How to convert a time from GMT to EST

Question

I have a Date & time "20140508063630" in (yyyyMMddHHmmss) format. I want to convert this Time into EST time zone. How can I do it? If there is any API for this conversion please let me know. Thanks in advance.

Answer 1

    try {
          DateFormat gmtFormat = new SimpleDateFormat();
          TimeZone estTime = TimeZone.getTimeZone("EST");
          gmtFormat.setTimeZone(estTime);
          SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
          sdf.setTimeZone(TimeZone.getTimeZone("GMT"));
          System.out.println("EST Time: " + gmtFormat.format(sdf.parse("20140508063630")));
        } catch (ParseException e) {
          e.printStackTrace();
        }

Answer 2

Since you have tagged your question java-time, you do deserve a java.time answer.

    String dateAndTime = "20140508063630";
    DateTimeFormatter parseFormatter = DateTimeFormatter.ofPattern("yyyyMMddHHmmss");
    ZonedDateTime coralHarbourDateTime = LocalDateTime.parse(dateAndTime, parseFormatter)
            .atOffset(ZoneOffset.UTC)
            .atZoneSameInstant(ZoneId.of("America/Coral_Harbour"));
    System.out.println(coralHarbourDateTime);

This prints

2014-05-08T01:36:30-05:00[America/Coral_Harbour]

There are a number of things to note though:

• You also tagged your question android. java.time seems to be coming to Android, but as of writing it is not on the majority of Android phones. Don’ t despair, though, get the ThreeTenABP and use the classes on Android.
• The SimpleDateFormat and TimeZone classes used in the other answers are long outdated, so if your Android app is doing any work with dates and/or times and/or time zones, I do recommend ThreeTenABP and the modern classes as the programmer friendly and the futureproof way to go.
• You asked for EST time zone and then gave us a date of May 8, which is in the summer time (DST) part of the year. First, three letter abbreviations are dangerous in being ambiguous and in this case not a full time zone, so avoid them where you can. I solved the problem by using America/Coral_Harbour since I read that this particular place uses EST all year round, no summer time. If this was not what you intended, please provide a different location. If instead I use America/Montreal, I get 2014-05-08T02:36:30-04:00[America/Montreal], for example, with time zone offset -4 instead of -5.

Furhter link: How to use ThreeTenABP in Android Project

Answer 3

Following code for convert date from one timezone to another timezone with any date format

{   String parsedDate = null;

    try {
        SimpleDateFormat dbDateFormat = new SimpleDateFormat("yyyyMMddHHmmss");
    dbDateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
        Date date = dbUtcDateFormat.parse("20140508063630");

        SimpleDateFormat userDateFormat = new SimpleDateFormat(yyyyMMddHHmmss);
        userDateFormat.setTimeZone(TimeZone.getTimeZone("EST"));
        parsedDate = userDateFormat.format(date);
    } catch (Throwable t) {
        logger.warn("Date Parse Faied : ", t);
    }

    return parsedDate;
}