Quelle Calendar.java Sprache: JAVA

/*
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/*
* (C) Copyright Taligent, Inc. 1996-1998 - All Rights Reserved
* (C) Copyright IBM Corp. 1996-1998 - All Rights Reserved
*
* The original version of this source code and documentation is copyrighted
* and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These
* materials are provided under terms of a License Agreement between Taligent
* and Sun. This technology is protected by multiple US and International
* patents. This notice and attribution to Taligent may not be removed.
* Taligent is a registered trademark of Taligent, Inc.
*
*/

package java.util;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OptionalDataException;
import java.io.Serializable;
import java.security.AccessControlContext;
import java.security.AccessController;
import java.security.PermissionCollection;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.security.ProtectionDomain;
import java.text.DateFormat;
import java.text.DateFormatSymbols;
import java.time.Instant;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import sun.util.BuddhistCalendar;
import sun.util.calendar.ZoneInfo;
import sun.util.locale.provider.CalendarDataUtility;
import sun.util.locale.provider.LocaleProviderAdapter;
import sun.util.locale.provider.TimeZoneNameUtility;
import sun.util.spi.CalendarProvider;

/**
* The {@code Calendar} class is an abstract class that provides methods
* for converting between a specific instant in time and a set of {@link
* #fields calendar fields} such as {@code YEAR}, {@code MONTH},
* {@code DAY_OF_MONTH}, {@code HOUR}, and so on, and for
* manipulating the calendar fields, such as getting the date of the next
* week. An instant in time can be represented by a millisecond value that is
* an offset from the <a id="Epoch">Epoch</a>, January 1, 1970
* 00:00:00.000 GMT (Gregorian).
*
* The class also provides additional fields and methods for
* implementing a concrete calendar system outside the package. Those
* fields and methods are defined as {@code protected}.
*
* 
* Like other locale-sensitive classes, {@code Calendar} provides a
* class method, {@code getInstance}, for getting a generally useful
* object of this type. {@code Calendar}'s {@code getInstance} method
* returns a {@code Calendar} object whose
* calendar fields have been initialized with the current date and time:
* <blockquote>
* <pre>
* Calendar rightNow = Calendar.getInstance();
* </pre>
* </blockquote>
*
* A {@code Calendar} object can produce all the calendar field values
* needed to implement the date-time formatting for a particular language and
* calendar style (for example, Japanese-Gregorian, Japanese-Traditional).
* {@code Calendar} defines the range of values returned by
* certain calendar fields, as well as their meaning. For example,
* the first month of the calendar system has value <code>MONTH ==
* JANUARY</code> for all calendars. Other values are defined by the
* concrete subclass, such as {@code ERA}. See individual field
* documentation and subclass documentation for details.
*
* <h2>Getting and Setting Calendar Field Values</h2>
*
* The calendar field values can be set by calling the {@code set}
* methods. Any field values set in a {@code Calendar} will not be
* interpreted until it needs to calculate its time value (milliseconds from
* the Epoch) or values of the calendar fields. Calling the
* {@code get}, {@code getTimeInMillis}, {@code getTime},
* {@code add} and {@code roll} involves such calculation.
*
* <h3>Leniency</h3>
*
* {@code Calendar} has two modes for interpreting the calendar
* fields, lenient and non-lenient. When a
* {@code Calendar} is in lenient mode, it accepts a wider range of
* calendar field values than it produces. When a {@code Calendar}
* recomputes calendar field values for return by {@code get()}, all of
* the calendar fields are normalized. For example, a lenient
* {@code GregorianCalendar} interprets {@code MONTH == JANUARY},
* {@code DAY_OF_MONTH == 32} as February 1.
*
* When a {@code Calendar} is in non-lenient mode, it throws an
* exception if there is any inconsistency in its calendar fields. For
* example, a {@code GregorianCalendar} always produces
* {@code DAY_OF_MONTH} values between 1 and the length of the month. A
* non-lenient {@code GregorianCalendar} throws an exception upon
* calculating its time or calendar field values if any out-of-range field
* value has been set.
*
* <h3><a id="first_week">First Week</a></h3>
*
* {@code Calendar} defines a locale-specific seven day week using two
* parameters: the first day of the week and the minimal days in first week
* (from 1 to 7). These numbers are taken from the locale resource data or the
* locale itself when a {@code Calendar} is constructed. If the designated
* locale contains "fw" and/or "rg" <a href="./Locale.html#def_locale_extension">
* Unicode extensions</a>, the first day of the week will be obtained according to
* those extensions. If both "fw" and "rg" are specified, the value from the "fw"
* extension supersedes the implicit one from the "rg" extension.
* They may also be specified explicitly through the methods for setting their
* values.
*
* When setting or getting the {@code WEEK_OF_MONTH} or
* {@code WEEK_OF_YEAR} fields, {@code Calendar} must determine the
* first week of the month or year as a reference point. The first week of a
* month or year is defined as the earliest seven day period beginning on
* {@code getFirstDayOfWeek()} and containing at least
* {@code getMinimalDaysInFirstWeek()} days of that month or year. Weeks
* numbered ..., -1, 0 precede the first week; weeks numbered 2, 3,... follow
* it. Note that the normalized numbering returned by {@code get()} may be
* different. For example, a specific {@code Calendar} subclass may
* designate the week before week 1 of a year as week <code>n</code> of
* the previous year.
*
* <h3>Calendar Fields Resolution</h3>
*
* When computing a date and time from the calendar fields, there
* may be insufficient information for the computation (such as only
* year and month with no day of month), or there may be inconsistent
* information (such as Tuesday, July 15, 1996 (Gregorian) -- July 15,
* 1996 is actually a Monday). {@code Calendar} will resolve
* calendar field values to determine the date and time in the
* following way.
*
* <a id="resolution">If there is any conflict in calendar field values,
* {@code Calendar} gives priorities to calendar fields that have been set
* more recently.</a> The following are the default combinations of the
* calendar fields. The most recent combination, as determined by the
* most recently set single field, will be used.
*
* <a id="date_resolution">For the date fields</a>:
* <blockquote>
* <pre>
* YEAR + MONTH + DAY_OF_MONTH
* YEAR + MONTH + WEEK_OF_MONTH + DAY_OF_WEEK
* YEAR + MONTH + DAY_OF_WEEK_IN_MONTH + DAY_OF_WEEK
* YEAR + DAY_OF_YEAR
* YEAR + DAY_OF_WEEK + WEEK_OF_YEAR
* </pre></blockquote>
*
* <a id="time_resolution">For the time of day fields</a>:
* <blockquote>
* <pre>
* HOUR_OF_DAY
* AM_PM + HOUR
* </pre></blockquote>
*
* If there are any calendar fields whose values haven't been set in the selected
* field combination, {@code Calendar} uses their default values. The default
* value of each field may vary by concrete calendar systems. For example, in
* {@code GregorianCalendar}, the default of a field is the same as that
* of the start of the Epoch: i.e., {@code YEAR = 1970}, <code>MONTH =
* JANUARY</code>, {@code DAY_OF_MONTH = 1}, etc.
*
* 
* Note: There are certain possible ambiguities in
* interpretation of certain singular times, which are resolved in the
* following ways:
* <ol>
* <li> 23:59 is the last minute of the day and 00:00 is the first
* minute of the next day. Thus, 23:59 on Dec 31, 1999 < 00:00 on
* Jan 1, 2000 < 00:01 on Jan 1, 2000.
*
* <li> Although historically not precise, midnight also belongs to "am",
* and noon belongs to "pm", so on the same day,
* 12:00 am (midnight) < 12:01 am, and 12:00 pm (noon) < 12:01 pm
* </ol>
*
* 
* The date or time format strings are not part of the definition of a
* calendar, as those must be modifiable or overridable by the user at
* runtime. Use {@link DateFormat}
* to format dates.
*
* <h3>Field Manipulation</h3>
*
* The calendar fields can be changed using three methods:
* {@code set()}, {@code add()}, and {@code roll()}.
*
* {@code set(f, value)} changes calendar field
* {@code f} to {@code value}. In addition, it sets an
* internal member variable to indicate that calendar field {@code f} has
* been changed. Although calendar field {@code f} is changed immediately,
* the calendar's time value in milliseconds is not recomputed until the next call to
* {@code get()}, {@code getTime()}, {@code getTimeInMillis()},
* {@code add()}, or {@code roll()} is made. Thus, multiple calls to
* {@code set()} do not trigger multiple, unnecessary
* computations. As a result of changing a calendar field using
* {@code set()}, other calendar fields may also change, depending on the
* calendar field, the calendar field value, and the calendar system. In addition,
* {@code get(f)} will not necessarily return {@code value} set by
* the call to the {@code set} method
* after the calendar fields have been recomputed. The specifics are determined by
* the concrete calendar class.
*
* Example: Consider a {@code GregorianCalendar}
* originally set to August 31, 1999. Calling <code>set(Calendar.MONTH,
* Calendar.SEPTEMBER)</code> sets the date to September 31,
* 1999. This is a temporary internal representation that resolves to
* October 1, 1999 if {@code getTime()} is then called. However, a
* call to {@code set(Calendar.DAY_OF_MONTH, 30)} before the call to
* {@code getTime()} sets the date to September 30, 1999, since
* no recomputation occurs after {@code set()} itself.
*
* {@code add(f, delta)} adds {@code delta}
* to field {@code f}. This is equivalent to calling <code>set(f,
* get(f) + delta)</code> with two adjustments:
*
* <blockquote>
* Add rule 1. The value of field {@code f}
* after the call minus the value of field {@code f} before the
* call is {@code delta}, modulo any overflow that has occurred in
* field {@code f}. Overflow occurs when a field value exceeds its
* range and, as a result, the next larger field is incremented or
* decremented and the field value is adjusted back into its range.
*
* Add rule 2. If a smaller field is expected to be
* invariant, but it is impossible for it to be equal to its
* prior value because of changes in its minimum or maximum after field
* {@code f} is changed or other constraints, such as time zone
* offset changes, then its value is adjusted to be as close
* as possible to its expected value. A smaller field represents a
* smaller unit of time. {@code HOUR} is a smaller field than
* {@code DAY_OF_MONTH}. No adjustment is made to smaller fields
* that are not expected to be invariant. The calendar system
* determines what fields are expected to be invariant.
* </blockquote>
*
* In addition, unlike {@code set()}, {@code add()} forces
* an immediate recomputation of the calendar's milliseconds and all
* fields.
*
* Example: Consider a {@code GregorianCalendar}
* originally set to August 31, 1999. Calling <code>add(Calendar.MONTH,
* 13)</code> sets the calendar to September 30, 2000. Add rule
* 1 sets the {@code MONTH} field to September, since
* adding 13 months to August gives September of the next year. Since
* {@code DAY_OF_MONTH} cannot be 31 in September in a
* {@code GregorianCalendar}, add rule 2 sets the
* {@code DAY_OF_MONTH} to 30, the closest possible value. Although
* it is a smaller field, {@code DAY_OF_WEEK} is not adjusted by
* rule 2, since it is expected to change when the month changes in a
* {@code GregorianCalendar}.
*
* {@code roll(f, delta)} adds
* {@code delta} to field {@code f} without changing larger
* fields. This is equivalent to calling {@code add(f, delta)} with
* the following adjustment:
*
* <blockquote>
* Roll rule. Larger fields are unchanged after the
* call. A larger field represents a larger unit of
* time. {@code DAY_OF_MONTH} is a larger field than
* {@code HOUR}.
* </blockquote>
*
* Example: See {@link java.util.GregorianCalendar#roll(int, int)}.
*
* Usage model. To motivate the behavior of
* {@code add()} and {@code roll()}, consider a user interface
* component with increment and decrement buttons for the month, day, and
* year, and an underlying {@code GregorianCalendar}. If the
* interface reads January 31, 1999 and the user presses the month
* increment button, what should it read? If the underlying
* implementation uses {@code set()}, it might read March 3, 1999. A
* better result would be February 28, 1999. Furthermore, if the user
* presses the month increment button again, it should read March 31,
* 1999, not March 28, 1999. By saving the original date and using either
* {@code add()} or {@code roll()}, depending on whether larger
* fields should be affected, the user interface can behave as most users
* will intuitively expect.
*
* @see java.lang.System#currentTimeMillis()
* @see Date
* @see GregorianCalendar
* @see TimeZone
* @see java.text.DateFormat
* @author Mark Davis, David Goldsmith, Chen-Lieh Huang, Alan Liu
* @since 1.1
*/
public abstract class Calendar implements Serializable, Cloneable, Comparable<Calendar> {

