We could convert a date or time to a specific string format, and/or change the timezone, by using SimpleDateFormat.

Configuration

Java Compilation:
Java Runtime:

JDK 11.0.12
JRE HotSpot 11.0.12

We could convert a date or time to a specific formatted string, and/or change the timezone, by using SimpleDateFormat

First create a new SimpleDateFormat by passing the specific format. The specific format is combination of defined letters (case sensitive). e.g. y for year, M for month and d for day etc

When forming the pattern, punctuation could be used to make the patterns more desirable, e.g. yyyy-MM-dd:


SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");

Date date = new Date();

String myFormatDate = simpleDateFormat.format(date);

We can also use the setTimeZone to change the timezone of the date:


simpleDateFormat.setTimeZone(TimeZone.getTimeZone("Australia/Sydney"));

See the whole program:


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

public class MainClass {

    public static void main(String[] args) {

        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");

        Date date = new Date();

        String myFormatDate = simpleDateFormat.format(date);
        System.out.println("Formatted time: " + myFormatDate);

        simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ");

        myFormatDate = simpleDateFormat.format(date);
        System.out.println("Formatted time with seconds and mini-seconds: " + myFormatDate);

        simpleDateFormat.setTimeZone(TimeZone.getTimeZone("Australia/Sydney"));

        myFormatDate = simpleDateFormat.format(date);
        System.out.println("Formatted time with seconds and mini-seconds on Sydney timezone: " + myFormatDate);
    }
}

Sample output:


Formatted time: 2022-05-04

Formatted time with seconds and mini-seconds: 2022-05-04T14:54:17.393-0700

Formatted time with seconds and mini-seconds on Sydney timezone: 2022-05-05T07:54:17.393+1000