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Setting and formatting time zone with Calendar object in Java and then returning a Date object

I have a function where I need to grab the current date, set to another time zone, and return that converted/formatted date as a Date object. I have code that works, however, the Date object does not set to the newly converted date, it returns the current date.
Here is the code:
public static Date getCurrentLocalDateTime() {
Calendar currentdate = Calendar.getInstance();
DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
TimeZone obj = TimeZone.getTimeZone("America/Denver");
formatter.setTimeZone(obj);
Logger.info("Local:: " + currentdate.getTime());
String formattedDate = formatter.format(currentdate.getTime());
Logger.info("America/Denver:: "+ formattedDate);
Date finalDate = null;
try {
finalDate = formatter.parse(formattedDate);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Logger.info("finalDate:: " + finalDate);
return finalDate;
}
From the examples I have reviewed and tried, this should work correctly. One of the issues is that I need to return the Date object so it works with the current code.
The output looks like:
2017-07-03 17:08:24,499 [INFO] from application in application-akka.actor.default-dispatcher-3 -
Local:: Mon Jul 03 17:08:24 UTC 2017
2017-07-03 17:08:24,501 [INFO] from application in application-akka.actor.default-dispatcher-3 -
America/Denver:: 2017-07-03 11:08:24
2017-07-03 17:08:24,502 [INFO] from application in application-akka.actor.default-dispatcher-3 -
finalDate:: Mon Jul 03 17:08:24 UTC 2017
As you can see, it formats the date correctly to the Mountain Time Zone, but then sets it back to the Calendar time.
EDIT --- Code solution:
public static Date getCurrentLocalDateTime() {
Calendar currentdate = Calendar.getInstance();
ZonedDateTime converted = currentdate.toInstant().atZone(ZoneId.of("America/Denver"))
.withZoneSameLocal(ZoneOffset.UTC);
Date finalDate = Date.from(converted.toInstant());
return finalDate;
}