 // Data flow in Calendar
 // ---------------------

 // The current time is represented in two ways by Calendar: as UTC
 // milliseconds from the epoch (1 January 1970 0:00 UTC), and as local
 // fields such as MONTH, HOUR, AM_PM, etc. It is possible to compute the
 // millis from the fields, and vice versa. The data needed to do this
 // conversion is encapsulated by a TimeZone object owned by the Calendar.
 // The data provided by the TimeZone object may also be overridden if the
 // user sets the ZONE_OFFSET and/or DST_OFFSET fields directly. The class
 // keeps track of what information was most recently set by the caller, and
 // uses that to compute any other information as needed.

 // If the user sets the fields using set(), the data flow is as follows.
 // This is implemented by the Calendar subclass's computeTime() method.
 // During this process, certain fields may be ignored. The disambiguation
 // algorithm for resolving which fields to pay attention to is described
 // in the class documentation.

 // local fields (YEAR, MONTH, DATE, HOUR, MINUTE, etc.)
 // |
 // | Using Calendar-specific algorithm
 // V
 // local standard millis
 // |
 // | Using TimeZone or user-set ZONE_OFFSET / DST_OFFSET
 // V
 // UTC millis (in time data member)

 // If the user sets the UTC millis using setTime() or setTimeInMillis(),
 // the data flow is as follows. This is implemented by the Calendar
 // subclass's computeFields() method.

 // UTC millis (in time data member)
 // |
 // | Using TimeZone getOffset()
 // V
 // local standard millis
 // |
 // | Using Calendar-specific algorithm
 // V
 // local fields (YEAR, MONTH, DATE, HOUR, MINUTE, etc.)

