OffsetDateTime withHour() method in Java with examples

The withHour() method of OffsetDateTime class in Java returns a copy of this OffsetDateTime with the hour of the day altered as specified in the parameter.

Syntax:

public OffsetDateTime withHour(int hour)

Parameter: This method accepts a single parameter hour which specifies the hour of the day to be set in the result which can range from 0 to 23.

Return Value: It returns a OffsetDateTime based on this date with the requested hour of the day and not null.

Exceptions: The program throws a DateTimeException when the hour of the day value is invalid or if the day-of-year is invalid.

Below programs illustrate the withHour() method:

Program 1:

// Java program to demonstrate the withHour() 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 hour of day
        System.out.println("Date1 after altering hour of the day: "
                           + date1.withHour(20));
    }
}

Output:

Date1: 2018-12-12T13:30:30+05:00
Date1 after altering hour of the day: 2018-12-12T20:30:30+05:00

Program 2:

// Java program to demonstrate the withHour() 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 hour of day
            System.out.println("Date1 after altering hour of the day: "
                               + date1.withHour(27));
        }
        catch (Exception e) {
            System.out.println("Exception: " + e);
        }
    }
}

Output:

Date1: 2018-12-12T13:30:30+05:00
Exception: java.time.DateTimeException:
           Invalid value for HourOfDay (valid values 0 - 23): 27

Reference: https://docs.oracle.com/javase/10/docs/api/java/time/OffsetDateTime.html#withHour(int)