public static double dist(double long1, double lat1, double long2, double lat2) { double R = 6371; // earth radius in km double long_diff = Math.toRadians(long2 - long1); double lat_diff = Math.toRadians(lat2 - lat1); lat1 = Math.toRadians(lat1); lat2 = Math.toRadians(lat2); double temp1 = Math.sin(lat_diff / 2) * Math.sin(lat_diff / 2) + Math.sin(long_diff / 2) * Math.sin(long_diff / 2) * Math.cos(lat1) * Math.cos(lat2); return 2 * R * Math.asin(Math.sqrt(temp1)); }