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	/*
	* Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	/*
	* (C) Copyright Taligent, Inc. 1996 - All Rights Reserved
	* (C) Copyright IBM Corp. 1996 - 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.ObjectInputStream;
	import java.io.ObjectOutputStream;
	import java.io.IOException;
	import java.io.InvalidObjectException;
	import sun.util.calendar.CalendarSystem;
	import sun.util.calendar.CalendarUtils;
	import sun.util.calendar.BaseCalendar;
	import sun.util.calendar.Gregorian;

	/**
	* <code>SimpleTimeZone</code> is a concrete subclass of <code>TimeZone</code>
	* that represents a time zone for use with a Gregorian calendar.
	* The class holds an offset from GMT, called <em>raw offset</em>, and start
	* and end rules for a daylight saving time schedule. Since it only holds
	* single values for each, it cannot handle historical changes in the offset
	* from GMT and the daylight saving schedule, except that the {@link
	* #setStartYear setStartYear} method can specify the year when the daylight
	* saving time schedule starts in effect.
	* <p>
	* To construct a <code>SimpleTimeZone</code> with a daylight saving time
	* schedule, the schedule can be described with a set of rules,
	* <em>start-rule</em> and <em>end-rule</em>. A day when daylight saving time
	* starts or ends is specified by a combination of <em>month</em>,
	* <em>day-of-month</em>, and <em>day-of-week</em> values. The <em>month</em>
	* value is represented by a Calendar {@link Calendar#MONTH MONTH} field
	* value, such as {@link Calendar#MARCH}. The <em>day-of-week</em> value is
	* represented by a Calendar {@link Calendar#DAY_OF_WEEK DAY_OF_WEEK} value,
	* such as {@link Calendar#SUNDAY SUNDAY}. The meanings of value combinations
	* are as follows.
	*
	* <ul>
	* <li><b>Exact day of month</b><br>
	* To specify an exact day of month, set the <em>month</em> and
	* <em>day-of-month</em> to an exact value, and <em>day-of-week</em> to zero. For
	* example, to specify March 1, set the <em>month</em> to {@link Calendar#MARCH
	* MARCH}, <em>day-of-month</em> to 1, and <em>day-of-week</em> to 0.</li>
	*
	* <li><b>Day of week on or after day of month</b><br>
	* To specify a day of week on or after an exact day of month, set the
	* <em>month</em> to an exact month value, <em>day-of-month</em> to the day on
	* or after which the rule is applied, and <em>day-of-week</em> to a negative {@link
	* Calendar#DAY_OF_WEEK DAY_OF_WEEK} field value. For example, to specify the
	* second Sunday of April, set <em>month</em> to {@link Calendar#APRIL APRIL},
	* <em>day-of-month</em> to 8, and <em>day-of-week</em> to <code>-</code>{@link
	* Calendar#SUNDAY SUNDAY}.</li>
	*
	* <li><b>Day of week on or before day of month</b><br>
	* To specify a day of the week on or before an exact day of the month, set
	* <em>day-of-month</em> and <em>day-of-week</em> to a negative value. For
	* example, to specify the last Wednesday on or before the 21st of March, set
	* <em>month</em> to {@link Calendar#MARCH MARCH}, <em>day-of-month</em> is -21
	* and <em>day-of-week</em> is <code>-</code>{@link Calendar#WEDNESDAY WEDNESDAY}. </li>
	*
	* <li><b>Last day-of-week of month</b><br>
	* To specify, the last day-of-week of the month, set <em>day-of-week</em> to a
	* {@link Calendar#DAY_OF_WEEK DAY_OF_WEEK} value and <em>day-of-month</em> to
	* -1. For example, to specify the last Sunday of October, set <em>month</em>
	* to {@link Calendar#OCTOBER OCTOBER}, <em>day-of-week</em> to {@link
	* Calendar#SUNDAY SUNDAY} and <em>day-of-month</em> to -1. </li>
	*
	* </ul>
	* The time of the day at which daylight saving time starts or ends is
	* specified by a millisecond value within the day. There are three kinds of
	* <em>mode</em>s to specify the time: {@link #WALL_TIME}, {@link
	* #STANDARD_TIME} and {@link #UTC_TIME}. For example, if daylight
	* saving time ends
	* at 2:00 am in the wall clock time, it can be specified by 7200000
	* milliseconds in the {@link #WALL_TIME} mode. In this case, the wall clock time
	* for an <em>end-rule</em> means the same thing as the daylight time.
	* <p>
	* The following are examples of parameters for constructing time zone objects.
	* <pre><code>
	* // Base GMT offset: -8:00
	* // DST starts: at 2:00am in standard time
	* // on the first Sunday in April
	* // DST ends: at 2:00am in daylight time
	* // on the last Sunday in October
	* // Save: 1 hour
	* SimpleTimeZone(-28800000,
	* "America/Los_Angeles",
	* Calendar.APRIL, 1, -Calendar.SUNDAY,
	* 7200000,
	* Calendar.OCTOBER, -1, Calendar.SUNDAY,
	* 7200000,
	* 3600000)
	*
	* // Base GMT offset: +1:00
	* // DST starts: at 1:00am in UTC time
	* // on the last Sunday in March
	* // DST ends: at 1:00am in UTC time
	* // on the last Sunday in October
	* // Save: 1 hour
	* SimpleTimeZone(3600000,
	* "Europe/Paris",
	* Calendar.MARCH, -1, Calendar.SUNDAY,
	* 3600000, SimpleTimeZone.UTC_TIME,
	* Calendar.OCTOBER, -1, Calendar.SUNDAY,
	* 3600000, SimpleTimeZone.UTC_TIME,
	* 3600000)
	* </code></pre>
	* These parameter rules are also applicable to the set rule methods, such as
	* <code>setStartRule</code>.
	*
	* @since 1.1
	* @see Calendar
	* @see GregorianCalendar
	* @see TimeZone
	* @author David Goldsmith, Mark Davis, Chen-Lieh Huang, Alan Liu
	*/

	public class SimpleTimeZone extends TimeZone {
	/**
	* Constructs a SimpleTimeZone with the given base time zone offset from GMT
	* and time zone ID with no daylight saving time schedule.
	*
	* @param rawOffset The base time zone offset in milliseconds to GMT.
	* @param ID The time zone name that is given to this instance.
	*/
	public SimpleTimeZone(int rawOffset, String ID)
	{
	this.rawOffset = rawOffset;
	setID (ID);
	dstSavings = millisPerHour; // In case user sets rules later
	}

