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Convert indian time zone to local time

In my app I am getting time from server in API in IST timezone, I want to show time in device's local time zone.
Below is my code for this but it seems its not working.
SimpleDateFormat serverSDF = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat utcSDF = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat localSDF = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
serverSDF.setTimeZone(TimeZone.getTimeZone("Asia/Calcutta"));
utcSDF.setTimeZone(TimeZone.getTimeZone("UTC"));
localSDF.setTimeZone(TimeZone.getDefault());
Date serverDate = serverSDF.parse(dateString);
String utcDate = utcSDF.format(serverDate);
Date localDate = localSDF.parse(utcDate);
From server I am getting time "2018-02-28 16:04:12" in IST and the code above displays "Wed Feb 28 10:34:12 GMT+05:30 2018".

The other answer uses GMT+05:30, but it's much better to use a proper timezone such as Asia/Kolkata. It works now because India currently uses the +05:30 offset, but it's not guaranteed to be the same forever.
If someday the government decides to change the country's offset (which already happened in the past), your code with a hardcoded GMT+05:30 will stop working - but a code with Asia/Kolkata (and a JVM with the timezone data updated) will keep working.
But today there's a better API to manipulate dates, see here how to configure it: How to use ThreeTenABP in Android Project
This is better than SimpleDateFormat, a class known to have tons of problems: https://eyalsch.wordpress.com/2009/05/29/sdf/
With this API, the code would be:
String serverDate = "2018-02-28 16:04:12";
DateTimeFormatter fmt = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
LocalDateTime istLocalDate = LocalDateTime.parse(serverDate, fmt);
// set the date to India timezone
String output = istLocalDate.atZone(ZoneId.of("Asia/Kolkata"))
// convert to device's zone
.withZoneSameInstant(ZoneId.systemDefault())
// format
.format(fmt);
In my machine, the output is 2018-02-28 07:34:12 (it varies according to the default timezone of your environment).
Although it seems complicated to learn a new API, in this case I think it's totally worth it. The new API is much better, easier to use (once you learn the concepts), less error-prone, and fix lots of problems of the old API.
Check Oracle's tutorial to learn more about it: https://docs.oracle.com/javase/tutorial/datetime/

Update: Check this answer by #istt which uses modern Java8 date-time api.
You don't need to change format in UTC first. You can simply use:
SimpleDateFormat serverSDF = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
SimpleDateFormat localSDF = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
serverSDF.setTimeZone(TimeZone.getTimeZone("Asia/Kolkata"));
localSDF.setTimeZone(TimeZone.getDefault());
String localDate = localSDF.format(serverSDF.parse(dateString));

Create Joda datetime UTC from String

I have the following String that I would like to change to UTC:
Thu Aug 24 07:38:32 GMT+01:00 2017
I'm using Joda-Time library.
I know how to create a new Datetime eg new dateTime(DateTimeZone.UTC) but how can I create a DateTime object from the above String?
I have tried the following but get an exception. Surely there must be another way to create a DT obect without chopping the original String up? What if the external API changes how it sends my app the orignal String, my String manipulation code would fail.
DateTimeFormatter df = DateTimeFormat.forPattern("dd-MMM-YYYY HH:mm");
String strOrigTime = "Thu Aug 24 07:38:32 GMT+01:00 2017";
DateTime dt = DateTime.parse(strOrigTime, df);
Log.e(TAG, "dt after parse = " + dt.toString());
Error:
Caused by: java.lang.IllegalArgumentException: Invalid format: "Thu Aug 24 07:38:32 GMT+01:00 2017"
at org.joda.time.format.DateTimeFormatter.parseDateTime(DateTimeFormatter.java:866)
at org.joda.time.DateTime.parse(DateTime.java:144)

