Formats and parses date specification based on the
draft-ietf-drums-msg-fmt-08 dated January 26, 2000.
This is a followup spec to RFC822.
This class does not take pattern strings.
It always formats the date based on the specification below.
3.3 Date and Time Specification
Date and time occur in several header fields of a message. This section
specifies the syntax for a full date and time specification. Though folding
whitespace is permitted throughout the date-time specification, it is
recommended that only a single space be used where FWS is required and
no space be used where FWS is optional in the date-time specification;
some older implementations may not interpret other occurrences of folding
whitespace correctly.
date-time = [ day-of-week "," ] date FWS time [CFWS]
day-of-week = ([FWS] day-name) / obs-day-of-week
day-name = "Mon" / "Tue" / "Wed" / "Thu" / "Fri" / "Sat" / "Sun"
date = day month year
year = 4*DIGIT / obs-year
month = (FWS month-name FWS) / obs-month
month-name = "Jan" / "Feb" / "Mar" / "Apr" /
"May" / "Jun" / "Jul" / "Aug" /
"Sep" / "Oct" / "Nov" / "Dec"
day = ([FWS] 1*2DIGIT) / obs-day
time = time-of-day FWS zone
time-of-day = hour ":" minute [ ":" second ]
hour = 2DIGIT / obs-hour
minute = 2DIGIT / obs-minute
second = 2DIGIT / obs-second
zone = (( "+" / "-" ) 4DIGIT) / obs-zone
The day is the numeric day of the month.
The year is any numeric year in the common era.
The time-of-day specifies the number of hours, minutes, and optionally
seconds since midnight of the date indicated.
The date and time-of-day SHOULD express local time.
The zone specifies the offset from Coordinated Universal Time(UTC,
formerly referred to as "Greenwich Mean Time") that the date and
time-of-day represent.
The "+" or "-" indicates whether the time-of-day is ahead of or behind
Universal Time. The first two digits indicate the number of hours'
difference from Universal Time, and the last two digits indicate the
number of minutes' difference from Universal Time.(Hence, +hhmm means
+(hh * 60 + mm) minutes, and -hhmm means -(hh * 60 + mm) minutes).
The form "+0000" SHOULD be used to indicate a time zone at Universal Time.
Though "-0000" also indicates Universal Time, it is used to indicate that
the time was generated on a system that may be in a local time zone other
than Universal Time.
A date-time specification MUST be semantically valid.
That is, the day-of-the week(if included) MUST be the day implied by
the date, the numeric day-of-month MUST be between 1 and the number of
days allowed for the specified month(in the specified year), the
time-of-day MUST be in the range 00:00:00 through 23:59:60(the number
of seconds allowing for a leap second; see [STD-12]), and the zone MUST
be within the range -9959 through +9959.
format
public StringBuffer format(Date date,
StringBuffer buf,
FieldPosition field)
Appends the textual value for the specified field to the given string
buffer. This method should be avoided, use format(Date)
instead.
date
- the Date objectbuf
- the buffer to append tofield
- the current field position
- the modified buffer
parse
public Date parse(String text,
ParsePosition pos)
Parses the given date in the format specified by
draft-ietf-drums-msg-fmt-08 in the current TimeZone.
text
- the formatted date to be parsedpos
- the current parse position
setCalendar
public void setCalendar(Calendar newCalendar)
Don't allow setting the calendar.
setNumberFormat
public void setNumberFormat(NumberFormat newNumberFormat)
Don't allow setting the NumberFormat.