dateformat.java

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     * pattern character 'z'.
     * @return the formatted date/time string.
     */
    public abstract StringBuffer format(Date date, StringBuffer toAppendTo,
                                        FieldPosition fieldPosition);

    /**
     * Formats a Date into a date/time string.
     * @param date the time value to be formatted into a time string.
     * @return the formatted time string.
     */
    public final String format(Date date)
    {
        return format(date, new StringBuffer(),
		      DontCareFieldPosition.INSTANCE).toString();
    }

    /**
     * Parses text from the beginning of the given string to produce a date.
     * The method may not use the entire text of the given string.
     * <p>
     * See the {@link #parse(String, ParsePosition)} method for more information
     * on date parsing.
     *
     * @param source A <code>String</code> whose beginning should be parsed.
     * @return A <code>Date</code> parsed from the string.
     * @exception ParseException if the beginning of the specified string
     *            cannot be parsed.
     */
    public Date parse(String source) throws ParseException
    {
        ParsePosition pos = new ParsePosition(0);
        Date result = parse(source, pos);
        if (pos.index == 0)
            throw new ParseException("Unparseable date: \"" + source + "\"" ,
                pos.errorIndex);
        return result;
    }

    /**
     * Parse a date/time string according to the given parse position.  For
     * example, a time text "07/10/96 4:5 PM, PDT" will be parsed into a Date
     * that is equivalent to Date(837039928046).
     *
     * <p> By default, parsing is lenient: If the input is not in the form used
     * by this object's format method but can still be parsed as a date, then
     * the parse succeeds.  Clients may insist on strict adherence to the
     * format by calling setLenient(false).
     *
     * @see java.text.DateFormat#setLenient(boolean)
     *
     * @param source  The date/time string to be parsed
     *
     * @param pos   On input, the position at which to start parsing; on
     *              output, the position at which parsing terminated, or the
     *              start position if the parse failed.
     *
     * @return      A Date, or null if the input could not be parsed
     */
    public abstract Date parse(String source, ParsePosition pos);

    /**
     * Parses text from a string to produce a <code>Date</code>.
     * <p>
     * The method attempts to parse text starting at the index given by
     * <code>pos</code>.
     * If parsing succeeds, then the index of <code>pos</code> is updated
     * to the index after the last character used (parsing does not necessarily
     * use all characters up to the end of the string), and the parsed
     * date is returned. The updated <code>pos</code> can be used to
     * indicate the starting point for the next call to this method.
     * If an error occurs, then the index of <code>pos</code> is not
     * changed, the error index of <code>pos</code> is set to the index of
     * the character where the error occurred, and null is returned.
     * <p>
     * See the {@link #parse(String, ParsePosition)} method for more information
     * on date parsing.
     *
     * @param source A <code>String</code>, part of which should be parsed.
     * @param pos A <code>ParsePosition</code> object with index and error
     *            index information as described above.
     * @return A <code>Date</code> parsed from the string. In case of
     *         error, returns null.
     * @exception NullPointerException if <code>pos</code> is null.
     */
    public Object parseObject(String source, ParsePosition pos) {
        return parse(source, pos);
    }

    /**
     * Constant for full style pattern.
     */
    public static final int FULL = 0;
    /**
     * Constant for long style pattern.
     */
    public static final int LONG = 1;
    /**
     * Constant for medium style pattern.
     */
    public static final int MEDIUM = 2;
    /**
     * Constant for short style pattern.
     */
    public static final int SHORT = 3;
    /**
     * Constant for default style pattern.  Its value is MEDIUM.
     */
    public static final int DEFAULT = MEDIUM;

    /**
     * Gets the time formatter with the default formatting style
     * for the default locale.
     * @return a time formatter.
     */
    public final static DateFormat getTimeInstance()
    {
        return get(DEFAULT, 0, 1, Locale.getDefault());
    }

    /**
     * Gets the time formatter with the given formatting style
     * for the default locale.
     * @param style the given formatting style. For example,
     * SHORT for "h:mm a" in the US locale.
     * @return a time formatter.
     */
    public final static DateFormat getTimeInstance(int style)
    {
        return get(style, 0, 1, Locale.getDefault());
    }

    /**
     * Gets the time formatter with the given formatting style
     * for the given locale.
     * @param style the given formatting style. For example,
     * SHORT for "h:mm a" in the US locale.
     * @param aLocale the given locale.
     * @return a time formatter.
     */
    public final static DateFormat getTimeInstance(int style,
                                                 Locale aLocale)
    {
        return get(style, 0, 1, aLocale);
    }