	/**
	* Constructs a SimpleTimeZone with the given base time zone offset from
	* GMT, time zone ID, and rules for starting and ending the daylight
	* time.
	* Both <code>startTime</code> and <code>endTime</code> are specified to be
	* represented in the wall clock time. The amount of daylight saving is
	* assumed to be 3600000 milliseconds (i.e., one hour). This constructor is
	* equivalent to:
	* <pre><code>
	* SimpleTimeZone(rawOffset,
	* ID,
	* startMonth,
	* startDay,
	* startDayOfWeek,
	* startTime,
	* SimpleTimeZone.{@link #WALL_TIME},
	* endMonth,
	* endDay,
	* endDayOfWeek,
	* endTime,
	* SimpleTimeZone.{@link #WALL_TIME},
	* 3600000)
	* </code></pre>
	*
	* @param rawOffset The given base time zone offset from GMT.
	* @param ID The time zone ID which is given to this object.
	* @param startMonth The daylight saving time starting month. Month is
	* a {@link Calendar#MONTH MONTH} field value (0-based. e.g., 0
	* for January).
	* @param startDay The day of the month on which the daylight saving time starts.
	* See the class description for the special cases of this parameter.
	* @param startDayOfWeek The daylight saving time starting day-of-week.
	* See the class description for the special cases of this parameter.
	* @param startTime The daylight saving time starting time in local wall clock
	* time (in milliseconds within the day), which is local
	* standard time in this case.
	* @param endMonth The daylight saving time ending month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 9 for October).
	* @param endDay The day of the month on which the daylight saving time ends.
	* See the class description for the special cases of this parameter.
	* @param endDayOfWeek The daylight saving time ending day-of-week.
	* See the class description for the special cases of this parameter.
	* @param endTime The daylight saving ending time in local wall clock time,
	* (in milliseconds within the day) which is local daylight
	* time in this case.
	* @exception IllegalArgumentException if the month, day, dayOfWeek, or time
	* parameters are out of range for the start or end rule
	*/
	public SimpleTimeZone(int rawOffset, String ID,
	int startMonth, int startDay, int startDayOfWeek, int startTime,
	int endMonth, int endDay, int endDayOfWeek, int endTime)
	{
	this(rawOffset, ID,
	startMonth, startDay, startDayOfWeek, startTime, WALL_TIME,
	endMonth, endDay, endDayOfWeek, endTime, WALL_TIME,
	millisPerHour);
	}

	/**
	* Constructs a SimpleTimeZone with the given base time zone offset from
	* GMT, time zone ID, and rules for starting and ending the daylight
	* time.
	* Both <code>startTime</code> and <code>endTime</code> are assumed to be
	* represented in the wall clock time. This constructor is equivalent to:
	* <pre><code>
	* SimpleTimeZone(rawOffset,
	* ID,
	* startMonth,
	* startDay,
	* startDayOfWeek,
	* startTime,
	* SimpleTimeZone.{@link #WALL_TIME},
	* endMonth,
	* endDay,
	* endDayOfWeek,
	* endTime,
	* SimpleTimeZone.{@link #WALL_TIME},
	* dstSavings)
	* </code></pre>
	*
	* @param rawOffset The given base time zone offset from GMT.
	* @param ID The time zone ID which is given to this object.
	* @param startMonth The daylight saving time starting month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 0 for January).
	* @param startDay The day of the month on which the daylight saving time starts.
	* See the class description for the special cases of this parameter.
	* @param startDayOfWeek The daylight saving time starting day-of-week.
	* See the class description for the special cases of this parameter.
	* @param startTime The daylight saving time starting time in local wall clock
	* time, which is local standard time in this case.
	* @param endMonth The daylight saving time ending month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 9 for October).
	* @param endDay The day of the month on which the daylight saving time ends.
	* See the class description for the special cases of this parameter.
	* @param endDayOfWeek The daylight saving time ending day-of-week.
	* See the class description for the special cases of this parameter.
	* @param endTime The daylight saving ending time in local wall clock time,
	* which is local daylight time in this case.
	* @param dstSavings The amount of time in milliseconds saved during
	* daylight saving time.
	* @exception IllegalArgumentException if the month, day, dayOfWeek, or time
	* parameters are out of range for the start or end rule
	* @since 1.2
	*/
	public SimpleTimeZone(int rawOffset, String ID,
	int startMonth, int startDay, int startDayOfWeek, int startTime,
	int endMonth, int endDay, int endDayOfWeek, int endTime,
	int dstSavings)
	{
	this(rawOffset, ID,
	startMonth, startDay, startDayOfWeek, startTime, WALL_TIME,
	endMonth, endDay, endDayOfWeek, endTime, WALL_TIME,
	dstSavings);
	}

	/**
	* Constructs a SimpleTimeZone with the given base time zone offset from
	* GMT, time zone ID, and rules for starting and ending the daylight
	* time.
	* This constructor takes the full set of the start and end rules
	* parameters, including modes of <code>startTime</code> and
	* <code>endTime</code>. The mode specifies either {@link #WALL_TIME wall
	* time} or {@link #STANDARD_TIME standard time} or {@link #UTC_TIME UTC
	* time}.
	*
	* @param rawOffset The given base time zone offset from GMT.
	* @param ID The time zone ID which is given to this object.
	* @param startMonth The daylight saving time starting month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 0 for January).
	* @param startDay The day of the month on which the daylight saving time starts.
	* See the class description for the special cases of this parameter.
	* @param startDayOfWeek The daylight saving time starting day-of-week.
	* See the class description for the special cases of this parameter.
	* @param startTime The daylight saving time starting time in the time mode
	* specified by <code>startTimeMode</code>.
	* @param startTimeMode The mode of the start time specified by startTime.
	* @param endMonth The daylight saving time ending month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 9 for October).
	* @param endDay The day of the month on which the daylight saving time ends.
	* See the class description for the special cases of this parameter.
	* @param endDayOfWeek The daylight saving time ending day-of-week.
	* See the class description for the special cases of this parameter.
	* @param endTime The daylight saving ending time in time time mode
	* specified by <code>endTimeMode</code>.
	* @param endTimeMode The mode of the end time specified by endTime
	* @param dstSavings The amount of time in milliseconds saved during
	* daylight saving time.
	*
	* @exception IllegalArgumentException if the month, day, dayOfWeek, time more, or
	* time parameters are out of range for the start or end rule, or if a time mode
	* value is invalid.
	*
	* @see #WALL_TIME
	* @see #STANDARD_TIME
	* @see #UTC_TIME
	*
	* @since 1.4
	*/
	public SimpleTimeZone(int rawOffset, String ID,
	int startMonth, int startDay, int startDayOfWeek,
	int startTime, int startTimeMode,
	int endMonth, int endDay, int endDayOfWeek,
	int endTime, int endTimeMode,
	int dstSavings) {

	setID(ID);
	this.rawOffset = rawOffset;
	this.startMonth = startMonth;
	this.startDay = startDay;
	this.startDayOfWeek = startDayOfWeek;
	this.startTime = startTime;
	this.startTimeMode = startTimeMode;
	this.endMonth = endMonth;
	this.endDay = endDay;
	this.endDayOfWeek = endDayOfWeek;
	this.endTime = endTime;
	this.endTimeMode = endTimeMode;
	this.dstSavings = dstSavings;

	// this.useDaylight is set by decodeRules
	decodeRules();
	if (dstSavings <= 0) {
	throw new IllegalArgumentException("Illegal daylight saving value: " + dstSavings);
	}
	}

	/**
	* Sets the daylight saving time starting year.
	*
	* @param year The daylight saving starting year.
	*/
	public void setStartYear(int year)
	{
	startYear = year;
	invalidateCache();
	}

	/**
	* Sets the daylight saving time start rule. For example, if daylight saving
	* time starts on the first Sunday in April at 2 am in local wall clock
	* time, you can set the start rule by calling:
	* <pre><code>setStartRule(Calendar.APRIL, 1, Calendar.SUNDAY, 26060*1000);</code></pre>
	*
	* @param startMonth The daylight saving time starting month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 0 for January).
	* @param startDay The day of the month on which the daylight saving time starts.
	* See the class description for the special cases of this parameter.
	* @param startDayOfWeek The daylight saving time starting day-of-week.
	* See the class description for the special cases of this parameter.
	* @param startTime The daylight saving time starting time in local wall clock
	* time, which is local standard time in this case.
	* @exception IllegalArgumentException if the <code>startMonth</code>, <code>startDay</code>,
	* <code>startDayOfWeek</code>, or <code>startTime</code> parameters are out of range
	*/
	public void setStartRule(int startMonth, int startDay, int startDayOfWeek, int startTime)
	{
	this.startMonth = startMonth;
	this.startDay = startDay;
	this.startDayOfWeek = startDayOfWeek;
	this.startTime = startTime;
	startTimeMode = WALL_TIME;
	decodeStartRule();
	invalidateCache();
	}

