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Conversion of UTC to IST time in java is working in LOCAL but not in CLOUD SERVER

I am working in date conversion in java in that i am using following code snippet to convert the UTC time to IST format.It is working properly in the local when i run it but when i deploy it in server its not converting , its displaying only the utc time itself.Is there any configuaration is needed in server side.Please help me out.
CODE SNIPPET:
DateFormat sdf = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss");
sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
String pattern = "dd-MM-yyyy HH:mm:ss";
SimpleDateFormat formatter;
formatter = new SimpleDateFormat(pattern);
try {
String formattedDate = formatter.format(utcDate);
Date ISTDate = sdf.parse(formattedDate);
String ISTDateString = formatter.format(ISTDate);
return ISTDateString;
}

Java Date objects are already/always in UTC. Time Zone is something that is applied when formatting to text. A Date cannot (should not!) be in any time zone other than UTC.
So, the entire concept of converting utcDate to ISTDate is flawed.
(BTW: Bad name. Java conventions says it should be istDate)
Now, if you want the code to return the date as text in IST time zone, then you need to request that:
DateFormat formatter = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss");
formatter.setTimeZone(TimeZone.getTimeZone("Asia/Kolkata")); // Or whatever IST is supposed to be
return formatter.format(utcDate);

Using Java 8 New API,
Instant s = Instant.parse("2019-09-28T18:12:17Z");
ZoneId.of("Asia/Kolkata");
LocalDateTime l = LocalDateTime.ofInstant(s, ZoneId.of("Asia/Kolkata"));
System.out.println(l);

How to convert an offset from GMT to the local timezone?

I have two inputs:
a date value
an integer (+8 or -3 or such) that represents the offset from GMT
Using Java, how can I convert the given date value into the corresponding date/time in the local timezone? There doesn't seem to be any timezone offset function in the Date class.
Thanks!

(If you don't want to use JodaTime) Use TimeZone with setRawOffset with code from this answer: https://stackoverflow.com/a/19378721/360211

I think you need to use the TimeZone.getAvailableIDs(rawOffsetinMiliSeconds) to get a timezone value.
Working Example:
Date now = new Date();
SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
sdf1.setTimeZone(TimeZone.getTimeZone("UTC"));
System.out.println(sdf1.format(now));
SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
sdf2.setTimeZone(TimeZone.getTimeZone((TimeZone.getAvailableIDs(5*1000*3600))[0]));
System.out.println(sdf2.format(now));

Converting a date string from a timezone to different time zone

I have a date that I get from a server formatted in EST like this
05/07/2012 16:55:55 goes month/day/year then time
if the phone is not in EST how can I convert it to the timezone the phone is in?
it would be not problem if I got the time in milliseconds but I dont
EDIT:
ok now the time is not correct when formatting
String sTOC = oNewSTMsg.getAttribute("TOC").toString();
String timezoneID = TimeZone.getDefault().getID();
DateFormat format = new SimpleDateFormat("MM/dd/yy HH:mm:ss");
format.setTimeZone(TimeZone.getTimeZone("EST"));
String newtimezoneID = TimeZone.getDefault().getID();
Date timestamp = null;
try{
timestamp = format.parse(sTOC);
format.setTimeZone(TimeZone.getDefault());
timezoneID = format.format(timestamp);
}catch(ParseException e){
}
I convert it to "EST" then format that time to the default TimeZone but the time is always off by an hour, not sure why?

Use the following code to get a UNIX timestamp:
String serverResp = "05/07/2012 16:55:55";
DateFormat format = new SimpleDateFormat("MM/dd/yy HH:mm:ss");
Date date = format.parse(serverResp);
Now you have the timestamp, which you know how to use.
Here's another question which covers conversion, in case you are curious: Android Convert Central Time to Local Time

Use the DateFormat class to parse the String into a Date. See the introduction to the API document here... http://docs.oracle.com/javase/1.5.0/docs/api/java/text/DateFormat.html
You can then create a Calendar for the Date...
Calendar cal = Calendar.getInstance().setTime(date);
And then you can change the timezone on the Calendar to a different timezone using setTimezone(). Or just get the time in milliseconds, using getTimeInMillis()
Using the Calendar, Date, and DateFormat classes should put you in the right direction.
See the Calendar documentation here... http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Calendar.html

Issue i am facing with dateFormat.parse(string)?

