获得两个GPS点距离（数据库和java）

1.数据库方式

drop  function if exists getDistance;
DELIMITER $$  
CREATE DEFINER=`root`@`localhost` FUNCTION `getDistance`(
     lon1 double 
    ,lat1 double
    ,lon2 double
    ,lat2 double
) RETURNS double
begin
    declare d double;
    declare radius double;
    set radius = 63781.37; 
    set d = (2*ATAN2(SQRT(SIN((lat1-lat2)*PI()/180/2)   
        *SIN((lat1-lat2)*PI()/180/2)+   
        COS(lat2*PI()/180)*COS(lat1*PI()/180)   
        *SIN((lon1-lon2)*PI()/180/2)   
        *SIN((lon1-lon2)*PI()/180/2)),   
        SQRT(1-SIN((lat1-lat2)*PI()/180/2)   
        *SIN((lat1-lat2)*PI()/180/2)   
        +COS(lat2*PI()/180)*COS(lat1*PI()/180)   
        *SIN((lon1-lon2)*PI()/180/2)   
        *SIN((lon1-lon2)*PI()/180/2))))*radius;
    return d;
end
$$
DELIMITER ; 

2.java程序方式

public final class GpsHelper {
    private static final double EARTH_RADIUS = 6378.137;

    private static double rad(double d){
        return d * Math.PI / 180.0;
    }

    public static double getDistance(double lat1,double lng1, double lat2,double lng2){
        double radLat1 = rad(lat1);
        double radLat2 = rad(lat2);
        double a = radLat1 - radLat2;
        double b = rad(lng1) - rad(lng2);
        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
        s = s * EARTH_RADIUS;
        s = Math.round(s * 10000) / 10000;
        return s;
    }
}