Android SimpleDateFormat, how to use it?

String _Date = "2010-09-29 08:45:22"
SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd");
SimpleDateFormat fmt2 = new SimpleDateFormat("dd-MM-yyyy");
    try {
        Date date = fmt.parse(_Date);
        return fmt2.format(date);
    }
    catch(ParseException pe) {

        return "Date";    
    }

try this.

Below is all date formats available, read more doc here.

Symbol  Meaning                Kind         Example
D       day in year             Number        189
E       day of week             Text          E/EE/EEE:Tue, EEEE:Tuesday, EEEEE:T
F       day of week in month    Number        2 (2nd Wed in July)
G       era designator          Text          AD
H       hour in day (0-23)      Number        0
K       hour in am/pm (0-11)    Number        0
L       stand-alone month       Text          L:1 LL:01 LLL:Jan LLLL:January LLLLL:J
M       month in year           Text          M:1 MM:01 MMM:Jan MMMM:January MMMMM:J
S       fractional seconds      Number        978
W       week in month           Number        2
Z       time zone (RFC 822)     Time Zone     Z/ZZ/ZZZ:-0800 ZZZZ:GMT-08:00 ZZZZZ:-08:00
a       am/pm marker            Text          PM
c       stand-alone day of week Text          c/cc/ccc:Tue, cccc:Tuesday, ccccc:T
d       day in month            Number        10
h       hour in am/pm (1-12)    Number        12
k       hour in day (1-24)      Number        24
m       minute in hour          Number        30
s       second in minute        Number        55
w       week in year            Number        27
G       era designator          Text          AD
y       year                    Number        yy:10 y/yyy/yyyy:2010
z       time zone               Time Zone     z/zz/zzz:PST zzzz:Pacific Standard 

I think this Link might helps you

OR

    Date date = Calendar.getInstance().getTime();
    //
    // Display a date in day, month, year format
    //
    DateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
    String today = formatter.format(date);
    System.out.println("Today : " + today);

I assume you would like to reverse the date format?

SimpleDateFormat can be used for parsing and formatting. You just need two formats, one that parses the string and the other that returns the desired print out:

SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd");
Date date = fmt.parse(dateString);

SimpleDateFormat fmtOut = new SimpleDateFormat("dd-MM-yyyy");
return fmtOut.format(date);

Since Java 8:

DateTimeFormatter fmt = DateTimeFormatter.ofPattern("yyyy-MM-dd").withZone(ZoneOffset.UTC);
TemporalAccessor date = fmt.parse(dateString);
Instant time = Instant.from(date);

DateTimeFormatter fmtOut = DateTimeFormatter.ofPattern("dd-MM-yyyy").withZone(ZoneOffset.UTC);
return fmtOut.format(time);