date.java

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     * replaced by <code>Calendar.set(year + 1900, month, date,
     * hrs, min, sec)</code> or <code>GregorianCalendar(year + 1900,
     * month, date, hrs, min, sec)</code>, using a UTC
     * <code>TimeZone</code>, followed by <code>Calendar.getTime().getTime()</code>.
     */
    public static long UTC(int year, int month, int date,
                           int hrs, int min, int sec) {
        if (utcCal == null)
            makeStaticCalendars();
        synchronized (utcCal) {
            utcCal.clear();
            utcCal.set(year + 1900, month, date, hrs, min, sec);
            return utcCal.getTimeInMillis();
        }
    }

    /**
     * Attempts to interpret the string <tt>s</tt> as a representation 
     * of a date and time. If the attempt is successful, the time 
     * indicated is returned represented as the distance, measured in 
     * milliseconds, of that time from the epoch (00:00:00 GMT on 
     * January 1, 1970). If the attempt fails, an 
     * <tt>IllegalArgumentException</tt> is thrown.
     * <p>
     * It accepts many syntaxes; in particular, it recognizes the IETF 
     * standard date syntax: "Sat, 12 Aug 1995 13:30:00 GMT". It also 
     * understands the continental U.S. time-zone abbreviations, but for 
     * general use, a time-zone offset should be used: "Sat, 12 Aug 1995 
     * 13:30:00 GMT+0430" (4 hours, 30 minutes west of the Greenwich 
     * meridian). If no time zone is specified, the local time zone is 
     * assumed. GMT and UTC are considered equivalent.
     * <p>
     * The string <tt>s</tt> is processed from left to right, looking for 
     * data of interest. Any material in <tt>s</tt> that is within the 
     * ASCII parenthesis characters <tt>(</tt> and <tt>)</tt> is ignored. 
     * Parentheses may be nested. Otherwise, the only characters permitted 
     * within <tt>s</tt> are these ASCII characters:
     * <blockquote><pre>
     * abcdefghijklmnopqrstuvwxyz
     * ABCDEFGHIJKLMNOPQRSTUVWXYZ
     * 0123456789,+-:/</pre></blockquote>
     * and whitespace characters.<p>
     * A consecutive sequence of decimal digits is treated as a decimal 
     * number:<ul>
     * <li>If a number is preceded by <tt>+</tt> or <tt>-</tt> and a year 
     *     has already been recognized, then the number is a time-zone 
     *     offset. If the number is less than 24, it is an offset measured 
     *     in hours. Otherwise, it is regarded as an offset in minutes, 
     *     expressed in 24-hour time format without punctuation. A 
     *     preceding <tt>-</tt> means a westward offset. Time zone offsets 
     *     are always relative to UTC (Greenwich). Thus, for example, 
     *     <tt>-5</tt> occurring in the string would mean "five hours west 
     *     of Greenwich" and <tt>+0430</tt> would mean "four hours and 
     *     thirty minutes east of Greenwich." It is permitted for the 
     *     string to specify <tt>GMT</tt>, <tt>UT</tt>, or <tt>UTC</tt> 
     *     redundantly-for example, <tt>GMT-5</tt> or <tt>utc+0430</tt>.
     * <li>The number is regarded as a year number if one of the
     *     following conditions is true:
     * <ul>
     *     <li>The number is equal to or greater than 70 and followed by a
     *         space, comma, slash, or end of string
     *     <li>The number is less than 70, and both a month and a day of
     *         the month have already been recognized</li>
     * </ul>
     *     If the recognized year number is less than 100, it is
     *     interpreted as an abbreviated year relative to a century of
     *     which dates are within 80 years before and 19 years after
     *     the time when the Date class is initialized.
     *     After adjusting the year number, 1900 is subtracted from
     *     it. For example, if the current year is 1999 then years in
     *     the range 19 to 99 are assumed to mean 1919 to 1999, while
     *     years from 0 to 18 are assumed to mean 2000 to 2018.  Note
     *     that this is slightly different from the interpretation of
     *     years less than 100 that is used in {@link java.text.SimpleDateFormat}.
     * <li>If the number is followed by a colon, it is regarded as an hour, 
     *     unless an hour has already been recognized, in which case it is 
     *     regarded as a minute.
     * <li>If the number is followed by a slash, it is regarded as a month 
     *     (it is decreased by 1 to produce a number in the range <tt>0</tt> 
     *     to <tt>11</tt>), unless a month has already been recognized, in 
     *     which case it is regarded as a day of the month.
