GPS座標系互轉

public class PositionUtil {
    private static double pi = 3.1415926535897932384626;
    private static double a = 6378245.0;
    private static double ee = 0.00669342162296594323;

    public static Point bd09_To_Gps84(double lat, double lng) {
        Point gcj = bd09_To_Gcj02(lat, lng);
        return gcj_To_Gps84(gcj.getLat(), gcj.getLng());
        // System.out.println(gps84);
    }

    public static void main(String[] args) {
        Point ps = PositionUtil.bd09_To_Gps84(22.559083, 113.948603);
        System.out.println(ps);
    }

    /**
     * 84 to 火星座標系 (GCJ-02)
     * 
     * World Geodetic System ==> Mars Geodetic System
     * 
     * @param lat
     * @param lon
     * @return
     */
    public static Point gps84_To_Gcj02(double lat, double lon) {
        if (outOfChina(lat, lon)) {
            return null;
        }
        double dLat = transformLat(lon - 105.0, lat - 35.0);
        double dLon = transformLon(lon - 105.0, lat - 35.0);
        double radLat = lat / 180.0 * pi;
        double magic = Math.sin(radLat);
        magic = 1 - ee * magic * magic;
        double sqrtMagic = Math.sqrt(magic);
        dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
        dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
        double mgLat = lat + dLat;
        double mgLon = lon + dLon;

        return new Point(mgLon, mgLat);
    }

    /**
     * 火星座標系 (GCJ-02) to 84
     * 
     * @param lon
     * @param lat
     * @return
     */
    public static Point gcj_To_Gps84(double lat, double lon) {
        Point gps = transform(lat, lon);
        double lontitude = lon * 2 - gps.getLng();
        double latitude = lat * 2 - gps.getLat();

        return new Point(lontitude, latitude);

    }
    /**
     * GPS轉百度
     * @param lat
     * @param lon
     * @return
     */
    public static Point gps84_To_bd09(double lat, double lon) {
        Point gcj02 = gps84_To_Gcj02(lat, lon);
        return gcj02_To_Bd09(gcj02.getLat(), gcj02.getLng());
    }

    /**
     * 火星座標系 (GCJ-02) 與百度座標系 (BD-09) 的轉換算法
     * 
     * 將 GCJ-02 座標轉換成 BD-09 座標
     * 
     * @param gg_lat
     * @param gg_lon
     */
    public static Point gcj02_To_Bd09(double gg_lat, double gg_lon) {
        double x = gg_lon, y = gg_lat;

        double z = Math.sqrt(x * x + y * y) + 0.00002 * Math.sin(y * pi);

        double theta = Math.atan2(y, x) + 0.000003 * Math.cos(x * pi);

        double bd_lon = z * Math.cos(theta) + 0.0065;

        double bd_lat = z * Math.sin(theta) + 0.006;

        return new Point(bd_lon, bd_lat);
    }

    /**
     * 火星座標系 (GCJ-02) 與百度座標系 (BD-09) 的轉換算法
     * 
     * 將 BD-09 座標轉換成GCJ-02 座標
     * 
     * @param bd_lat
     * @param bd_lon
     * @return
     */
    public static Point bd09_To_Gcj02(double bd_lat, double bd_lon) {
        double x = bd_lon - 0.0065, y = bd_lat - 0.006;

        double z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * pi);

        double theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * pi);

        double gg_lon = z * Math.cos(theta);

        double gg_lat = z * Math.sin(theta);

        return new Point(gg_lon, gg_lat);
    }

    private static boolean outOfChina(double lat, double lon) {
        if (lon < 72.004 || lon > 137.8347)
            return true;
        if (lat < 0.8293 || lat > 55.8271)
            return true;
        return false;
    }

    private static Point transform(double lat, double lon) {
        if (outOfChina(lat, lon)) {
            return new Point(lon, lat);
        }
        double dLat = transformLat(lon - 105.0, lat - 35.0);
        double dLon = transformLon(lon - 105.0, lat - 35.0);
        double radLat = lat / 180.0 * pi;
        double magic = Math.sin(radLat);
        magic = 1 - ee * magic * magic;
        double sqrtMagic = Math.sqrt(magic);
        dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * pi);
        dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * pi);
        double mgLat = lat + dLat;
        double mgLon = lon + dLon;

        return new Point(mgLon, mgLat);
    }

    private static double transformLat(double x, double y) {
        double ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * Math.sqrt(Math.abs(x));
        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(y * pi) + 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0;
        ret += (160.0 * Math.sin(y / 12.0 * pi) + 320 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0;
        return ret;
    }

    private static double transformLon(double x, double y) {
        double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * Math.sqrt(Math.abs(x));
        ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(x * pi) + 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0;
        ret += (150.0 * Math.sin(x / 12.0 * pi) + 300.0 * Math.sin(x / 30.0 * pi)) * 2.0 / 3.0;
        return ret;
    }
}