java date format格式化编码

Letter for Pattern	Date or Time component	Examples
G	Era designator	AD
y	Year	2018(yyyy),18(yy)
M	Month in year	July(MMMM), Jul(MMM), 07(MM)
w	Results in week in year	16
W	Results in week in month	3
D	Gives the day count in the year	266
d	Day of the month	09(dd), 9(d)
F	Day of the week in month	4
E	Day name in the week	Tuesday, Tue
u	Day number of week where 1 represents Monday, 2 represents Tuesday and so on	2
a	AM or PM marker	AM
H	Hour in the day (0-23)	12
k	Hour in the day (1-24)	23
K	Hour in am/pm for 12 hour format (0-11)	0
h	Hour in am/pm for 12 hour format (1-12)	12
m	Minute in the hour	9(m), 09(mm)
s	Second in the minute	35
S	Millisecond in the minute	978
z	Timezone	Pacific Standard Time; PST; GMT-08:00
Z	Timezone offset in hours (RFC pattern)	-0800
X	Timezone offset in ISO format	-08; -0800; -08:00