How to convert Java Date into Specific TimeZone format

In the last example, we learned how to convert Date to String in Java. In this example, I am converting a Java Date object from one timezone to another. We will use SimpleDateFormat class to format the Date in a specific format and we will set its timezone to print the date in a specific timezone.

package com.journaldev.util;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class DateFormatter {

	/**
	 * Utility function to convert java Date to TimeZone format
	 * @param date
	 * @param format
	 * @param timeZone
	 * @return
	 */
	public static String formatDateToString(Date date, String format,
			String timeZone) {
		// null check
		if (date == null) return null;
		// create SimpleDateFormat object with input format
		SimpleDateFormat sdf = new SimpleDateFormat(format);
		// default system timezone if passed null or empty
		if (timeZone == null || "".equalsIgnoreCase(timeZone.trim())) {
			timeZone = Calendar.getInstance().getTimeZone().getID();
		}
		// set timezone to SimpleDateFormat
		sdf.setTimeZone(TimeZone.getTimeZone(timeZone));
		// return Date in required format with timezone as String
		return sdf.format(date);
	}

	public static void main(String[] args) {
		//Test formatDateToString method
		Date date = new Date();
		System.out.println("Default Date:"+date.toString());
		System.out.println("System Date: "+formatDateToString(date, "dd MMM yyyy hh:mm:ss a", null));
		System.out.println("System Date in PST: "+formatDateToString(date, "dd MMM yyyy hh:mm:ss a", "PST"));
		System.out.println("System Date in IST: "+formatDateToString(date, "dd MMM yyyy hh:mm:ss a", "IST"));
		System.out.println("System Date in GMT: "+formatDateToString(date, "dd MMM yyyy hh:mm:ss a", "GMT"));
	}

}

Here is the output of the program:

Default Date:Wed Nov 14 21:37:01 PST 2012
System Date: 14 Nov 2012 09:37:01 PM
System Date in PST: 14 Nov 2012 09:37:01 PM
System Date in IST: 15 Nov 2012 11:07:01 AM
System Date in GMT: 15 Nov 2012 05:37:01 AM

From the output, it’s clear that my system TimeZone is PST and then it’s converting same Date object to different timezones like IST and GMT and printing it. Using my last tutorial you can again convert the returned string to a Date object. Update: Java 8 has added new Date Time API, you should check it out at Java 8 Date.