The format used (dd-MMM-YYYY HH:mm) means: day (dd) followed by -, followed by month (MMM), followed by -, followed by year (YYYY) and so on (check the javadoc for more details).
This format doesn't match the input string (which has day-of-week followed by month, followed by day, then hour/minute/second, etc). So the first thing is to use a format that matches the input, otherwise you'll always get "Invalid format" errors.
Another detail is that day of week and month names are in English, so you must also use a java.util.Locale to specify the language you're using to parse the input. If you don´t use a locale, the system default will be used, and it's not guaranteed to always be English (and it can also be changed, even at runtime, so it's always better to specify one).
I also had to add "GMT" as a literal and call withOffsetParsed() to make it include the offset (+01:00) in the parsed object:
DateTimeFormatter df = DateTimeFormat
// use a pattern that matches input
.forPattern("EEE MMM dd HH:mm:ss 'GMT'Z yyyy")
// use English locale for day of week and month
.withLocale(Locale.ENGLISH)
// include the offset (+01:00) in the parsed object
.withOffsetParsed();
String strOrigTime = "Thu Aug 24 07:38:32 GMT+01:00 2017";
DateTime dt = DateTime.parse(strOrigTime, df);
System.out.println(dt.toString());
The output is:
2017-08-24T07:38:32.000+01:00
Then, you can set the UTC timezone to this object:
dt = dt.withZone(DateTimeZone.UTC);
System.out.println(dt.toString());
The output will be:
2017-08-24T06:38:32.000Z
Note that withZone method preserves the same instant (both dates represent the same point in time), just the timezone used in the output is changed. But both dates are equivalent (they represent the same instant, as 07:38 in offset +01:00 is the same as 06:38 in UTC).
If you want all dates to be converted to UTC, you can also set this in the formatter:
// set UTC to the formatter
df = df.withZone(DateTimeZone.UTC);
Then you don't need to call withZone in the DateTime objects: all parsed dates will be converted to UTC.
You also told that "if the external API changes how it sends my app the orignal String, my String manipulation code would fail".
Well, if the input String changes, you'll have to change your format as well - there's no other way, Joda-Time can't just guess what's the format, you have to tell it.
If you want to parse more than one format, there's a way to create a formatter that uses lots of different patterns and try to parse each one, until one of them works (or throw exception if none works). You could do something like that:
// format 1
DateTimeFormatter f1 = DateTimeFormat
// use a pattern that matches input
.forPattern("EEE MMM dd HH:mm:ss 'GMT'Z yyyy")
// use English locale for day of week and month
.withLocale(Locale.ENGLISH)
// include the offset (+01:00) in the parsed object
.withOffsetParsed();
// format 2
DateTimeFormatter f2 = DateTimeFormat.forPattern("dd/MM/yyyy HH:mm:ss Z");
// array of all possible formats
DateTimeParser[] parsers = { f1.getParser(), f2.getParser() };
// formatter that uses all the possible formats
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
// append array of possible formats
.append(null, parsers)
// create formatter
.toFormatter().withLocale(Locale.ENGLISH).withOffsetParsed()
// set all parsed objects to UTC
.withZone(DateTimeZone.UTC);
// parse first format
System.out.println(DateTime.parse("Thu Aug 24 07:38:32 GMT+01:00 2017", formatter));
// parse second format
System.out.println(DateTime.parse("24/08/2017 07:38:32 +01:00", formatter));
Both dates will be parsed to:
2017-08-24T06:38:32.000Z
Then you can add new formats to the array, as needed.
Java new Date/Time API
Joda-Time is in maintainance mode and is being replaced by the new APIs, so I don't recommend start a new project with it. Even in joda's website it says: "Note that Joda-Time is considered to be a largely “finished” project. No major enhancements are planned. If using Java SE 8, please migrate to java.time (JSR-310).".
If you can't (or don't want to) migrate from Joda-Time to the new API, you can ignore this section.
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.
The code to parse the inputs is very similar, with minor changes in the format.
And I'm using the Instant class, because you want the output in UTC, and Instant represents a UTC instant:
// format 1
DateTimeFormatter f1 = DateTimeFormatter.ofPattern("EEE MMM dd HH:mm:ss O yyyy", Locale.ENGLISH);
// format 2
DateTimeFormatter f2 = DateTimeFormatter.ofPattern("dd/MM/yyyy HH:mm:ss XXX");
// formatter with both formats
DateTimeFormatter formatter = new DateTimeFormatterBuilder()
// add format 1
.appendOptional(f1)
// add format 2
.appendOptional(f2)
// create formatter
.toFormatter(Locale.ENGLISH);
// parse first format
System.out.println(Instant.from(formatter.parse("Thu Aug 24 07:38:32 GMT+01:00 2017")));
// parse second format
System.out.println(Instant.from(formatter.parse("24/08/2017 07:38:32 +01:00")));
This will output:
2017-08-24T06:38:32Z
2017-08-24T06:38:32Z

How to get timezone in short in android

I am trying to display a timestamp as "Sat Dec xx ww:yy:zz IST YYYY".
When i run this code snippet in android device i get result as "Sat Dec xx ww:yy:zz GMT+05:30 YYYY".
Date dd = new Date();
String s = dd.toString();
The below snippet also gives the time in GMT+05:30 format.
String timeZone =
Calendar.getInstance().getTimeZone().getDisplayName(false, TimeZone.SHORT);
TimeZone can be any of the zones as per mob. location. So hard coding doesn't make any sense.
How can i get the result in the desired format?

