Quelle Date.java

Sprache: JAVA

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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* accompanied this code).
*
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package java.util;

import java.text.DateFormat;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.time.Instant;
import sun.util.calendar.BaseCalendar;
import sun.util.calendar.CalendarSystem;
import sun.util.calendar.CalendarUtils;
import sun.util.calendar.ZoneInfo;

/**
* The class {@code Date} represents a specific instant
* in time, with millisecond precision.
* 
* Prior to JDK 1.1, the class {@code Date} had two additional
* functions. It allowed the interpretation of dates as year, month, day, hour,
* minute, and second values. It also allowed the formatting and parsing
* of date strings. Unfortunately, the API for these functions was not
* amenable to internationalization. As of JDK 1.1, the
* {@code Calendar} class should be used to convert between dates and time
* fields and the {@code DateFormat} class should be used to format and
* parse date strings.
* The corresponding methods in {@code Date} are deprecated.
* 
* Although the {@code Date} class is intended to reflect
* coordinated universal time (UTC), it may not do so exactly,
* depending on the host environment of the Java Virtual Machine.
* Nearly all modern operating systems assume that 1 day =
* 24 × 60 × 60&>nbsp;= 86400 seconds
* in all cases. In UTC, however, about once every year or two there
* is an extra second, called a "leap second." The leap
* second is always added as the last second of the day, and always
* on December 31 or June 30. For example, the last minute of the
* year 1995 was 61 seconds long, thanks to an added leap second.
* Most computer clocks are not accurate enough to be able to reflect
* the leap-second distinction.
* 
* Some computer standards are defined in terms of Greenwich mean
* time (GMT), which is equivalent to universal time (UT). GMT is
* the "civil" name for the standard; UT is the
* "scientific" name for the same standard. The
* distinction between UTC and UT is that UTC is based on an atomic
* clock and UT is based on astronomical observations, which for all
* practical purposes is an invisibly fine hair to split. Because the
* earth's rotation is not uniform (it slows down and speeds up
* in complicated ways), UT does not always flow uniformly. Leap
* seconds are introduced as needed into UTC so as to keep UTC within
* 0.9 seconds of UT1, which is a version of UT with certain
* corrections applied. There are other time and date systems as
* well; for example, the time scale used by the satellite-based
* global positioning system (GPS) is synchronized to UTC but is
* not adjusted for leap seconds. An interesting source of
* further information is the United States Naval Observatory (USNO):
* <blockquote><pre>
* <a href="https://www.usno.navy.mil/USNO">https://www.usno.navy.mil/USNO</a>
* </pre></blockquote>
* 
* and the material regarding "Systems of Time" at:
* <blockquote><pre>
* <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>
* </pre></blockquote>
* 
* which has descriptions of various different time systems including
* UT, UT1, and UTC.
* 
* In all methods of class {@code Date} that accept or return
* year, month, date, hours, minutes, and seconds values, the
* following representations are used:
* <ul>
* <li>A year y is represented by the integer
* y {@code - 1900}.
* <li>A month is represented by an integer from 0 to 11; 0 is January,
* 1 is February, and so forth; thus 11 is December.
* <li>A date (day of month) is represented by an integer from 1 to 31
* in the usual manner.
* <li>An hour is represented by an integer from 0 to 23. Thus, the hour
* from midnight to 1 a.m. is hour 0, and the hour from noon to 1
* p.m. is hour 12.
* <li>A minute is represented by an integer from 0 to 59 in the usual manner.
* <li>A second is represented by an integer from 0 to 61; the values 60 and
* 61 occur only for leap seconds and even then only in Java
* implementations that actually track leap seconds correctly. Because
* of the manner in which leap seconds are currently introduced, it is
* extremely unlikely that two leap seconds will occur in the same
* minute, but this specification follows the date and time conventions
* for ISO C.
* </ul>
* 
* In all cases, arguments given to methods for these purposes need
* not fall within the indicated ranges; for example, a date may be
* specified as January 32 and is interpreted as meaning February 1.
*
* @author James Gosling
* @author Arthur van Hoff
* @author Alan Liu
* @see java.text.DateFormat
* @see java.util.Calendar
* @see java.util.TimeZone
* @since 1.0
*/
public class Date
 implements java.io.Serializable, Cloneable, Comparable<Date>
{
 private static final BaseCalendar gcal =
 CalendarSystem.getGregorianCalendar();
 private static BaseCalendar jcal;

 private transient long fastTime;

 /*
 * If cdate is null, then fastTime indicates the time in millis.
 * If cdate.isNormalized() is true, then fastTime and cdate are in
 * synch. Otherwise, fastTime is ignored, and cdate indicates the
 * time.
 */
 private transient BaseCalendar.Date cdate;

 // Initialized just before the value is used. See parse().
 private static int defaultCenturyStart;

 /* use serialVersionUID from modified java.util.Date for
 * interoperability with JDK1.1. The Date was modified to write
 * and read only the UTC time.
 */
 @java.io.Serial
 private static final long serialVersionUID = 7523967970034938905L;

 /**
 * Allocates a {@code Date} object and initializes it so that
 * it represents the time at which it was allocated, measured to the
 * nearest millisecond.
 *
 * @see java.lang.System#currentTimeMillis()
 */
 public Date() {
 this(System.currentTimeMillis());
 }

 /**
 * Allocates a {@code Date} object and initializes it to
 * represent the specified number of milliseconds since the
 * standard base time known as "the epoch", namely January 1,
 * 1970, 00:00:00 GMT.
 *
 * @param date the milliseconds since January 1, 1970, 00:00:00 GMT.
 * @see java.lang.System#currentTimeMillis()
 */
 public Date(long date) {
 fastTime = date;
 }

 /**
 * Allocates a {@code Date} object and initializes it so that
 * it represents midnight, local time, at the beginning of the day
 * specified by the {@code year}, {@code month}, and
 * {@code date} arguments.
 *
 * @param year the year minus 1900.
 * @param month the month between 0-11.
 * @param date the day of the month between 1-31.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(year + 1900, month, date)}
 * or {@code GregorianCalendar(year + 1900, month, date)}.
 */
 @Deprecated
 public Date(int year, int month, int date) {
 this(year, month, date, 0, 0, 0);
 }