	/**
	* Sets the daylight saving time start rule to a fixed date within a month.
	* This method is equivalent to:
	* <pre><code>setStartRule(startMonth, startDay, 0, startTime)</code></pre>
	*
	* @param startMonth The daylight saving time starting month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 0 for January).
	* @param startDay The day of the month on which the daylight saving time starts.
	* @param startTime The daylight saving time starting time in local wall clock
	* time, which is local standard time in this case.
	* See the class description for the special cases of this parameter.
	* @exception IllegalArgumentException if the <code>startMonth</code>,
	* <code>startDayOfMonth</code>, or <code>startTime</code> parameters are out of range
	* @since 1.2
	*/
	public void setStartRule(int startMonth, int startDay, int startTime) {
	setStartRule(startMonth, startDay, 0, startTime);
	}

	/**
	* Sets the daylight saving time start rule to a weekday before or after the given date within
	* a month, e.g., the first Monday on or after the 8th.
	*
	* @param startMonth The daylight saving time starting month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 0 for January).
	* @param startDay The day of the month on which the daylight saving time starts.
	* @param startDayOfWeek The daylight saving time starting day-of-week.
	* @param startTime The daylight saving time starting time in local wall clock
	* time, which is local standard time in this case.
	* @param after If true, this rule selects the first <code>dayOfWeek</code> on or
	* <em>after</em> <code>dayOfMonth</code>. If false, this rule
	* selects the last <code>dayOfWeek</code> on or <em>before</em>
	* <code>dayOfMonth</code>.
	* @exception IllegalArgumentException if the <code>startMonth</code>, <code>startDay</code>,
	* <code>startDayOfWeek</code>, or <code>startTime</code> parameters are out of range
	* @since 1.2
	*/
	public void setStartRule(int startMonth, int startDay, int startDayOfWeek,
	int startTime, boolean after)
	{
	// TODO: this method doesn't check the initial values of dayOfMonth or dayOfWeek.
	if (after) {
	setStartRule(startMonth, startDay, -startDayOfWeek, startTime);
	} else {
	setStartRule(startMonth, -startDay, -startDayOfWeek, startTime);
	}
	}

	/**
	* Sets the daylight saving time end rule. For example, if daylight saving time
	* ends on the last Sunday in October at 2 am in wall clock time,
	* you can set the end rule by calling:
	* <code>setEndRule(Calendar.OCTOBER, -1, Calendar.SUNDAY, 26060*1000);</code>
	*
	* @param endMonth The daylight saving time ending month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 9 for October).
	* @param endDay The day of the month on which the daylight saving time ends.
	* See the class description for the special cases of this parameter.
	* @param endDayOfWeek The daylight saving time ending day-of-week.
	* See the class description for the special cases of this parameter.
	* @param endTime The daylight saving ending time in local wall clock time,
	* (in milliseconds within the day) which is local daylight
	* time in this case.
	* @exception IllegalArgumentException if the <code>endMonth</code>, <code>endDay</code>,
	* <code>endDayOfWeek</code>, or <code>endTime</code> parameters are out of range
	*/
	public void setEndRule(int endMonth, int endDay, int endDayOfWeek,
	int endTime)
	{
	this.endMonth = endMonth;
	this.endDay = endDay;
	this.endDayOfWeek = endDayOfWeek;
	this.endTime = endTime;
	this.endTimeMode = WALL_TIME;
	decodeEndRule();
	invalidateCache();
	}

	/**
	* Sets the daylight saving time end rule to a fixed date within a month.
	* This method is equivalent to:
	* <pre><code>setEndRule(endMonth, endDay, 0, endTime)</code></pre>
	*
	* @param endMonth The daylight saving time ending month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 9 for October).
	* @param endDay The day of the month on which the daylight saving time ends.
	* @param endTime The daylight saving ending time in local wall clock time,
	* (in milliseconds within the day) which is local daylight
	* time in this case.
	* @exception IllegalArgumentException the <code>endMonth</code>, <code>endDay</code>,
	* or <code>endTime</code> parameters are out of range
	* @since 1.2
	*/
	public void setEndRule(int endMonth, int endDay, int endTime)
	{
	setEndRule(endMonth, endDay, 0, endTime);
	}

	/**
	* Sets the daylight saving time end rule to a weekday before or after the given date within
	* a month, e.g., the first Monday on or after the 8th.
	*
	* @param endMonth The daylight saving time ending month. Month is
	* a {@link Calendar#MONTH MONTH} field
	* value (0-based. e.g., 9 for October).
	* @param endDay The day of the month on which the daylight saving time ends.
	* @param endDayOfWeek The daylight saving time ending day-of-week.
	* @param endTime The daylight saving ending time in local wall clock time,
	* (in milliseconds within the day) which is local daylight
	* time in this case.
	* @param after If true, this rule selects the first <code>endDayOfWeek</code> on
	* or <em>after</em> <code>endDay</code>. If false, this rule
	* selects the last <code>endDayOfWeek</code> on or before
	* <code>endDay</code> of the month.
	* @exception IllegalArgumentException the <code>endMonth</code>, <code>endDay</code>,
	* <code>endDayOfWeek</code>, or <code>endTime</code> parameters are out of range
	* @since 1.2
	*/
	public void setEndRule(int endMonth, int endDay, int endDayOfWeek, int endTime, boolean after)
	{
	if (after) {
	setEndRule(endMonth, endDay, -endDayOfWeek, endTime);
	} else {
	setEndRule(endMonth, -endDay, -endDayOfWeek, endTime);
	}
	}

	/**
	* Returns the offset of this time zone from UTC at the given
	* time. If daylight saving time is in effect at the given time,
	* the offset value is adjusted with the amount of daylight
	* saving.
	*
	* @param date the time at which the time zone offset is found
	* @return the amount of time in milliseconds to add to UTC to get
	* local time.
	* @since 1.4
	*/
	public int getOffset(long date) {
	return getOffsets(date, null);
	}

	/**
	* @see TimeZone#getOffsets
	*/
	int getOffsets(long date, int[] offsets) {
	int offset = rawOffset;

	computeOffset:
	if (useDaylight) {
	Cache cache = this.cache;
	if (cache != null) {
	if (date >= cache.start && date < cache.end) {
	offset += dstSavings;
	break computeOffset;
	}
	}
	BaseCalendar cal = date >= GregorianCalendar.DEFAULT_GREGORIAN_CUTOVER ?
	gcal : (BaseCalendar) CalendarSystem.forName("julian");
	BaseCalendar.Date cdate = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.NO_TIMEZONE);
	// Get the year in local time
	cal.getCalendarDate(date + rawOffset, cdate);
	int year = cdate.getNormalizedYear();
	if (year >= startYear) {
	// Clear time elements for the transition calculations
	cdate.setTimeOfDay(0, 0, 0, 0);
	offset = getOffset(cal, cdate, year, date);
	}
	}

	if (offsets != null) {
	offsets[0] = rawOffset;
	offsets[1] = offset - rawOffset;
	}
	return offset;
	}

