month, date, hrs, min, sec)}, using a UTC
314      * {@code TimeZone}, followed by {@code Calendar.getTime().getTime()}.
315      */
316     @Deprecated
UTC(int year, int month, int date, int hrs, int min, int sec)317     public static long UTC(int year, int month, int date,
318                            int hrs, int min, int sec) {
319         int y = year + 1900;
320         // month is 0-based. So we have to normalize month to support Long.MAX_VALUE.
321         if (month >= 12) {
322             y += month / 12;
323             month %= 12;
324         } else if (month < 0) {
325             y += CalendarUtils.floorDivide(month, 12);
326             month = CalendarUtils.mod(month, 12);
327         }
328         int m = month + 1;
329         BaseCalendar cal = getCalendarSystem(y);
330         BaseCalendar.Date udate = (BaseCalendar.Date) cal.newCalendarDate(null);
331         udate.setNormalizedDate(y, m, date).setTimeOfDay(hrs, min, sec, 0);
332 
333         // Use a Date instance to perform normalization. Its fastTime
334         // is the UTC value after the normalization.
335         Date d = new Date(0);
336         d.normalize(udate);
337         return d.fastTime;
338     }
339 
340     /**
341      * Attempts to interpret the string {@code s} as a representation
342      * of a date and time. If the attempt is successful, the time
343      * indicated is returned represented as the distance, measured in
344      * milliseconds, of that time from the epoch (00:00:00 GMT on
345      * January 1, 1970). If the attempt fails, an
346      * {@code IllegalArgumentException} is thrown.
347      * <p>
348      * It accepts many syntaxes; in particular, it recognizes the IETF
349      * standard date syntax: "Sat, 12 Aug 1995 13:30:00 GMT". It also
350      * understands the continental U.S. time-zone abbreviations, but for
351      * general use, a time-zone offset should be used: "Sat, 12 Aug 1995
352      * 13:30:00 GMT+0430" (4 hours, 30 minutes west of the Greenwich
353      * meridian). If no time zone is specified, the local time zone is
354      * assumed. GMT and UTC are considered equivalent.
355      * <p>
356      * The string {@code s} is processed from left to right, looking for
357      * data of interest. Any material in {@code s} that is within the
358      * ASCII parenthesis characters {@code (} and {@code )} is ignored.
359      * Parentheses may be nested. Otherwise, the only characters permitted
360      * within {@code s} are these ASCII characters:
361      * <blockquote><pre>
362      * abcdefghijklmnopqrstuvwxyz
363      * ABCDEFGHIJKLMNOPQRSTUVWXYZ
364      * 0123456789,+-:/</pre></blockquote>
365      * and whitespace characters.<p>
366      * A consecutive sequence of decimal digits is treated as a decimal
367      * number:<ul>
368      * <li>If a number is preceded by {@code +} or {@code -} and a year
369      *     has already been recognized, then the number is a time-zone
370      *     offset. If the number is less than 24, it is an offset measured
371      *     in hours. Otherwise, it is regarded as an offset in minutes,
372      *     expressed in 24-hour time format without punctuation. A
373      *     preceding {@code -} means a westward offset. Time zone offsets
374      *     are always relative to UTC (Greenwich). Thus, for example,
375      *     {@code -5} occurring in the string would mean "five hours west
376      *     of Greenwich" and {@code +0430} would mean "four hours and
377      *     thirty minutes east of Greenwich." It is permitted for the
378      *     string to specify {@code GMT}, {@code UT}, or {@code UTC}
379      *     redundantly-for example, {@code GMT-5} or {@code utc+0430}.
380      * <li>The number is regarded as a year number if one of the
381      *     following conditions is true:
382      * <ul>
383      *     <li>The number is equal to or greater than 70 and followed by a
384      *         space, comma, slash, or end of string
385      *     <li>The number is less than 70, and both a month and a day of
386      *         the month have already been recognized</li>
387      * </ul>
388      *     If the recognized year number is less than 100, it is
389      *     interpreted as an abbreviated year relative to a century of
390      *     which dates are within 80 years before and 19 years after
391      *     the time when the Date class is initialized.
392      *     After adjusting the year number, 1900 is subtracted from
393      *     it. For example, if the current year is 1999 then years in
394      *     the range 19 to 99 are assumed to mean 1919 to 1999, while
395      *     years from 0 to 18 are assumed to mean 2000 to 2018.  Note
396      *     that this is slightly different from the interpretation of
397      *     years less than 100 that is used in {@link java.text.SimpleDateFormat}.
398      * <li>If the number is followed by a colon, it is regarded as an hour,
399      *     unless an hour has already been recognized, in which case it is
400      *     regarded as a minute.
401      * <li>If the number is followed by a slash, it is regarded as a month
402      *     (it is decreased by 1 to produce a number in the range {@code 0}
403      *     to {@code 11}), unless a month has already been recognized, in
404      *     which case it is regarded as a day of the month.
405      * <li>If the number is followed by whitespace, a comma, a hyphen, or
406      *     end of string, then if an hour has been recognized but not a
407      *     minute, it is regarded as a minute; otherwise, if a minute has
408      *     been recognized but not a second, it is regarded as a second;
409      *     otherwise, it is regarded as a day of the month. </ul><p>
410      * A consecutive sequence of letters is regarded as a word and treated
411      * as follows:<ul>
412      * <li>A word that matches {@code AM}, ignoring case, is ignored (but
413      *     the parse fails if an hour has not been recognized or is less
414      *     than {@code 1} or greater than {@code 12}).
415      * <li>A word that matches {@code PM}, ignoring case, adds {@code 12}
416      *     to the hour (but the parse fails if an hour has not been
417      *     recognized or is less than {@code 1} or greater than {@code 12}).
