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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));

How can I format Date with Locale in Android

I am using SimpleDateFormat to format my date "dd Mmm yyy" format but I want Mmm to be translated to Malay. I am using below code to do so but unable to get the expected result.
SimpleDateFormat sdf = new SimpleDateFormat(format,new Locale("ms","MY"));
return sdf.format(date);

You Should Try This Way to format locale date:
DateFormat f = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT, Locale.getDefault());
String formattedDate = f.format(new Date());
System.out.println("Date: " + formattedDate);
I Hope this will work. Reference link: Localized date format in Java

I had not set new Locale constructor properly to handle Malay language support.
String format = "MMM dd yyyy"
SimpleDateFormat sdf = new SimpleDateFormat(format, new Locale("ms","MY","MY"));
return sdf.format(date);

java.time
You are using old date-time classes that have proven to be poorly designed, confusing, and troublesome. They have been supplanted by the java.time classes built into Java 8 and later. Defined by JSR 310. Much of that functionality has been back-ported to Java 6 & 7 in the ThreeTen-Backport project and further adapted to Android in the ThreeTenABP project.
If you have a java.util.Date object, convert it to an Instant object, a moment on the timeline in UTC with a resolution of nanoseconds. New methods have been added to the old classes to facilitate conversion.
Instant instant = myJavaUtilDate.toInstant();
Or get the current moment. In Java 8, the current moment is captured only with millisecond resolution, despite the Instant class’ capacity for nanoseconds. In Java 9, the current moment is captured with up to nanosecond resolution (depending on your computer hardware clock capability).
Instant instant = Instant.now();
Apply a time zone for the locality whose wall-clock time you want to see. This is important even for a date-only value as the date varies around the world at any given moment. A new day dawns earlier in the east.
I choose a New Zealand time zone arbitrarily, for demonstration. Apply a ZoneId to get a ZonedDateTime object.
Use proper time zone names, never the 3-4 letter codes you see in the media such as IST or EST. Such codes are not standardized nor even unique.
ZoneId zoneId = ZoneId.of( "Pacific/Auckland" );
ZonedDateTime zdt = ZonedDateTime.ofInstant( instant , zoneId );
The time zone has nothing to do with localization into a human language such as Malay. A Locale handles that, as well as defining cultural norms to use for issues such as ordering of the elements or using period vs comma.
My example assumes you were correct in specifying the language and country/culture codes.
Locale locale = new Locale( "ms" , "MY" );
The java.time.format package has classes that can automatically localize when generating a String to represent a java.time value.
DateTimeFormatter formatter = DateTimeFormatter.ofLocalizedDate( FormatStyle.MEDIUM );
When defining a formatter, remember to specify the Locale. If omitted, your JVM’s current default Locale will be applied implicitly. That default can change at any moment, even during runtime! So better to be always be explicit.
formatter = formatter.withLocale( locale );
String output = zdt.format( formatter );
23 Mei 2016
By comparison when using Locale.US:
May 23, 2016
And when using Locale.CANADA_FRENCH:
2016-05-23

I am not sure if below code works for you, its written in Scala its almost same in Java.
val malaysia = new Locale("ms","MY","MY")
val cal = Calendar.getInstance(malaysia)
val df = DateFormat.getDateTimeInstance(DateFormat.FULL, DateFormat.FULL, malaysia)
println(df.format(cal.getTime()))
results from above code is
Isnin 23 Mei 2016 9:55:44 AM IST

You need to do this way;
Edit 1:
DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT, new Locale("ms","MY"));
String formattedDate = dateFormat.format(new Date());
Hope this would help you.

This code solved my problem and get the result in Bengali.
val local = Locale("bn")
val dateFormat = DateFormat.getDateInstance(DateFormat.FULL, local)
val stringDate = dateFormat.format(date)
Log.e("", stringDate)
And the output is:
মঙ্গলবার, ২৩ ফেব্রুয়ারী, ২০২১

if you want your date to be formatted to device locale then use the below code
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
Date newDate = format.parse(strDate2);
long milliDate = newDate.getTime()+getCurrentTimezoneOffset();
Calendar cal = Calendar.getInstance();
cal.setTimeInMillis(milliDate);
return format.format(cal.getTime());

Android - Convert a date to the date format of the device

How do you convert a date to the date format of the device? For example, I have following date: 02/11/2011 (mm/dd/yyyy). How to convert it to the format of the device?