	/**
	* Returns the difference in milliseconds between local time and
	* UTC, taking into account both the raw offset and the effect of
	* daylight saving, for the specified date and time. This method
	* assumes that the start and end month are distinct. It also
	* uses a default {@link GregorianCalendar} object as its
	* underlying calendar, such as for determining leap years. Do
	* not use the result of this method with a calendar other than a
	* default <code>GregorianCalendar</code>.
	*
	* <p><em>Note: In general, clients should use
	* <code>Calendar.get(ZONE_OFFSET) + Calendar.get(DST_OFFSET)</code>
	* instead of calling this method.</em>
	*
	* @param era The era of the given date.
	* @param year The year in the given date.
	* @param month The month in the given date. Month is 0-based. e.g.,
	* 0 for January.
	* @param day The day-in-month of the given date.
	* @param dayOfWeek The day-of-week of the given date.
	* @param millis The milliseconds in day in <em>standard</em> local time.
	* @return The milliseconds to add to UTC to get local time.
	* @exception IllegalArgumentException the <code>era</code>,
	* <code>month</code>, <code>day</code>, <code>dayOfWeek</code>,
	* or <code>millis</code> parameters are out of range
	*/
	public int getOffset(int era, int year, int month, int day, int dayOfWeek,
	int millis)
	{
	if (era != GregorianCalendar.AD && era != GregorianCalendar.BC) {
	throw new IllegalArgumentException("Illegal era " + era);
	}

	int y = year;
	if (era == GregorianCalendar.BC) {
	// adjust y with the GregorianCalendar-style year numbering.
	y = 1 - y;
	}

	// If the year isn't representable with the 64-bit long
	// integer in milliseconds, convert the year to an
	// equivalent year. This is required to pass some JCK test cases
	// which are actually useless though because the specified years
	// can't be supported by the Java time system.
	if (y >= 292278994) {
	y = 2800 + y % 2800;
	} else if (y <= -292269054) {
	// y %= 28 also produces an equivalent year, but positive
	// year numbers would be convenient to use the UNIX cal
	// command.
	y = (int) CalendarUtils.mod((long) y, 28);
	}

	// convert year to its 1-based month value
	int m = month + 1;

	// First, calculate time as a Gregorian date.
	BaseCalendar cal = gcal;
	BaseCalendar.Date cdate = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.NO_TIMEZONE);
	cdate.setDate(y, m, day);
	long time = cal.getTime(cdate); // normalize cdate
	time += millis - rawOffset; // UTC time

	// If the time value represents a time before the default
	// Gregorian cutover, recalculate time using the Julian
	// calendar system. For the Julian calendar system, the
	// normalized year numbering is ..., -2 (BCE 2), -1 (BCE 1),
	// 1, 2 ... which is different from the GregorianCalendar
	// style year numbering (..., -1, 0 (BCE 1), 1, 2, ...).
	if (time < GregorianCalendar.DEFAULT_GREGORIAN_CUTOVER) {
	cal = (BaseCalendar) CalendarSystem.forName("julian");
	cdate = (BaseCalendar.Date) cal.newCalendarDate(TimeZone.NO_TIMEZONE);
	cdate.setNormalizedDate(y, m, day);
	time = cal.getTime(cdate) + millis - rawOffset;
	}

	if ((cdate.getNormalizedYear() != y)
	\|\| (cdate.getMonth() != m)
	\|\| (cdate.getDayOfMonth() != day)
	// The validation should be cdate.getDayOfWeek() ==
	// dayOfWeek. However, we don't check dayOfWeek for
	// compatibility.
	\|\| (dayOfWeek < Calendar.SUNDAY \|\| dayOfWeek > Calendar.SATURDAY)
	\|\| (millis < 0 \|\| millis >= (246060*1000))) {
	throw new IllegalArgumentException();
	}

	if (!useDaylight \|\| year < startYear \|\| era != GregorianCalendar.CE) {
	return rawOffset;
	}

	return getOffset(cal, cdate, y, time);
	}

	private int getOffset(BaseCalendar cal, BaseCalendar.Date cdate, int year, long time) {
	Cache cache = this.cache;
	if (cache != null) {
	if (time >= cache.start && time < cache.end) {
	return rawOffset + dstSavings;
	}
	if (year == cache.year) {
	return rawOffset;
	}
	}

	long start = getStart(cal, cdate, year);
	long end = getEnd(cal, cdate, year);
	int offset = rawOffset;
	if (start <= end) {
	if (time >= start && time < end) {
	offset += dstSavings;
	}
	this.cache = new Cache(year, start, end);
	} else {
	if (time < end) {
	// TODO: support Gregorian cutover. The previous year
	// may be in the other calendar system.
	start = getStart(cal, cdate, year - 1);
	if (time >= start) {
	offset += dstSavings;
	}
	} else if (time >= start) {
	// TODO: support Gregorian cutover. The next year
	// may be in the other calendar system.
	end = getEnd(cal, cdate, year + 1);
	if (time < end) {
	offset += dstSavings;
	}
	}
	if (start <= end) {
	this.cache = new Cache((long) startYear - 1, start, end);
	}
	}
	return offset;
	}

	private long getStart(BaseCalendar cal, BaseCalendar.Date cdate, int year) {
	int time = startTime;
	if (startTimeMode != UTC_TIME) {
	time -= rawOffset;
	}
	return getTransition(cal, cdate, startMode, year, startMonth, startDay,
	startDayOfWeek, time);
	}

	private long getEnd(BaseCalendar cal, BaseCalendar.Date cdate, int year) {
	int time = endTime;
	if (endTimeMode != UTC_TIME) {
	time -= rawOffset;
	}
	if (endTimeMode == WALL_TIME) {
	time -= dstSavings;
	}
	return getTransition(cal, cdate, endMode, year, endMonth, endDay,
	endDayOfWeek, time);
	}

	private long getTransition(BaseCalendar cal, BaseCalendar.Date cdate,
	int mode, int year, int month, int dayOfMonth,
	int dayOfWeek, int timeOfDay) {
	cdate.setNormalizedYear(year);
	cdate.setMonth(month + 1);
	switch (mode) {
	case DOM_MODE:
	cdate.setDayOfMonth(dayOfMonth);
	break;

	case DOW_IN_MONTH_MODE:
	cdate.setDayOfMonth(1);
	if (dayOfMonth < 0) {
	cdate.setDayOfMonth(cal.getMonthLength(cdate));
	}
	cdate = (BaseCalendar.Date) cal.getNthDayOfWeek(dayOfMonth, dayOfWeek, cdate);
	break;

	case DOW_GE_DOM_MODE:
	cdate.setDayOfMonth(dayOfMonth);
	cdate = (BaseCalendar.Date) cal.getNthDayOfWeek(1, dayOfWeek, cdate);
	break;

	case DOW_LE_DOM_MODE:
	cdate.setDayOfMonth(dayOfMonth);
	cdate = (BaseCalendar.Date) cal.getNthDayOfWeek(-1, dayOfWeek, cdate);
	break;
	}
	return cal.getTime(cdate) + timeOfDay;
	}

	/**
	* Gets the GMT offset for this time zone.
	* @return the GMT offset value in milliseconds
	* @see #setRawOffset
	*/
	public int getRawOffset()
	{
	// The given date will be taken into account while
	// we have the historical time zone data in place.
	return rawOffset;
	}

	/**
	* Sets the base time zone offset to GMT.
	* This is the offset to add to UTC to get local time.
	* @see #getRawOffset
	*/
	public void setRawOffset(int offsetMillis)
	{
	this.rawOffset = offsetMillis;
	}

	/**
	* Sets the amount of time in milliseconds that the clock is advanced
	* during daylight saving time.
	* @param millisSavedDuringDST the number of milliseconds the time is
	* advanced with respect to standard time when the daylight saving time rules
	* are in effect. A positive number, typically one hour (3600000).
	* @see #getDSTSavings
	* @since 1.2
	*/
	public void setDSTSavings(int millisSavedDuringDST) {
	if (millisSavedDuringDST <= 0) {
	throw new IllegalArgumentException("Illegal daylight saving value: "
	+ millisSavedDuringDST);
	}
	dstSavings = millisSavedDuringDST;
	}