A java.util.Date object has no timezone information. It has only a long value, which is the number of milliseconds from 1970-01-01T00:00:00Z (also known as "unix epoch" or just "epoch"). This value is absolutely independent of timezone (you can say "it's in UTC" as well).
When you call Logger.info("finalDate:: " + finalDate);, it calls the toString() method of java.util.Date, and this method uses the system's default timezone behind the scenes, giving the impression that the date object itself has a timezone - but it doesn't.
Check the values of finalDate.getTime() and currentdate.getTimeInMillis(), you'll see they are almost the same - "almost" because the SimpleDateFormat doesn't have the fraction of seconds, so you're losing the milliseconds precision (format method creates a String without the milliseconds, and the parse method sets it to zero when the field is not present). If I change the formatter to this, though:
// using ".SSS" to don't lose milliseconds when formatting
DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
The output is:
Local:: Mon Jul 03 17:34:34 UTC 2017
America/Denver:: 2017-07-03 11:34:34.508
finalDate:: Mon Jul 03 17:34:34 UTC 2017
And both finalDate.getTime() and currentdate.getTimeInMillis() will have exactly the same values (Note that Date.toString() doesn't print the milliseconds, so you can't know what's their value - only by comparing getTime() values you know if they are the same).
Conclusion: just change your formatter to use the milliseconds (.SSS) and parsing/formatting will work. The fact that it shows the dates in another timezone is an implementation detail (toString() method uses system's default timezone), but the milliseconds value is correct.
If you want to get 11h at UTC, you must create another formatter and set its timezone to UTC:
DateFormat parser = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
parser.setTimeZone(TimeZone.getTimeZone("UTC"));
finalDate = parser.parse(formattedDate);
Then, finalDate's time will have the value of 11h at UTC:
finalDate:: Mon Jul 03 11:34:34 UTC 2017
New Java Date/Time API
The old classes (Date, Calendar and SimpleDateFormat) have lots of problems and design issues, and they're being replaced by the new APIs.
If you're using Java 8, consider using the new java.time API. It's easier, less bugged and less error-prone than the old APIs.
If you're using Java <= 7, you can use the ThreeTen Backport, a great backport for Java 8's new date/time classes. And for Android, there's the ThreeTenABP (more on how to use it here).
The code below works for both.
The only difference is the package names (in Java 8 is java.time and in ThreeTen Backport (or Android's ThreeTenABP) is org.threeten.bp), but the classes and methods names are the same.
To do what you need, you can use a ZonedDateTime (a date and time + a timezone) and convert to another timezone keeping the same date/time values:
// current date/time in Denver
ZonedDateTime denverNow = ZonedDateTime.now(ZoneId.of("America/Denver"));
// convert to UTC, but keeping the same date/time values (like 11:34)
ZonedDateTime converted = denverNow.withZoneSameLocal(ZoneOffset.UTC);
System.out.println(converted); // 2017-07-03T11:34:34.508Z
The output will be:
2017-07-03T11:34:34.508Z
If you want a different format, use a DateTimeFormatter:
DateTimeFormatter fmt = new DateTimeFormatterBuilder()
// pattern for day/hour
.appendPattern("EEE MMM dd HH:mm:ss ")
// UTC offset
.appendOffset("+HHMM", "UTC")
// year
.appendPattern(" yyyy")
// create formatter
.toFormatter(Locale.ENGLISH);
System.out.println(fmt.format(converted));
The output will be:
Mon Jul 03 11:34:34 UTC 2017
If you still need to use java.util.Date, you can easily convert from/to the new API.
In Java >= 8:
// convert your Calendar object to ZonedDateTime
converted = currentdate.toInstant()
.atZone(ZoneId.of("America/Denver"))
.withZoneSameLocal(ZoneOffset.UTC);
// converted is equals to 2017-07-03T11:34:34.508Z
// from ZonedDateTime to Date and Calendar (date will be 11:34 UTC)
Date d = Date.from(converted.toInstant());
Calendar cal = Calendar.getInstance();
cal.setTime(d);
// to get a Date that corresponds to 11:34 in Denver
Date d = Date.from(converted.withZoneSameLocal(ZoneId.of("America/Denver")).toInstant());
Calendar cal = Calendar.getInstance();
cal.setTime(d);
In Java <= 7 (ThreeTen Backport), you can use the org.threeten.bp.DateTimeUtils class:
// convert Calendar to ZonedDateTime
converted = DateTimeUtils.toInstant(currentdate)
.atZone(ZoneId.of("America/Denver"))
.withZoneSameLocal(ZoneOffset.UTC);
// converted is equals to 2017-07-03T11:34:34.508Z
// convert ZonedDateTime to Date (date will be 11:34 UTC)
Date d = DateTimeUtils.toDate(converted.toInstant());
Calendar c = DateTimeUtils.toGregorianCalendar(converted);
// to get a Date that corresponds to 11:34 in Denver
Date d = DateTimeUtils.toDate(converted.withZoneSameLocal(ZoneId.of("America/Denver")).toInstant());
Calendar c = DateTimeUtils.toGregorianCalendar(converted.withZoneSameLocal(ZoneId.of("America/Denver")));

Convert String in EST to Date in PST

I tried the below approach and searched in Web to find the solution for this but no luck : looking for the solution for converting a String in IST to PST:
String string = new Date().toString();
System.out.println(string);
SimpleDateFormat dt = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy");
dt.setTimeZone(TimeZone.getTimeZone("PST"));
Date D = dt.parse(string);
System.out.println(""+ D);
Even when I set time zone as PST, I am seeing out put in IST
here is the out put:
Tue Apr 18 18:58:09 IST 2017
Tue Apr 18 18:58:09 IST 2017
I tried another Option here I am seeing even it is showing the time in PST but I see below output it is a bit confusing:
public static Date convertFromOneTimeZoneToOhter(Date dt,String from,String to ) {
TimeZone fromTimezone =TimeZone.getTimeZone(from);//get Timezone object
TimeZone toTimezone=TimeZone.getTimeZone(to);
long fromOffset = fromTimezone.getOffset(dt.getTime());//get offset
long toOffset = toTimezone.getOffset(dt.getTime());
//calculate offset difference and calculate the actual time
long convertedTime = dt.getTime() - (fromOffset - toOffset);
Date d2 = new Date(convertedTime);
return d2;
}
OUT PUT:
Converted Date : Tue Apr 18 06:28:09 IST 2017
Can someone please help on this: I found lot of solutions on converting IST Date time to PST String but not IST/EST Date to PST Date.
As I mentioned above we can format to a String, but I am looking for an example of converting back to Date

