Unclear Question
Your question could be better written. You should try to narrow it down to a very specify example. You don't even specify the milliseconds value under discussion.
Server Time
Servers should almost always be set to a UTC/GMT time zone without Daylight Saving Time. On some systems such as Mac OS X, that is difficult. In that case, set time zone of machine to "Atlantic/Reykjavik" because Iceland stays on UTC/GMT year-round without any Daylight Saving Time nonsense.
Avoid java.util.Date
The java.util.Date & .Calendar classes bundled with Java are notoriously troublesome.
One of the pain points is that while a Date has no time zone assigned, its toString method uses the default time zone in rendering the string. So to the naïve programmer it seems like Date has a time zone when it does not.
Use either the Joda-Time library or the new java.time.* classes bundled with Java 8. Search StackOverflow for many examples of both.
Think Globally, Present Locally
Most of your business logic and your database storage should all be done in UTC/GMT (no time zone offset). A competent database such as Postgres will do so by default.
Only switch to a time zone for presentation to a user, as a general rule.
Time Zone
Always specify a time zone. Do not rely on default time zones as that causes surprises in production or any time machines change their time zone.
Avoid the three letter codes, as they are neither standardized nor unique. Use proper time zone names.
Look up your time zone names in a list like this one (slightly outdated, read details). Your mention of "India/Kolkata" in your question is, I believe, incorrect. Should be "Asia/Kolkata".
ISO 8601
If you must serialize, use only the ISO 8601 format. This format is human-readable, unambiguous, and clearly defined.
Example for India time zone: 2014-01-19T12:38:31+05:30
Example for UTC/GMT "Zulu": 2013-11-22T18:28.023Z
java.sql.* Classes
Use the java.sql.* classes for communicating to your database via JDBC.
You construct a java.sql.Timestamp object by passing the milliseconds since 1970 began. In Joda-Time, call getMillis to obtain a value to pass.
Avoid Milliseconds
Generally, I prefer to avoid dealing with milliseconds for tracking time. People tend to get into trouble since some systems track time from an epoch in seconds, milliseconds, or nanoseconds. Furthermore, there are many epochs in use, not always the Unix-style of first day of 1970.
I try to pass around either:
Example Code
But if you are sure your milliseconds value represents the true number of milliseconds since the first day of 1970 in UTC/GMT, then use this kind of code with Joda-Time. Note the 'L' flagging the number as a long integer.
DateTime dateTime = new DateTime( 1390276603054L );
DateTime dateTimeSpain = dateTime.toDateTime( DateTimeZone.forID( "Europe/Madrid" ) );
DateTime dateTimeIndia = dateTime.toDateTime( DateTimeZone.forID( "Asia/Kolkata" ) );
DateTime dateTimeUtcGmt = dateTime.toDateTime( DateTimeZone.UTC );
// For database.
java.sql.Timestamp timestamp = new java.sql.Timestamp( dateTimeSpain.getMillis() );
Dump to console…
System.out.println( "dateTime (default time zone): " + dateTime );
System.out.println( "dateTimeSpain: " + dateTimeSpain );
System.out.println( "dateTimeIndia: " + dateTimeIndia );
System.out.println( "dateTimeUtcGmt: " + dateTimeUtcGmt );
System.out.println( "timestamp: " + timestamp ); // "toString" uses default time zone.
When run…
dateTime (default time zone): 2014-01-20T19:56:43.054-08:00
dateTimeSpain: 2014-01-21T04:56:43.054+01:00
dateTimeIndia: 2014-01-21T09:26:43.054+05:30
dateTimeUtcGmt: 2014-01-21T03:56:43.054Z
timestamp: 2014-01-20 19:56:43.054
About java.time
The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.
The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.
You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.