    /**
     * Gets the date formatter with the default formatting style
     * for the default locale.
     * @return a date formatter.
     */
    public final static DateFormat getDateInstance()
    {
        return get(0, DEFAULT, 2, Locale.getDefault());
    }

    /**
     * Gets the date formatter with the given formatting style
     * for the default locale.
     * @param style the given formatting style. For example,
     * SHORT for "M/d/yy" in the US locale.
     * @return a date formatter.
     */
    public final static DateFormat getDateInstance(int style)
    {
        return get(0, style, 2, Locale.getDefault());
    }

    /**
     * Gets the date formatter with the given formatting style
     * for the given locale.
     * @param style the given formatting style. For example,
     * SHORT for "M/d/yy" in the US locale.
     * @param aLocale the given locale.
     * @return a date formatter.
     */
    public final static DateFormat getDateInstance(int style,
                                                 Locale aLocale)
    {
        return get(0, style, 2, aLocale);
    }

    /**
     * Gets the date/time formatter with the default formatting style
     * for the default locale.
     * @return a date/time formatter.
     */
    public final static DateFormat getDateTimeInstance()
    {
        return get(DEFAULT, DEFAULT, 3, Locale.getDefault());
    }

    /**
     * Gets the date/time formatter with the given date and time
     * formatting styles for the default locale.
     * @param dateStyle the given date formatting style. For example,
     * SHORT for "M/d/yy" in the US locale.
     * @param timeStyle the given time formatting style. For example,
     * SHORT for "h:mm a" in the US locale.
     * @return a date/time formatter.
     */
    public final static DateFormat getDateTimeInstance(int dateStyle,
                                                       int timeStyle)
    {
        return get(timeStyle, dateStyle, 3, Locale.getDefault());
    }

    /**
     * Gets the date/time formatter with the given formatting styles
     * for the given locale.
     * @param dateStyle the given date formatting style.
     * @param timeStyle the given time formatting style.
     * @param aLocale the given locale.
     * @return a date/time formatter.
     */
    public final static DateFormat
        getDateTimeInstance(int dateStyle, int timeStyle, Locale aLocale)
    {
        return get(timeStyle, dateStyle, 3, aLocale);
    }

    /**
     * Get a default date/time formatter that uses the SHORT style for both the
     * date and the time.
     */
    public final static DateFormat getInstance() {
        return getDateTimeInstance(SHORT, SHORT);
    }

    /**
     * Gets the set of locales for which DateFormats are installed.
     * @return the set of locales for which DateFormats are installed.
     */
    public static Locale[] getAvailableLocales()
    {
        return LocaleData.getAvailableLocales("DateTimePatterns");
    }

    /**
     * Set the calendar to be used by this date format.  Initially, the default
     * calendar for the specified or default locale is used.
     * @param newCalendar the new Calendar to be used by the date format
     */
    public void setCalendar(Calendar newCalendar)
    {
        this.calendar = newCalendar;
    }

    /**
     * Gets the calendar associated with this date/time formatter.
     * @return the calendar associated with this date/time formatter.
     */
    public Calendar getCalendar()
    {
        return calendar;
    }

    /**
     * Allows you to set the number formatter.
     * @param newNumberFormat the given new NumberFormat.
     */
    public void setNumberFormat(NumberFormat newNumberFormat)
    {
        this.numberFormat = newNumberFormat;
    }

    /**
     * Gets the number formatter which this date/time formatter uses to
     * format and parse a time.
     * @return the number formatter which this date/time formatter uses.
     */
    public NumberFormat getNumberFormat()
    {
        return numberFormat;
    }

    /**
     * Sets the time zone for the calendar of this DateFormat object.
     * @param zone the given new time zone.
     */
    public void setTimeZone(TimeZone zone)
    {
        calendar.setTimeZone(zone);
    }

    /**
     * Gets the time zone.
     * @return the time zone associated with the calendar of DateFormat.
     */
    public TimeZone getTimeZone()
    {
        return calendar.getTimeZone();
    }

    /**
     * Specify whether or not date/time parsing is to be lenient.  With
     * lenient parsing, the parser may use heuristics to interpret inputs that
     * do not precisely match this object's format.  With strict parsing,
     * inputs must match this object's format.
     * @param lenient when true, parsing is lenient