 // In general, a round trip from fields, through local and UTC millis, and
 // back out to fields is made when necessary. This is implemented by the
 // complete() method. Resolving a partial set of fields into a UTC millis
 // value allows all remaining fields to be generated from that value. If
 // the Calendar is lenient, the fields are also renormalized to standard
 // ranges when they are regenerated.

 /**
 * Field number for {@code get} and {@code set} indicating the
 * era, e.g., AD or BC in the Julian calendar. This is a calendar-specific
 * value; see subclass documentation.
 *
 * @see GregorianCalendar#AD
 * @see GregorianCalendar#BC
 */
 public static final int ERA = 0;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * year. This is a calendar-specific value; see subclass documentation.
 */
 public static final int YEAR = 1;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * month. This is a calendar-specific value. The first month of
 * the year in the Gregorian and Julian calendars is
 * {@code JANUARY} which is 0; the last depends on the number
 * of months in a year.
 *
 * @see #JANUARY
 * @see #FEBRUARY
 * @see #MARCH
 * @see #APRIL
 * @see #MAY
 * @see #JUNE
 * @see #JULY
 * @see #AUGUST
 * @see #SEPTEMBER
 * @see #OCTOBER
 * @see #NOVEMBER
 * @see #DECEMBER
 * @see #UNDECIMBER
 */
 public static final int MONTH = 2;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * week number within the current year. The first week of the year, as
 * defined by {@code getFirstDayOfWeek()} and
 * {@code getMinimalDaysInFirstWeek()}, has value 1. Subclasses define
 * the value of {@code WEEK_OF_YEAR} for days before the first week of
 * the year.
 *
 * @see #getFirstDayOfWeek
 * @see #getMinimalDaysInFirstWeek
 */
 public static final int WEEK_OF_YEAR = 3;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * week number within the current month. The first week of the month, as
 * defined by {@code getFirstDayOfWeek()} and
 * {@code getMinimalDaysInFirstWeek()}, has value 1. Subclasses define
 * the value of {@code WEEK_OF_MONTH} for days before the first week of
 * the month.
 *
 * @see #getFirstDayOfWeek
 * @see #getMinimalDaysInFirstWeek
 */
 public static final int WEEK_OF_MONTH = 4;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * day of the month. This is a synonym for {@code DAY_OF_MONTH}.
 * The first day of the month has value 1.
 *
 * @see #DAY_OF_MONTH
 */
 public static final int DATE = 5;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * day of the month. This is a synonym for {@code DATE}.
 * The first day of the month has value 1.
 *
 * @see #DATE
 */
 public static final int DAY_OF_MONTH = 5;

 /**
 * Field number for {@code get} and {@code set} indicating the day
 * number within the current year. The first day of the year has value 1.
 */
 public static final int DAY_OF_YEAR = 6;

 /**
 * Field number for {@code get} and {@code set} indicating the day
 * of the week. This field takes values {@code SUNDAY},
 * {@code MONDAY}, {@code TUESDAY}, {@code WEDNESDAY},
 * {@code THURSDAY}, {@code FRIDAY}, and {@code SATURDAY}.
 *
 * @see #SUNDAY
 * @see #MONDAY
 * @see #TUESDAY
 * @see #WEDNESDAY
 * @see #THURSDAY
 * @see #FRIDAY
 * @see #SATURDAY
 */
 public static final int DAY_OF_WEEK = 7;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * ordinal number of the day of the week within the current month. Together
 * with the {@code DAY_OF_WEEK} field, this uniquely specifies a day
 * within a month. Unlike {@code WEEK_OF_MONTH} and
 * {@code WEEK_OF_YEAR}, this field's value does not depend on
 * {@code getFirstDayOfWeek()} or
 * {@code getMinimalDaysInFirstWeek()}. {@code DAY_OF_MONTH 1}
 * through {@code 7} always correspond to <code>DAY_OF_WEEK_IN_MONTH
 * 1</code>; {@code 8} through {@code 14} correspond to
 * {@code DAY_OF_WEEK_IN_MONTH 2}, and so on.
 * {@code DAY_OF_WEEK_IN_MONTH 0} indicates the week before
 * {@code DAY_OF_WEEK_IN_MONTH 1}. Negative values count back from the
 * end of the month, so the last Sunday of a month is specified as
 * {@code DAY_OF_WEEK = SUNDAY, DAY_OF_WEEK_IN_MONTH = -1}. Because
 * negative values count backward they will usually be aligned differently
 * within the month than positive values. For example, if a month has 31
 * days, {@code DAY_OF_WEEK_IN_MONTH -1} will overlap
 * {@code DAY_OF_WEEK_IN_MONTH 5} and the end of {@code 4}.
 *
 * @see #DAY_OF_WEEK
 * @see #WEEK_OF_MONTH
 */
 public static final int DAY_OF_WEEK_IN_MONTH = 8;

 /**
 * Field number for {@code get} and {@code set} indicating
 * whether the {@code HOUR} is before or after noon.
 * E.g., at 10:04:15.250 PM the {@code AM_PM} is {@code PM}.
 *
 * @see #AM
 * @see #PM
 * @see #HOUR
 */
 public static final int AM_PM = 9;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * hour of the morning or afternoon. {@code HOUR} is used for the
 * 12-hour clock (0 - 11). Noon and midnight are represented by 0, not by 12.
 * E.g., at 10:04:15.250 PM the {@code HOUR} is 10.
 *
 * @see #AM_PM
 * @see #HOUR_OF_DAY
 */
 public static final int HOUR = 10;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * hour of the day. {@code HOUR_OF_DAY} is used for the 24-hour clock.
 * E.g., at 10:04:15.250 PM the {@code HOUR_OF_DAY} is 22.
 *
 * @see #HOUR
 */
 public static final int HOUR_OF_DAY = 11;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * minute within the hour.
 * E.g., at 10:04:15.250 PM the {@code MINUTE} is 4.
 */
 public static final int MINUTE = 12;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * second within the minute.
 * E.g., at 10:04:15.250 PM the {@code SECOND} is 15.
 */
 public static final int SECOND = 13;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * millisecond within the second.
 * E.g., at 10:04:15.250 PM the {@code MILLISECOND} is 250.
 */
 public static final int MILLISECOND = 14;

 /**
 * Field number for {@code get} and {@code set}
 * indicating the raw offset from GMT in milliseconds.
 * 
 * This field reflects the correct GMT offset value of the time
 * zone of this {@code Calendar} if the
 * {@code TimeZone} implementation subclass supports
 * historical GMT offset changes.
 */
 public static final int ZONE_OFFSET = 15;

 /**
 * Field number for {@code get} and {@code set} indicating the
 * daylight saving offset in milliseconds.
 * 
 * This field reflects the correct daylight saving offset value of
 * the time zone of this {@code Calendar} if the
 * {@code TimeZone} implementation subclass supports
 * historical Daylight Saving Time schedule changes.
 */
 public static final int DST_OFFSET = 16;

 /**
 * The number of distinct fields recognized by {@code get} and {@code set}.
 * Field numbers range from {@code 0..FIELD_COUNT-1}.
 */
 public static final int FIELD_COUNT = 17;

