Great Circle Distance formula in Java

 private static double EARTH_RADIUS_METERS = 6371007 ; //(GRS80)
  
public static double greatCircleDistanceMeters(double Lat1, 
                  double Long1, double Lat2, double Long2)
    {
        /*
            The Haversine formula according to Dr. Math.
            http://mathforum.org/library/drmath/view/51879.html
                
            dlon = lon2 - lon1
            dlat = lat2 - lat1
            a = (sin(dlat/2))^2 + cos(lat1) * cos(lat2) * (sin(dlon/2))^2
            c = 2 * atan2(sqrt(a), sqrt(1-a)) 
            d = R * c
                
            Where
                * dlon is the change in longitude
                * dlat is the change in latitude
                * c is the great circle distance in Radians.
                * R is the radius of a spherical Earth.
                * The locations of the two points in 
                    spherical coordinates (longitude and 
                    latitude) are lon1,lat1 and lon2, lat2.
        */
        double dDistance = Double.MIN_VALUE;
        double dLat1InRad = Lat1 * (Math.PI / 180.0);
        double dLong1InRad = Long1 * (Math.PI / 180.0);
        double dLat2InRad = Lat2 * (Math.PI / 180.0);
        double dLong2InRad = Long2 * (Math.PI / 180.0);

        double dLongitude = dLong2InRad - dLong1InRad;
        double dLatitude = dLat2InRad - dLat1InRad;

        // Intermediate result a.
        double a = Math.pow(Math.sin(dLatitude / 2.0), 2.0) + 
                   Math.cos(dLat1InRad) * Math.cos(dLat2InRad) * 
                   Math.pow(Math.sin(dLongitude / 2.0), 2.0);

        // Intermediate result c (great circle distance in Radians).
        double c = 2.0 * Math.asin(Math.sqrt(a));

        dDistance = EARTH_RADIUS_METERS * c;

        return dDistance;
    }