java根据经纬度坐标计算两点的距离算法

/**
* Created by yuliang on 2015/3/20.
*/
public class LocationUtils {
private static double EARTH_RADIUS = 6378.137;

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

/**
* 通过经纬度获取距离(单位：米)
* @param lat1
* @param lng1
* @param lat2
* @param lng2
* @return
*/
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 * 10000d) / 10000d;
s = s*1000;
return s;
}
}