How to convert String Jul 21, 2020, 7:53:14 PM into "DD/MM/YYYY a" format in java

I have a string as "Jul 22, 2020, 11:56:51 PM" and I want to convert it into "DD/MM/YYYY a" format so that the output is 22/07/2020 11:56:51 PM.

I have tried but it gives me a time difference of 5:30 hours. I want to have the same date.

> ExportObj has a property date which is of type String.

Output I'm getting is - 07/22/2020 06:26 PM

public Class Export {

public static void main(string[] args){
        SimpleDateFormat sf = new SimpleDateFormat(user.getDateFormatWithTime());
        String id = String.valueOf(currentUser.getTimeZoneId());
        TimeZone timeZone = TimeZone.getTimeZone(id);
        sf.setTimeZone(timeZone);
        ExportObj obj = new ExportObj();
        obj.setDate(sf.format(new Date()));
        System.out.println(obj.getDate());
  }
}

You should not keep date and time as a String in your ExportObj. Just as you keep numbers in int and double variables and Boolean values in boolean variables (I hope), use proper date-time types for your dates and times. In this case a ZonedDateTime is probably best suited, but depending on circumstances and precise requirements you may consider Instant or some other class from java.time, the modern Java date and time API.

When you need to show the date and time to a user, format the date-time into an appropriate string for that purpose.

java.time

Use java.time, the modern Java date and time API, for your date and time work. For your conversion:

	DateTimeFormatter sourceFormatter = DateTimeFormatter.ofPattern("MMM d, uuuu, hh:mm:ss a", Locale.ENGLISH);
	DateTimeFormatter targetormatter = DateTimeFormatter.ofPattern("dd/MM/uuuu hh:mm:ss a", Locale.ENGLISH);
	
	String id = "Etc/UTC";
	String stringWeveGot = "Jul 22, 2020, 11:56:51 PM";
	
	ZoneId zone = ZoneId.of(id);
	ZonedDateTime dateTime = LocalDateTime.parse(stringWeveGot, sourceFormatter)
			.atZone(zone);
	
	System.out.println(dateTime);
	
	String convertedString = dateTime.format(targetormatter);
	
	System.out.println(convertedString);

Output:

> 2020-07-22T23:56:51Z[Etc/UTC]
> 22/07/2020 11:56:51 PM

As I said, put the ZonedDateTime object into your ExportObj object, not the string.

What went wrong in your code?

It’s a bit hard for me to be sure what happened when you got a time that was 5 hours 30 minutes too early since your code isn’t complete and I cannot run it. You probably applied your time zone to only one of your formatters, leaving the other one to use a different time zone, for example the default time zone of your JVM, giving rise to an unwanted conversion between those time zones. ZonedDateTime of java.time makes this situation easier to handle since contrary to the old-fashioned Date class it keeps the time zone inside the date-time object rather than in the formatters.

Link

• Oracle tutorial: Date Time explaining how to use java.time.

Run this :

public class Test {

	public static void main(String [] args) throws ParseException {

		
		final String OLD_FORMAT = "MMM dd, yyyy, hh:mm:ss a";
		final String NEW_FORMAT = "dd/MM/yyyy hh:mm:ss a";

		String oldDateString = "Jul 22, 2020, 11:56:51 PM";
		String newDateString;

		SimpleDateFormat sdf = new SimpleDateFormat(OLD_FORMAT);
		Date d = sdf.parse(oldDateString);
		sdf.applyPattern(NEW_FORMAT);
		newDateString = sdf.format(d);
		System.out.println(newDateString);
		
	}

Output :

22/07/2020 11:56:51 PM