 /**
 * Allocates a {@code Date} object and initializes it so that
 * it represents the instant at the start of the minute specified by
 * the {@code year}, {@code month}, {@code date},
 * {@code hrs}, and {@code min} arguments, in the local
 * time zone.
 *
 * @param year the year minus 1900.
 * @param month the month between 0-11.
 * @param date the day of the month between 1-31.
 * @param hrs the hours between 0-23.
 * @param min the minutes between 0-59.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(year + 1900, month, date, hrs, min)}
 * or {@code GregorianCalendar(year + 1900, month, date, hrs, min)}.
 */
 @Deprecated
 public Date(int year, int month, int date, int hrs, int min) {
 this(year, month, date, hrs, min, 0);
 }

 /**
 * Allocates a {@code Date} object and initializes it so that
 * it represents the instant at the start of the second specified
 * by the {@code year}, {@code month}, {@code date},
 * {@code hrs}, {@code min}, and {@code sec} arguments,
 * in the local time zone.
 *
 * @param year the year minus 1900.
 * @param month the month between 0-11.
 * @param date the day of the month between 1-31.
 * @param hrs the hours between 0-23.
 * @param min the minutes between 0-59.
 * @param sec the seconds between 0-59.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(year + 1900, month, date, hrs, min, sec)}
 * or {@code GregorianCalendar(year + 1900, month, date, hrs, min, sec)}.
 */
 @Deprecated
 public Date(int year, int month, int date, int hrs, int min, int sec) {
 int y = year + 1900;
 // month is 0-based. So we have to normalize month to support Long.MAX_VALUE.
 if (month >= 12) {
 y += month / 12;
 month %= 12;
 } else if (month < 0) {
 y += CalendarUtils.floorDivide(month, 12);
 month = CalendarUtils.mod(month, 12);
 }
 BaseCalendar cal = getCalendarSystem(y);
 cdate = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.getDefaultRef());
 cdate.setNormalizedDate(y, month + 1, date).setTimeOfDay(hrs, min, sec, 0);
 getTimeImpl();
 cdate = null;
 }

 /**
 * Allocates a {@code Date} object and initializes it so that
 * it represents the date and time indicated by the string
 * {@code s}, which is interpreted as if by the
 * {@link Date#parse} method.
 *
 * @param s a string representation of the date.
 * @see java.text.DateFormat
 * @see java.util.Date#parse(java.lang.String)
 * @deprecated As of JDK version 1.1,
 * replaced by {@code DateFormat.parse(String s)}.
 */
 @Deprecated
 public Date(String s) {
 this(parse(s));
 }

 /**
 * Return a copy of this object.
 */
 public Object clone() {
 Date d = null;
 try {
 d = (Date)super.clone();
 if (cdate != null) {
 d.cdate = (BaseCalendar.Date) cdate.clone();
 }
 } catch (CloneNotSupportedException e) {} // Won't happen
 return d;
 }

 /**
 * Determines the date and time based on the arguments. The
 * arguments are interpreted as a year, month, day of the month,
 * hour of the day, minute within the hour, and second within the
 * minute, exactly as for the {@code Date} constructor with six
 * arguments, except that the arguments are interpreted relative
 * to UTC rather than to the local time zone. The time indicated is
 * returned represented as the distance, measured in milliseconds,
 * of that time from the epoch (00:00:00 GMT on January 1, 1970).
 *
 * @param year the year minus 1900.
 * @param month the month between 0-11.
 * @param date the day of the month between 1-31.
 * @param hrs the hours between 0-23.
 * @param min the minutes between 0-59.
 * @param sec the seconds between 0-59.
 * @return the number of milliseconds since January 1, 1970, 00:00:00 GMT for
 * the date and time specified by the arguments.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(year + 1900, month, date, hrs, min, sec)}
 * or {@code GregorianCalendar(year + 1900, month, date, hrs, min, sec)}, using a UTC
 * {@code TimeZone}, followed by {@code Calendar.getTime().getTime()}.
 */
 @Deprecated
 public static long UTC(int year, int month, int date,
 int hrs, int min, int sec) {
 int y = year + 1900;
 // month is 0-based. So we have to normalize month to support Long.MAX_VALUE.
 if (month >= 12) {
 y += month / 12;
 month %= 12;
 } else if (month < 0) {
 y += CalendarUtils.floorDivide(month, 12);
 month = CalendarUtils.mod(month, 12);
 }
 int m = month + 1;
 BaseCalendar cal = getCalendarSystem(y);
 BaseCalendar.Date udate = (BaseCalendar.Date) cal.newCalendarDate(null);
 udate.setNormalizedDate(y, m, date).setTimeOfDay(hrs, min, sec, 0);

 // Use a Date instance to perform normalization. Its fastTime
 // is the UTC value after the normalization.
 Date d = new Date(0);
 d.normalize(udate);
 return d.fastTime;
 }

