Java Calculate Number of Milliseconds Between Two Calendar

import java.util.Calendar;

public class DateUtil {

    /**
     * This method to get number of milliseconds between two Calendar objects.
     * @param start the start Calendar object
     * @param end the end Calendar object
     * @return the number of milliseconds between start and end Calendar.
     */
    public static long getNumberOfMillisecondsBetween(Calendar start, Calendar end) {
        long numberOfMilliseconds = end.getTimeInMillis() - start.getTimeInMillis();
        return numberOfMilliseconds;
    }

}

import java.util.Calendar;
import java.util.GregorianCalendar;

public class NumberOfMillisecondsBetweenCalendarExample {
    public static void main(String... args) {
        Calendar start = new GregorianCalendar(2022, Calendar.JULY, 1, 8, 10, 0);
        Calendar end = new GregorianCalendar(2022, Calendar.JULY, 1, 8, 11, 0);

        // Calculate Number of Milliseconds Between Two Calendar objects
        long numberOfMilliseconds = DateUtil.getNumberOfMillisecondsBetween(start, end);

        System.out.println("Start Date: " + start.getTime());
        System.out.println("End Date: " + end.getTime());
        System.out.println("Number of milliseconds: " + numberOfMilliseconds);
    }
}

Start Date: Fri Jul 01 08:10:00 ICT 2022
End Date: Fri Jul 01 08:11:00 ICT 2022
Number of milliseconds: 60000