 /**
 * Value of the {@link #DAY_OF_WEEK} field indicating
 * Sunday.
 */
 public static final int SUNDAY = 1;

 /**
 * Value of the {@link #DAY_OF_WEEK} field indicating
 * Monday.
 */
 public static final int MONDAY = 2;

 /**
 * Value of the {@link #DAY_OF_WEEK} field indicating
 * Tuesday.
 */
 public static final int TUESDAY = 3;

 /**
 * Value of the {@link #DAY_OF_WEEK} field indicating
 * Wednesday.
 */
 public static final int WEDNESDAY = 4;

 /**
 * Value of the {@link #DAY_OF_WEEK} field indicating
 * Thursday.
 */
 public static final int THURSDAY = 5;

 /**
 * Value of the {@link #DAY_OF_WEEK} field indicating
 * Friday.
 */
 public static final int FRIDAY = 6;

 /**
 * Value of the {@link #DAY_OF_WEEK} field indicating
 * Saturday.
 */
 public static final int SATURDAY = 7;

 /**
 * Value of the {@link #MONTH} field indicating the
 * first month of the year in the Gregorian and Julian calendars.
 */
 public static final int JANUARY = 0;

 /**
 * Value of the {@link #MONTH} field indicating the
 * second month of the year in the Gregorian and Julian calendars.
 */
 public static final int FEBRUARY = 1;

 /**
 * Value of the {@link #MONTH} field indicating the
 * third month of the year in the Gregorian and Julian calendars.
 */
 public static final int MARCH = 2;

 /**
 * Value of the {@link #MONTH} field indicating the
 * fourth month of the year in the Gregorian and Julian calendars.
 */
 public static final int APRIL = 3;

 /**
 * Value of the {@link #MONTH} field indicating the
 * fifth month of the year in the Gregorian and Julian calendars.
 */
 public static final int MAY = 4;

 /**
 * Value of the {@link #MONTH} field indicating the
 * sixth month of the year in the Gregorian and Julian calendars.
 */
 public static final int JUNE = 5;

 /**
 * Value of the {@link #MONTH} field indicating the
 * seventh month of the year in the Gregorian and Julian calendars.
 */
 public static final int JULY = 6;

 /**
 * Value of the {@link #MONTH} field indicating the
 * eighth month of the year in the Gregorian and Julian calendars.
 */
 public static final int AUGUST = 7;

 /**
 * Value of the {@link #MONTH} field indicating the
 * ninth month of the year in the Gregorian and Julian calendars.
 */
 public static final int SEPTEMBER = 8;

 /**
 * Value of the {@link #MONTH} field indicating the
 * tenth month of the year in the Gregorian and Julian calendars.
 */
 public static final int OCTOBER = 9;

 /**
 * Value of the {@link #MONTH} field indicating the
 * eleventh month of the year in the Gregorian and Julian calendars.
 */
 public static final int NOVEMBER = 10;

 /**
 * Value of the {@link #MONTH} field indicating the
 * twelfth month of the year in the Gregorian and Julian calendars.
 */
 public static final int DECEMBER = 11;

 /**
 * Value of the {@link #MONTH} field indicating the
 * thirteenth month of the year. Although {@code GregorianCalendar}
 * does not use this value, lunar calendars do.
 */
 public static final int UNDECIMBER = 12;

 /**
 * Value of the {@link #AM_PM} field indicating the
 * period of the day from midnight to just before noon.
 */
 public static final int AM = 0;

 /**
 * Value of the {@link #AM_PM} field indicating the
 * period of the day from noon to just before midnight.
 */
 public static final int PM = 1;

 /**
 * A style specifier for {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} indicating names in all styles, such as
 * "January" and "Jan".
 *
 * @see #SHORT_FORMAT
 * @see #LONG_FORMAT
 * @see #SHORT_STANDALONE
 * @see #LONG_STANDALONE
 * @see #SHORT
 * @see #LONG
 * @since 1.6
 */
 public static final int ALL_STYLES = 0;

 static final int STANDALONE_MASK = 0x8000;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} equivalent to {@link #SHORT_FORMAT}.
 *
 * @see #SHORT_STANDALONE
 * @see #LONG
 * @since 1.6
 */
 public static final int SHORT = 1;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} equivalent to {@link #LONG_FORMAT}.
 *
 * @see #LONG_STANDALONE
 * @see #SHORT
 * @since 1.6
 */
 public static final int LONG = 2;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} indicating a narrow name used for format. Narrow names
 * are typically single character strings, such as "M" for Monday.
 *
 * @see #NARROW_STANDALONE
 * @see #SHORT_FORMAT
 * @see #LONG_FORMAT
 * @since 1.8
 */
 public static final int NARROW_FORMAT = 4;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} indicating a narrow name independently. Narrow names
 * are typically single character strings, such as "M" for Monday.
 *
 * @see #NARROW_FORMAT
 * @see #SHORT_STANDALONE
 * @see #LONG_STANDALONE
 * @since 1.8
 */
 public static final int NARROW_STANDALONE = NARROW_FORMAT | STANDALONE_MASK;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} indicating a short name used for format.
 *
 * @see #SHORT_STANDALONE
 * @see #LONG_FORMAT
 * @see #LONG_STANDALONE
 * @since 1.8
 */
 public static final int SHORT_FORMAT = 1;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} indicating a long name used for format.
 *
 * @see #LONG_STANDALONE
 * @see #SHORT_FORMAT
 * @see #SHORT_STANDALONE
 * @since 1.8
 */
 public static final int LONG_FORMAT = 2;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} indicating a short name used independently,
 * such as a month abbreviation as calendar headers.
 *
 * @see #SHORT_FORMAT
 * @see #LONG_FORMAT
 * @see #LONG_STANDALONE
 * @since 1.8
 */
 public static final int SHORT_STANDALONE = SHORT | STANDALONE_MASK;

 /**
 * A style specifier for {@link #getDisplayName(int, int, Locale)
 * getDisplayName} and {@link #getDisplayNames(int, int, Locale)
 * getDisplayNames} indicating a long name used independently,
 * such as a month name as calendar headers.
 *
 * @see #LONG_FORMAT
 * @see #SHORT_FORMAT
 * @see #SHORT_STANDALONE
 * @since 1.8
 */
 public static final int LONG_STANDALONE = LONG | STANDALONE_MASK;

 // Internal notes:
 // Calendar contains two kinds of time representations: current "time" in
 // milliseconds, and a set of calendar "fields" representing the current time.
 // The two representations are usually in sync, but can get out of sync
 // as follows.
 // 1. Initially, no fields are set, and the time is invalid.
 // 2. If the time is set, all fields are computed and in sync.
 // 3. If a single field is set, the time is invalid.
 // Recomputation of the time and fields happens when the object needs
 // to return a result to the user, or use a result for a computation.