 /**
 * Attempts to interpret the string {@code s} as a representation
 * of a date and time. If the attempt is successful, the time
 * indicated is returned represented as the distance, measured in
 * milliseconds, of that time from the epoch (00:00:00 GMT on
 * January 1, 1970). If the attempt fails, an
 * {@code IllegalArgumentException} is thrown.
 * 
 * It accepts many syntaxes; in particular, it recognizes the IETF
 * standard date syntax: "Sat, 12 Aug 1995 13:30:00 GMT". It also
 * understands the continental U.S. time-zone abbreviations, but for
 * general use, a time-zone offset should be used: "Sat, 12 Aug 1995
 * 13:30:00 GMT+0430" (4 hours, 30 minutes west of the Greenwich
 * meridian). If no time zone is specified, the local time zone is
 * assumed. GMT and UTC are considered equivalent.
 * 
 * The string {@code s} is processed from left to right, looking for
 * data of interest. Any material in {@code s} that is within the
 * ASCII parenthesis characters {@code (} and {@code )} is ignored.
 * Parentheses may be nested. Otherwise, the only characters permitted
 * within {@code s} are these ASCII characters:
 * <blockquote><pre>
 * abcdefghijklmnopqrstuvwxyz
 * ABCDEFGHIJKLMNOPQRSTUVWXYZ
 * 0123456789,+-:/</pre></blockquote>
 * and whitespace characters.
 * A consecutive sequence of decimal digits is treated as a decimal
 * number:<ul>
 * <li>If a number is preceded by {@code +} or {@code -} and a year
 * has already been recognized, then the number is a time-zone
 * offset. If the number is less than 24, it is an offset measured
 * in hours. Otherwise, it is regarded as an offset in minutes,
 * expressed in 24-hour time format without punctuation. A
 * preceding {@code -} means a westward offset. Time zone offsets
 * are always relative to UTC (Greenwich). Thus, for example,
 * {@code -5} occurring in the string would mean "five hours west
 * of Greenwich" and {@code +0430} would mean "four hours and
 * thirty minutes east of Greenwich." It is permitted for the
 * string to specify {@code GMT}, {@code UT}, or {@code UTC}
 * redundantly-for example, {@code GMT-5} or {@code utc+0430}.
 * <li>The number is regarded as a year number if one of the
 * following conditions is true:
 * <ul>
 * <li>The number is equal to or greater than 70 and followed by a
 * space, comma, slash, or end of string
 * <li>The number is less than 70, and both a month and a day of
 * the month have already been recognized</li>
 * </ul>
 * If the recognized year number is less than 100, it is
 * interpreted as an abbreviated year relative to a century of
 * which dates are within 80 years before and 19 years after
 * the time when the Date class is initialized.
 * After adjusting the year number, 1900 is subtracted from
 * it. For example, if the current year is 1999 then years in
 * the range 19 to 99 are assumed to mean 1919 to 1999, while
 * years from 0 to 18 are assumed to mean 2000 to 2018. Note
 * that this is slightly different from the interpretation of
 * years less than 100 that is used in {@link java.text.SimpleDateFormat}.
 * <li>If the number is followed by a colon, it is regarded as an hour,
 * unless an hour has already been recognized, in which case it is
 * regarded as a minute.
 * <li>If the number is followed by a slash, it is regarded as a month
 * (it is decreased by 1 to produce a number in the range {@code 0}
 * to {@code 11}), unless a month has already been recognized, in
 * which case it is regarded as a day of the month.
 * <li>If the number is followed by whitespace, a comma, a hyphen, or
 * end of string, then if an hour has been recognized but not a
 * minute, it is regarded as a minute; otherwise, if a minute has
 * been recognized but not a second, it is regarded as a second;
 * otherwise, it is regarded as a day of the month. </ul>
 * A consecutive sequence of letters is regarded as a word and treated
 * as follows:<ul>
 * <li>A word that matches {@code AM}, ignoring case, is ignored (but
 * the parse fails if an hour has not been recognized or is less
 * than {@code 1} or greater than {@code 12}).
 * <li>A word that matches {@code PM}, ignoring case, adds {@code 12}
 * to the hour (but the parse fails if an hour has not been
 * recognized or is less than {@code 1} or greater than {@code 12}).
 * <li>Any word that matches any prefix of {@code SUNDAY, MONDAY, TUESDAY,
 * WEDNESDAY, THURSDAY, FRIDAY}, or {@code SATURDAY}, ignoring
 * case, is ignored. For example, {@code sat, Friday, TUE}, and
 * {@code Thurs} are ignored.
 * <li>Otherwise, any word that matches any prefix of {@code JANUARY,
 * FEBRUARY, MARCH, APRIL, MAY, JUNE, JULY, AUGUST, SEPTEMBER,
 * OCTOBER, NOVEMBER}, or {@code DECEMBER}, ignoring case, and
 * considering them in the order given here, is recognized as
 * specifying a month and is converted to a number ({@code 0} to
 * {@code 11}). For example, {@code aug, Sept, april}, and
 * {@code NOV} are recognized as months. So is {@code Ma}, which
 * is recognized as {@code MARCH}, not {@code MAY}.
 * <li>Any word that matches {@code GMT, UT}, or {@code UTC}, ignoring
 * case, is treated as referring to UTC.
 * <li>Any word that matches {@code EST, CST, MST}, or {@code PST},
 * ignoring case, is recognized as referring to the time zone in