You should look into Java 8's new Date API that handles timezones directly
// Get the current date and time
ZonedDateTime date1 = ZonedDateTime.parse("2007-12-03T10:15:30+05:30[Asia/Karachi]");
System.out.println("date1: " + date1);
ZonedDateTime zonedDateTime = ZonedDateTime.now();
System.out.println("Zoned Date Time: " + zonedDateTime);
ZoneId id = ZoneId.of("Europe/Paris");
System.out.println("ZoneId: " + id);
ZoneId currentZone = ZoneId.systemDefault();
System.out.println("CurrentZone: " + currentZone);
Prints :
date1: 2007-12-03T10:15:30+05:00[Asia/Karachi]
Zoned Date Time: 2017-04-18T09:52:09.045-04:00[America/New_York]
ZoneId: Europe/Paris
CurrentZone: America/New_York

Since some readers here will use Java 8 or later and some Java 7 or earlier, I will treat both.
I recommend you use the java.time classes introduced in Java 8 if you can:
ZoneId targetTz = ZoneId.of("America/Los_Angeles");
String string = "Tue Apr 18 18:58:09 +0300 2017";
DateTimeFormatter format = DateTimeFormatter.ofPattern("EEE MMM dd HH:mm:ss ZZZ uuuu",
Locale.ENGLISH);
ZonedDateTime sourceTime = ZonedDateTime.parse(string, format);
ZonedDateTime targetTime = sourceTime.withZoneSameInstant(targetTz);
String result = targetTime.format(format);
System.out.println(result);
This prints:
Tue Apr 18 08:58:09 -0700 2017
You said you wanted a PST date, and this is exactly what the ZonedDateTime gives you: date and time with time zone information.
In the example I am giving a zone offset, +0300 (corresponding to Israel Daylight Time) in the string. I understood that it wasn’t important to you how the time zone was given. I want to avoid the three and four letter time zone abbreviations like IST. Not only may IST mean either Irish Standard Time, Israel Standard Time or India Standard Time. I furthermore noticed that the java.time classes pick up 18:58:09 IST as 18:58:09 IDT (UTC+3) because it knows Israel is on DST on April 18; the SimpleDateFormat that I return to below takes IST more literally and interprets 18:58:09 IST as 18:58:09 +0200, which is 1 hour later in UTC.
You can use the java.time classes with Java 1.7 if you want. You can get them in the ThreeTen Backport.
If you don’t want to use java.time, the way to do it with the outdated classes from Java 1.0 and 1.1 is not that different in this case, only I cannot give you the PST date you asked for:
TimeZone targetTz = TimeZone.getTimeZone("America/Los_Angeles");
String string = "Tue Apr 18 18:58:09 +0300 2017";
SimpleDateFormat dt = new SimpleDateFormat("EEE MMM dd HH:mm:ss ZZZ yyyy", Locale.ENGLISH);
Date d = dt.parse(string);
dt.setTimeZone(targetTz);
String result = dt.format(d);
System.out.println(result);
It prints the same result as above. However, you notice there is only one Date object. A Date object cannot hold any time zone information, so if you need this, you will have to bring the targetTz object along with d. It’s a common misunderstanding that there’s supposed to be a time zone in the Date object, probably greatly helped by the fact that its toString() prints a time zone. This is always the JVM’s default time zone and doesn’t come from the Date object, though.

How to format date for use in a URL as a parameter

I am using an API to get a weather forecast up until a particular date in Java.
The requirement for passing a date as a URL parameter is that it must be in "YYYY-MM-DD'T'HH:MM:SS" format. I get input in this format from the user, then get the current system date, and then loop until the desired date. The problem lies in converting the input date string into the date format, incrementing it by one day, and then converting it back to the string format for URL parameter.
I am using the following code to do this but it is giving me incorrect results:
formatter = new SimpleDateFormat("YYYY-MM-DD'T'HH:MM:SS");
Date date1 = formatter.parse(inputtime);
System.out.println(date1);
Calendar c1 = Calendar.getInstance();
c1.setTime(date1);
c1.add(Calendar.DAY_OF_MONTH, 1); // number of days to add
inputtime = formatter.format(c1.getTime()); // dt is now the new date
System.out.println(c1.getTime());
System.out.println(inputtime);
inputtime is the input by the user. If I give "2014-04-12T00:00:00" as inputtime, date1 is then "Sun Dec 29 00:00:00 PKT 2013", c1.getTime() returns "Mon Dec 30 00:00:00 PKT 2013" and inputtime becomes then "2014-12-364T00:12:00" according to the above code block.
How can this logic error be corrected?