 /**
 * The calendar field values for the currently set time for this calendar.
 * This is an array of {@code FIELD_COUNT} integers, with index values
 * {@code ERA} through {@code DST_OFFSET}.
 * @serial
 */
 @SuppressWarnings("ProtectedField")
 protected int fields[];

 /**
 * The flags which tell if a specified calendar field for the calendar is set.
 * A new object has no fields set. After the first call to a method
 * which generates the fields, they all remain set after that.
 * This is an array of {@code FIELD_COUNT} booleans, with index values
 * {@code ERA} through {@code DST_OFFSET}.
 * @serial
 */
 @SuppressWarnings("ProtectedField")
 protected boolean isSet[];

 /**
 * Pseudo-time-stamps which specify when each field was set. There
 * are two special values, UNSET and COMPUTED. Values from
 * MINIMUM_USER_SET to Integer.MAX_VALUE are legal user set values.
 */
 private transient int stamp[];

 /**
 * The currently set time for this calendar, expressed in milliseconds after
 * January 1, 1970, 0:00:00 GMT.
 * @see #isTimeSet
 * @serial
 */
 @SuppressWarnings("ProtectedField")
 protected long time;

 /**
 * True if then the value of {@code time} is valid.
 * The time is made invalid by a change to an item of {@code field[]}.
 * @see #time
 * @serial
 */
 @SuppressWarnings("ProtectedField")
 protected boolean isTimeSet;

 /**
 * True if {@code fields[]} are in sync with the currently set time.
 * If false, then the next attempt to get the value of a field will
 * force a recomputation of all fields from the current value of
 * {@code time}.
 * @serial
 */
 @SuppressWarnings("ProtectedField")
 protected boolean areFieldsSet;

 /**
 * True if all fields have been set.
 * @serial
 */
 transient boolean areAllFieldsSet;

 /**
 * {@code True} if this calendar allows out-of-range field values during computation
 * of {@code time} from {@code fields[]}.
 * @see #setLenient
 * @see #isLenient
 * @serial
 */
 private boolean lenient = true;

 /**
 * The {@code TimeZone} used by this calendar. {@code Calendar}
 * uses the time zone data to translate between locale and GMT time.
 * @serial
 */
 private TimeZone zone;

 /**
 * {@code True} if zone references to a shared TimeZone object.
 */
 private transient boolean sharedZone = false;

 /**
 * The first day of the week, with possible values {@code SUNDAY},
 * {@code MONDAY}, etc. This is a locale-dependent value.
 * @serial
 */
 private int firstDayOfWeek;

 /**
 * The number of days required for the first week in a month or year,
 * with possible values from 1 to 7. This is a locale-dependent value.
 * @serial
 */
 private int minimalDaysInFirstWeek;

 /**
 * Cache to hold the firstDayOfWeek and minimalDaysInFirstWeek
 * of a Locale.
 */
 private static final ConcurrentMap<Locale, int[]> cachedLocaleData
 = new ConcurrentHashMap<>(3);

 // Special values of stamp[]
 /**
 * The corresponding fields[] has no value.
 */
 private static final int UNSET = 0;

 /**
 * The value of the corresponding fields[] has been calculated internally.
 */
 private static final int COMPUTED = 1;

 /**
 * The value of the corresponding fields[] has been set externally. Stamp
 * values which are greater than 1 represents the (pseudo) time when the
 * corresponding fields[] value was set.
 */
 private static final int MINIMUM_USER_STAMP = 2;

 /**
 * The mask value that represents all of the fields.
 */
 static final int ALL_FIELDS = (1 << FIELD_COUNT) - 1;

 /**
 * The next available value for {@code stamp[]}, an internal array.
 * This actually should not be written out to the stream, and will probably
 * be removed from the stream in the near future. In the meantime,
 * a value of {@code MINIMUM_USER_STAMP} should be used.
 * @serial
 */
 private int nextStamp = MINIMUM_USER_STAMP;

 // the internal serial version which says which version was written
 // - 0 (default) for version up to JDK 1.1.5
 // - 1 for version from JDK 1.1.6, which writes a correct 'time' value
 // as well as compatible values for other fields. This is a
 // transitional format.
 // - 2 (not implemented yet) a future version, in which fields[],
 // areFieldsSet, and isTimeSet become transient, and isSet[] is
 // removed. In JDK 1.1.6 we write a format compatible with version 2.
 static final int currentSerialVersion = 1;

 /**
 * The version of the serialized data on the stream. Possible values:
 * <dl>
 * <dt>0 or not present on stream</dt>
 * <dd>
 * JDK 1.1.5 or earlier.
 * </dd>
 * <dt>1</dt>
 * <dd>
 * JDK 1.1.6 or later. Writes a correct 'time' value
 * as well as compatible values for other fields. This is a
 * transitional format.
 * </dd>
 * </dl>
 * When streaming out this class, the most recent format
 * and the highest allowable {@code serialVersionOnStream}
 * is written.
 * @serial
 * @since 1.1.6
 */
 private int serialVersionOnStream = currentSerialVersion;

 // Proclaim serialization compatibility with JDK 1.1
 @java.io.Serial
 static final long serialVersionUID = -1807547505821590642L;

 // Mask values for calendar fields
 @SuppressWarnings("PointlessBitwiseExpression")
 static final int ERA_MASK = (1 << ERA);
 static final int YEAR_MASK = (1 << YEAR);
 static final int MONTH_MASK = (1 << MONTH);
 static final int WEEK_OF_YEAR_MASK = (1 << WEEK_OF_YEAR);
 static final int WEEK_OF_MONTH_MASK = (1 << WEEK_OF_MONTH);
 static final int DAY_OF_MONTH_MASK = (1 << DAY_OF_MONTH);
 static final int DAY_OF_YEAR_MASK = (1 << DAY_OF_YEAR);
 static final int DAY_OF_WEEK_MASK = (1 << DAY_OF_WEEK);
 static final int DAY_OF_WEEK_IN_MONTH_MASK = (1 << DAY_OF_WEEK_IN_MONTH);
 static final int AM_PM_MASK = (1 << AM_PM);
 static final int HOUR_MASK = (1 << HOUR);
 static final int HOUR_OF_DAY_MASK = (1 << HOUR_OF_DAY);
 static final int MINUTE_MASK = (1 << MINUTE);
 static final int SECOND_MASK = (1 << SECOND);
 static final int MILLISECOND_MASK = (1 << MILLISECOND);
 static final int ZONE_OFFSET_MASK = (1 << ZONE_OFFSET);
 static final int DST_OFFSET_MASK = (1 << DST_OFFSET);