 * North America that is five, six, seven, or eight hours west of
 * Greenwich, respectively. Any word that matches {@code EDT, CDT,
 * MDT}, or {@code PDT}, ignoring case, is recognized as
 * referring to the same time zone, respectively, during daylight
 * saving time.</ul>
 * Once the entire string s has been scanned, it is converted to a time
 * result in one of two ways. If a time zone or time-zone offset has been
 * recognized, then the year, month, day of month, hour, minute, and
 * second are interpreted in UTC and then the time-zone offset is
 * applied. Otherwise, the year, month, day of month, hour, minute, and
 * second are interpreted in the local time zone.
 *
 * @param s a string to be parsed as a date.
 * @return the number of milliseconds since January 1, 1970, 00:00:00 GMT
 * represented by the string argument.
 * @see java.text.DateFormat
 * @deprecated As of JDK version 1.1,
 * replaced by {@code DateFormat.parse(String s)}.
 */
 @Deprecated
 public static long parse(String s) {
 int year = Integer.MIN_VALUE;
 int mon = -1;
 int mday = -1;
 int hour = -1;
 int min = -1;
 int sec = -1;
 int millis = -1;
 int c = -1;
 int i = 0;
 int n = -1;
 int wst = -1;
 int tzoffset = -1;
 int prevc = 0;
 syntax:
 {
 if (s == null)
 break syntax;
 int limit = s.length();
 while (i < limit) {
 c = s.charAt(i);
 i++;
 if (c <= ' ' || c == ',')
 continue;
 if (c == '(') { // skip comments
 int depth = 1;
 while (i < limit) {
 c = s.charAt(i);
 i++;
 if (c == '(') depth++;
 else if (c == ')')
 if (--depth <= 0)
 break;
 }
 continue;
 }
 if ('0' <= c && c <= '9') {
 n = c - '0';
 while (i < limit && '0' <= (c = s.charAt(i)) && c <= '9') {
 n = n * 10 + c - '0';
 i++;
 }
 if (prevc == '+' || prevc == '-' && year != Integer.MIN_VALUE) {
 // timezone offset
 if (n < 24)
 n = n * 60; // EG. "GMT-3"
 else
 n = n % 100 + n / 100 * 60; // eg "GMT-0430"
 if (prevc == '+') // plus means east of GMT
 n = -n;
 if (tzoffset != 0 && tzoffset != -1)
 break syntax;
 tzoffset = n;
 } else if (n >= 70)
 if (year != Integer.MIN_VALUE)
 break syntax;
 else if (c <= ' ' || c == ',' || c == '/' || i >= limit)
 // year = n < 1900 ? n : n - 1900;
 year = n;
 else
 break syntax;
 else if (c == ':')
 if (hour < 0)
 hour = (byte) n;
 else if (min < 0)
 min = (byte) n;
 else
 break syntax;
 else if (c == '/')
 if (mon < 0)
 mon = (byte) (n - 1);
 else if (mday < 0)
 mday = (byte) n;
 else
 break syntax;
 else if (i < limit && c != ',' && c > ' ' && c != '-')
 break syntax;
 else if (hour >= 0 && min < 0)
 min = (byte) n;
 else if (min >= 0 && sec < 0)
 sec = (byte) n;
 else if (mday < 0)
 mday = (byte) n;
 // Handle two-digit years < 70 (70-99 handled above).
 else if (year == Integer.MIN_VALUE && mon >= 0 && mday >= 0)
 year = n;
 else
 break syntax;
 prevc = 0;
 } else if (c == '/' || c == ':' || c == '+' || c == '-')
 prevc = c;
 else {
 int st = i - 1;
 while (i < limit) {
 c = s.charAt(i);
 if (!('A' <= c && c <= 'Z' || 'a' <= c && c <= 'z'))
 break;
 i++;
 }
 if (i <= st + 1)
 break syntax;
 int k;
 for (k = wtb.length; --k >= 0;)
 if (wtb[k].regionMatches(true, 0, s, st, i - st)) {
 int action = ttb[k];
 if (action != 0) {
 if (action == 1) { // pm
 if (hour > 12 || hour < 1)
 break syntax;
 else if (hour < 12)
 hour += 12;
 } else if (action == 14) { // am
 if (hour > 12 || hour < 1)
 break syntax;
 else if (hour == 12)
 hour = 0;
 } else if (action <= 13) { // month!
 if (mon < 0)
 mon = (byte) (action - 2);
 else
 break syntax;
 } else {
 tzoffset = action - 10000;
 }
 }
 break;
 }
 if (k < 0)
 break syntax;
 prevc = 0;
 }
 }
 if (year == Integer.MIN_VALUE || mon < 0 || mday < 0)
 break syntax;
 // Parse 2-digit years within the correct default century.
 if (year < 100) {
 synchronized (Date.class) {
 if (defaultCenturyStart == 0) {
 defaultCenturyStart = gcal.getCalendarDate().getYear() - 80;
 }
 }
 year += (defaultCenturyStart / 100) * 100;
 if (year < defaultCenturyStart) year += 100;
 }
 if (sec < 0)
 sec = 0;
 if (min < 0)
 min = 0;
 if (hour < 0)
 hour = 0;
 BaseCalendar cal = getCalendarSystem(year);
 if (tzoffset == -1) { // no time zone specified, have to use local
 BaseCalendar.Date ldate = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.getDefaultRef());
 ldate.setDate(year, mon + 1, mday);
 ldate.setTimeOfDay(hour, min, sec, 0);
 return cal.getTime(ldate);
 }
 BaseCalendar.Date udate = (BaseCalendar.Date) cal.newCalendarDate(null); // no time zone
 udate.setDate(year, mon + 1, mday);
 udate.setTimeOfDay(hour, min, sec, 0);
 return cal.getTime(udate) + tzoffset * (60 * 1000);
 }
 // syntax error
 throw new IllegalArgumentException();
 }
 private static final String wtb[] = {
 "am", "pm",
 "monday", "tuesday", "wednesday", "thursday", "friday",
 "saturday", "sunday",
 "january", "february", "march", "april", "may", "june",
 "july", "august", "september", "october", "november", "december",
 "gmt", "ut", "utc", "est", "edt", "cst", "cdt",
 "mst", "mdt", "pst", "pdt"
 };
 private static final int ttb[] = {
 14, 1, 0, 0, 0, 0, 0, 0, 0,
 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
 10000 + 0, 10000 + 0, 10000 + 0, // GMT/UT/UTC
 10000 + 5 * 60, 10000 + 4 * 60, // EST/EDT
 10000 + 6 * 60, 10000 + 5 * 60, // CST/CDT
 10000 + 7 * 60, 10000 + 6 * 60, // MST/MDT
 10000 + 8 * 60, 10000 + 7 * 60 // PST/PDT
 };