     * <li>If the number is followed by whitespace, a comma, a hyphen, or 
     *     end of string, then if an hour has been recognized but not a 
     *     minute, it is regarded as a minute; otherwise, if a minute has 
     *     been recognized but not a second, it is regarded as a second; 
     *     otherwise, it is regarded as a day of the month. </ul><p>
     * A consecutive sequence of letters is regarded as a word and treated 
     * as follows:<ul>
     * <li>A word that matches <tt>AM</tt>, ignoring case, is ignored (but 
     *     the parse fails if an hour has not been recognized or is less 
     *     than <tt>1</tt> or greater than <tt>12</tt>).
     * <li>A word that matches <tt>PM</tt>, ignoring case, adds <tt>12</tt> 
     *     to the hour (but the parse fails if an hour has not been 
     *     recognized or is less than <tt>1</tt> or greater than <tt>12</tt>).
     * <li>Any word that matches any prefix of <tt>SUNDAY, MONDAY, TUESDAY, 
     *     WEDNESDAY, THURSDAY, FRIDAY</tt>, or <tt>SATURDAY</tt>, ignoring 
     *     case, is ignored. For example, <tt>sat, Friday, TUE</tt>, and 
     *     <tt>Thurs</tt> are ignored.
     * <li>Otherwise, any word that matches any prefix of <tt>JANUARY, 
     *     FEBRUARY, MARCH, APRIL, MAY, JUNE, JULY, AUGUST, SEPTEMBER, 
     *     OCTOBER, NOVEMBER</tt>, or <tt>DECEMBER</tt>, ignoring case, and 
     *     considering them in the order given here, is recognized as
     *     specifying a month and is converted to a number (<tt>0</tt> to 
     *     <tt>11</tt>). For example, <tt>aug, Sept, april</tt>, and 
     *     <tt>NOV</tt> are recognized as months. So is <tt>Ma</tt>, which 
     *     is recognized as <tt>MARCH</tt>, not <tt>MAY</tt>.
     * <li>Any word that matches <tt>GMT, UT</tt>, or <tt>UTC</tt>, ignoring 
     *     case, is treated as referring to UTC. 
     * <li>Any word that matches <tt>EST, CST, MST</tt>, or <tt>PST</tt>, 
     *     ignoring case, is recognized as referring to the time zone in 
     *     North America that is five, six, seven, or eight hours west of 
     *     Greenwich, respectively. Any word that matches <tt>EDT, CDT, 
     *     MDT</tt>, or <tt>PDT</tt>, ignoring case, is recognized as 
     *     referring to the same time zone, respectively, during daylight 
     *     saving time.</ul><p>
     * Once the entire string s has been scanned, it is converted to a time 
     * result in one of two ways. If a time zone or time-zone offset has been 
     * recognized, then the year, month, day of month, hour, minute, and 
     * second are interpreted in UTC and then the time-zone offset is 
     * applied. Otherwise, the year, month, day of month, hour, minute, and 
     * second are interpreted in the local time zone.
     *
     * @param   s   a string to be parsed as a date.
     * @return  the number of milliseconds since January 1, 1970, 00:00:00 GMT
     *          represented by the string argument.
     * @see     java.text.DateFormat
     * @deprecated As of JDK version 1.1,
     * replaced by <code>DateFormat.parse(String s)</code>.