You should consider SimpleDateFormat date and time patterns: link
For example, something like this:
formatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");

Have a try to change your date pattern from
new SimpleDateFormat("YYYY-MM-DD'T'HH:MM:SS");
to
new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
Letter Date or Time Component Presentation Examples
y Year Year 1996; 96
M Month in year Month July; Jul; 07
D Day in year Number 189
d Day in month Number 10
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

The java.util.Date and .Calendar classes bundled with Java are notoriously troublesome. Avoid them.
That format is defined by the ISO 8601 standard. The Joda-Time library follows that standard's formats as a default for both parsing and generating strings. So does the new java.time package in Java 8.
Your string omits a time zone offset. So, you need to know and specify the time zone intended by that string. Perhaps the time zone is UTC meaning a time zone offset of zero.
A day is not always 24 hours. If you meant 24 hours rather than 1 day, call the method plusHours( 24 ).
Here is example code in Joda-Time 2.3.
String input = "2014-01-02T03:04:05";
DateTimeZone timeZone = DateTimeZone.UTC;
DateTime dateTime = new DateTime( input, timeZone );
DateTime tomorrow = dateTime.plusDays( 1 );
String outputWithOffset = tomorrow.toString();
String output = ISODateTimeFormat.dateHourMinuteSecond().print( tomorrow );

Convert string to DateFormat

i am trying to convert a string utc date to Date. by using the following code
This is My UTC String Date - 12/31/2013 8:40:00 AM
i want to convert this string to UTC Date.
static final String DATEFORMAT = "dd/MM/yyyy HH:mm:ss aa";
StringDateToDate("**12/31/2013 8:40:00 AM**");
public static Date StringDateToDate(String StrDate)
{
Date dateToReturn = null;
SimpleDateFormat dateFormat = new SimpleDateFormat(DATEFORMAT);
dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
try {
dateToReturn = dateFormat.parse(StrDate);
} catch (ParseException e) {
e.printStackTrace();
}
return dateToReturn;
}
but i am getting the wrong date in wrong format (sun jul 12 19:40:00 CDT 2015). how can i convert this utc date string to utc date. i am getting the utcdatestring from a rest webservice in XML format.

Just try this. Probably the order of your Date Format is wrong
String dtStart = "12/31/2013 8:40:00 AM";
SimpleDateFormat format = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss aa");
Date date = format.parse(dtStart);
System.out.println(date);

First your date format is wrong it should be :
static final String DATEFORMAT = "MM/dd/yyyy HH:mm:ss aa";
secondly, your input has to not have the asterixs(*) like this :
Date a = StringDateToDate("12/31/2013 8:40:00 AM");
//yea I know I should be using Log but I'm testing on java
System.out.println(a.toString());
If you really want the asterixs, do this :
String b = "**12/31/2013 8:40:00 AM**";
StringDateToDate(b.substring(2, b.length()-2));

Your input is wrong(there is no 31 month) , change it to a valid month
StringDateToDate("12/01/2013 8:40:00 AM");
to be compatible with the DateFormat
or Change your Dateformat to suit your input value
static final String DATEFORMAT = "MM/dd/yyyy HH:mm:ss aa";

Change your dateformat like this.
String DATEFORMAT = "MM/dd/yyyy HH:mm:ss aa";

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
u Day number of week Number 1
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
X Time zone ISO 8601 time zone -08; -0800; -08:00
This is the Date and Time Patterns.
String string = "January 2, 2010";
Date date = new SimpleDateFormat("MMMM d, yyyy", Locale.ENGLISH).parse(string);
System.out.println(date);

Your date format should be this in order to parse the String you have given here.
static final String DATEFORMAT = "MM/dd/yyyy HH:mm:ss aa";

And also watch out for HH. HH is Hour in day (0-23). If your input date hour is 0-11 (possibly like this since AM\PM is given and patter has aa at the end) then KK must be used instead of HH.

The result obtained is not wrong but it is what expected.
By default, parsing is lenient. With lenient parsing, the parser may use heuristics to interpret inputs that do not precisely match this object's format.
The heuristics uses the number specified for month not as months in the specified year but as months since the specified year, 31 months are 2 years and 7 months so: 01/2013 + 2years + 7 months = 07/2015.
This can be confusing so the suggestion is to set the lenient parsing to false before parsing but when pattern doesn't match something in your string a parsing exception is thrown.
public static Date StringDateToDate(String StrDate) {
Date dateToReturn = null;
SimpleDateFormat dateFormat = new SimpleDateFormat(DATEFORMAT);
dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
dateFormat.setLenient(false);
try {
dateToReturn = dateFormat.parse(StrDate);
} catch (ParseException e) {
e.printStackTrace();
}
return dateToReturn;
}

Android SimpleDateFormat, how to use it?