 /**
 * Returns a value that is the result of subtracting 1900 from the
 * year that contains or begins with the instant in time represented
 * by this {@code Date} object, as interpreted in the local
 * time zone.
 *
 * @return the year represented by this date, minus 1900.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.get(Calendar.YEAR) - 1900}.
 */
 @Deprecated
 public int getYear() {
 return normalize().getYear() - 1900;
 }

 /**
 * Sets the year of this {@code Date} object to be the specified
 * value plus 1900. This {@code Date} object is modified so
 * that it represents a point in time within the specified year,
 * with the month, date, hour, minute, and second the same as
 * before, as interpreted in the local time zone. (Of course, if
 * the date was February 29, for example, and the year is set to a
 * non-leap year, then the new date will be treated as if it were
 * on March 1.)
 *
 * @param year the year value.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(Calendar.YEAR, year + 1900)}.
 */
 @Deprecated
 public void setYear(int year) {
 getCalendarDate().setNormalizedYear(year + 1900);
 }

 /**
 * Returns a number representing the month that contains or begins
 * with the instant in time represented by this {@code Date} object.
 * The value returned is between {@code 0} and {@code 11},
 * with the value {@code 0} representing January.
 *
 * @return the month represented by this date.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.get(Calendar.MONTH)}.
 */
 @Deprecated
 public int getMonth() {
 return normalize().getMonth() - 1; // adjust 1-based to 0-based
 }

 /**
 * Sets the month of this date to the specified value. This
 * {@code Date} object is modified so that it represents a point
 * in time within the specified month, with the year, date, hour,
 * minute, and second the same as before, as interpreted in the
 * local time zone. If the date was October 31, for example, and
 * the month is set to June, then the new date will be treated as
 * if it were on July 1, because June has only 30 days.
 *
 * @param month the month value between 0-11.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(Calendar.MONTH, int month)}.
 */
 @Deprecated
 public void setMonth(int month) {
 int y = 0;
 if (month >= 12) {
 y = month / 12;
 month %= 12;
 } else if (month < 0) {
 y = CalendarUtils.floorDivide(month, 12);
 month = CalendarUtils.mod(month, 12);
 }
 BaseCalendar.Date d = getCalendarDate();
 if (y != 0) {
 d.setNormalizedYear(d.getNormalizedYear() + y);
 }
 d.setMonth(month + 1); // adjust 0-based to 1-based month numbering
 }

 /**
 * Returns the day of the month represented by this {@code Date} object.
 * The value returned is between {@code 1} and {@code 31}
 * representing the day of the month that contains or begins with the
 * instant in time represented by this {@code Date} object, as
 * interpreted in the local time zone.
 *
 * @return the day of the month represented by this date.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.get(Calendar.DAY_OF_MONTH)}.
 */
 @Deprecated
 public int getDate() {
 return normalize().getDayOfMonth();
 }

 /**
 * Sets the day of the month of this {@code Date} object to the
 * specified value. This {@code Date} object is modified so that
 * it represents a point in time within the specified day of the
 * month, with the year, month, hour, minute, and second the same
 * as before, as interpreted in the local time zone. If the date
 * was April 30, for example, and the date is set to 31, then it
 * will be treated as if it were on May 1, because April has only
 * 30 days.
 *
 * @param date the day of the month value between 1-31.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(Calendar.DAY_OF_MONTH, int date)}.
 */
 @Deprecated
 public void setDate(int date) {
 getCalendarDate().setDayOfMonth(date);
 }

 /**
 * Returns the day of the week represented by this date. The
 * returned value ({@code 0} = Sunday, {@code 1} = Monday,
 * {@code 2} = Tuesday, {@code 3} = Wednesday, {@code 4} =
 * Thursday, {@code 5} = Friday, {@code 6} = Saturday)
 * represents the day of the week that contains or begins with
 * the instant in time represented by this {@code Date} object,
 * as interpreted in the local time zone.
 *
 * @return the day of the week represented by this date.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.get(Calendar.DAY_OF_WEEK)}.
 */
 @Deprecated
 public int getDay() {
 return normalize().getDayOfWeek() - BaseCalendar.SUNDAY;
 }

 /**
 * Returns the hour represented by this {@code Date} object. The
 * returned value is a number ({@code 0} through {@code 23})
 * representing the hour within the day that contains or begins
 * with the instant in time represented by this {@code Date}
 * object, as interpreted in the local time zone.
 *
 * @return the hour represented by this date.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.get(Calendar.HOUR_OF_DAY)}.
 */
 @Deprecated
 public int getHours() {
 return normalize().getHours();
 }

 /**
 * Sets the hour of this {@code Date} object to the specified value.
 * This {@code Date} object is modified so that it represents a point
 * in time within the specified hour of the day, with the year, month,
 * date, minute, and second the same as before, as interpreted in the
 * local time zone.
 *
 * @param hours the hour value.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(Calendar.HOUR_OF_DAY, int hours)}.
 */
 @Deprecated
 public void setHours(int hours) {
 getCalendarDate().setHours(hours);
 }

 /**
 * Returns the number of minutes past the hour represented by this date,
 * as interpreted in the local time zone.
 * The value returned is between {@code 0} and {@code 59}.
 *
 * @return the number of minutes past the hour represented by this date.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.get(Calendar.MINUTE)}.
 */
 @Deprecated
 public int getMinutes() {
 return normalize().getMinutes();
 }

 /**
 * Sets the minutes of this {@code Date} object to the specified value.
 * This {@code Date} object is modified so that it represents a point
 * in time within the specified minute of the hour, with the year, month,
 * date, hour, and second the same as before, as interpreted in the
 * local time zone.
 *
 * @param minutes the value of the minutes.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(Calendar.MINUTE, int minutes)}.
 */
 @Deprecated
 public void setMinutes(int minutes) {
 getCalendarDate().setMinutes(minutes);
 }

 /**
 * Returns the number of seconds past the minute represented by this date.
 * The value returned is between {@code 0} and {@code 61}. The
 * values {@code 60} and {@code 61} can only occur on those
 * Java Virtual Machines that take leap seconds into account.
 *
 * @return the number of seconds past the minute represented by this date.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.get(Calendar.SECOND)}.
 */
 @Deprecated
 public int getSeconds() {
 return normalize().getSeconds();
 }

 /**
 * Sets the seconds of this {@code Date} to the specified value.
 * This {@code Date} object is modified so that it represents a
 * point in time within the specified second of the minute, with
 * the year, month, date, hour, and minute the same as before, as
 * interpreted in the local time zone.
 *
 * @param seconds the seconds value.
 * @see java.util.Calendar
 * @deprecated As of JDK version 1.1,
 * replaced by {@code Calendar.set(Calendar.SECOND, int seconds)}.
 */
 @Deprecated
 public void setSeconds(int seconds) {
 getCalendarDate().setSeconds(seconds);
 }

 /**
 * Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT
 * represented by this {@code Date} object.
 *
 * @return the number of milliseconds since January 1, 1970, 00:00:00 GMT
 * represented by this date.
 */
 public long getTime() {
 return getTimeImpl();
 }

 private final long getTimeImpl() {
 if (cdate != null && !cdate.isNormalized()) {
 normalize();
 }
 return fastTime;
 }