418      * <li>Any word that matches any prefix of {@code SUNDAY, MONDAY, TUESDAY,
419      *     WEDNESDAY, THURSDAY, FRIDAY}, or {@code SATURDAY}, ignoring
420      *     case, is ignored. For example, {@code sat, Friday, TUE}, and
421      *     {@code Thurs} are ignored.
422      * <li>Otherwise, any word that matches any prefix of {@code JANUARY,
423      *     FEBRUARY, MARCH, APRIL, MAY, JUNE, JULY, AUGUST, SEPTEMBER,
424      *     OCTOBER, NOVEMBER}, or {@code DECEMBER}, ignoring case, and
425      *     considering them in the order given here, is recognized as
426      *     specifying a month and is converted to a number ({@code 0} to
427      *     {@code 11}). For example, {@code aug, Sept, april}, and
428      *     {@code NOV} are recognized as months. So is {@code Ma}, which
429      *     is recognized as {@code MARCH}, not {@code MAY}.
430      * <li>Any word that matches {@code GMT, UT}, or {@code UTC}, ignoring
431      *     case, is treated as referring to UTC.
432      * <li>Any word that matches {@code EST, CST, MST}, or {@code PST},
433      *     ignoring case, is recognized as referring to the time zone in
434      *     North America that is five, six, seven, or eight hours west of
435      *     Greenwich, respectively. Any word that matches {@code EDT, CDT,
436      *     MDT}, or {@code PDT}, ignoring case, is recognized as
437      *     referring to the same time zone, respectively, during daylight
438      *     saving time.</ul><p>
439      * Once the entire string s has been scanned, it is converted to a time
440      * result in one of two ways. If a time zone or time-zone offset has been
441      * recognized, then the year, month, day of month, hour, minute, and
442      * second are interpreted in UTC and then the time-zone offset is
443      * applied. Otherwise, the year, month, day of month, hour, minute, and
444      * second are interpreted in the local time zone.
445      *
446      * @param   s   a string to be parsed as a date.
447      * @return  the number of milliseconds since January 1, 1970, 00:00:00 GMT
448      *          represented by the string argument.
449      * @see     java.text.DateFormat
450      * @deprecated As of JDK version 1.1,
451      * replaced by {@code DateFormat.parse(String s)}.
452      */
453     @Deprecated
parse(String s)454     public static long parse(String s) {
455         int year = Integer.MIN_VALUE;
456         int mon = -1;
457         int mday = -1;
458         int hour = -1;
459         int min = -1;
460         int sec = -1;
461         int millis = -1;
462         int c = -1;
463         int i = 0;
464         int n = -1;
465         int wst = -1;
466         int tzoffset = -1;
467         int prevc = 0;
468     syntax:
469         {
470             if (s == null)
471                 break syntax;
472             int limit = s.length();
473             while (i < limit) {
474                 c = s.charAt(i);
475                 i++;
476                 if (c <= ' ' || c == ',')
477                     continue;
478                 if (c == '(') { // skip comments
479                     int depth = 1;
480                     while (i < limit) {
481                         c = s.charAt(i);
482                         i++;
483                         if (c == '(') depth++;
484                         else if (c == ')')
485                             if (--depth <= 0)
486                                 break;
487                     }
488                     continue;
489                 }
490                 if ('0' <= c && c <= '9') {
491                     n = c - '0';
492                     while (i < limit && '0' <= (c = s.charAt(i)) && c <= '9') {
493                         n = n * 10 + c - '0';
494                         i++;
495                     }
496                     if (prevc == '+' || prevc == '-' && year != Integer.MIN_VALUE) {
497                         // BEGIN Android-changed: Android specific time zone logic
498 
499                         if (tzoffset != 0 && tzoffset != -1)
500                             break syntax;
501 
502                         // timezone offset
503                         if (n < 24) {
504                             n = n * 60; // EG. "GMT-3"
505 
506                             // Support for Timezones of the form GMT-3:30. We look for an ':" and
507                             // parse the number following it as loosely as the original hours
508                             // section (i.e, no range or validity checks).
509                             int minutesPart = 0;
510                             if (i < limit && (s.charAt(i) == ':')) {
511                                 i++;
512                                 while (i < limit && '0' <= (c = s.charAt(i)) && c <= '9') {
513                                     minutesPart = (minutesPart * 10) + (c - '0');
514                                     i++;
515                                 }
516                             }
517 
518                             n += minutesPart;
519                         } else {
520                             n = (n % 100) + ((n / 100) * 60); // eg "GMT-0430"
521                         }
522 
523                         if (prevc == '+')   // plus means east of GMT
524                             n = -n;
525                         // END Android-changed: Android specific time zone logic
526 
527                         tzoffset = n;
528                     } else if (n >= 70)
529                         if (year != Integer.MIN_VALUE)
530                             break syntax;
531                         else if (c <= ' ' || c == ',' || c == '/' || i >= limit)
532                             // year = n < 1900 ? n : n - 1900;
533                             year = n;
534                         else
535                             break syntax;
536                     else if (c == ':')
537                         if (hour < 0)
538                             hour = (byte) n;
539                         else if (min < 0)
540                             min = (byte) n;
541                         else
542                             break syntax;
543                     else if (c == '/')
544                         if (mon < 0)
545                             mon = (byte) (n - 1);
546                         else if (mday < 0)
547                             mday = (byte) n;
548                         else
549                             break syntax;
550                     else if (i < limit && c != ',' && c > ' ' && c != '-')
551                         break syntax;
552                     else if (hour >= 0 && min < 0)
553                         min = (byte) n;
554                     else if (min >= 0 && sec < 0)
555                         sec = (byte) n;
556                     else if (mday < 0)
557                         mday = (byte) n;
558                     // Handle two-digit years < 70 (70-99 handled above).
