simpletimezone.java

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     * @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 synchronized 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 true if this zone has the same rules and offset as another zone.
     * @param other the TimeZone object to be compared with
     * @return true 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 th
     * 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>
     * </ul>
     * <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>
     * </ul>
     * <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 WALL_TIME, STANDARD_TIME, or UTC_TIME.
     * @serial
     * @since 1.3
     */
    private int endTimeMode;

    /**
     * The year in which daylight saving time is first observed.  This is an AD
     * value.  If this value is less than 1 then daylight saving time is observed
     * for all AD 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 = 60*60*1000;
    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 final static byte staticMonthLength[] = {31,28,31,30,31,30,31,31,30,31,30,31};
    private final static 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>