Formatting and parsing date-time patterns

Text

For formatting, if the number of pattern letters is four or more, the full form is used. Otherwise, a short or abbreviated form is used if available. For parsing, both forms are accepted, independent of the number of pattern letters.

Number

For formatting, the number of pattern letters is the minimum number of digits, and shorter numbers are zero-padded to this amount. For parsing, the number of pattern letters is ignored unless it is needed to separate two adjacent fields.

Year

For formatting, if two pattern letters are used, the year is truncated to two digits. Otherwise, the year is interpreted as a number.

For parsing, if the number of pattern letters is more than two, the year is interpreted literally, regardless of the number of digits. For example, the pattern "MM/dd/yyyy", "01/11/12" parses to Jan 11, 12 A.D.

For parsing with the abbreviated year pattern ("y" or "yy"), Rational Integration Tester interprets the abbreviated year relative to the century by adjusting dates to be within 80 years before and 20 years after the current date/time.

Take for example that the current date/time is January 1, 1997 and you use a pattern of "MM/dd/yy". The string "01/11/12" would be interpreted as Jan 11, 2012, while the string "05/04/64" would be interpreted as May 4, 1964.

During parsing, only strings that consist of exactly two digits are parsed into the default century. Any other numeric string is interpreted literally. Examples are a one-digit string, three or more digit strings, or a two-digit string that is not all digits ("-1"). So "01/02/3" or "01/02/003" are parsed, by using the same pattern, as Jan 2, 3 AD. Likewise, "01/02/-3" is parsed as Jan 2, 4 BC.

Month

If the number of pattern letters is three or more, the month is interpreted as text. Otherwise, the month is interpreted as a number.

General time zone

Time zones are interpreted as text if they have names. For time zones that represent a GMT offset value, the following syntax is used: GMT +/- Hours:Minutes, which represents GMT plus or minus some offset time in hours and minutes.

Hours must be 0 - 23, and they can be expressed as a single digit or as two digits (for example, 3:00 or 11:00). Minutes must be 00 - 59, and they must be expressed as two digits.

For parsing, RFC 822 time zones are also accepted.

RFC 822 time zone

For formatting, the RFC 822 4-digit time zone format is used: +/-HHmm, which represents the current offset from GMT in hours and minutes.

Hours must be 00 - 23, always expressed as two digits, and minutes must be 00 - 59.

For parsing, general time zones are also accepted.

Examples

The following examples show how date and time patterns are interpreted in the U.S. locale. The date and time are 2001-07-04 12:08:56 local time in the U.S. Pacific Time time zone.