559                     else if (year == Integer.MIN_VALUE && mon >= 0 && mday >= 0)
560                         year = n;
561                     else
562                         break syntax;
563                     prevc = 0;
564                 } else if (c == '/' || c == ':' || c == '+' || c == '-')
565                     prevc = c;
566                 else {
567                     int st = i - 1;
568                     while (i < limit) {
569                         c = s.charAt(i);
570                         if (!('A' <= c && c <= 'Z' || 'a' <= c && c <= 'z'))
571                             break;
572                         i++;
573                     }
574                     if (i <= st + 1)
575                         break syntax;
576                     int k;
577                     for (k = wtb.length; --k >= 0;)
578                         if (wtb[k].regionMatches(true, 0, s, st, i - st)) {
579                             int action = ttb[k];
580                             if (action != 0) {
581                                 if (action == 1) {  // pm
582                                     if (hour > 12 || hour < 1)
583                                         break syntax;
584                                     else if (hour < 12)
585                                         hour += 12;
586                                 } else if (action == 14) {  // am
587                                     if (hour > 12 || hour < 1)
588                                         break syntax;
589                                     else if (hour == 12)
590                                         hour = 0;
591                                 } else if (action <= 13) {  // month!
592                                     if (mon < 0)
593                                         mon = (byte) (action - 2);
594                                     else
595                                         break syntax;
596                                 } else {
597                                     tzoffset = action - 10000;
598                                 }
599                             }
600                             break;
601                         }
602                     if (k < 0)
603                         break syntax;
604                     prevc = 0;
605                 }
606             }
607             if (year == Integer.MIN_VALUE || mon < 0 || mday < 0)
608                 break syntax;
609             // Parse 2-digit years within the correct default century.
610             if (year < 100) {
611                 synchronized (Date.class) {
612                     if (defaultCenturyStart == 0) {
613                         defaultCenturyStart = gcal.getCalendarDate().getYear() - 80;
614                     }
615                 }
616                 year += (defaultCenturyStart / 100) * 100;
617                 if (year < defaultCenturyStart) year += 100;
618             }
619             if (sec < 0)
620                 sec = 0;
621             if (min < 0)
622                 min = 0;
623             if (hour < 0)
624                 hour = 0;
625             BaseCalendar cal = getCalendarSystem(year);
626             if (tzoffset == -1)  { // no time zone specified, have to use local
627                 BaseCalendar.Date ldate = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.getDefaultRef());
628                 ldate.setDate(year, mon + 1, mday);
629                 ldate.setTimeOfDay(hour, min, sec, 0);
630                 return cal.getTime(ldate);
631             }
632             BaseCalendar.Date udate = (BaseCalendar.Date) cal.newCalendarDate(null); // no time zone
633             udate.setDate(year, mon + 1, mday);
634             udate.setTimeOfDay(hour, min, sec, 0);
635             return cal.getTime(udate) + tzoffset * (60 * 1000);
636         }
637         // syntax error
638         throw new IllegalArgumentException();
639     }
640     private static final String wtb[] = {
641         "am", "pm",
642         "monday", "tuesday", "wednesday", "thursday", "friday",
643         "saturday", "sunday",
644         "january", "february", "march", "april", "may", "june",
645         "july", "august", "september", "october", "november", "december",
646         "gmt", "ut", "utc", "est", "edt", "cst", "cdt",
647         "mst", "mdt", "pst", "pdt"
648     };
649     private static final int ttb[] = {
650         14, 1, 0, 0, 0, 0, 0, 0, 0,
651         2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
652         10000 + 0, 10000 + 0, 10000 + 0,    // GMT/UT/UTC
653         10000 + 5 * 60, 10000 + 4 * 60,     // EST/EDT
654         10000 + 6 * 60, 10000 + 5 * 60,     // CST/CDT
655         10000 + 7 * 60, 10000 + 6 * 60,     // MST/MDT
656         10000 + 8 * 60, 10000 + 7 * 60      // PST/PDT
657     };
658 
659     /**
660      * Returns a value that is the result of subtracting 1900 from the
661      * year that contains or begins with the instant in time represented
662      * by this {@code Date} object, as interpreted in the local
663      * time zone.
664      *
665      * @return  the year represented by this date, minus 1900.
666      * @see     java.util.Calendar
667      * @deprecated As of JDK version 1.1,
668      * replaced by {@code Calendar.get(Calendar.YEAR) - 1900}.
669      */
670     @Deprecated
getYear()671     public int getYear() {
672         return normalize().getYear() - 1900;
673     }
674 
675     /**
676      * Sets the year of this {@code Date} object to be the specified
677      * value plus 1900. This {@code Date} object is modified so
678      * that it represents a point in time within the specified year,
679      * with the month, date, hour, minute, and second the same as
680      * before, as interpreted in the local time zone. (Of course, if
681      * the date was February 29, for example, and the year is set to a
682      * non-leap year, then the new date will be treated as if it were
683      * on March 1.)
684      *
685      * @param   year    the year value.
686      * @see     java.util.Calendar
687      * @deprecated As of JDK version 1.1,
688      * replaced by {@code Calendar.set(Calendar.YEAR, year + 1900)}.
689      */
690     @Deprecated
setYear(int year)691     public void setYear(int year) {
692         getCalendarDate().setNormalizedYear(year + 1900);
693     }
694 
695     /**
696      * Returns a number representing the month that contains or begins
697      * with the instant in time represented by this {@code Date} object.
698      * The value returned is between {@code 0} and {@code 11},
699      * with the value {@code 0} representing January.
700      *
701      * @return  the month represented by this date.
702      * @see     java.util.Calendar
703      * @deprecated As of JDK version 1.1,
704      * replaced by {@code Calendar.get(Calendar.MONTH)}.