I am trying to use the Android SimpleDateFormat like this:
String _Date = "2010-09-29 08:45:22"
SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd");
try {
Date date = fmt.parse(_Date);
return fmt.format(date);
}
catch(ParseException pe) {
return "Date";
}
The result is good and I have: 2010-09-29
But if I change the SimpleDateFormat to
SimpleDateFormat("dd-MM-yyyy");
the problem is that I will got 03-03-0035 !!!!
Why and how to get the format like dd-MM-yyyy?

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);

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);

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.

Using the date-time API of java.util and their formatting API, SimpleDateFormat I have come across surprises several times but this is the biggest one! 😮😮😮
Given below is the illustration of what you have described in your question:
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
class Main {
public static void main(String[] args) {
System.out.println(formatDateWithPattern1("2010-09-29 08:45:22"));
System.out.println(formatDateWithPattern2("2010-09-29 08:45:22"));
}
static String formatDateWithPattern1(String strDate) {
SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd");
try {
Date date = fmt.parse(strDate);
return fmt.format(date);
} catch (ParseException pe) {
return "Date";
}
}
static String formatDateWithPattern2(String strDate) {
SimpleDateFormat fmt = new SimpleDateFormat("dd-MM-yyyy");
try {
Date date = fmt.parse(strDate);
return fmt.format(date);
} catch (ParseException pe) {
return "Date";
}
}
}
Output:
2010-09-29
03-03-0035
Surprisingly, SimpleDateFormat silently performed the parsing and formatting without raising an alarm. Anyone reading this will not have a second thought to stop using them completely and switch to the modern date-time API.
For any reason, if you have to stick to Java 6 or Java 7, you can use ThreeTen-Backport which backports most of the java.time functionality to Java 6 & 7.
If you are working for an Android project and your Android API level is still not compliant with Java-8, check Java 8+ APIs available through desugaring and How to use ThreeTenABP in Android Project.
Using the modern date-time API:
Since the pattern used in both the functions are wrong as per the input string, the parser should raise the alarm and the parsing/formatting types of the modern date-time API do it responsibly.
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeParseException;
class Main {
public static void main(String[] args) {
System.out.println(formatDateWithPattern1("2010-09-29 08:45:22"));
System.out.println(formatDateWithPattern2("2010-09-29 08:45:22"));
}
static String formatDateWithPattern1(String strDate) {
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("uuuu-MM-dd");
try {
LocalDateTime date = LocalDateTime.parse(strDate, dtf);
return dtf.format(date);
} catch (DateTimeParseException dtpe) {
return "Date";
}
}
static String formatDateWithPattern2(String strDate) {
DateTimeFormatter dtf = DateTimeFormatter.ofPattern("dd-MM-uuuu");
try {
LocalDateTime date = LocalDateTime.parse(strDate, dtf);
return dtf.format(date);
} catch (DateTimeParseException dtpe) {
return "Date";
}
}
}
Output:
Date
Date
Moral of the story
The date-time API of java.util and their formatting API, SimpleDateFormat are outdated and error-prone. Stop using them completely and switch to the modern date-time API. Learn about the modern date-time API at Trail: Date Time.
Stick to the format in your input date-time string while parsing it. If you want the output in a different format, use a differnt instance of the parser/formatter class.
Demo:
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
class Main {
public static void main(String[] args) {
String strDateTime = "2010-09-29 08:45:22";
DateTimeFormatter dtfForParsing = DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
LocalDateTime ldt = LocalDateTime.parse(strDateTime, dtfForParsing);
System.out.println(ldt);// The default format as returned by LocalDateTime#toString
// Some custom formats for output
System.out.println("########In custom formats########");
DateTimeFormatter dtfForFormatting1 = DateTimeFormatter.ofPattern("dd-MM-uuuu HH:mm:ss");
DateTimeFormatter dtfForFormatting2 = DateTimeFormatter.ofPattern("dd-MM-uuuu");
DateTimeFormatter dtfForFormatting3 = DateTimeFormatter.ofPattern("'Day: 'EEEE, 'Date: 'MMMM dd uuuu");
System.out.println(dtfForFormatting1.format(ldt));
System.out.println(dtfForFormatting2.format(ldt));
System.out.println(dtfForFormatting3.format(ldt));
System.out.println("################################");
}
}
Output:
2010-09-29T08:45:22
########In custom formats########
29-09-2010 08:45:22
29-09-2010
Day: Wednesday, Date: September 29 2010
################################

