The withDayOfYear() method of OffsetDateTime class in Java returns a copy of this OffsetDateTime with the year-of-month altered as specified in the parameter.
Syntax:
public OffsetDateTime withDayOfYear(int dayOfYear)
Parameter: This method accepts a single parameter dayOfYear which specifies the day-of-year to be set in the result which can range from 1 to 365-366.
Return Value: It returns a OffsetDateTime based on this date with the requested day of year and not null.
Exceptions: The program throws a DateTimeException when the day-of-year value is invalid or if the day-of-year is invalid for the month of that particular year.
Below programs illustrate the withDayOfYear() method:
Program 1:
// Java program to demonstrate the withDayOfYear() method  import java.time.OffsetDateTime;import java.time.ZonedDateTime;  public class GFG {    public static void main(String[] args)    {          // Parses the date1        OffsetDateTime date1            = OffsetDateTime                  .parse(                      "2018-12-12T13:30:30+05:00");          // Prints dates        System.out.println("Date1: " + date1);          // Changes the day of year        System.out.println("Date1 after altering day-of-year: "                           + date1.withDayOfYear(32));    }} |
Date1: 2018-12-12T13:30:30+05:00 Date1 after altering day-of-year: 2018-02-01T13:30:30+05:00
Program 2:
// Java program to demonstrate the withDayOfYear() method  import java.time.OffsetDateTime;  public class GFG {    public static void main(String[] args)    {        try {            // Parses the date1            OffsetDateTime date1                = OffsetDateTime                      .parse(                          "2018-12-12T13:30:30+05:00");              // Prints dates            System.out.println("Date1: " + date1);              // Changes the day of year            System.out.println("Date1 after altering day-of-year: "                               + date1.withDayOfYear(367));        }        catch (Exception e) {            System.out.println("Exception: " + e);        }    }} |
Date1: 2018-12-12T13:30:30+05:00
Exception: java.time.DateTimeException:
Invalid value for DayOfYear
(valid values 1 - 365/366): 367
Reference: https://docs.oracle.com/javase/10/docs/api/java/time/OffsetDateTime.html#withDayOfYear(int)