705      */
706     @Deprecated
getMonth()707     public int getMonth() {
708         return normalize().getMonth() - 1; // adjust 1-based to 0-based
709     }
710 
711     /**
712      * Sets the month of this date to the specified value. This
713      * {@code Date} object is modified so that it represents a point
714      * in time within the specified month, with the year, date, hour,
715      * minute, and second the same as before, as interpreted in the
716      * local time zone. If the date was October 31, for example, and
717      * the month is set to June, then the new date will be treated as
718      * if it were on July 1, because June has only 30 days.
719      *
720      * @param   month   the month value between 0-11.
721      * @see     java.util.Calendar
722      * @deprecated As of JDK version 1.1,
723      * replaced by {@code Calendar.set(Calendar.MONTH, int month)}.
724      */
725     @Deprecated
setMonth(int month)726     public void setMonth(int month) {
727         int y = 0;
728         if (month >= 12) {
729             y = month / 12;
730             month %= 12;
731         } else if (month < 0) {
732             y = CalendarUtils.floorDivide(month, 12);
733             month = CalendarUtils.mod(month, 12);
734         }
735         BaseCalendar.Date d = getCalendarDate();
736         if (y != 0) {
737             d.setNormalizedYear(d.getNormalizedYear() + y);
738         }
739         d.setMonth(month + 1); // adjust 0-based to 1-based month numbering
740     }
741 
742     /**
743      * Returns the day of the month represented by this {@code Date} object.
744      * The value returned is between {@code 1} and {@code 31}
745      * representing the day of the month that contains or begins with the
746      * instant in time represented by this {@code Date} object, as
747      * interpreted in the local time zone.
748      *
749      * @return  the day of the month represented by this date.
750      * @see     java.util.Calendar
751      * @deprecated As of JDK version 1.1,
752      * replaced by {@code Calendar.get(Calendar.DAY_OF_MONTH)}.
753      */
754     @Deprecated
getDate()755     public int getDate() {
756         return normalize().getDayOfMonth();
757     }
758 
759     /**
760      * Sets the day of the month of this {@code Date} object to the
761      * specified value. This {@code Date} object is modified so that
762      * it represents a point in time within the specified day of the
763      * month, with the year, month, hour, minute, and second the same
764      * as before, as interpreted in the local time zone. If the date
765      * was April 30, for example, and the date is set to 31, then it
766      * will be treated as if it were on May 1, because April has only
767      * 30 days.
768      *
769      * @param   date   the day of the month value between 1-31.
770      * @see     java.util.Calendar
771      * @deprecated As of JDK version 1.1,
772      * replaced by {@code Calendar.set(Calendar.DAY_OF_MONTH, int date)}.
773      */
774     @Deprecated
setDate(int date)775     public void setDate(int date) {
776         getCalendarDate().setDayOfMonth(date);
777     }
778 
779     /**
780      * Returns the day of the week represented by this date. The
781      * returned value ({@code 0} = Sunday, {@code 1} = Monday,
782      * {@code 2} = Tuesday, {@code 3} = Wednesday, {@code 4} =
783      * Thursday, {@code 5} = Friday, {@code 6} = Saturday)
784      * represents the day of the week that contains or begins with
785      * the instant in time represented by this {@code Date} object,
786      * as interpreted in the local time zone.
787      *
788      * @return  the day of the week represented by this date.
789      * @see     java.util.Calendar
790      * @deprecated As of JDK version 1.1,
791      * replaced by {@code Calendar.get(Calendar.DAY_OF_WEEK)}.
792      */
793     @Deprecated
getDay()794     public int getDay() {
795         return normalize().getDayOfWeek() - BaseCalendar.SUNDAY;
796     }
797 
798     /**
799      * Returns the hour represented by this {@code Date} object. The
800      * returned value is a number ({@code 0} through {@code 23})
801      * representing the hour within the day that contains or begins
802      * with the instant in time represented by this {@code Date}
803      * object, as interpreted in the local time zone.
804      *
805      * @return  the hour represented by this date.
806      * @see     java.util.Calendar
807      * @deprecated As of JDK version 1.1,
808      * replaced by {@code Calendar.get(Calendar.HOUR_OF_DAY)}.
809      */
810     @Deprecated
getHours()811     public int getHours() {
812         return normalize().getHours();
813     }
814 
815     /**
816      * Sets the hour of this {@code Date} object to the specified value.
817      * This {@code Date} object is modified so that it represents a point
818      * in time within the specified hour of the day, with the year, month,
819      * date, minute, and second the same as before, as interpreted in the
820      * local time zone.
821      *
822      * @param   hours   the hour value.
823      * @see     java.util.Calendar
824      * @deprecated As of JDK version 1.1,
825      * replaced by {@code Calendar.set(Calendar.HOUR_OF_DAY, int hours)}.
826      */
827     @Deprecated
setHours(int hours)828     public void setHours(int hours) {
829         getCalendarDate().setHours(hours);
830     }
831 
832     /**
833      * Returns the number of minutes past the hour represented by this date,
834      * as interpreted in the local time zone.
835      * The value returned is between {@code 0} and {@code 59}.
836      *
837      * @return  the number of minutes past the hour represented by this date.
838      * @see     java.util.Calendar
839      * @deprecated As of JDK version 1.1,
840      * replaced by {@code Calendar.get(Calendar.MINUTE)}.
841      */
842     @Deprecated
getMinutes()843     public int getMinutes() {
844         return normalize().getMinutes();
845     }
846 
847     /**
848      * Sets the minutes of this {@code Date} object to the specified value.
849      * This {@code Date} object is modified so that it represents a point
850      * in time within the specified minute of the hour, with the year, month,
851      * date, hour, and second the same as before, as interpreted in the
852      * local time zone.
853      *
854      * @param   minutes   the value of the minutes.
855      * @see     java.util.Calendar
856      * @deprecated As of JDK version 1.1,
857      * replaced by {@code Calendar.set(Calendar.MINUTE, int minutes)}.
858      */
859     @Deprecated
setMinutes(int minutes)860     public void setMinutes(int minutes) {
861         getCalendarDate().setMinutes(minutes);
862     }
863 
864     /**
865      * Returns the number of seconds past the minute represented by this date.