 /**
 * Sets this {@code Date} object to represent a point in time that is
 * {@code time} milliseconds after January 1, 1970 00:00:00 GMT.
 *
 * @param time the number of milliseconds.
 */
 public void setTime(long time) {
 fastTime = time;
 cdate = null;
 }

 /**
 * Tests if this date is before the specified date.
 *
 * @param when a date.
 * @return {@code true} if and only if the instant of time
 * represented by this {@code Date} object is strictly
 * earlier than the instant represented by {@code when};
 * {@code false} otherwise.
 * @throws NullPointerException if {@code when} is null.
 */
 public boolean before(Date when) {
 return getMillisOf(this) < getMillisOf(when);
 }

 /**
 * Tests if this date is after the specified date.
 *
 * @param when a date.
 * @return {@code true} if and only if the instant represented
 * by this {@code Date} object is strictly later than the
 * instant represented by {@code when};
 * {@code false} otherwise.
 * @throws NullPointerException if {@code when} is null.
 */
 public boolean after(Date when) {
 return getMillisOf(this) > getMillisOf(when);
 }

 /**
 * Compares two dates for equality.
 * The result is {@code true} if and only if the argument is
 * not {@code null} and is a {@code Date} object that
 * represents the same point in time, to the millisecond, as this object.
 * 
 * Thus, two {@code Date} objects are equal if and only if the
 * {@code getTime} method returns the same {@code long}
 * value for both.
 *
 * @param obj the object to compare with.
 * @return {@code true} if the objects are the same;
 * {@code false} otherwise.
 * @see java.util.Date#getTime()
 */
 public boolean equals(Object obj) {
 return obj instanceof Date && getTime() == ((Date) obj).getTime();
 }

 /**
 * Returns the millisecond value of this {@code Date} object
 * without affecting its internal state.
 */
 static final long getMillisOf(Date date) {
 if (date.getClass() != Date.class) {
 return date.getTime();
 }
 if (date.cdate == null || date.cdate.isNormalized()) {
 return date.fastTime;
 }
 BaseCalendar.Date d = (BaseCalendar.Date) date.cdate.clone();
 return gcal.getTime(d);
 }

 /**
 * Compares two Dates for ordering.
 *
 * @param anotherDate the {@code Date} to be compared.
 * @return the value {@code 0} if the argument Date is equal to
 * this Date; a value less than {@code 0} if this Date
 * is before the Date argument; and a value greater than
 * {@code 0} if this Date is after the Date argument.
 * @since 1.2
 * @throws NullPointerException if {@code anotherDate} is null.
 */
 @Override
 public int compareTo(Date anotherDate) {
 return Long.compare(getMillisOf(this), getMillisOf(anotherDate));
 }

 /**
 * Returns a hash code value for this object. The result is the
 * exclusive OR of the two halves of the primitive {@code long}
 * value returned by the {@link Date#getTime}
 * method. That is, the hash code is the value of the expression:
 * <blockquote><pre>{@code
 * (int)(this.getTime()^(this.getTime() >>> 32))
 * }</pre></blockquote>
 *
 * @return a hash code value for this object.
 */
 public int hashCode() {
 long ht = this.getTime();
 return (int) ht ^ (int) (ht >> 32);
 }

 /**
 * Converts this {@code Date} object to a {@code String}
 * of the form:
 * <blockquote><pre>
 * dow mon dd hh:mm:ss zzz yyyy</pre></blockquote>
 * where:<ul>
 * <li>{@code dow} is the day of the week ({@code Sun, Mon, Tue, Wed,
 * Thu, Fri, Sat}).
 * <li>{@code mon} is the month ({@code Jan, Feb, Mar, Apr, May, Jun,
 * Jul, Aug, Sep, Oct, Nov, Dec}).
 * <li>{@code dd} is the day of the month ({@code 01} through
 * {@code 31}), as two decimal digits.
 * <li>{@code hh} is the hour of the day ({@code 00} through
 * {@code 23}), as two decimal digits.
 * <li>{@code mm} is the minute within the hour ({@code 00} through
 * {@code 59}), as two decimal digits.
 * <li>{@code ss} is the second within the minute ({@code 00} through
 * {@code 61}, as two decimal digits.
 * <li>{@code zzz} is the time zone (and may reflect daylight saving
 * time). Standard time zone abbreviations include those
 * recognized by the method {@code parse}. If time zone
 * information is not available, then {@code zzz} is empty -
 * that is, it consists of no characters at all.
 * <li>{@code yyyy} is the year, as four decimal digits.
 * </ul>
 *
 * @return a string representation of this date.
 * @see java.util.Date#toLocaleString()
 * @see java.util.Date#toGMTString()
 */
 public String toString() {
 // "EEE MMM dd HH:mm:ss zzz yyyy";
 BaseCalendar.Date date = normalize();
 StringBuilder sb = new StringBuilder(28);
 int index = date.getDayOfWeek();
 if (index == BaseCalendar.SUNDAY) {
 index = 8;
 }
 convertToAbbr(sb, wtb[index]).append(' '); // EEE
 convertToAbbr(sb, wtb[date.getMonth() - 1 + 2 + 7]).append(' '); // MMM
 CalendarUtils.sprintf0d(sb, date.getDayOfMonth(), 2).append(' '); // dd

 CalendarUtils.sprintf0d(sb, date.getHours(), 2).append(':'); // HH
 CalendarUtils.sprintf0d(sb, date.getMinutes(), 2).append(':'); // mm
 CalendarUtils.sprintf0d(sb, date.getSeconds(), 2).append(' '); // ss
 TimeZone zi = date.getZone();
 if (zi != null) {
 sb.append(zi.getDisplayName(date.isDaylightTime(), TimeZone.SHORT, Locale.US)); // zzz
 } else {
 sb.append("GMT");
 }
 sb.append(' ').append(date.getYear()); // yyyy
 return sb.toString();
 }