 /**
 * {@code Calendar.Builder} is used for creating a {@code Calendar} from
 * various date-time parameters.
 *
 * There are two ways to set a {@code Calendar} to a date-time value. One
 * is to set the instant parameter to a millisecond offset from the <a
 * href="Calendar.html#Epoch">Epoch</a>. The other is to set individual
 * field parameters, such as {@link Calendar#YEAR YEAR}, to their desired
 * values. These two ways can't be mixed. Trying to set both the instant and
 * individual fields will cause an {@link IllegalStateException} to be
 * thrown. However, it is permitted to override previous values of the
 * instant or field parameters.
 *
 * If no enough field parameters are given for determining date and/or
 * time, calendar specific default values are used when building a
 * {@code Calendar}. For example, if the {@link Calendar#YEAR YEAR} value
 * isn't given for the Gregorian calendar, 1970 will be used. If there are
 * any conflicts among field parameters, the <a
 * href="Calendar.html#resolution"> resolution rules</a> are applied.
 * Therefore, the order of field setting matters.
 *
 * In addition to the date-time parameters,
 * the {@linkplain #setLocale(Locale) locale},
 * {@linkplain #setTimeZone(TimeZone) time zone},
 * {@linkplain #setWeekDefinition(int, int) week definition}, and
 * {@linkplain #setLenient(boolean) leniency mode} parameters can be set.
 *
 * Examples
 * The following are sample usages. Sample code assumes that the
 * {@code Calendar} constants are statically imported.
 *
 * The following code produces a {@code Calendar} with date 2012-12-31
 * (Gregorian) because Monday is the first day of a week with the <a
 * href="GregorianCalendar.html#iso8601_compatible_setting"> ISO 8601
 * compatible week parameters</a>.
 * <pre>
 * Calendar cal = new Calendar.Builder().setCalendarType("iso8601")
 * .setWeekDate(2013, 1, MONDAY).build();</pre>
 * The following code produces a Japanese {@code Calendar} with date
 * 1989-01-08 (Gregorian), assuming that the default {@link Calendar#ERA ERA}
 * is Heisei that started on that day.
 * <pre>
 * Calendar cal = new Calendar.Builder().setCalendarType("japanese")
 * .setFields(YEAR, 1, DAY_OF_YEAR, 1).build();</pre>
 *
 * @since 1.8
 * @see Calendar#getInstance(TimeZone, Locale)
 * @see Calendar#fields
 */
 public static class Builder {
 private static final int NFIELDS = FIELD_COUNT + 1; // +1 for WEEK_YEAR
 private static final int WEEK_YEAR = FIELD_COUNT;

 private long instant;
 // Calendar.stamp[] (lower half) and Calendar.fields[] (upper half) combined
 private int[] fields;
 // Pseudo timestamp starting from MINIMUM_USER_STAMP.
 // (COMPUTED is used to indicate that the instant has been set.)
 private int nextStamp;
 // maxFieldIndex keeps the max index of fields which have been set.
 // (WEEK_YEAR is never included.)
 private int maxFieldIndex;
 private String type;
 private TimeZone zone;
 private boolean lenient = true;
 private Locale locale;
 private int firstDayOfWeek, minimalDaysInFirstWeek;

 /**
 * Constructs a {@code Calendar.Builder}.
 */
 public Builder() {
 }

 /**
 * Sets the instant parameter to the given {@code instant} value that is
 * a millisecond offset from <a href="Calendar.html#Epoch">the
 * Epoch</a>.
 *
 * @param instant a millisecond offset from the Epoch
 * @return this {@code Calendar.Builder}
 * @throws IllegalStateException if any of the field parameters have
 * already been set
 * @see Calendar#setTime(Date)
 * @see Calendar#setTimeInMillis(long)
 * @see Calendar#time
 */
 public Builder setInstant(long instant) {
 if (fields != null) {
 throw new IllegalStateException();
 }
 this.instant = instant;
 nextStamp = COMPUTED;
 return this;
 }

 /**
 * Sets the instant parameter to the {@code instant} value given by a
 * {@link Date}. This method is equivalent to a call to
 * {@link #setInstant(long) setInstant(instant.getTime())}.
 *
 * @param instant a {@code Date} representing a millisecond offset from
 * the Epoch
 * @return this {@code Calendar.Builder}
 * @throws NullPointerException if {@code instant} is {@code null}
 * @throws IllegalStateException if any of the field parameters have
 * already been set
 * @see Calendar#setTime(Date)
 * @see Calendar#setTimeInMillis(long)
 * @see Calendar#time
 */
 public Builder setInstant(Date instant) {
 return setInstant(instant.getTime()); // NPE if instant == null
 }

 /**
 * Sets the {@code field} parameter to the given {@code value}.
 * {@code field} is an index to the {@link Calendar#fields}, such as
 * {@link Calendar#DAY_OF_MONTH DAY_OF_MONTH}. Field value validation is
 * not performed in this method. Any out of range values are either
 * normalized in lenient mode or detected as an invalid value in
 * non-lenient mode when building a {@code Calendar}.
 *
 * @param field an index to the {@code Calendar} fields
 * @param value the field value
 * @return this {@code Calendar.Builder}
 * @throws IllegalArgumentException if {@code field} is invalid
 * @throws IllegalStateException if the instant value has already been set,
 * or if fields have been set too many
 * (approximately {@link Integer#MAX_VALUE}) times.
 * @see Calendar#set(int, int)
 */
 public Builder set(int field, int value) {
 // Note: WEEK_YEAR can't be set with this method.
 if (field < 0 || field >= FIELD_COUNT) {
 throw new IllegalArgumentException("field is invalid");
 }
 if (isInstantSet()) {
 throw new IllegalStateException("instant has been set");
 }
 allocateFields();
 internalSet(field, value);
 return this;
 }

 /**
 * Sets field parameters to their values given by
 * {@code fieldValuePairs} that are pairs of a field and its value.
 * For example,
 * <pre>
 * setFields(Calendar.YEAR, 2013,
 * Calendar.MONTH, Calendar.DECEMBER,
 * Calendar.DAY_OF_MONTH, 23);</pre>
 * is equivalent to the sequence of the following
 * {@link #set(int, int) set} calls:
 * <pre>
 * set(Calendar.YEAR, 2013)
 * .set(Calendar.MONTH, Calendar.DECEMBER)
 * .set(Calendar.DAY_OF_MONTH, 23);</pre>
 *
 * @param fieldValuePairs field-value pairs
 * @return this {@code Calendar.Builder}
 * @throws NullPointerException if {@code fieldValuePairs} is {@code null}
 * @throws IllegalArgumentException if any of fields are invalid,
 * or if {@code fieldValuePairs.length} is an odd number.
 * @throws IllegalStateException if the instant value has been set,
 * or if fields have been set too many (approximately
 * {@link Integer#MAX_VALUE}) times.
 */
 public Builder setFields(int... fieldValuePairs) {
 int len = fieldValuePairs.length;
 if ((len % 2) != 0) {
 throw new IllegalArgumentException();
 }
 if (isInstantSet()) {
 throw new IllegalStateException("instant has been set");
 }
 if ((nextStamp + len / 2) < 0) {
 throw new IllegalStateException("stamp counter overflow");
 }
 allocateFields();
 for (int i = 0; i < len; ) {
 int field = fieldValuePairs[i++];
 // Note: WEEK_YEAR can't be set with this method.
 if (field < 0 || field >= FIELD_COUNT) {
 throw new IllegalArgumentException("field is invalid");
 }
 internalSet(field, fieldValuePairs[i++]);
 }
 return this;
 }

 /**
 * Sets the date field parameters to the values given by {@code year},
 * {@code month}, and {@code dayOfMonth}. This method is equivalent to
 * a call to:
 * <pre>
 * setFields(Calendar.YEAR, year,
 * Calendar.MONTH, month,
 * Calendar.DAY_OF_MONTH, dayOfMonth);</pre>
 *
 * @param year the {@link Calendar#YEAR YEAR} value
 * @param month the {@link Calendar#MONTH MONTH} value
 * (the month numbering is 0-based).
 * @param dayOfMonth the {@link Calendar#DAY_OF_MONTH DAY_OF_MONTH} value
 * @return this {@code Calendar.Builder}
 */
 public Builder setDate(int year, int month, int dayOfMonth) {
 return setFields(YEAR, year, MONTH, month, DAY_OF_MONTH, dayOfMonth);
 }