866      * The value returned is between {@code 0} and {@code 61}. The
867      * values {@code 60} and {@code 61} can only occur on those
868      * Java Virtual Machines that take leap seconds into account.
869      *
870      * @return  the number of seconds past the minute represented by this date.
871      * @see     java.util.Calendar
872      * @deprecated As of JDK version 1.1,
873      * replaced by {@code Calendar.get(Calendar.SECOND)}.
874      */
875     @Deprecated
getSeconds()876     public int getSeconds() {
877         return normalize().getSeconds();
878     }
879 
880     /**
881      * Sets the seconds of this {@code Date} to the specified value.
882      * This {@code Date} object is modified so that it represents a
883      * point in time within the specified second of the minute, with
884      * the year, month, date, hour, and minute the same as before, as
885      * interpreted in the local time zone.
886      *
887      * @param   seconds   the seconds value.
888      * @see     java.util.Calendar
889      * @deprecated As of JDK version 1.1,
890      * replaced by {@code Calendar.set(Calendar.SECOND, int seconds)}.
891      */
892     @Deprecated
setSeconds(int seconds)893     public void setSeconds(int seconds) {
894         getCalendarDate().setSeconds(seconds);
895     }
896 
897     /**
898      * Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT
899      * represented by this {@code Date} object.
900      *
901      * @return  the number of milliseconds since January 1, 1970, 00:00:00 GMT
902      *          represented by this date.
903      */
getTime()904     public long getTime() {
905         return getTimeImpl();
906     }
907 
getTimeImpl()908     private final long getTimeImpl() {
909         if (cdate != null && !cdate.isNormalized()) {
910             normalize();
911         }
912         return fastTime;
913     }
914 
915     /**
916      * Sets this {@code Date} object to represent a point in time that is
917      * {@code time} milliseconds after January 1, 1970 00:00:00 GMT.
918      *
919      * @param   time   the number of milliseconds.
920      */
setTime(long time)921     public void setTime(long time) {
922         fastTime = time;
923         cdate = null;
924     }
925 
926     /**
927      * Tests if this date is before the specified date.
928      *
929      * @param   when   a date.
930      * @return  {@code true} if and only if the instant of time
931      *            represented by this {@code Date} object is strictly
932      *            earlier than the instant represented by {@code when};
933      *          {@code false} otherwise.
934      * @throws    NullPointerException if {@code when} is null.
935      */
before(Date when)936     public boolean before(Date when) {
937         return getMillisOf(this) < getMillisOf(when);
938     }
939 
940     /**
941      * Tests if this date is after the specified date.
942      *
943      * @param   when   a date.
944      * @return  {@code true} if and only if the instant represented
945      *          by this {@code Date} object is strictly later than the
946      *          instant represented by {@code when};
947      *          {@code false} otherwise.
948      * @throws    NullPointerException if {@code when} is null.
949      */
after(Date when)950     public boolean after(Date when) {
951         return getMillisOf(this) > getMillisOf(when);
952     }
953 
954     /**
955      * Compares two dates for equality.
956      * The result is {@code true} if and only if the argument is
957      * not {@code null} and is a {@code Date} object that
958      * represents the same point in time, to the millisecond, as this object.
959      * <p>
960      * Thus, two {@code Date} objects are equal if and only if the
961      * {@code getTime} method returns the same {@code long}
962      * value for both.
963      *
964      * @param   obj   the object to compare with.
965      * @return  {@code true} if the objects are the same;
966      *          {@code false} otherwise.
967      * @see     java.util.Date#getTime()
968      */
equals(Object obj)969     public boolean equals(Object obj) {
970         return obj instanceof Date && getTime() == ((Date) obj).getTime();
971     }
972 
973     /**
974      * Returns the millisecond value of this {@code Date} object
975      * without affecting its internal state.
976      */
getMillisOf(Date date)977     static final long getMillisOf(Date date) {
978         if (date.getClass() != Date.class) {
979             return date.getTime();
980         }
981         if (date.cdate == null || date.cdate.isNormalized()) {
982             return date.fastTime;
983         }
984         BaseCalendar.Date d = (BaseCalendar.Date) date.cdate.clone();
985         return gcal.getTime(d);
986     }
987 
988     /**
989      * Compares two Dates for ordering.
990      *
991      * @param   anotherDate   the {@code Date} to be compared.
992      * @return  the value {@code 0} if the argument Date is equal to
993      *          this Date; a value less than {@code 0} if this Date
994      *          is before the Date argument; and a value greater than
995      *      {@code 0} if this Date is after the Date argument.
996      * @since   1.2
997      * @throws    NullPointerException if {@code anotherDate} is null.
998      */
compareTo(Date anotherDate)999     public int compareTo(Date anotherDate) {
1000         long thisTime = getMillisOf(this);
1001         long anotherTime = getMillisOf(anotherDate);
1002         return (thisTime<anotherTime ? -1 : (thisTime==anotherTime ? 0 : 1));
1003     }
1004 
1005     /**
1006      * Returns a hash code value for this object. The result is the
1007      * exclusive OR of the two halves of the primitive {@code long}
1008      * value returned by the {@link Date#getTime}
1009      * method. That is, the hash code is the value of the expression:
1010      * <blockquote><pre>{@code
1011      * (int)(this.getTime()^(this.getTime() >>> 32))
1012      * }</pre></blockquote>
1013      *
1014      * @return  a hash code value for this object.
1015      */
hashCode()1016     public int hashCode() {
1017         long ht = this.getTime();
1018         return (int) ht ^ (int) (ht >> 32);
1019     }
1020 
1021     /**
1022      * Converts this {@code Date} object to a {@code String}
1023      * of the form:
1024      * <blockquote><pre>
1025      * dow mon dd hh:mm:ss zzz yyyy</pre></blockquote>
1026      * where:<ul>
1027      * <li>{@code dow} is the day of the week ({@code Sun, Mon, Tue, Wed,
1028      *     Thu, Fri, Sat}).