	/**
	* Returns the amount of time in milliseconds that the clock is
	* advanced during daylight saving time.
	*
	* @return the number of milliseconds the time is advanced with
	* respect to standard time when the daylight saving rules are in
	* effect, or 0 (zero) if this time zone doesn't observe daylight
	* saving time.
	*
	* @see #setDSTSavings
	* @since 1.2
	*/
	public int getDSTSavings() {
	return useDaylight ? dstSavings : 0;
	}

	/**
	* Queries if this time zone uses daylight saving time.
	* @return true if this time zone uses daylight saving time;
	* false otherwise.
	*/
	public boolean useDaylightTime()
	{
	return useDaylight;
	}

	/**
	* Returns {@code true} if this {@code SimpleTimeZone} observes
	* Daylight Saving Time. This method is equivalent to {@link
	* #useDaylightTime()}.
	*
	* @return {@code true} if this {@code SimpleTimeZone} observes
	* Daylight Saving Time; {@code false} otherwise.
	* @since 1.7
	*/
	@Override
	public boolean observesDaylightTime() {
	return useDaylightTime();
	}

	/**
	* Queries if the given date is in daylight saving time.
	* @return true if daylight saving time is in effective at the
	* given date; false otherwise.
	*/
	public boolean inDaylightTime(Date date)
	{
	return (getOffset(date.getTime()) != rawOffset);
	}

	/**
	* Returns a clone of this <code>SimpleTimeZone</code> instance.
	* @return a clone of this instance.
	*/
	public Object clone()
	{
	return super.clone();
	}

	/**
	* Generates the hash code for the SimpleDateFormat object.
	* @return the hash code for this object
	*/
	public int hashCode()
	{
	return startMonth ^ startDay ^ startDayOfWeek ^ startTime ^
	endMonth ^ endDay ^ endDayOfWeek ^ endTime ^ rawOffset;
	}

	/**
	* Compares the equality of two <code>SimpleTimeZone</code> objects.
	*
	* @param obj The <code>SimpleTimeZone</code> object to be compared with.
	* @return True if the given <code>obj</code> is the same as this
	* <code>SimpleTimeZone</code> object; false otherwise.
	*/
	public boolean equals(Object obj)
	{
	if (this == obj) {
	return true;
	}
	if (!(obj instanceof SimpleTimeZone)) {
	return false;
	}

	SimpleTimeZone that = (SimpleTimeZone) obj;

	return getID().equals(that.getID()) &&
	hasSameRules(that);
	}

	/**
	* Returns <code>true</code> if this zone has the same rules and offset as another zone.
	* @param other the TimeZone object to be compared with
	* @return <code>true</code> if the given zone is a SimpleTimeZone and has the
	* same rules and offset as this one
	* @since 1.2
	*/
	public boolean hasSameRules(TimeZone other) {
	if (this == other) {
	return true;
	}
	if (!(other instanceof SimpleTimeZone)) {
	return false;
	}
	SimpleTimeZone that = (SimpleTimeZone) other;
	return rawOffset == that.rawOffset &&
	useDaylight == that.useDaylight &&
	(!useDaylight
	// Only check rules if using DST
	\|\| (dstSavings == that.dstSavings &&
	startMode == that.startMode &&
	startMonth == that.startMonth &&
	startDay == that.startDay &&
	startDayOfWeek == that.startDayOfWeek &&
	startTime == that.startTime &&
	startTimeMode == that.startTimeMode &&
	endMode == that.endMode &&
	endMonth == that.endMonth &&
	endDay == that.endDay &&
	endDayOfWeek == that.endDayOfWeek &&
	endTime == that.endTime &&
	endTimeMode == that.endTimeMode &&
	startYear == that.startYear));
	}

	/**
	* Returns a string representation of this time zone.
	* @return a string representation of this time zone.
	*/
	public String toString() {
	return getClass().getName() +
	"[id=" + getID() +
	",offset=" + rawOffset +
	",dstSavings=" + dstSavings +
	",useDaylight=" + useDaylight +
	",startYear=" + startYear +
	",startMode=" + startMode +
	",startMonth=" + startMonth +
	",startDay=" + startDay +
	",startDayOfWeek=" + startDayOfWeek +
	",startTime=" + startTime +
	",startTimeMode=" + startTimeMode +
	",endMode=" + endMode +
	",endMonth=" + endMonth +
	",endDay=" + endDay +
	",endDayOfWeek=" + endDayOfWeek +
	",endTime=" + endTime +
	",endTimeMode=" + endTimeMode + ']';
	}

	// =======================privates===============================

	/**
	* The month in which daylight saving time starts. This value must be
	* between <code>Calendar.JANUARY</code> and
	* <code>Calendar.DECEMBER</code> inclusive. This value must not equal
	* <code>endMonth</code>.
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	*/
	private int startMonth;

	/**
	* This field has two possible interpretations:
	* <dl>
	* <dt><code>startMode == DOW_IN_MONTH</code></dt>
	* <dd>
	* <code>startDay</code> indicates the day of the month of
	* <code>startMonth</code> on which daylight
	* saving time starts, from 1 to 28, 30, or 31, depending on the
	* <code>startMonth</code>.
	* </dd>
	* <dt><code>startMode != DOW_IN_MONTH</code></dt>
	* <dd>
	* <code>startDay</code> indicates which <code>startDayOfWeek</code> in the
	* month <code>startMonth</code> daylight
	* saving time starts on. For example, a value of +1 and a
	* <code>startDayOfWeek</code> of <code>Calendar.SUNDAY</code> indicates the
	* first Sunday of <code>startMonth</code>. Likewise, +2 would indicate the
	* second Sunday, and -1 the last Sunday. A value of 0 is illegal.
	* </dd>
	* </dl>
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	*/
	private int startDay;

	/**
	* The day of the week on which daylight saving time starts. This value
	* must be between <code>Calendar.SUNDAY</code> and
	* <code>Calendar.SATURDAY</code> inclusive.
	* <p>If <code>useDaylight</code> is false or
	* <code>startMode == DAY_OF_MONTH</code>, this value is ignored.
	* @serial
	*/
	private int startDayOfWeek;

	/**
	* The time in milliseconds after midnight at which daylight saving
	* time starts. This value is expressed as wall time, standard time,
	* or UTC time, depending on the setting of <code>startTimeMode</code>.
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	*/
	private int startTime;

	/**
	* The format of startTime, either WALL_TIME, STANDARD_TIME, or UTC_TIME.
	* @serial
	* @since 1.3
	*/
	private int startTimeMode;

	/**
	* The month in which daylight saving time ends. This value must be
	* between <code>Calendar.JANUARY</code> and
	* <code>Calendar.UNDECIMBER</code>. This value must not equal
	* <code>startMonth</code>.
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	*/
	private int endMonth;

	/**
	* This field has two possible interpretations:
	* <dl>
	* <dt><code>endMode == DOW_IN_MONTH</code></dt>
	* <dd>
	* <code>endDay</code> indicates the day of the month of
	* <code>endMonth</code> on which daylight
	* saving time ends, from 1 to 28, 30, or 31, depending on the
	* <code>endMonth</code>.
	* </dd>
	* <dt><code>endMode != DOW_IN_MONTH</code></dt>
	* <dd>
	* <code>endDay</code> indicates which <code>endDayOfWeek</code> in th
	* month <code>endMonth</code> daylight
	* saving time ends on. For example, a value of +1 and a
	* <code>endDayOfWeek</code> of <code>Calendar.SUNDAY</code> indicates the
	* first Sunday of <code>endMonth</code>. Likewise, +2 would indicate the
	* second Sunday, and -1 the last Sunday. A value of 0 is illegal.
	* </dd>
	* </dl>
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	*/
	private int endDay;

