File	Doc	Category	Size	Date	Package
DateParser.java	API Doc	J2ME MIDP 2.0	22426	Thu Nov 07 12:02:20 GMT 2002	com.sun.midp.io

DateParser

• java.lang.Object

Fields Summary
protected int	year The year represented by this date
protected int	month The month represented by this date
protected int	day The day of the month represented by this date
protected int	hour The hour represented by this date
protected int	minute The minute represented by this date
protected int	second The second represented by this date
protected int	milli The millisecond represented by this date
protected int	tzoffset The offset, in milliseconds, from GMT represented by this date
protected static int	local_tz The offset, in milliseconds, from GMT for the local time zone
private static Hashtable	timezones A table of valid timezones
private int[]	days_in_month Number of days in each month in a non leap year
private String[]	month_shorts Short versions of the month strings
private String[]	weekday_shorts Short versions of the weekday strings
private static long	julianDayOffset Offset from Jan 1, year 1 (Julian) and Jan 1, 1970
private static int	millisPerHour Number of milliseconds per hour
private static int	millisPerDay Number of milliseconds per day
private static final int	JAN_1_1_JULIAN_DAY Jan 1, year 1 (Gregorian)
private static final String[]	wtb All of the valid strings for the date
private static final int[]	ttb Used to process date strings. Each value coresponds to a string in the wtb variable.
private static final int[]	NUM_DAYS Cummulative number of days for each month in a non leap year.
private static final int[]	LEAP_NUM_DAYS Cummulative number of days for each month in a leap year.

Constructors Summary
DateParser(int year, int month, int day, int hour, int minute, int second) Allocates a DateParser object and initializes it so that it represents the instant at the start of the second specified by the year, month, date, hrs, min, and sec arguments, in the local time zone. param year the year, >= 1583. param month the month between 0-11. param day the day of the month between 1-31. param hour the hours between 0-23. param minute the minutes between 0-59. param second the seconds between 0-59. if (year < 1583 || month < 0 || month > 11 || day < 0 || (day > days_in_month[month] && !(month == 1 && day == 29 && year % 4 == 0)) || hour < 0 || hour > 23 || minute < 0 || minute > 59 || second < 0 || second > 59) { throw new IllegalArgumentException(); } this.year = year; this.month = month; this.day = day; this.hour = hour; this.minute = minute; this.second = second; milli = 0;
DateParser(String s) Allocates a DateParser object and initializes it so that it represents the date and time indicated by the string s, which is interpreted as if by the {@link DateParser#parse} method. param s a string representation of the date. internalParse(s);