 /**
 * Converts the given name to its 3-letter abbreviation (e.g.,
 * "monday" -> "Mon") and stored the abbreviation in the given
 * {@code StringBuilder}.
 */
 private static final StringBuilder convertToAbbr(StringBuilder sb, String name) {
 sb.append(Character.toUpperCase(name.charAt(0)));
 sb.append(name.charAt(1)).append(name.charAt(2));
 return sb;
 }

 /**
 * Creates a string representation of this {@code Date} object in an
 * implementation-dependent form. The intent is that the form should
 * be familiar to the user of the Java application, wherever it may
 * happen to be running. The intent is comparable to that of the
 * "{@code %c}" format supported by the {@code strftime()}
 * function of ISO C.
 *
 * @return a string representation of this date, using the locale
 * conventions.
 * @see java.text.DateFormat
 * @see java.util.Date#toString()
 * @see java.util.Date#toGMTString()
 * @deprecated As of JDK version 1.1,
 * replaced by {@code DateFormat.format(Date date)}.
 */
 @Deprecated
 public String toLocaleString() {
 DateFormat formatter = DateFormat.getDateTimeInstance();
 return formatter.format(this);
 }

 /**
 * Creates a string representation of this {@code Date} object of
 * the form:
 * <blockquote><pre>
 * d mon yyyy hh:mm:ss GMT</pre></blockquote>
 * where:<ul>
 * <li>d is the day of the month ({@code 1} through {@code 31}),
 * as one or two decimal digits.
 * <li>mon is the month ({@code Jan, Feb, Mar, Apr, May, Jun, Jul,
 * Aug, Sep, Oct, Nov, Dec}).
 * <li>yyyy is the year, as four decimal digits.
 * <li>hh is the hour of the day ({@code 00} through {@code 23}),
 * as two decimal digits.
 * <li>mm is the minute within the hour ({@code 00} through
 * {@code 59}), as two decimal digits.
 * <li>ss is the second within the minute ({@code 00} through
 * {@code 61}), as two decimal digits.
 * <li>GMT is exactly the ASCII letters "{@code GMT}" to indicate
 * Greenwich Mean Time.
 * </ul>
 * The result does not depend on the local time zone.
 *
 * @return a string representation of this date, using the Internet GMT
 * conventions.
 * @see java.text.DateFormat
 * @see java.util.Date#toString()
 * @see java.util.Date#toLocaleString()
 * @deprecated As of JDK version 1.1,
 * replaced by {@code DateFormat.format(Date date)}, using a
 * GMT {@code TimeZone}.
 */
 @Deprecated
 public String toGMTString() {
 // d MMM yyyy HH:mm:ss 'GMT'
 long t = getTime();
 BaseCalendar cal = getCalendarSystem(t);
 BaseCalendar.Date date =
 (BaseCalendar.Date) cal.getCalendarDate(getTime(), (TimeZone)null);
 StringBuilder sb = new StringBuilder(32);
 CalendarUtils.sprintf0d(sb, date.getDayOfMonth(), 1).append(' '); // d
 convertToAbbr(sb, wtb[date.getMonth() - 1 + 2 + 7]).append(' '); // MMM
 sb.append(date.getYear()).append(' '); // yyyy
 CalendarUtils.sprintf0d(sb, date.getHours(), 2).append(':'); // HH
 CalendarUtils.sprintf0d(sb, date.getMinutes(), 2).append(':'); // mm
 CalendarUtils.sprintf0d(sb, date.getSeconds(), 2); // ss
 sb.append(" GMT"); // ' GMT'
 return sb.toString();
 }

 /**
 * Returns the offset, measured in minutes, for the local time zone
 * relative to UTC that is appropriate for the time represented by
 * this {@code Date} object.
 * 
 * For example, in Massachusetts, five time zones west of Greenwich:
 * <blockquote><pre>
 * new Date(96, 1, 14).getTimezoneOffset() returns 300</pre></blockquote>
 * because on February 14, 1996, standard time (Eastern Standard Time)
 * is in use, which is offset five hours from UTC; but:
 * <blockquote><pre>
 * new Date(96, 5, 1).getTimezoneOffset() returns 240</pre></blockquote>
 * because on June 1, 1996, daylight saving time (Eastern Daylight Time)
 * is in use, which is offset only four hours from UTC.
 * This method produces the same result as if it computed:
 * <blockquote><pre>
 * (this.getTime() - UTC(this.getYear(),
 * this.getMonth(),
 * this.getDate(),
 * this.getHours(),
 * this.getMinutes(),
 * this.getSeconds())) / (60 * 1000)
 * </pre></blockquote>
 *
 * @return the time-zone offset, in minutes, for the current time zone.
 * @see java.util.Calendar#ZONE_OFFSET
 * @see java.util.Calendar#DST_OFFSET
 * @see java.util.TimeZone#getDefault
 * @deprecated As of JDK version 1.1,
 * replaced by {@code -(Calendar.get(Calendar.ZONE_OFFSET) +
 * Calendar.get(Calendar.DST_OFFSET)) / (60 * 1000)}.
 */
 @Deprecated
 public int getTimezoneOffset() {
 int zoneOffset;
 if (cdate == null) {
 TimeZone tz = TimeZone.getDefaultRef();
 if (tz instanceof ZoneInfo) {
 zoneOffset = ((ZoneInfo)tz).getOffsets(fastTime, null);
 } else {
 zoneOffset = tz.getOffset(fastTime);
 }
 } else {
 normalize();
 zoneOffset = cdate.getZoneOffset();
 }
 return -zoneOffset/60000; // convert to minutes
 }

 private final BaseCalendar.Date getCalendarDate() {
 if (cdate == null) {
 BaseCalendar cal = getCalendarSystem(fastTime);
 cdate = (BaseCalendar.Date) cal.getCalendarDate(fastTime,
 TimeZone.getDefaultRef());
 }
 return cdate;
 }

 private final BaseCalendar.Date normalize() {
 if (cdate == null) {
 BaseCalendar cal = getCalendarSystem(fastTime);
 cdate = (BaseCalendar.Date) cal.getCalendarDate(fastTime,
 TimeZone.getDefaultRef());
 return cdate;
 }

