java中根據兩個位置的經緯度計算距離

1、代碼

 /**
   * 根據兩個位置的經緯度，來計算兩地的距離（單位爲KM）
   * 參數爲double類型
   *  long1 位置1經度
   *  lat1  位置1緯度
   *  long2 位置2經度
   *  lat2  位置2緯度
   */
 public class Distance {

    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 long1, double lat1, double long2, double lat2) {
        double a, b, d, sa2, sb2;
        lat1 = rad(lat1);
        lat2 = rad(lat2);
        a = lat1 - lat2;
        b = rad(long1 - long2);

        sa2 = Math.sin(a / 2.0);
        sb2 = Math.sin(b / 2.0);
        d = 2   * EARTH_RADIUS
                * Math.asin(Math.sqrt(sa2 * sa2 + Math.cos(lat1)
                * Math.cos(lat2) * sb2 * sb2));
        return d;
    }

    public static void main(String[] args) {
        //根據兩點間的經緯度計算距離，單位：km
        System.out.println(GetDistance(116.5542, 39.81621, 116.5539, 39.81616));
        System.out.println(GetDistance(117.1181, 36.68484, 117.01, 36.66123));
        System.out.println(GetDistance(112.9084, 28.14203, 112.9083, 28.14194));
        System.out.println(GetDistance(121.5373, 38.86827, 121.5372, 38.86832));
        System.out.println(GetDistance(20.5, 118.2, 21.1, 117.6));
        System.out.println(GetDistance(121.445140,31.177779, 121.444832,31.179313));
    }