Date and Time Patterns

Date and time formats are specified by date and time pattern strings. In these pattern strings, unquoted letters from A to Z and from a to z represent components of a data or time value. If a letter or text string is enclosed within a pair of single quotes, that letter or text is not interpreted but rather used as is, as are all other characters in the pattern string. During printing, that letter or text is copied as is to the output string; during parsing, they are matched against the input string. "''" represents a single quote.

The following pattern letters are defined for the indicated Date or Time Component. All other characters from 'A' to 'Z' and from 'a' to 'z' are reserved. For an alphabetic ordering of the pattern letters, see Date and Time Pattern Letters in Alphabetic Order.

Date or Time Component	Pattern Letter	Presentation as text or number	Examples
Era designator	G	Text	AD
Year	y	Year	1996; 96
Month in year	M	Month	July; Jul; 07
Week in year	w	Number	27
Week in month	W	Number	2
Day in year	D	Number	189
Day in month	d	Number	10
Day of week in month	F	Number	2
Day in week	E	Text	EE=Tu; EEE=Tue; EEEE=Tuesday
Am/pm marker	a	Text	PM
Hour in day (0-23)	H	Number	0
Hour in day (1-24)	k	Number	24
Hour in am/pm (0-11)	K	Number	0
Hour in am/pm (1-12)	h	Number	12
Minute in hour	m	Number	30
Second in minute	s	Number	55
Millisecond	S	Number	978
Time zone	z	General	Pacific Standard Time; PST; GMT-08:00
Time zone	Z	RFC	-0800

Pattern letters are usually repeated, as their number determines the exact presentation:

Text

For formatting, if the number of pattern letters is 4 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's needed to separate two adjacent fields.

Year

Time zones are interpreted as text if they have names. For time zones representing a GMT offset value, the following syntax is used:

GMTOffsetTimeZone:
GMT Sign Hours : Minutes
Sign: one of
+ -
Hours:
Digit
Digit Digit
Minutes:
Digit Digit
Digit: one of
0 1 2 3 4 5 6 7 8 9

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.

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:

RFC822TimeZone:
Sign TwoDigitHours Minutes
TwoDigitHours:
Digit Digit

TwoDigitHours 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.

Examples

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

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
"yyyy-MM-dd'T'HH:mm:ss.SSSZ"	2001-07-04T12:08:56.235-0700

Date and Time Pattern Letters in Alphabetic Order

The same pattern letters shown at first, above, in Date or Time Component order are shown below in alphabetic order for easy reference.

Pattern Letter	Date or Time Component	Presentation as text or number	Examples
a	Am/pm marker	Text	PM
D	Day in year	Number	189
d	Day in month	Number	10
E	Day in week	Text	EE=Tu; EEE=Tue; EEEE=Tuesday
F	Day of week in month	Number	2
G	Era designator	Text	AD
H	Hour in day (0-23)	Number	0
h	Hour in am/pm (1-12)	Number	12
k	Hour in day (1-24)	Number	24
K	Hour in am/pm (0-11)	Number	0
M	Month in year	Month	July; Jul; 07
m	Minute in hour	Number	30
s	Second in minute	Number	55
S	Millisecond	Number	978
w	Week in year	Number	27
W	Week in month	Number	2
y	Year	Year	1996; 96
z	Time zone	General	Pacific Standard Time; PST; GMT-08:00
Z	Time zone	RFC	-0800