     */
    public static long parse(String s) {
        if (staticCal == null)
            makeStaticCalendars(); // Called only for side-effect of setting defaultCenturyStart
        
        int year = Integer.MIN_VALUE;
        int mon = -1;
        int mday = -1;
        int hour = -1;
        int min = -1;
        int sec = -1;
        int millis = -1;
        int c = -1;
        int i = 0;
        int n = -1;
        int wst = -1;
        int tzoffset = -1;
        int prevc = 0;
    syntax:
        {
            if (s == null)
                break syntax;
            int limit = s.length();
            while (i < limit) {
                c = s.charAt(i);
                i++;
                if (c <= ' ' || c == ',')
                    continue;
                if (c == '(') { // skip comments
                    int depth = 1;
                    while (i < limit) {
                        c = s.charAt(i);
                        i++;
                        if (c == '(') depth++;
                        else if (c == ')')
                            if (--depth <= 0)
                                break;
                    }
                    continue;
                }
                if ('0' <= c && c <= '9') {
                    n = c - '0';
                    while (i < limit && '0' <= (c = s.charAt(i)) && c <= '9') {
                        n = n * 10 + c - '0';
                        i++;
                    }
                    if (prevc == '+' || prevc == '-' && year != Integer.MIN_VALUE) {
                        // timezone offset
                        if (n < 24)
                            n = n * 60; // EG. "GMT-3"
                        else
                            n = n % 100 + n / 100 * 60; // eg "GMT-0430"
                        if (prevc == '+')   // plus means east of GMT
                            n = -n;
                        if (tzoffset != 0 && tzoffset != -1)
                            break syntax;
                        tzoffset = n;
                    } else if (n >= 70)
                        if (year != Integer.MIN_VALUE)
                            break syntax;
                        else if (c <= ' ' || c == ',' || c == '/' || i >= limit)
                            // year = n < 1900 ? n : n - 1900;
                            year = n;
                        else
                            break syntax;
                    else if (c == ':')
                        if (hour < 0)
                            hour = (byte) n;
                        else if (min < 0)
                            min = (byte) n;
                        else
                            break syntax;
                    else if (c == '/')
                        if (mon < 0)
                            mon = (byte) (n - 1);
                        else if (mday < 0)
                            mday = (byte) n;
                        else
                            break syntax;
                    else if (i < limit && c != ',' && c > ' ' && c != '-')
                        break syntax;
                    else if (hour >= 0 && min < 0)
                        min = (byte) n;
                    else if (min >= 0 && sec < 0)
                        sec = (byte) n;
                    else if (mday < 0)
                        mday = (byte) n;
                    // Handle two-digit years < 70 (70-99 handled above).
                    else if (year == Integer.MIN_VALUE && mon >= 0 && mday >= 0)
                        year = n;
                    else
                        break syntax;
                    prevc = 0;
                } else if (c == '/' || c == ':' || c == '+' || c == '-')
                    prevc = c;
                else {
                    int st = i - 1;
                    while (i < limit) {
                        c = s.charAt(i);
                        if (!('A' <= c && c <= 'Z' || 'a' <= c && c <= 'z'))
                            break;
                        i++;
                    }
                    if (i <= st + 1)
                        break syntax;
                    int k;
                    for (k = wtb.length; --k >= 0;)
                        if (wtb[k].regionMatches(true, 0, s, st, i - st)) {
                            int action = ttb[k];
                            if (action != 0) {
                                if (action == 1) {  // pm
                                    if (hour > 12 || hour < 1)
                                        break syntax;
                                    else if (hour < 12)
                                        hour += 12;
                                } else if (action == 14) {  // am
                                    if (hour > 12 || hour < 1)
                                        break syntax;
                                    else if (hour == 12)
                                        hour = 0;
                                } else if (action <= 13) {  // month!
                                    if (mon < 0)
                                        mon = (byte) (action - 2);
                                    else
                                        break syntax;
                                } else {
                                    tzoffset = action - 10000;
                                }
                            }
                            break;
                        }
                    if (k < 0)
                        break syntax;
                    prevc = 0;
                }
            }
            if (year == Integer.MIN_VALUE || mon < 0 || mday < 0)
                break syntax;
            // Parse 2-digit years within the correct default century.
            if (year < 100) {
                year += (defaultCenturyStart / 100) * 100;
                if (year < defaultCenturyStart) year += 100;
            }
            year -= 1900;
            if (sec < 0)
                sec = 0;
            if (min < 0)
                min = 0;
            if (hour < 0)
                hour = 0;
            if (tzoffset == -1) // no time zone specified, have to use local
                return new Date (year, mon, mday, hour, min, sec).getTime();
            return UTC(year, mon, mday, hour, min, sec) + tzoffset * (60 * 1000);
        }
        // syntax error
        throw new IllegalArgumentException();
    }
    private final static String wtb[] = {
        "am", "pm",
        "monday", "tuesday", "wednesday", "thursday", "friday",
        "saturday", "sunday",
        "january", "february", "march", "april", "may", "june",
        "july", "august", "september", "october", "november", "december",
        "gmt", "ut", "utc", "est", "edt", "cst", "cdt",
        "mst", "mdt", "pst", "pdt"
        // this time zone table needs to be expanded
    };
    private final static int ttb[] = {
        14, 1, 0, 0, 0, 0, 0, 0, 0,
        2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,