Use SimpleDateFormat to explicitly get "Sat Dec xx ww:yy:zz" part and "YYYY" part
Store them up in variables
get the time zone String using
String timeZone =
Calendar.getInstance().getTimeZone().getID();
then use
String.format("%s %s %s", firstPart, timeZone, yearPart);

joda-time can't read Parse dateTime string

I'm having an issue with joda-time formatting a date time string that Parse (parse.com) has stored in an sqlite table.
Sqlite creation string: "createdDate date time"
Storing parse date into table: "insert... parseObject.getCreatedAt()"
If i then use a SQLite browser to inspect the table, I see the date stored like this:
Sat Jun 15 15:44:52 PDT 2013
So going along with that, I wrote the following to convert it back into a DateTime object to give to parse as part of a query to get items that are newer than the last inserted in my table:
DateTimeFormatter format = DatetimeFormat.forPattern("yyyy'-'MM'-'dd'T'HH':'mm':'ss.SSS'Z'");
DateTime dt = formatter.parseDateTime(datahelper.getLastInsertDate(..));
The formatter is this way, because in Parse's databrowser, I can see dateTimes being stored like this:
2013-06-24T08:11:45.280Z
I get an ANR though, so I tried using the following formatter:
DateTimeFormatter format = DatetimeFormat.forPattern("EEE' 'MMM' 'dd' 'HH':'mm':'ss 'z'' 'YYYY");
DateTime dt = formatter.parseDateTime(datahelper.getLastInsertDate(..));
and I still get an ANR. The trace in eclipse shows the following:
Caused by: java.lang.IllegalArgumentException: invalid format: "Tue Jun 25 00:13:29 PDT 2013"
at org.joda.time.format.DateTimeFormatter.parseDateTime"
The second ANR trace shows:
Invalid format: "Tue Jun 25 00:13:29 PDT 2013" is malformed at "PDT
2013"
I've tried getting around that, as joda time does not parse "z" to PDT/PST, so I've put 'PDT' in my formatter to hopefully get it to work, but nothing seems to work.
Any ideas?
Edit 1: Using the accepted answer, I have a timezone formatting issue)
DateFormat originalFormat = new SimpleDateFormat("EEE MMM DDD HH:mm:ss z yyyy");
Date originaldate = originalFormat.parse(datahelper.getLastInsertdate);
Log.i("converted date: ", String.valueOf(originalDate);
Log.i("a real date: ", "String.valueOf(new Date(new Date().getTime)));
I get two outputs:
Fri Jan 25 15:14:11 PST 2013
Tue Jun 25 17:11:44 PDT 2013
why does the converted date show PST, and a standard Date shows PDT?

It seems to be a known problem Joda cannot parse Timezone names sadly. In the documentation before all the pattern syntaxes you will see this line:
The pattern syntax is mostly compatible with java.text.SimpleDateFormat - time zone names cannot be parsed and a few more symbols are supported. All ASCII letters are reserved as pattern letters, which are defined as follows:
You can see that in the documentation link here
Now the solution to your answer can be found in this answer by #BalusC located here
Hope this helps.

I think that with SQLite, because the date type is somewhat broken, the best thing to do is to store the long that you get from Date.getTime() or related Joda methods.
When you get the long from the database, re-construct your date object (e.g. new Date(long)), and then format that.
Above all, remember that (IMHO) the only sensible way to store a date is in reference to UTC, which is what you get with Date.getTime() and new Date(long) : milliseconds since Jan 1, 1970 UTC.
Once you retrieve your date, format it with whatever timezone is appropriate.

android problem with SimpleDateFormat TimeZone

Let's consider this code sample:
DateFormat sdf = SimpleDateFormat.getTimeInstance(SimpleDateFormat.LONG,
new Locale("ru", "RU"));
Date date = sdf.parse("8:13:05 PDT");
When I run this code on my desktop(java 1.6) all passes well, however on android devices I get exception, I think this is due to locale TimeZone:
java.text.ParseException: Unparseable date: 8:13:05 PDT
Why?

I don't believe UNIX can parse the PDT timezone. I'm having the same issue. It can handle PST & PST8PDT, but not PDT. I believe the recommended solution is to use PST8PDT instead.