Formatting

Date and Time Patterns

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):

LetterDate or Time ComponentExamples

G

Era designator

AD

y

Year

1996; 96

Y

Week year

2009; 09

M

Month in year (context sensitive)

July; Jul; 07

L

Month in year (standalone form)

July; Jul; 07

w

Week in year

27

W

Week in month

2

D

Day in year

189

d

Day in month

10

F

Day of week in month

2

E

Day name in week

Tuesday; Tue

u

Day number of week (1 = Monday, ..., 7 = Sunday)

1

a

Am/pm marker

PM

H

Hour in day (0-23)

0

k

Hour in day (1-24)

24

K

Hour in am/pm (0-11)

0

h

Hour in am/pm (1-12)

12

m

Minute in hour

30

s

Second in minute

55

S

Millisecond

978

z

Time zone

Pacific Standard Time; PST; GMT-08:00

Z

Time zone

-0800

X

Time zone

-08; -0800; -08:00

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 time zone.

Date and Time PatternResult

"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

"yyyy-MM-dd'T'HH:mm:ss.SSSXXX"

2001-07-04T12:08:56.235-07:00

"YYYY-'W'ww-u"

2001-W27-3

reference: https://docs.oracle.com/javase/8/docs/api/java/text/SimpleDateFormat.html