	/**
	* The day of the week on which daylight saving time ends. This value
	* must be between <code>Calendar.SUNDAY</code> and
	* <code>Calendar.SATURDAY</code> inclusive.
	* <p>If <code>useDaylight</code> is false or
	* <code>endMode == DAY_OF_MONTH</code>, this value is ignored.
	* @serial
	*/
	private int endDayOfWeek;

	/**
	* The time in milliseconds after midnight at which daylight saving
	* time ends. This value is expressed as wall time, standard time,
	* or UTC time, depending on the setting of <code>endTimeMode</code>.
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	*/
	private int endTime;

	/**
	* The format of endTime, either <code>WALL_TIME</code>,
	* <code>STANDARD_TIME</code>, or <code>UTC_TIME</code>.
	* @serial
	* @since 1.3
	*/
	private int endTimeMode;

	/**
	* The year in which daylight saving time is first observed. This is an {@link GregorianCalendar#AD AD}
	* value. If this value is less than 1 then daylight saving time is observed
	* for all <code>AD</code> years.
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	*/
	private int startYear;

	/**
	* The offset in milliseconds between this zone and GMT. Negative offsets
	* are to the west of Greenwich. To obtain local <em>standard</em> time,
	* add the offset to GMT time. To obtain local wall time it may also be
	* necessary to add <code>dstSavings</code>.
	* @serial
	*/
	private int rawOffset;

	/**
	* A boolean value which is true if and only if this zone uses daylight
	* saving time. If this value is false, several other fields are ignored.
	* @serial
	*/
	private boolean useDaylight=false; // indicate if this time zone uses DST

	private static final int millisPerHour = 60601000;
	private static final int millisPerDay = 24*millisPerHour;

	/**
	* This field was serialized in JDK 1.1, so we have to keep it that way
	* to maintain serialization compatibility. However, there's no need to
	* recreate the array each time we create a new time zone.
	* @serial An array of bytes containing the values {31, 28, 31, 30, 31, 30,
	* 31, 31, 30, 31, 30, 31}. This is ignored as of the Java 2 platform v1.2, however, it must
	* be streamed out for compatibility with JDK 1.1.
	*/
	private final byte monthLength[] = staticMonthLength;
	private static final byte staticMonthLength[] = {31,28,31,30,31,30,31,31,30,31,30,31};
	private static final byte staticLeapMonthLength[] = {31,29,31,30,31,30,31,31,30,31,30,31};

	/**
	* Variables specifying the mode of the start rule. Takes the following
	* values:
	* <dl>
	* <dt><code>DOM_MODE</code></dt>
	* <dd>
	* Exact day of week; e.g., March 1.
	* </dd>
	* <dt><code>DOW_IN_MONTH_MODE</code></dt>
	* <dd>
	* Day of week in month; e.g., last Sunday in March.
	* </dd>
	* <dt><code>DOW_GE_DOM_MODE</code></dt>
	* <dd>
	* Day of week after day of month; e.g., Sunday on or after March 15.
	* </dd>
	* <dt><code>DOW_LE_DOM_MODE</code></dt>
	* <dd>
	* Day of week before day of month; e.g., Sunday on or before March 15.
	* </dd>
	* </dl>
	* The setting of this field affects the interpretation of the
	* <code>startDay</code> field.
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	* @since 1.1.4
	*/
	private int startMode;

	/**
	* Variables specifying the mode of the end rule. Takes the following
	* values:
	* <dl>
	* <dt><code>DOM_MODE</code></dt>
	* <dd>
	* Exact day of week; e.g., March 1.
	* </dd>
	* <dt><code>DOW_IN_MONTH_MODE</code></dt>
	* <dd>
	* Day of week in month; e.g., last Sunday in March.
	* </dd>
	* <dt><code>DOW_GE_DOM_MODE</code></dt>
	* <dd>
	* Day of week after day of month; e.g., Sunday on or after March 15.
	* </dd>
	* <dt><code>DOW_LE_DOM_MODE</code></dt>
	* <dd>
	* Day of week before day of month; e.g., Sunday on or before March 15.
	* </dd>
	* </dl>
	* The setting of this field affects the interpretation of the
	* <code>endDay</code> field.
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	* @since 1.1.4
	*/
	private int endMode;

	/**
	* A positive value indicating the amount of time saved during DST in
	* milliseconds.
	* Typically one hour (3600000); sometimes 30 minutes (1800000).
	* <p>If <code>useDaylight</code> is false, this value is ignored.
	* @serial
	* @since 1.1.4
	*/
	private int dstSavings;

	private static final Gregorian gcal = CalendarSystem.getGregorianCalendar();

	/**
	* Cache values representing a single period of daylight saving
	* time. Cache.start is the start time (inclusive) of daylight
	* saving time and Cache.end is the end time (exclusive).
	*
	* Cache.year has a year value if both Cache.start and Cache.end are
	* in the same year. Cache.year is set to startYear - 1 if
	* Cache.start and Cache.end are in different years.
	* Cache.year is a long to support Integer.MIN_VALUE - 1 (JCK requirement).
	*/
	private static final class Cache {
	final long year;
	final long start;
	final long end;

	Cache(long year, long start, long end) {
	this.year = year;
	this.start = start;
	this.end = end;
	}
	}

	private transient volatile Cache cache;

	/**
	* Constants specifying values of startMode and endMode.
	*/
	private static final int DOM_MODE = 1; // Exact day of month, "Mar 1"
	private static final int DOW_IN_MONTH_MODE = 2; // Day of week in month, "lastSun"
	private static final int DOW_GE_DOM_MODE = 3; // Day of week after day of month, "Sun>=15"
	private static final int DOW_LE_DOM_MODE = 4; // Day of week before day of month, "Sun<=21"

	/**
	* Constant for a mode of start or end time specified as wall clock
	* time. Wall clock time is standard time for the onset rule, and
	* daylight time for the end rule.
	* @since 1.4
	*/
	public static final int WALL_TIME = 0; // Zero for backward compatibility

	/**
	* Constant for a mode of start or end time specified as standard time.
	* @since 1.4
	*/
	public static final int STANDARD_TIME = 1;

	/**
	* Constant for a mode of start or end time specified as UTC. European
	* Union rules are specified as UTC time, for example.
	* @since 1.4
	*/
	public static final int UTC_TIME = 2;

	// Proclaim compatibility with 1.1
	static final long serialVersionUID = -403250971215465050L;

	// the internal serial version which says which version was written
	// - 0 (default) for version up to JDK 1.1.3
	// - 1 for version from JDK 1.1.4, which includes 3 new fields
	// - 2 for JDK 1.3, which includes 2 new fields
	static final int currentSerialVersion = 2;

	/**
	* The version of the serialized data on the stream. Possible values:
	* <dl>
	* <dt><b>0</b> or not present on stream</dt>
	* <dd>
	* JDK 1.1.3 or earlier.
	* </dd>
	* <dt><b>1</b></dt>
	* <dd>
	* JDK 1.1.4 or later. Includes three new fields: <code>startMode</code>,
	* <code>endMode</code>, and <code>dstSavings</code>.
	* </dd>
	* <dt><b>2</b></dt>
	* <dd>
	* JDK 1.3 or later. Includes two new fields: <code>startTimeMode</code>
	* and <code>endTimeMode</code>.
	* </dd>
	* </dl>
	* When streaming out this class, the most recent format
	* and the highest allowable <code>serialVersionOnStream</code>
	* is written.
	* @serial
	* @since 1.1.4
	*/
	private int serialVersionOnStream = currentSerialVersion;