 /**
 * Sets the time of day field parameters to the values given by
 * {@code hourOfDay}, {@code minute}, and {@code second}. This method is
 * equivalent to a call to:
 * <pre>
 * setTimeOfDay(hourOfDay, minute, second, 0);</pre>
 *
 * @param hourOfDay the {@link Calendar#HOUR_OF_DAY HOUR_OF_DAY} value
 * (24-hour clock)
 * @param minute the {@link Calendar#MINUTE MINUTE} value
 * @param second the {@link Calendar#SECOND SECOND} value
 * @return this {@code Calendar.Builder}
 */
 public Builder setTimeOfDay(int hourOfDay, int minute, int second) {
 return setTimeOfDay(hourOfDay, minute, second, 0);
 }

 /**
 * Sets the time of day field parameters to the values given by
 * {@code hourOfDay}, {@code minute}, {@code second}, and
 * {@code millis}. This method is equivalent to a call to:
 * <pre>
 * setFields(Calendar.HOUR_OF_DAY, hourOfDay,
 * Calendar.MINUTE, minute,
 * Calendar.SECOND, second,
 * Calendar.MILLISECOND, millis);</pre>
 *
 * @param hourOfDay the {@link Calendar#HOUR_OF_DAY HOUR_OF_DAY} value
 * (24-hour clock)
 * @param minute the {@link Calendar#MINUTE MINUTE} value
 * @param second the {@link Calendar#SECOND SECOND} value
 * @param millis the {@link Calendar#MILLISECOND MILLISECOND} value
 * @return this {@code Calendar.Builder}
 */
 public Builder setTimeOfDay(int hourOfDay, int minute, int second, int millis) {
 return setFields(HOUR_OF_DAY, hourOfDay, MINUTE, minute,
 SECOND, second, MILLISECOND, millis);
 }

 /**
 * Sets the week-based date parameters to the values with the given
 * date specifiers - week year, week of year, and day of week.
 *
 * If the specified calendar doesn't support week dates, the
 * {@link #build() build} method will throw an {@link IllegalArgumentException}.
 *
 * @param weekYear the week year
 * @param weekOfYear the week number based on {@code weekYear}
 * @param dayOfWeek the day of week value: one of the constants
 * for the {@link Calendar#DAY_OF_WEEK DAY_OF_WEEK} field:
 * {@link Calendar#SUNDAY SUNDAY}, ..., {@link Calendar#SATURDAY SATURDAY}.
 * @return this {@code Calendar.Builder}
 * @see Calendar#setWeekDate(int, int, int)
 * @see Calendar#isWeekDateSupported()
 */
 public Builder setWeekDate(int weekYear, int weekOfYear, int dayOfWeek) {
 allocateFields();
 internalSet(WEEK_YEAR, weekYear);
 internalSet(WEEK_OF_YEAR, weekOfYear);
 internalSet(DAY_OF_WEEK, dayOfWeek);
 return this;
 }

 /**
 * Sets the time zone parameter to the given {@code zone}. If no time
 * zone parameter is given to this {@code Calendar.Builder}, the
 * {@linkplain TimeZone#getDefault() default
 * {@code TimeZone}} will be used in the {@link #build() build}
 * method.
 *
 * @param zone the {@link TimeZone}
 * @return this {@code Calendar.Builder}
 * @throws NullPointerException if {@code zone} is {@code null}
 * @see Calendar#setTimeZone(TimeZone)
 */
 public Builder setTimeZone(TimeZone zone) {
 if (zone == null) {
 throw new NullPointerException();
 }
 this.zone = zone;
 return this;
 }

 /**
 * Sets the lenient mode parameter to the value given by {@code lenient}.
 * If no lenient parameter is given to this {@code Calendar.Builder},
 * lenient mode will be used in the {@link #build() build} method.
 *
 * @param lenient {@code true} for lenient mode;
 * {@code false} for non-lenient mode
 * @return this {@code Calendar.Builder}
 * @see Calendar#setLenient(boolean)
 */
 public Builder setLenient(boolean lenient) {
 this.lenient = lenient;
 return this;
 }

 /**
 * Sets the calendar type parameter to the given {@code type}. The
 * calendar type given by this method has precedence over any explicit
 * or implicit calendar type given by the
 * {@linkplain #setLocale(Locale) locale}.
 *
 * In addition to the available calendar types returned by the
 * {@link Calendar#getAvailableCalendarTypes() Calendar.getAvailableCalendarTypes}
 * method, {@code "gregorian"} and {@code "iso8601"} as aliases of
 * {@code "gregory"} can be used with this method.
 *
 * @param type the calendar type
 * @return this {@code Calendar.Builder}
 * @throws NullPointerException if {@code type} is {@code null}
 * @throws IllegalArgumentException if {@code type} is unknown
 * @throws IllegalStateException if another calendar type has already been set
 * @see Calendar#getCalendarType()
 * @see Calendar#getAvailableCalendarTypes()
 */
 public Builder setCalendarType(String type) {
 if (type.equals("gregorian")) { // NPE if type == null
 type = "gregory";
 }
 if (!Calendar.getAvailableCalendarTypes().contains(type)
 && !type.equals("iso8601")) {
 throw new IllegalArgumentException("unknown calendar type: " + type);
 }
 if (this.type == null) {
 this.type = type;
 } else {
 if (!this.type.equals(type)) {
 throw new IllegalStateException("calendar type override");
 }
 }
 return this;
 }

 /**
 * Sets the locale parameter to the given {@code locale}. If no locale
 * is given to this {@code Calendar.Builder}, the {@linkplain
 * Locale#getDefault(Locale.Category) default {@code Locale}}
 * for {@link Locale.Category#FORMAT} will be used.
 *
 * If no calendar type is explicitly given by a call to the
 * {@link #setCalendarType(String) setCalendarType} method,
 * the {@code Locale} value is used to determine what type of
 * {@code Calendar} to be built.
 *
 * If no week definition parameters are explicitly given by a call to
 * the {@link #setWeekDefinition(int,int) setWeekDefinition} method, the
 * {@code Locale}'s default values are used.
 *
 * @param locale the {@link Locale}
 * @throws NullPointerException if {@code locale} is {@code null}
 * @return this {@code Calendar.Builder}
 * @see Calendar#getInstance(Locale)
 */
 public Builder setLocale(Locale locale) {
 if (locale == null) {
 throw new NullPointerException();
 }
 this.locale = locale;
 return this;
 }