1029      * <li>{@code mon} is the month ({@code Jan, Feb, Mar, Apr, May, Jun,
1030      *     Jul, Aug, Sep, Oct, Nov, Dec}).
1031      * <li>{@code dd} is the day of the month ({@code 01} through
1032      *     {@code 31}), as two decimal digits.
1033      * <li>{@code hh} is the hour of the day ({@code 00} through
1034      *     {@code 23}), as two decimal digits.
1035      * <li>{@code mm} is the minute within the hour ({@code 00} through
1036      *     {@code 59}), as two decimal digits.
1037      * <li>{@code ss} is the second within the minute ({@code 00} through
1038      *     {@code 61}, as two decimal digits.
1039      * <li>{@code zzz} is the time zone (and may reflect daylight saving
1040      *     time). Standard time zone abbreviations include those
1041      *     recognized by the method {@code parse}. If time zone
1042      *     information is not available, then {@code zzz} is empty -
1043      *     that is, it consists of no characters at all.
1044      * <li>{@code yyyy} is the year, as four decimal digits.
1045      * </ul>
1046      *
1047      * @return  a string representation of this date.
1048      * @see     java.util.Date#toLocaleString()
1049      * @see     java.util.Date#toGMTString()
1050      */
toString()1051     public String toString() {
1052         // "EEE MMM dd HH:mm:ss zzz yyyy";
1053         BaseCalendar.Date date = normalize();
1054         StringBuilder sb = new StringBuilder(28);
1055         int index = date.getDayOfWeek();
1056         if (index == BaseCalendar.SUNDAY) {
1057             index = 8;
1058         }
1059         convertToAbbr(sb, wtb[index]).append(' ');                        // EEE
1060         convertToAbbr(sb, wtb[date.getMonth() - 1 + 2 + 7]).append(' ');  // MMM
1061         CalendarUtils.sprintf0d(sb, date.getDayOfMonth(), 2).append(' '); // dd
1062 
1063         CalendarUtils.sprintf0d(sb, date.getHours(), 2).append(':');   // HH
1064         CalendarUtils.sprintf0d(sb, date.getMinutes(), 2).append(':'); // mm
1065         CalendarUtils.sprintf0d(sb, date.getSeconds(), 2).append(' '); // ss
1066         TimeZone zi = date.getZone();
1067         if (zi != null) {
1068             sb.append(zi.getDisplayName(date.isDaylightTime(), TimeZone.SHORT, Locale.US)); // zzz
1069         } else {
1070             sb.append("GMT");
1071         }
1072         sb.append(' ').append(date.getYear());  // yyyy
1073         return sb.toString();
1074     }
1075 
1076     /**
1077      * Converts the given name to its 3-letter abbreviation (e.g.,
1078      * "monday" -> "Mon") and stored the abbreviation in the given
1079      * {@code StringBuilder}.
1080      */
convertToAbbr(StringBuilder sb, String name)1081     private static final StringBuilder convertToAbbr(StringBuilder sb, String name) {
1082         sb.append(Character.toUpperCase(name.charAt(0)));
1083         sb.append(name.charAt(1)).append(name.charAt(2));
1084         return sb;
1085     }
1086 
1087     /**
1088      * Creates a string representation of this {@code Date} object in an
1089      * implementation-dependent form. The intent is that the form should
1090      * be familiar to the user of the Java application, wherever it may
1091      * happen to be running. The intent is comparable to that of the
1092      * "{@code %c}" format supported by the {@code strftime()}
1093      * function of ISO&nbsp;C.
1094      *
1095      * @return  a string representation of this date, using the locale
1096      *          conventions.
1097      * @see     java.text.DateFormat
1098      * @see     java.util.Date#toString()
1099      * @see     java.util.Date#toGMTString()
1100      * @deprecated As of JDK version 1.1,
1101      * replaced by {@code DateFormat.format(Date date)}.
1102      */
1103     @Deprecated
toLocaleString()1104     public String toLocaleString() {
1105         DateFormat formatter = DateFormat.getDateTimeInstance();
1106         return formatter.format(this);
1107     }
1108 
1109     /**
1110      * Creates a string representation of this {@code Date} object of
1111      * the form:
1112      * <blockquote><pre>
1113      * d mon yyyy hh:mm:ss GMT</pre></blockquote>
1114      * where:<ul>
1115      * <li><i>d</i> is the day of the month ({@code 1} through {@code 31}),
1116      *     as one or two decimal digits.
1117      * <li><i>mon</i> is the month ({@code Jan, Feb, Mar, Apr, May, Jun, Jul,
1118      *     Aug, Sep, Oct, Nov, Dec}).
1119      * <li><i>yyyy</i> is the year, as four decimal digits.
1120      * <li><i>hh</i> is the hour of the day ({@code 00} through {@code 23}),
1121      *     as two decimal digits.
1122      * <li><i>mm</i> is the minute within the hour ({@code 00} through
1123      *     {@code 59}), as two decimal digits.
1124      * <li><i>ss</i> is the second within the minute ({@code 00} through
1125      *     {@code 61}), as two decimal digits.
1126      * <li><i>GMT</i> is exactly the ASCII letters "{@code GMT}" to indicate
1127      *     Greenwich Mean Time.
1128      * </ul><p>
1129      * The result does not depend on the local time zone.
1130      *
1131      * @return  a string representation of this date, using the Internet GMT
1132      *          conventions.
1133      * @see     java.text.DateFormat
1134      * @see     java.util.Date#toString()
1135      * @see     java.util.Date#toLocaleString()
1136      * @deprecated As of JDK version 1.1,
1137      * replaced by {@code DateFormat.format(Date date)}, using a
1138      * GMT {@code TimeZone}.