DateFormat has the static methods getDateTimeInstance, getTimeInstance and getDateInstance that are already localized

You might want to consider storing your dates in a more locale-agnostic way as milliseconds.
Then you can use DateFormat.getDateFormat() like this:
dateTextView.setText(DateFormat.getDateFormat(getActivity()).format(new Date(millis)));
According to the documentation for getDateFormat():
Returns a DateFormat object that can format the date in short form (such as 12/31/1999) according to the current locale and the user's date-order preference.

Use SimpleDateFormat to convert a Date into required format.
See this link for more details..
SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyyy");
String formattedDate = format.format(yourdate);

Getting timezone on android with respect to GMT

I want to get the timezone on an android device with respect to UTC. For example, if I'm in PST timezone, then I want it in this format: "-0800". Is it possible?

This snippet gives me PST timezone represented as "-0800", which is UTC representation for PST. It was just a matter of formatting. Thanks to SimpleDateFormat class.
Calendar cal = Calendar.getInstance(Locale.getDefault()); String
timezoneStr = new SimpleDateFormat("Z").format(cal.getTime());

Get time of different Time zones on selection of time from time picker

I have an issue of converting selected hours and minutes to different time zones of countries.
Supposing if i select 10 am in India then i want to know at 10 am in india what will be the time in USA/New york and Tokyo.and Vice versa.
Any help is appreciable...
Thank you

please find the sollution below :
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy hh:mma");
TimeZone timezone = TimeZone.getDefault();
TimeZone utcTimeZone = TimeZone.getTimeZone("UTC");
Date d = new Date();
sdf.setTimeZone(timezone);
String strtime = sdf.format(d);
Log.e("str time gmt ",strtime);
sdf.setTimeZone(utcTimeZone);
strtime = sdf.format(d);
Log.e("str time utc ",strtime);
i think this will solve your problem

You can probably use Joda Time - Java date and time API. You can get the DateTimeZone depending on the Canonical ID defined in the Joda Time,
DateTimeZone zone = DateTimeZone.forID("Asia/Kolkata");
Joda Time has a complete list of Canonical ID from where you can get TimeZone depending on the Canonical ID.
So, if you want to get the local time in New York at this very moment, you would do the following
// get current moment in default time zone
DateTime dt = new DateTime();
// translate to New York local time
DateTime dtNewYork = dt.withZone(DateTimeZone.forID("America/New_York"));
For getting more idea you can refer Changing TimeZone

Try using Joda-Time library
check the org.joda.time.DateTimeZone class
Here is the API documentation for the same.

you can also get it using , Here no external API is needed
DateFormat format = new SimpleDateFormat("MMMMM d, yyyy, h:mm a");
TimeZone utc = TimeZone.getTimeZone("America/New_York");
System.out.println(utc.getID());
GregorianCalendar gc = new GregorianCalendar(utc);
Date now = gc.getTime();
System.out.println(format.format(now));
you can see more time zone on this Link
Output
America/New_York
December 29, 2012, 11:04 AM
If you don't know city name then you can also use it by Zone name as follow
DateFormat format = new SimpleDateFormat("MMMMM d, yyyy, h:mm a");
TimeZone cst = TimeZone.getTimeZone("US/Eastern");
System.out.println(cst.getID());
GregorianCalendar gc = new GregorianCalendar(cst);
Date now = gc.getTime();
format.setTimeZone(cst);
System.out.println(format.format(now))
Output
US/Eastern
December 29, 2012, 12:38 AM

Not really sure about the solution I'm going to provide but I think you can try it. GMT (Greenwich Mean Time) is a standard. I think you can keep it as a base and calculate the desired time. GMT standard is easily available too.
For example: While installing an OS like Windows XP or Windows 7, we select the time from a drop down menu. My point is, keeping this as the base, you can find the difference between the time zones in NY-US and Tokyo-Japan or vice versa as you desire it.
Hope this helps.