Java DateTime Formatting

You can use following mechanism to get the date and time as a format you preferred. You need to use the Calendar class in the java.util package. It is possible to filter the date time using SimpleDateFormat class in the java.text package by passing the format to the constructor.

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

public String getTimeStamp(){
Calendar cal = Calendar.getInstance();
Date date = cal.getTime();

SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd_hhmmss");

String timeStamp = "";

try {
timeStamp = format.format(date);
} catch (Exception e1) {
   e1.printStackTrace();
}

return timeStamp;
}