1139      */
1140     @Deprecated
toGMTString()1141     public String toGMTString() {
1142         // d MMM yyyy HH:mm:ss 'GMT'
1143         long t = getTime();
1144         BaseCalendar cal = getCalendarSystem(t);
1145         BaseCalendar.Date date =
1146             (BaseCalendar.Date) cal.getCalendarDate(getTime(), (TimeZone)null);
1147         StringBuilder sb = new StringBuilder(32);
1148         CalendarUtils.sprintf0d(sb, date.getDayOfMonth(), 1).append(' '); // d
1149         convertToAbbr(sb, wtb[date.getMonth() - 1 + 2 + 7]).append(' ');  // MMM
1150         sb.append(date.getYear()).append(' ');                            // yyyy
1151         CalendarUtils.sprintf0d(sb, date.getHours(), 2).append(':');      // HH
1152         CalendarUtils.sprintf0d(sb, date.getMinutes(), 2).append(':');    // mm
1153         CalendarUtils.sprintf0d(sb, date.getSeconds(), 2);                // ss
1154         sb.append(" GMT");                                                // ' GMT'
1155         return sb.toString();
1156     }
1157 
1158     /**
1159      * Returns the offset, measured in minutes, for the local time zone
1160      * relative to UTC that is appropriate for the time represented by
1161      * this {@code Date} object.
1162      * <p>
1163      * For example, in Massachusetts, five time zones west of Greenwich:
1164      * <blockquote><pre>
1165      * new Date(96, 1, 14).getTimezoneOffset() returns 300</pre></blockquote>
1166      * because on February 14, 1996, standard time (Eastern Standard Time)
1167      * is in use, which is offset five hours from UTC; but:
1168      * <blockquote><pre>
1169      * new Date(96, 5, 1).getTimezoneOffset() returns 240</pre></blockquote>
1170      * because on June 1, 1996, daylight saving time (Eastern Daylight Time)
1171      * is in use, which is offset only four hours from UTC.<p>
1172      * This method produces the same result as if it computed:
1173      * <blockquote><pre>
1174      * (this.getTime() - UTC(this.getYear(),
1175      *                       this.getMonth(),
1176      *                       this.getDate(),
1177      *                       this.getHours(),
1178      *                       this.getMinutes(),
1179      *                       this.getSeconds())) / (60 * 1000)
1180      * </pre></blockquote>
1181      *
1182      * @return  the time-zone offset, in minutes, for the current time zone.
1183      * @see     java.util.Calendar#ZONE_OFFSET
1184      * @see     java.util.Calendar#DST_OFFSET
1185      * @see     java.util.TimeZone#getDefault
1186      * @deprecated As of JDK version 1.1,
1187      * replaced by {@code -(Calendar.get(Calendar.ZONE_OFFSET) +
1188      * Calendar.get(Calendar.DST_OFFSET)) / (60 * 1000)}.
1189      */
1190     @Deprecated
getTimezoneOffset()1191     public int getTimezoneOffset() {
1192         int zoneOffset;
1193         if (cdate == null) {
1194             // Android-changed: Android specific time zone logic
1195             GregorianCalendar cal = new GregorianCalendar(fastTime);
1196             zoneOffset = (cal.get(Calendar.ZONE_OFFSET) + cal.get(Calendar.DST_OFFSET));
1197         } else {
1198             normalize();
1199             zoneOffset = cdate.getZoneOffset();
1200         }
1201         return -zoneOffset/60000;  // convert to minutes
1202     }
1203 
getCalendarDate()1204     private final BaseCalendar.Date getCalendarDate() {
1205         if (cdate == null) {
1206             BaseCalendar cal = getCalendarSystem(fastTime);
1207             cdate = (BaseCalendar.Date) cal.getCalendarDate(fastTime,
1208                                                             TimeZone.getDefaultRef());
1209         }
1210         return cdate;
1211     }
1212 
normalize()1213     private final BaseCalendar.Date normalize() {
1214         if (cdate == null) {
1215             BaseCalendar cal = getCalendarSystem(fastTime);
1216             cdate = (BaseCalendar.Date) cal.getCalendarDate(fastTime,
1217                                                             TimeZone.getDefaultRef());
1218             return cdate;
1219         }
1220 
1221         // Normalize cdate with the TimeZone in cdate first. This is
1222         // required for the compatible behavior.
1223         if (!cdate.isNormalized()) {
1224             cdate = normalize(cdate);
1225         }
1226 
1227         // If the default TimeZone has changed, then recalculate the
1228         // fields with the new TimeZone.
1229         TimeZone tz = TimeZone.getDefaultRef();
1230         if (tz != cdate.getZone()) {
1231             cdate.setZone(tz);
1232             CalendarSystem cal = getCalendarSystem(cdate);
1233             cal.getCalendarDate(fastTime, cdate);
1234         }
1235         return cdate;
1236     }
1237 
1238     // fastTime and the returned data are in sync upon return.
normalize(BaseCalendar.Date date)1239     private final BaseCalendar.Date normalize(BaseCalendar.Date date) {
1240         int y = date.getNormalizedYear();
1241         int m = date.getMonth();
1242         int d = date.getDayOfMonth();
1243         int hh = date.getHours();
1244         int mm = date.getMinutes();
1245         int ss = date.getSeconds();
1246         int ms = date.getMillis();
1247         TimeZone tz = date.getZone();
1248 
1249         // If the specified year can't be handled using a long value
1250         // in milliseconds, GregorianCalendar is used for full
1251         // compatibility with underflow and overflow. This is required
1252         // by some JCK tests. The limits are based max year values -
1253         // years that can be represented by max values of d, hh, mm,
1254         // ss and ms. Also, let GregorianCalendar handle the default
1255         // cutover year so that we don't need to worry about the
1256         // transition here.