I have below code snippet
SimpleDateFormat dateFormat = new SimpleDateFormat(
"yyyy-MM-dd hh:mm:ss.SSS");
String processedContentDate="2012-04-10 12:53:28.033";
java.util.Date parsedDate = dateFormat.parse(processedContentDate);
java.sql.Timestamp timestamp = new java.sql.Timestamp(
parsedDate.getTime());
I get parsed date as Tue Apr 10 00:53:28 IST 2012 and timestamp as 2012-04-10 00:53:28.033 . i want to get the time exactly as 12:53:28.033(as in my original string)
not 00:53:28.033. Not getting why 12:53:28 is getting converted to 00:53:28. what should I do to get 12:53:28?
EDIT: After getting the response, I tried this small programme where current time is 14:34:38.899
but at both lines i.e at line 1 and line 2, I got below parsed date
2012-04-10 14:34:38.899
As per reply I should have got 02:34:38.899 at line 1 as date format is yyyy-MM-dd hh:mm:ss.SSS")
java.util.Date date= new java.util.Date();
String strDate=date.toString();
java.util.Date parsedDate;
java.util.Date parsedDate2;
SimpleDateFormat dateFormat = new SimpleDateFormat(
"yyyy-MM-dd hh:mm:ss.SSS");// line 1
SimpleDateFormat dateFormat2 = new SimpleDateFormat(
"yyyy-MM-dd HH:mm:ss.SSS");//line 2
try {
java.sql.Timestamp timestamp = new java.sql.Timestamp(date.getTime());
strDate=timestamp.toString();
parsedDate = dateFormat.parse(strDate);//line1
parsedDate2 = dateFormat2.parse(strDate);//line2

Define your dateFormat like that
DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
HH instead of hh. See SimpleDateFormat

Your date format must be yyyy-MM-dd HH:mm:ss.SSS.
hh is hours in am/pm, while HH is hours in a day (that's where you mistake is). See SimpleDateFormat.

As per definition of Date.toString() and Timestamp.toString, the .toString() output is always using a 24-hour clock. If you want to show the time using AM/PM, you should use the dateformatter to print the date. As you are using the same date/time as a source for both (strDate will use 14:34), when you parse the date, the SimpleDateFormat using the 12-hour clock is "lenient" and allows parsing of 14 as an hour.
If you set
dateFormat.setLenient(false);
you'll probably find that the dateFormat.parse(strDate) will fail.
To print dates, I would never rely on toString, but always use a formatter.
System.out.println(dateFormat.format(parsedDate)); // should show ...02:36...
System.out.println(dateFormat2.format(parsedDate)); // should show ...14:36...
System.out.println(dateFormat.format(parsedDate2)); // should show ...02:36...
System.out.println(dateFormat2.format(parsedDate2)); // should show ...14:36...

Try below code:
SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date date = fmt.parse("yourdate");
SimpleDateFormat fmtOut = new SimpleDateFormat("dd-MM-yyyy hh:mm a");String myDate = fmtOut.format(date);
If yourdate is 2016-06-10 12:06:43, then output will be 10-06-2016 12:06 pm.

Parse a date with the timezone "Etc/GMT"

My first attempt was:
DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
Date date = formatter.parse(string);
It throws ParseException, so I found this hack:
DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
TimeZone timeZone = TimeZone.getTimeZone("Etc/GMT");
formatter.setTimeZone(timeZone);
Date date = formatter.parse(string);
It did not work either, and now I'm stuck. It parses without problems if I just change the timezone to "GMT".
edit: An example string to parse would be "2011-11-29 10:40:24 Etc/GMT"
edit2: I would prefer not to remove timezone information completely. I am coding a server that receives the date from an external user, so perhaps other dates will have other timezones.
To be more precise: This specific date I receive is from the receipt from the apple server after making an in app purchase on an iphone app, but I could also receive dates from other sources.

Don't know if this question is still relevant to you, but if you use Joda time, this'll work:
DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss ZZZ").parseDateTime(s)
Without Joda time the following will work (bit more work though):
String s = "2011-11-29 10:40:24 Etc/GMT";
// split the input in a date and a timezone part
int lastSpaceIndex = s.lastIndexOf(' ');
String dateString = s.substring(0, lastSpaceIndex);
String timeZoneString = s.substring(lastSpaceIndex + 1);
// convert the timezone to an actual TimeZone object
// and feed that to the formatter
TimeZone zone = TimeZone.getTimeZone(timeZoneString);
DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
formatter.setTimeZone(zone);
// parse the timezoneless part
Date date = formatter.parse(dateString);

It didn't work for me either the thing is I tried setting TimeZone of SimpleDateFormatter to "Etc/GMT" and then formatted a new date here is the output:
2011-11-30 10:46:32 GMT+00:00
So Etc/GMT is being translated as GMT+00:00
If you really want to stick to parse "2011-09-02 10:26:35 Etc/GMT" then following will help too without even considering explicit Timezone change:
java.text.SimpleDateFormat isoFormat = new java.text.SimpleDateFormat("yyyy-MM-dd HH:mm:ss 'Etc/GMT'");
isoFormat.parse("2010-05-23 09:01:02 Etc/GMT");
Works fine.

Following code is working for me
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
sdf.setTimeZone(TimeZone.getTimeZone("Etc/GMT"));
try { System.out.println( sdf.parse("2011-09-02 10:26:35 Etc/GMT") );
} catch (ParseException e){
e.printStackTrace();
}