Methods Summary
private final long	computeJulianDay(int year, int month, int day) Calculate the number of Julian days since Jan 1, year 1 as represented by the year, month, and day. param year The Gegorian year param month The month param day The day of the month month return the number of Julian days. int y; long millis = 0; boolean isLeap = year%4 == 0; y = year - 1; long julianDay = 365L*y + floorDivide(y, 4) + (JAN_1_1_JULIAN_DAY - 3); isLeap = isLeap && ((year%100 != 0) || (year%400 == 0)); // Add 2 because Gregorian calendar starts 2 days after Julian calendar julianDay += floorDivide(y, 400) - floorDivide(y, 100) + 2; julianDay += isLeap ? LEAP_NUM_DAYS[month] : NUM_DAYS[month]; julianDay += day; return julianDay;
private static final long	floorDivide(long numerator, long denominator) Divide two long integers, returning the floor of the quotient. Unlike the built-in division, this is mathematically well-behaved. E.g., -1/4 => 0 but floorDivide(-1,4) => -1. param numerator the numerator param denominator a divisor which must be > 0 return the floor of the quotient. // We do this computation in order to handle // a numerator of Long.MIN_VALUE correctly return (numerator >= 0) ? numerator / denominator : ((numerator + 1) / denominator) - 1;
int	getDay() Get the day of the month represented by this date. return The day of the month. return day;
int	getHour() Get the hour represented by this date. return The hour. return hour;
int	getMinute() Get the minute represented by this date. return The minute. return minute;
int	getMonth() Get the month represented by this date. return The month. return month;
int	getSecond() Get the second represented by this date. return The second. return second;
long	getTime() Calculate the number of milliseconds since 01/01/1970 represented by this date. return the number of milliseconds. long julianDay = computeJulianDay(year, month, day); long millis = julianDayToMillis(julianDay); int millisInDay = 0; millisInDay += hour; millisInDay *= 60; millisInDay += minute; // now have minutes millisInDay *= 60; millisInDay += second; // now have seconds millisInDay *= 1000; millisInDay += milli; // now have millis return millis + millisInDay - tzoffset;
int	getYear() Get the year represented by this date. return The year. return year;
private void	internalParse(java.lang.String s) Parse the date string s param s a string representation of the date. int year = -1; 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 >= 0) { // 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 >= 0) break syntax; else if (c <= ' " || c == '," || c == '/" || i >= limit) // year = n < 1900 ? n : n - 1900; year = n < 100 ? n + 1900 : 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; 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 < 1583 || mon < 0 || mday < 0) break syntax; if (sec < 0) sec = 0; if (min < 0) min = 0; if (hour < 0) hour = 0; this.year = year; month = mon; day = mday; this.hour = hour; this.tzoffset = -tzoffset * 60 * 1000; minute = min; second = sec; milli = 0; return; } // syntax error throw new IllegalArgumentException();
private long	julianDayToMillis(long julian) Convert the Julian day, julian into milliseconds. param julian Number of days since Jan 1, year 1 (Julian). return the number of millis since the 01/01/1970. return (julian - julianDayOffset) * millisPerDay;
public static long	parse(java.lang.String s) Attempts to interpret the string s as a representation of a date and time. If the attempt is successful, the time indicated is returned represented as teh distance, measured in milliseconds, of that time from the epoch (00:00:00 GMT on January 1, 1970). If the attempt fails, an IllegalArgumentException is thrown. 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. The string s is processed from left to right, looking for data of interest. Any material in s that is within the ASCII parenthesis characters ( and ) is ignored. Parentheses may be nested. Otherwise, the only characters permitted within s are these ASCII characters: abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ 0123456789,+-:/ and whitespace characters. A consecutive sequence of decimal digits is treated as a decimal number: If a number is preceded by + or - 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 - means a westward offset. Time zone offsets are always relative to UTC (Greenwich). Thus, for example, -5 occurring in the string would mean "five hours west of Greenwich" and +0430 would mean "four hours and thirty minutes east of Greenwich." It is permitted for the string to specify GMT, UT, or UTC redundantly-for example, GMT-5 or utc+0430. If a number is greater than 70, it is regarded as a year number. It must be followed by a space, comma, slash, or end of string. 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. 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 0 to 11), unless a month has already been recognized, in which case it is regarded as a day of the month. 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. A consecutive sequence of letters is regarded as a word and treated as follows: A word that matches AM, ignoring case, is ignored (but the parse fails if an hour has not been recognized or is less than 1 or greater than 12). A word that matches PM, ignoring case, adds 12 to the hour (but the parse fails if an hour has not been recognized or is less than 1 or greater than 12). Any word that matches any prefix of SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, or SATURDAY, ignoring case, is ignored. For example, sat, Friday, TUE, and Thurs are ignored. Otherwise, any word that matches any prefix of JANUARY, FEBRUARY, MARCH, APRIL, MAY, JUNE, JULY, AUGUST, SEPTEMBER, OCTOBER, NOVEMBER, or DECEMBER, ignoring case, and considering them in the order given here, is recognized as specifying a month and is converted to a number (0 to 11). For example, aug, Sept, april, and NOV are recognized as months. So is Ma, which is recognized as MARCH, not MAY. Any word that matches GMT, UT, or UTC, ignoring case, is treated as referring to UTC. Any word that matches EST, CST, MST, or PST, 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 EDT, CDT, MDT, or PDT, ignoring case, is recognized as referring to the same time zone, respectively, during daylight saving time. 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 distance in milliseconds from January 1, 1970, 00:00:00 GMT represented by the string argument. Note that this method will throw an IllegalArgumentException if the year indicated in s is less than 1583. return (new DateParser(s)).getTime();
static void	setTimeZone(java.lang.String tz) Set the local time zone for the DateParser class. tz must in abbreviated format, e.g. "PST" for Pacific Standard Time. param tz The time zone string in abbreviated format. if (timezones.get(tz) == null) { return; } local_tz = ((Integer)timezones.get(tz)).intValue();