JAVA Code to find distance between two GPS Coordinates

Here is a JAVA Program to find the distance between two GPS Coordinates.

       static double latitude1 = 40.6971494;
       static double latitude2 = 19.0821978;
       static double longitude1 = -74.2598702;
       static double longitude2 = 72.7410985;


 public static void findDistance()
        {

            double lon1 = Math.toRadians(longitude1);
            double lon2 = Math.toRadians(longitude2);
            double  lat1 = Math.toRadians(latitude1);
            double  lat2 = Math.toRadians(latitude2);

 
            double dlon = lon2 - lon1;
            double dlat = lat2 - lat1;
            double a = Math.pow(Math.sin(dlat / 2), 2)
                    + Math.cos(lat1) * Math.cos(lat2)
                    * Math.pow(Math.sin(dlon / 2),2);

            double c = 2 * Math.asin(Math.sqrt(a));

            // Radius of earth in kilometers. Use 3956
            // for miles
            double r = 6371;

            // calculate the result
            double distance = c * r;
       
            System.out.println("Distance in KM : "+ Math.floor(distance));
            System.out.println("Distance in Miles : "+ Math.floor(distance*.621371));
            System.out.println("Distance in Nautical Miles : "+ Math.floor(distance*.539957));

        }