取两个地图坐标之间的距离

/*****
* 取两坐标之间的距离
*****/
public class GetDistance {
private static double EARTH_RADIUS = 6378.137;//地球半径
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*1000) / 10000;//米
return s;
}
}