simpletimezone.java

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     * @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) {

	// Workaround fix for 4278609 (JCK failure)
	if (endMonth == Calendar.JANUARY && endDay == 1 &&
	    endDayOfWeek == 0 && endTime == 0 && endTimeMode == WALL_TIME &&
	    dstSavings > 0) {
	    endMonth = Calendar.DECEMBER;
	    endDay = 31;
	    endTime = (24 * 60 * 60 * 1000) - dstSavings;
	    endTimeMode = STANDARD_TIME;
	}

        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;
    }

    /**
     * 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, 2*60*60*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;
        // useDaylight = true; // Set by decodeRules
        decodeStartRule();
    }

    /**
     * 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 dsyOfWeek.
        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, 2*60*60*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;
        // useDaylight = true; // Set by decodeRules
        decodeEndRule();
    }

    /**
     * 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;

    calc:
	{
	    if (!useDaylight) {
		offset = rawOffset;
		break calc;
	    }

	    // get standard local time
	    CalendarDate cdate = Gregorian.getCalendarDate(date + rawOffset);

	    int year = cdate.getYear();
	    // if it's BC, assume no DST.
	    if (year <= 0) {
		offset = rawOffset;
		break calc;
	    }
	    int month = cdate.getMonth();
	    int monthLength = staticMonthLength[month];
	    int prevMonthLength = staticMonthLength[(month + Calendar.DECEMBER) % 12];
	    if (Gregorian.isLeapYear(year)) {
		if (month == Calendar.FEBRUARY) { 
		    ++monthLength;
		} else if (month == Calendar.MARCH) {
		    ++prevMonthLength;
		}
	    }
	    offset = getOffset(GregorianCalendar.AD, year, month, cdate.getDate(), 
			       cdate.getDayOfWeek(), cdate.getTimeOfDay(),
			       monthLength, prevMonthLength);
	}

	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)
    {
        // Check the month before indexing into staticMonthLength. This
	// duplicates the test that occurs in the 7-argument getOffset(),
	// however, this is unavoidable. We don't mind because this method, in
	// fact, should not be called; internal code should always call the