OffsetDateTime withDayOfYear() method in Java with examples

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));
    }
}

Output:

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);
        }
    }
}

Output:

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)