 /**
 * Sets the week definition parameters to the values given by
 * {@code firstDayOfWeek} and {@code minimalDaysInFirstWeek} that are
 * used to determine the <a href="Calendar.html#first_week">first
 * week</a> of a year. The parameters given by this method have
 * precedence over the default values given by the
 * {@linkplain #setLocale(Locale) locale}.
 *
 * @param firstDayOfWeek the first day of a week; one of
 * {@link Calendar#SUNDAY} to {@link Calendar#SATURDAY}
 * @param minimalDaysInFirstWeek the minimal number of days in the first
 * week (1..7)
 * @return this {@code Calendar.Builder}
 * @throws IllegalArgumentException if {@code firstDayOfWeek} or
 * {@code minimalDaysInFirstWeek} is invalid
 * @see Calendar#getFirstDayOfWeek()
 * @see Calendar#getMinimalDaysInFirstWeek()
 */
 public Builder setWeekDefinition(int firstDayOfWeek, int minimalDaysInFirstWeek) {
 if (!isValidWeekParameter(firstDayOfWeek)
 || !isValidWeekParameter(minimalDaysInFirstWeek)) {
 throw new IllegalArgumentException();
 }
 this.firstDayOfWeek = firstDayOfWeek;
 this.minimalDaysInFirstWeek = minimalDaysInFirstWeek;
 return this;
 }

 /**
 * Returns a {@code Calendar} built from the parameters set by the
 * setter methods. The calendar type given by the {@link #setCalendarType(String)
 * setCalendarType} method or the {@linkplain #setLocale(Locale) locale} is
 * used to determine what {@code Calendar} to be created. If no explicit
 * calendar type is given, the locale's default calendar is created.
 *
 * If the calendar type is {@code "iso8601"}, the
 * {@linkplain GregorianCalendar#setGregorianChange(Date) Gregorian change date}
 * of a {@link GregorianCalendar} is set to {@code Date(Long.MIN_VALUE)}
 * to be the proleptic Gregorian calendar. Its week definition
 * parameters are also set to be <a
 * href="GregorianCalendar.html#iso8601_compatible_setting">compatible
 * with the ISO 8601 standard</a>. Note that the
 * {@link GregorianCalendar#getCalendarType() getCalendarType} method of
 * a {@code GregorianCalendar} created with {@code "iso8601"} returns
 * {@code "gregory"}.
 *
 * The default values are used for locale and time zone if these
 * parameters haven't been given explicitly.
 * 
 * If the locale contains the time zone with "tz"
 * <a href="Locale.html#def_locale_extension">Unicode extension</a>,
 * and time zone hasn't been given explicitly, time zone in the locale
 * is used.
 *
 * Any out of range field values are either normalized in lenient
 * mode or detected as an invalid value in non-lenient mode.
 *
 * @return a {@code Calendar} built with parameters of this {@code
 * Calendar.Builder}
 * @throws IllegalArgumentException if the calendar type is unknown, or
 * if any invalid field values are given in non-lenient mode, or
 * if a week date is given for the calendar type that doesn't
 * support week dates.
 * @see Calendar#getInstance(TimeZone, Locale)
 * @see Locale#getDefault(Locale.Category)
 * @see TimeZone#getDefault()
 */
 public Calendar build() {
 if (locale == null) {
 locale = Locale.getDefault();
 }
 if (zone == null) {
 zone = defaultTimeZone(locale);
 }
 if (type == null) {
 type = locale.getUnicodeLocaleType("ca");
 }
 if (type == null) {
 if (locale.getCountry() == "TH"
 && locale.getLanguage() == "th") {
 type = "buddhist";
 } else {
 type = "gregory";
 }
 }
 final Calendar cal = switch (type) {
 case "gregory" -> new GregorianCalendar(zone, locale, true);
 case "iso8601" -> {
 GregorianCalendar gcal = new GregorianCalendar(zone, locale, true);
 // make gcal a proleptic Gregorian
 gcal.setGregorianChange(new Date(Long.MIN_VALUE));
 // and week definition to be compatible with ISO 8601
 setWeekDefinition(MONDAY, 4);
 yield gcal;
 }
 case "buddhist" -> {
 var buddhistCalendar = new BuddhistCalendar(zone, locale);
 buddhistCalendar.clear();
 yield buddhistCalendar;
 }
 case "japanese" -> new JapaneseImperialCalendar(zone, locale, true);
 default -> throw new IllegalArgumentException("unknown calendar type: " + type);
 };
 cal.setLenient(lenient);
 if (firstDayOfWeek != 0) {
 cal.setFirstDayOfWeek(firstDayOfWeek);
 cal.setMinimalDaysInFirstWeek(minimalDaysInFirstWeek);
 }
 if (isInstantSet()) {
 cal.setTimeInMillis(instant);
 cal.complete();
 return cal;
 }

 if (fields != null) {
 boolean weekDate = isSet(WEEK_YEAR)
 && fields[WEEK_YEAR] > fields[YEAR];
 if (weekDate && !cal.isWeekDateSupported()) {
 throw new IllegalArgumentException("week date is unsupported by " + type);
 }

 // Set the fields from the min stamp to the max stamp so that
 // the fields resolution works in the Calendar.
 for (int stamp = MINIMUM_USER_STAMP; stamp < nextStamp; stamp++) {
 for (int index = 0; index <= maxFieldIndex; index++) {
 if (fields[index] == stamp) {
 cal.set(index, fields[NFIELDS + index]);
 break;
 }
 }
 }

 if (weekDate) {
 int weekOfYear = isSet(WEEK_OF_YEAR) ? fields[NFIELDS + WEEK_OF_YEAR] : 1;
 int dayOfWeek = isSet(DAY_OF_WEEK)
 ? fields[NFIELDS + DAY_OF_WEEK] : cal.getFirstDayOfWeek();
 cal.setWeekDate(fields[NFIELDS + WEEK_YEAR], weekOfYear, dayOfWeek);
 }
 cal.complete();
 }

 return cal;
 }

 private void allocateFields() {
 if (fields == null) {
 fields = new int[NFIELDS * 2];
 nextStamp = MINIMUM_USER_STAMP;
 maxFieldIndex = -1;
 }
 }

 private void internalSet(int field, int value) {
 fields[field] = nextStamp++;
 if (nextStamp < 0) {
 throw new IllegalStateException("stamp counter overflow");
 }
 fields[NFIELDS + field] = value;
 if (field > maxFieldIndex && field < WEEK_YEAR) {
 maxFieldIndex = field;
 }
 }

 private boolean isInstantSet() {
 return nextStamp == COMPUTED;
 }

 private boolean isSet(int index) {
 return fields != null && fields[index] > UNSET;
 }

 private boolean isValidWeekParameter(int value) {
 return value > 0 && value <= 7;
 }
 }

 /**
 * Constructs a Calendar with the default time zone
 * and the default {@link java.util.Locale.Category#FORMAT FORMAT}
 * locale.
 * @see TimeZone#getDefault
 */
 protected Calendar()
 {
 this(TimeZone.getDefaultRef(), Locale.getDefault(Locale.Category.FORMAT));
 sharedZone = true;
 }

 /**
 * Constructs a calendar with the specified time zone and locale.
 *
 * @param zone the time zone to use
 * @param aLocale the locale for the week data
 */
 protected Calendar(TimeZone zone, Locale aLocale)
 {
 fields = new int[FIELD_COUNT];
 isSet = new boolean[FIELD_COUNT];
--> --------------------

--> maximum size reached

--> --------------------

Messung V0.5

¤ Dauer der Verarbeitung: 0.19 Sekunden ¤

Wurzel

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Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

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