Date and time formats are specified by date and time pattern
strings. Within date and time pattern strings, unquoted letters from
'A'
to 'Z'
and from 'a'
to
'z'
are interpreted as pattern letters representing the components
of a date or time string. Text can be quoted using single quotes
('
) to avoid interpretation. "''"
represents a single
quote. All other characters are not interpreted; they're simply copied into the
output string during formatting or matched against the input string during
parsing.
The following pattern letters are defined (all other characters from
'A'
to 'Z'
and from 'a'
to
'z'
are reserved):
Pattern letters are usually repeated, as their number determines the exact presentation:
Letter Date or Time Component Presentation Examples G
Era designator Text AD
y
Year Year 1996
;96
M
Month in year Month July
;Jul
;07
w
Week in year Number 27
W
Week in month Number 2
D
Day in year Number 189
d
Day in month Number 10
F
Day of week in month Number 2
E
Day in week Text Tuesday
;Tue
a
Am/pm marker Text PM
H
Hour in day (0-23) Number 0
k
Hour in day (1-24) Number 24
K
Hour in am/pm (0-11) Number 0
h
Hour in am/pm (1-12) Number 12
m
Minute in hour Number 30
s
Second in minute Number 55
S
Millisecond Number 978
z
Time zone General time zone Pacific Standard Time
;PST
;GMT-08:00
Z
Time zone RFC 822 time zone -0800
For parsing, if the number of pattern letters is more than 2, the year is interpreted literally, regardless of the number of digits. So using 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"),
SimpleDateFormat
must interpret the abbreviated year relative to
some century. It does this by adjusting dates to be within 80 years before and
20 years after the time the SimpleDateFormat
instance is created.
For example, using a pattern of "MM/dd/yy" and a SimpleDateFormat
instance created on Jan 1, 1997, 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 consisting of exactly two digits, as defined by
Character.isDigit(char)
,
will be parsed into the default century. Any other numeric string, such as a
one digit string, a three or more digit string, or a two digit string that
isn't all digits (for example, "-1"), is interpreted literally. So "01/02/3"
or "01/02/003" are parsed, using the same pattern, as Jan 2, 3 AD. Likewise,
"01/02/-3" is parsed as Jan 2, 4 BC.
GMTOffsetTimeZone:Hours must be between 0 and 23, and Minutes must be between 00 and 59. The format is locale independent and digits must be taken from the Basic Latin block of the Unicode standard.GMT
Sign Hours:
Minutes Sign: one of+ -
Hours: Digit Digit Digit Minutes: Digit Digit Digit: one of0 1 2 3 4 5 6 7 8 9
For parsing, RFC 822 time zones are also accepted.
RFC822TimeZone: Sign TwoDigitHours Minutes TwoDigitHours: Digit DigitTwoDigitHours must be between 00 and 23. Other definitions are as for general time zones.
For parsing, general time zones are also accepted.
SimpleDateFormat
also supports localized date and time pattern strings. In these
strings, the pattern letters described above may be replaced with other, locale
dependent, pattern letters. SimpleDateFormat
does not deal with the
localization of text other than the pattern letters; that's up to the client of
the class.
Date and Time Pattern Result "yyyy.MM.dd G 'at' HH:mm:ss z"
2001.07.04 AD at 12:08:56 PDT
"EEE, MMM d, ''yy"
Wed, Jul 4, '01
"h:mm a"
12:08 PM
"hh 'o''clock' a, zzzz"
12 o'clock PM, Pacific Daylight Time
"K:mm a, z"
0:08 PM, PDT
"yyyyy.MMMMM.dd GGG hh:mm aaa"
02001.July.04 AD 12:08 PM
"EEE, d MMM yyyy HH:mm:ss Z"
Wed, 4 Jul 2001 12:08:56 -0700
"yyMMddHHmmssZ"
010704120856-0700