Java Calculate Number of Nanoseconds Between two LocalDateTime

import java.time.LocalDateTime;
import java.time.temporal.ChronoUnit;

public class NanosecondsBetweenLocalDateTimeExample {
    public static void main(String... args) {
        LocalDateTime start = LocalDateTime.parse("2022-07-11T08:30:00");
        LocalDateTime end = LocalDateTime.parse("2022-07-11T09:30:00");

        // Calculate Number of Nanoseconds Between two LocalDateTime
        long numberOfNanoseconds = ChronoUnit.NANOS.between(start, end);

        System.out.println(String.format("Number of nanoseconds between %s and %s is %d", start, end, numberOfNanoseconds));
    }
}

Number of nanoseconds between 2022-07-11T08:30 and 2022-07-11T09:30 is 3600000000000