 // Normalize cdate with the TimeZone in cdate first. This is
 // required for the compatible behavior.
 if (!cdate.isNormalized()) {
 cdate = normalize(cdate);
 }

 // If the default TimeZone has changed, then recalculate the
 // fields with the new TimeZone.
 TimeZone tz = TimeZone.getDefaultRef();
 if (tz != cdate.getZone()) {
 cdate.setZone(tz);
 CalendarSystem cal = getCalendarSystem(cdate);
 cal.getCalendarDate(fastTime, cdate);
 }
 return cdate;
 }

 // fastTime and the returned data are in sync upon return.
 private final BaseCalendar.Date normalize(BaseCalendar.Date date) {
 int y = date.getNormalizedYear();
 int m = date.getMonth();
 int d = date.getDayOfMonth();
 int hh = date.getHours();
 int mm = date.getMinutes();
 int ss = date.getSeconds();
 int ms = date.getMillis();
 TimeZone tz = date.getZone();

 // If the specified year can't be handled using a long value
 // in milliseconds, GregorianCalendar is used for full
 // compatibility with underflow and overflow. This is required
 // by some JCK tests. The limits are based max year values -
 // years that can be represented by max values of d, hh, mm,
 // ss and ms. Also, let GregorianCalendar handle the default
 // cutover year so that we don't need to worry about the
 // transition here.
 if (y == 1582 || y > 280000000 || y < -280000000) {
 if (tz == null) {
 tz = TimeZone.getTimeZone("GMT");
 }
 GregorianCalendar gc = new GregorianCalendar(tz);
 gc.clear();
 gc.set(GregorianCalendar.MILLISECOND, ms);
 gc.set(y, m-1, d, hh, mm, ss);
 fastTime = gc.getTimeInMillis();
 BaseCalendar cal = getCalendarSystem(fastTime);
 date = (BaseCalendar.Date) cal.getCalendarDate(fastTime, tz);
 return date;
 }

 BaseCalendar cal = getCalendarSystem(y);
 if (cal != getCalendarSystem(date)) {
 date = (BaseCalendar.Date) cal.newCalendarDate(tz);
 date.setNormalizedDate(y, m, d).setTimeOfDay(hh, mm, ss, ms);
 }
 // Perform the GregorianCalendar-style normalization.
 fastTime = cal.getTime(date);

 // In case the normalized date requires the other calendar
 // system, we need to recalculate it using the other one.
 BaseCalendar ncal = getCalendarSystem(fastTime);
 if (ncal != cal) {
 date = (BaseCalendar.Date) ncal.newCalendarDate(tz);
 date.setNormalizedDate(y, m, d).setTimeOfDay(hh, mm, ss, ms);
 fastTime = ncal.getTime(date);
 }
 return date;
 }

 /**
 * Returns the Gregorian or Julian calendar system to use with the
 * given date. Use Gregorian from October 15, 1582.
 *
 * @param year normalized calendar year (not -1900)
 * @return the CalendarSystem to use for the specified date
 */
 private static final BaseCalendar getCalendarSystem(int year) {
 if (year >= 1582) {
 return gcal;
 }
 return getJulianCalendar();
 }

 private static final BaseCalendar getCalendarSystem(long utc) {
 // Quickly check if the time stamp given by `utc' is the Epoch
 // or later. If it's before 1970, we convert the cutover to
 // local time to compare.
 if (utc >= 0
 || utc >= GregorianCalendar.DEFAULT_GREGORIAN_CUTOVER
 - TimeZone.getDefaultRef().getOffset(utc)) {
 return gcal;
 }
 return getJulianCalendar();
 }

 private static final BaseCalendar getCalendarSystem(BaseCalendar.Date cdate) {
 if (jcal == null) {
 return gcal;
 }
 if (cdate.getEra() != null) {
 return jcal;
 }
 return gcal;
 }

 private static final synchronized BaseCalendar getJulianCalendar() {
 if (jcal == null) {
 jcal = (BaseCalendar) CalendarSystem.forName("julian");
 }
 return jcal;
 }

 /**
 * Save the state of this object to a stream (i.e., serialize it).
 *
 * @serialData The value returned by {@code getTime()}
 * is emitted (long). This represents the offset from
 * January 1, 1970, 00:00:00 GMT in milliseconds.
 */
 @java.io.Serial
 private void writeObject(ObjectOutputStream s)
 throws IOException
 {
 s.defaultWriteObject();
 s.writeLong(getTimeImpl());
 }

 /**
 * Reconstitute this object from a stream (i.e., deserialize it).
 */
 @java.io.Serial
 private void readObject(ObjectInputStream s)
 throws IOException, ClassNotFoundException
 {
 s.defaultReadObject();
 fastTime = s.readLong();
 }

 /**
 * Obtains an instance of {@code Date} from an {@code Instant} object.
 * 
 * {@code Instant} uses a precision of nanoseconds, whereas {@code Date}
 * uses a precision of milliseconds. The conversion will truncate any
 * excess precision information as though the amount in nanoseconds was
 * subject to integer division by one million.
 * 
 * {@code Instant} can store points on the time-line further in the future
 * and further in the past than {@code Date}. In this scenario, this method
 * will throw an exception.
 *
 * @param instant the instant to convert
 * @return a {@code Date} representing the same point on the time-line as
 * the provided instant
 * @throws NullPointerException if {@code instant} is null.
 * @throws IllegalArgumentException if the instant is too large to
 * represent as a {@code Date}
 * @since 1.8
 */
 public static Date from(Instant instant) {
 try {
 return new Date(instant.toEpochMilli());
 } catch (ArithmeticException ex) {
 throw new IllegalArgumentException(ex);
 }
 }

 /**
 * Converts this {@code Date} object to an {@code Instant}.
 * 
 * The conversion creates an {@code Instant} that represents the same
 * point on the time-line as this {@code Date}.
 *
 * @return an instant representing the same point on the time-line as
 * this {@code Date} object
 * @since 1.8
 */
 public Instant toInstant() {
 return Instant.ofEpochMilli(getTime());
 }
}

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