	// Maximum number of rules.
	private static final int MAX_RULE_NUM = 6;

	private void invalidateCache() {
	cache = null;
	}

	//----------------------------------------------------------------------
	// Rule representation
	//
	// We represent the following flavors of rules:
	// 5 the fifth of the month
	// lastSun the last Sunday in the month
	// lastMon the last Monday in the month
	// Sun>=8 first Sunday on or after the eighth
	// Sun<=25 last Sunday on or before the 25th
	// This is further complicated by the fact that we need to remain
	// backward compatible with the 1.1 FCS. Finally, we need to minimize
	// API changes. In order to satisfy these requirements, we support
	// three representation systems, and we translate between them.
	//
	// INTERNAL REPRESENTATION
	// This is the format SimpleTimeZone objects take after construction or
	// streaming in is complete. Rules are represented directly, using an
	// unencoded format. We will discuss the start rule only below; the end
	// rule is analogous.
	// startMode Takes on enumerated values DAY_OF_MONTH,
	// DOW_IN_MONTH, DOW_AFTER_DOM, or DOW_BEFORE_DOM.
	// startDay The day of the month, or for DOW_IN_MONTH mode, a
	// value indicating which DOW, such as +1 for first,
	// +2 for second, -1 for last, etc.
	// startDayOfWeek The day of the week. Ignored for DAY_OF_MONTH.
	//
	// ENCODED REPRESENTATION
	// This is the format accepted by the constructor and by setStartRule()
	// and setEndRule(). It uses various combinations of positive, negative,
	// and zero values to encode the different rules. This representation
	// allows us to specify all the different rule flavors without altering
	// the API.
	// MODE startMonth startDay startDayOfWeek
	// DOW_IN_MONTH_MODE >=0 !=0 >0
	// DOM_MODE >=0 >0 ==0
	// DOW_GE_DOM_MODE >=0 >0 <0
	// DOW_LE_DOM_MODE >=0 <0 <0
	// (no DST) don't care ==0 don't care
	//
	// STREAMED REPRESENTATION
	// We must retain binary compatibility with the 1.1 FCS. The 1.1 code only
	// handles DOW_IN_MONTH_MODE and non-DST mode, the latter indicated by the
	// flag useDaylight. When we stream an object out, we translate into an
	// approximate DOW_IN_MONTH_MODE representation so the object can be parsed
	// and used by 1.1 code. Following that, we write out the full
	// representation separately so that contemporary code can recognize and
	// parse it. The full representation is written in a "packed" format,
	// consisting of a version number, a length, and an array of bytes. Future
	// versions of this class may specify different versions. If they wish to
	// include additional data, they should do so by storing them after the
	// packed representation below.
	//----------------------------------------------------------------------

	/**
	* Given a set of encoded rules in startDay and startDayOfMonth, decode
	* them and set the startMode appropriately. Do the same for endDay and
	* endDayOfMonth. Upon entry, the day of week variables may be zero or
	* negative, in order to indicate special modes. The day of month
	* variables may also be negative. Upon exit, the mode variables will be
	* set, and the day of week and day of month variables will be positive.
	* This method also recognizes a startDay or endDay of zero as indicating
	* no DST.
	*/
	private void decodeRules()
	{
	decodeStartRule();
	decodeEndRule();
	}

	/**
	* Decode the start rule and validate the parameters. The parameters are
	* expected to be in encoded form, which represents the various rule modes
	* by negating or zeroing certain values. Representation formats are:
	* <p>
	* <pre>
	* DOW_IN_MONTH DOM DOW>=DOM DOW<=DOM no DST
	* ------------ ----- -------- -------- ----------
	* month 0..11 same same same don't care
	* day -5..5 1..31 1..31 -1..-31 0
	* dayOfWeek 1..7 0 -1..-7 -1..-7 don't care
	* time 0..ONEDAY same same same don't care
	* </pre>
	* The range for month does not include UNDECIMBER since this class is
	* really specific to GregorianCalendar, which does not use that month.
	* The range for time includes ONEDAY (vs. ending at ONEDAY-1) because the
	* end rule is an exclusive limit point. That is, the range of times that
	* are in DST include those >= the start and < the end. For this reason,
	* it should be possible to specify an end of ONEDAY in order to include the
	* entire day. Although this is equivalent to time 0 of the following day,
	* it's not always possible to specify that, for example, on December 31.
	* While arguably the start range should still be 0..ONEDAY-1, we keep
	* the start and end ranges the same for consistency.
	*/
	private void decodeStartRule() {
	useDaylight = (startDay != 0) && (endDay != 0);
	if (startDay != 0) {
	if (startMonth < Calendar.JANUARY \|\| startMonth > Calendar.DECEMBER) {
	throw new IllegalArgumentException(
	"Illegal start month " + startMonth);
	}
	if (startTime < 0 \|\| startTime > millisPerDay) {
	throw new IllegalArgumentException(
	"Illegal start time " + startTime);
	}
	if (startDayOfWeek == 0) {
	startMode = DOM_MODE;
	} else {
	if (startDayOfWeek > 0) {
	startMode = DOW_IN_MONTH_MODE;
	} else {
	startDayOfWeek = -startDayOfWeek;
	if (startDay > 0) {
	startMode = DOW_GE_DOM_MODE;
	} else {
	startDay = -startDay;
	startMode = DOW_LE_DOM_MODE;
	}
	}
	if (startDayOfWeek > Calendar.SATURDAY) {
	throw new IllegalArgumentException(
	"Illegal start day of week " + startDayOfWeek);
	}
	}
	if (startMode == DOW_IN_MONTH_MODE) {
	if (startDay < -5 \|\| startDay > 5) {
	throw new IllegalArgumentException(
	"Illegal start day of week in month " + startDay);
	}
	} else if (startDay < 1 \|\| startDay > staticMonthLength[startMonth]) {
	throw new IllegalArgumentException(
	"Illegal start day " + startDay);
	}
	}
	}

	/**
	* Decode the end rule and validate the parameters. This method is exactly
	* analogous to decodeStartRule().
	* @see decodeStartRule
	*/
	private void decodeEndRule() {
	useDaylight = (startDay != 0) && (endDay != 0);
	if (endDay != 0) {
	if (endMonth < Calendar.JANUARY \|\| endMonth > Calendar.DECEMBER) {
	throw new IllegalArgumentException(
	"Illegal end month " + endMonth);
	}
	if (endTime < 0 \|\| endTime > millisPerDay) {
	throw new IllegalArgumentException(
	"Illegal end time " + endTime);
	}
	if (endDayOfWeek == 0) {
	endMode = DOM_MODE;
	} else {
	if (endDayOfWeek > 0) {
	endMode = DOW_IN_MONTH_MODE;
	} else {
	endDayOfWeek = -endDayOfWeek;
	if (endDay > 0) {
	endMode = DOW_GE_DOM_MODE;
	} else {
	endDay = -endDay;
	endMode = DOW_LE_DOM_MODE;
	}
	}
	if (endDayOfWeek > Calendar.SATURDAY) {
	throw new IllegalArgumentException(
	"Illegal end day of week " + endDayOfWeek);
	}
	}
	if (endMode == DOW_IN_MONTH_MODE) {
	if (endDay < -5 \|\| endDay > 5) {
	throw new IllegalArgumentException(
	"Illegal end day of week in month " + endDay);
	}
	} else if (endDay < 1 \|\| endDay > staticMonthLength[endMonth]) {
	throw new IllegalArgumentException(
	"Illegal end day " + endDay);
	}
	}
	}

