double lat1=50.322852;
        double lon1=3.513506;
        double lat2=50.322894;
        double lon2=3.513701;


        double e=(3.14159265358979*lat1/180);
        double f=(3.14159265358979*lon1/180);
        double g=(3.14159265358979*lat2/180);
        double h=(3.14159265358979*lon2/180);
        double ii=(Math.cos(e)*Math.cos(g)*Math.cos(f)*Math.cos(h)+Math.cos(e)*Math.sin(f)*Math.cos(g)*Math.sin(h)+Math.sin(e)*Math.sin(g));
        double jj=(Math.acos(ii));
        double k=6371*jj;

        System.out.println("km:"+k+" m:"+k*1000);