The format() method of ZonedDateTime class in Java is used to format this date-time using the specified formatter passed as parameter.This date-time will be passed to the formatter to produce a string.
Syntax:
public String format(DateTimeFormatter formatter)
Parameters: This method accepts a single parameter formatter which represents the formatter to use. This is a mandatory parameter and should not be NULL.
Return value: This method returns a String represents the formatted date-time string.
Exception: This method throws a DateTimeException if an error occurs during printing.
Below programs illustrate the format() method:
Program 1:
// Java program to demonstrate// ZonedDateTime.format() method  import java.time.*;import java.time.format.*;  public class GFG {    public static void main(String[] args)    {          // create ZonedDateTime objects        ZonedDateTime zoneddatetime            = ZonedDateTime.parse("2018-12-06T19:21:12.123+05:30[Asia/Calcutta]");          // create a formatter        DateTimeFormatter formatter = DateTimeFormatter.ISO_TIME;          // apply format()        String value = zoneddatetime.format(formatter);          // print result        System.out.println("Result: " + value);    }} |
Output:
Result: 19:21:12.123+05:30
Program 2:
// Java program to demonstrate// ZonedDateTime.format() method  import java.time.*;import java.time.format.*;  public class GFG {    public static void main(String[] args)    {          // create ZonedDateTime objects        ZonedDateTime zoneddatetime            = ZonedDateTime.parse("2018-10-25T23:12:31.123+02:00[Europe/Paris]");          // create a formatter        DateTimeFormatter formatter = DateTimeFormatter.BASIC_ISO_DATE;          // apply format()        String value = zoneddatetime.format(formatter);          // print result        System.out.println("Result: " + value);    }} |
Output:
Result: 20181025+0200