	/**
	* Make rules compatible to 1.1 FCS code. Since 1.1 FCS code only understands
	* day-of-week-in-month rules, we must modify other modes of rules to their
	* approximate equivalent in 1.1 FCS terms. This method is used when streaming
	* out objects of this class. After it is called, the rules will be modified,
	* with a possible loss of information. startMode and endMode will NOT be
	* altered, even though semantically they should be set to DOW_IN_MONTH_MODE,
	* since the rule modification is only intended to be temporary.
	*/
	private void makeRulesCompatible()
	{
	switch (startMode) {
	case DOM_MODE:
	startDay = 1 + (startDay / 7);
	startDayOfWeek = Calendar.SUNDAY;
	break;

	case DOW_GE_DOM_MODE:
	// A day-of-month of 1 is equivalent to DOW_IN_MONTH_MODE
	// that is, Sun>=1 == firstSun.
	if (startDay != 1) {
	startDay = 1 + (startDay / 7);
	}
	break;

	case DOW_LE_DOM_MODE:
	if (startDay >= 30) {
	startDay = -1;
	} else {
	startDay = 1 + (startDay / 7);
	}
	break;
	}

	switch (endMode) {
	case DOM_MODE:
	endDay = 1 + (endDay / 7);
	endDayOfWeek = Calendar.SUNDAY;
	break;

	case DOW_GE_DOM_MODE:
	// A day-of-month of 1 is equivalent to DOW_IN_MONTH_MODE
	// that is, Sun>=1 == firstSun.
	if (endDay != 1) {
	endDay = 1 + (endDay / 7);
	}
	break;

	case DOW_LE_DOM_MODE:
	if (endDay >= 30) {
	endDay = -1;
	} else {
	endDay = 1 + (endDay / 7);
	}
	break;
	}

	/*
	* Adjust the start and end times to wall time. This works perfectly
	* well unless it pushes into the next or previous day. If that
	* happens, we attempt to adjust the day rule somewhat crudely. The day
	* rules have been forced into DOW_IN_MONTH mode already, so we change
	* the day of week to move forward or back by a day. It's possible to
	* make a more refined adjustment of the original rules first, but in
	* most cases this extra effort will go to waste once we adjust the day
	* rules anyway.
	*/
	switch (startTimeMode) {
	case UTC_TIME:
	startTime += rawOffset;
	break;
	}
	while (startTime < 0) {
	startTime += millisPerDay;
	startDayOfWeek = 1 + ((startDayOfWeek+5) % 7); // Back 1 day
	}
	while (startTime >= millisPerDay) {
	startTime -= millisPerDay;
	startDayOfWeek = 1 + (startDayOfWeek % 7); // Forward 1 day
	}

	switch (endTimeMode) {
	case UTC_TIME:
	endTime += rawOffset + dstSavings;
	break;
	case STANDARD_TIME:
	endTime += dstSavings;
	}
	while (endTime < 0) {
	endTime += millisPerDay;
	endDayOfWeek = 1 + ((endDayOfWeek+5) % 7); // Back 1 day
	}
	while (endTime >= millisPerDay) {
	endTime -= millisPerDay;
	endDayOfWeek = 1 + (endDayOfWeek % 7); // Forward 1 day
	}
	}

	/**
	* Pack the start and end rules into an array of bytes. Only pack
	* data which is not preserved by makeRulesCompatible.
	*/
	private byte[] packRules()
	{
	byte[] rules = new byte[MAX_RULE_NUM];
	rules[0] = (byte)startDay;
	rules[1] = (byte)startDayOfWeek;
	rules[2] = (byte)endDay;
	rules[3] = (byte)endDayOfWeek;

	// As of serial version 2, include time modes
	rules[4] = (byte)startTimeMode;
	rules[5] = (byte)endTimeMode;

	return rules;
	}

	/**
	* Given an array of bytes produced by packRules, interpret them
	* as the start and end rules.
	*/
	private void unpackRules(byte[] rules)
	{
	startDay = rules[0];
	startDayOfWeek = rules[1];
	endDay = rules[2];
	endDayOfWeek = rules[3];

	// As of serial version 2, include time modes
	if (rules.length >= MAX_RULE_NUM) {
	startTimeMode = rules[4];
	endTimeMode = rules[5];
	}
	}

	/**
	* Pack the start and end times into an array of bytes. This is required
	* as of serial version 2.
	*/
	private int[] packTimes() {
	int[] times = new int[2];
	times[0] = startTime;
	times[1] = endTime;
	return times;
	}

	/**
	* Unpack the start and end times from an array of bytes. This is required
	* as of serial version 2.
	*/
	private void unpackTimes(int[] times) {
	startTime = times[0];
	endTime = times[1];
	}

	/**
	* Save the state of this object to a stream (i.e., serialize it).
	*
	* @serialData We write out two formats, a JDK 1.1 compatible format, using
	* <code>DOW_IN_MONTH_MODE</code> rules, in the required section, followed
	* by the full rules, in packed format, in the optional section. The
	* optional section will be ignored by JDK 1.1 code upon stream in.
	* <p> Contents of the optional section: The length of a byte array is
	* emitted (int); this is 4 as of this release. The byte array of the given
	* length is emitted. The contents of the byte array are the true values of
	* the fields <code>startDay</code>, <code>startDayOfWeek</code>,
	* <code>endDay</code>, and <code>endDayOfWeek</code>. The values of these
	* fields in the required section are approximate values suited to the rule
	* mode <code>DOW_IN_MONTH_MODE</code>, which is the only mode recognized by
	* JDK 1.1.
	*/
	private void writeObject(ObjectOutputStream stream)
	throws IOException
	{
	// Construct a binary rule
	byte[] rules = packRules();
	int[] times = packTimes();

	// Convert to 1.1 FCS rules. This step may cause us to lose information.
	makeRulesCompatible();

	// Write out the 1.1 FCS rules
	stream.defaultWriteObject();

	// Write out the binary rules in the optional data area of the stream.
	stream.writeInt(rules.length);
	stream.write(rules);
	stream.writeObject(times);

	// Recover the original rules. This recovers the information lost
	// by makeRulesCompatible.
	unpackRules(rules);
	unpackTimes(times);
	}

	/**
	* Reconstitute this object from a stream (i.e., deserialize it).
	*
	* We handle both JDK 1.1
	* binary formats and full formats with a packed byte array.
	*/
	private void readObject(ObjectInputStream stream)
	throws IOException, ClassNotFoundException
	{
	stream.defaultReadObject();

	if (serialVersionOnStream < 1) {
	// Fix a bug in the 1.1 SimpleTimeZone code -- namely,
	// startDayOfWeek and endDayOfWeek were usually uninitialized. We can't do
	// too much, so we assume SUNDAY, which actually works most of the time.
	if (startDayOfWeek == 0) {
	startDayOfWeek = Calendar.SUNDAY;
	}
	if (endDayOfWeek == 0) {
	endDayOfWeek = Calendar.SUNDAY;
	}

	// The variables dstSavings, startMode, and endMode are post-1.1, so they
	// won't be present if we're reading from a 1.1 stream. Fix them up.
	startMode = endMode = DOW_IN_MONTH_MODE;
	dstSavings = millisPerHour;
	} else {
	// For 1.1.4, in addition to the 3 new instance variables, we also
	// store the actual rules (which have not be made compatible with 1.1)
	// in the optional area. Read them in here and parse them.
	int length = stream.readInt();
	if (length <= MAX_RULE_NUM) {
	byte[] rules = new byte[length];
	stream.readFully(rules);
	unpackRules(rules);
	} else {
	throw new InvalidObjectException("Too many rules: " + length);
	}
	}

	if (serialVersionOnStream >= 2) {
	int[] times = (int[]) stream.readObject();
	unpackTimes(times);
	}

	serialVersionOnStream = currentSerialVersion;
	}
	}

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