1257         if (y == 1582 || y > 280000000 || y < -280000000) {
1258             if (tz == null) {
1259                 tz = TimeZone.getTimeZone("GMT");
1260             }
1261             GregorianCalendar gc = new GregorianCalendar(tz);
1262             gc.clear();
1263             gc.set(GregorianCalendar.MILLISECOND, ms);
1264             gc.set(y, m-1, d, hh, mm, ss);
1265             fastTime = gc.getTimeInMillis();
1266             BaseCalendar cal = getCalendarSystem(fastTime);
1267             date = (BaseCalendar.Date) cal.getCalendarDate(fastTime, tz);
1268             return date;
1269         }
1270 
1271         BaseCalendar cal = getCalendarSystem(y);
1272         if (cal != getCalendarSystem(date)) {
1273             date = (BaseCalendar.Date) cal.newCalendarDate(tz);
1274             date.setNormalizedDate(y, m, d).setTimeOfDay(hh, mm, ss, ms);
1275         }
1276         // Perform the GregorianCalendar-style normalization.
1277         fastTime = cal.getTime(date);
1278 
1279         // In case the normalized date requires the other calendar
1280         // system, we need to recalculate it using the other one.
1281         BaseCalendar ncal = getCalendarSystem(fastTime);
1282         if (ncal != cal) {
1283             date = (BaseCalendar.Date) ncal.newCalendarDate(tz);
1284             date.setNormalizedDate(y, m, d).setTimeOfDay(hh, mm, ss, ms);
1285             fastTime = ncal.getTime(date);
1286         }
1287         return date;
1288     }
1289 
1290     /**
1291      * Returns the Gregorian or Julian calendar system to use with the
1292      * given date. Use Gregorian from October 15, 1582.
1293      *
1294      * @param year normalized calendar year (not -1900)
1295      * @return the CalendarSystem to use for the specified date
1296      */
getCalendarSystem(int year)1297     private static final BaseCalendar getCalendarSystem(int year) {
1298         if (year >= 1582) {
1299             return gcal;
1300         }
1301         return getJulianCalendar();
1302     }
1303 
getCalendarSystem(long utc)1304     private static final BaseCalendar getCalendarSystem(long utc) {
1305         // Quickly check if the time stamp given by `utc' is the Epoch
1306         // or later. If it's before 1970, we convert the cutover to
1307         // local time to compare.
1308         if (utc >= 0
1309             || utc >= GregorianCalendar.DEFAULT_GREGORIAN_CUTOVER
1310                         - TimeZone.getDefaultRef().getOffset(utc)) {
1311             return gcal;
1312         }
1313         return getJulianCalendar();
1314     }
1315 
getCalendarSystem(BaseCalendar.Date cdate)1316     private static final BaseCalendar getCalendarSystem(BaseCalendar.Date cdate) {
1317         if (jcal == null) {
1318             return gcal;
1319         }
1320         if (cdate.getEra() != null) {
1321             return jcal;
1322         }
1323         return gcal;
1324     }
1325 
getJulianCalendar()1326     private static final synchronized BaseCalendar getJulianCalendar() {
1327         if (jcal == null) {
1328             jcal = (BaseCalendar) CalendarSystem.forName("julian");
1329         }
1330         return jcal;
1331     }
1332 
1333     /**
1334      * Save the state of this object to a stream (i.e., serialize it).
1335      *
1336      * @serialData The value returned by {@code getTime()}
1337      *             is emitted (long).  This represents the offset from
1338      *             January 1, 1970, 00:00:00 GMT in milliseconds.
1339      */
1340     @java.io.Serial
writeObject(ObjectOutputStream s)1341     private void writeObject(ObjectOutputStream s)
1342          throws IOException
1343     {
1344         s.defaultWriteObject();
1345         s.writeLong(getTimeImpl());
1346     }
1347 
1348     /**
1349      * Reconstitute this object from a stream (i.e., deserialize it).
1350      */
1351     @java.io.Serial
readObject(ObjectInputStream s)1352     private void readObject(ObjectInputStream s)
1353          throws IOException, ClassNotFoundException
1354     {
1355         s.defaultReadObject();
1356         fastTime = s.readLong();
1357     }
1358 
1359     /**
1360      * Obtains an instance of {@code Date} from an {@code Instant} object.
1361      * <p>
1362      * {@code Instant} uses a precision of nanoseconds, whereas {@code Date}
1363      * uses a precision of milliseconds.  The conversion will truncate any
1364      * excess precision information as though the amount in nanoseconds was
1365      * subject to integer division by one million.
1366      * <p>
1367      * {@code Instant} can store points on the time-line further in the future
1368      * and further in the past than {@code Date}. In this scenario, this method
1369      * will throw an exception.
1370      *
1371      * @param instant  the instant to convert
1372      * @return a {@code Date} representing the same point on the time-line as
1373      *  the provided instant
1374      * @throws    NullPointerException if {@code instant} is null.
1375      * @throws    IllegalArgumentException if the instant is too large to
1376      *  represent as a {@code Date}
1377      * @since 1.8
1378      */
from(Instant instant)1379     public static Date from(Instant instant) {
1380         try {
1381             return new Date(instant.toEpochMilli());
1382         } catch (ArithmeticException ex) {
1383             throw new IllegalArgumentException(ex);
1384         }
1385     }
1386 
1387     /**
1388      * Converts this {@code Date} object to an {@code Instant}.
1389      * <p>
1390      * The conversion creates an {@code Instant} that represents the same
1391      * point on the time-line as this {@code Date}.
1392      *
1393      * @return an instant representing the same point on the time-line as
1394      *  this {@code Date} object
1395      * @since 1.8
1396      */
toInstant()1397     public Instant toInstant() {
1398         return Instant.ofEpochMilli(getTime());
1399     }
1400 }
1401