Java Calculate Number of Nanoseconds Between two LocalTime

import java.time.LocalTime;
import java.time.temporal.ChronoUnit;

public class NanosecondsBetweenLocalTimeExample {
    public static void main(String... args) {
        LocalTime startTime = LocalTime.of(10, 20, 30);
        LocalTime endTime = LocalTime.of(10, 30, 40);

        // Calculate Number of Nanoseconds Between two LocalTime
        long numberOfNanoseconds = ChronoUnit.NANOS.between(startTime, endTime);

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

Number of nanoseconds between 10:20:30 and 10:30:40 is 610000000000