This worked for me...
#SuppressLint("SimpleDateFormat")
private void setTheDate() {
long msTime = System.currentTimeMillis();
Date curDateTime = new Date(msTime);
SimpleDateFormat formatter = new SimpleDateFormat("MM'/'dd'/'y hh:mm");
curDate = formatter.format(curDateTime);
mDateText.setText("" + curDate);
}

java.time and desugaring
I recommend that you use java.time, the modern Java date and time API, for your date work. First define a formatter for your string:
private static DateTimeFormatter formatter
= DateTimeFormatter.ofPattern("uuuu-MM-dd HH:mm:ss");
Then do:
String dateString = "2010-09-29 08:45:22";
LocalDateTime dateTime = LocalDateTime.parse(dateString, formatter);
String newString = dateTime.format(DateTimeFormatter.ISO_LOCAL_DATE);
System.out.println(newString);
Output is:
2010-09-29
I find it a good practice to parse the entire string even though we currently have no use for the time of day. That may come some other day. java.time furnishes a predefined formatter for your first output format, DateTimeFormatter.ISO_LOCAL_DATE. If you want the opposite order of day, month and year, we will need to write our own formatter for that:
private static DateTimeFormatter dateFormatter
= DateTimeFormatter.ofPattern("dd-MM-uuuu");
Then we can obtain that too:
String dmyReversed = dateTime.format(dateFormatter);
System.out.println(dmyReversed);
29-09-2010
What went wrong in your code?
the problem is that I will got 03-03-0035 !!!!
This is how confusing a SimpleDateFormat with standard settings is: With format pattern dd-MM-yyyy it parses 2010-09-29 as the 2010th day of month 9 of year 29. Year 29 AD that is. And it doesn’t disturb it that there aren’t 2010 days in September. It just keeps counting days through the following months and years and ends up five and a half years later, on 3 March year 35.
Which is just a little bit of the reason why I say: don’t use that class.
Question: Doesn’t java.time require Android API level 26?
java.time works nicely on both older and newer Android devices. It just requires at least Java 6.
In Java 8 and later and on newer Android devices (from API level 26) the modern API comes built-in.
In non-Android Java 6 and 7 get the ThreeTen Backport, the backport of the modern classes (ThreeTen for JSR 310; see the links at the bottom).
On older Android either use desugaring or the Android edition of ThreeTen Backport. It’s called ThreeTenABP. In the latter case make sure you import the date and time classes from org.threeten.bp with subpackages.
Links
Oracle tutorial: Date Time explaining how to use java.time.
Java Specification Request (JSR) 310, where java.time was first described.
ThreeTen Backport project, the backport of java.time to Java 6 and 7 (ThreeTen for JSR-310).
Java 8+ APIs available through desugaring
ThreeTenABP, Android edition of ThreeTen Backport
Question: How to use ThreeTenABP in Android Project, with a very thorough explanation.
uuuu versus yyyy in DateTimeFormatter formatting pattern codes in Java?
Wikipedia article: ISO 8601

Here is an easy example of SimpleDateFormat tried in Android Studio 3 and Java 9:
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd", Locale.US);
String strDate = sdf.format(strDate);
Note:
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd"); shows
some deprecation warning in Android Studio 3 Lint. So, add a second
parameter Locale.US to specify the Localization in date formatting.

It took a lot of efforts. I did a lot of hit and trial and finally I got the solution. I had used ""MMM"" for showing month as: JAN

If you looking for date, month and year separately
or how to use letters from answer of heloisasim
SimpleDateFormat day = new SimpleDateFormat("d");
SimpleDateFormat month = new SimpleDateFormat("M");
SimpleDateFormat year = new SimpleDateFormat("y");
Date d = new Date();
String dayS = day.format(d);
String monthS = month.format(d);
String yearS = year.format(d);

public String formatDate(String dateString) {
SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
try {
date = fmt.parse(dateString);
} catch (ParseException e) {
e.printStackTrace();
}
SimpleDateFormat fmtOut = new SimpleDateFormat("dd-MM-yyyy");
return fmtOut.format(date);
}