double lon1 = (Math.PI/180)*_lon1;
double lon2 = (Math.PI/180)*_lon2;
//地球半径
double R = 6378.1;
double d = Math.acos(Math.sin(lat1)*Math.sin(lat2)+Math.cos(lat1)*Math.cos(lat2)*Math.cos(lon2-lon1))*R;
return new BigDecimal(d).setScale(4,BigDecimal.ROUND_HALF_UP).doubleValue();
}
public static void main(String[] args) {
System.out.println(getDistance(45.73990, 126.553,45.73876, 126.55037));
}