Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;

public class Main {
    private final static double EARTH_RADIUS = 6378137.0;

    public static double gps2km(final double lat_a, final double lng_a, final double lat_b, final double lng_b) {
        if (!isGpsValid(lng_a, lat_a) || !isGpsValid(lng_b, lat_b)) {
            return -1;
        }
        final double radLat1 = (lat_a * Math.PI / 180.0);
        final double radLat2 = (lat_b * Math.PI / 180.0);
        final double a = radLat1 - radLat2;
        final double b = (lng_a - lng_b) * Math.PI / 180.0;
        final 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)));
        return s * EARTH_RADIUS;
    }

    public static boolean isGpsValid(final double longitude, final double latitude) {
        return Math.abs(latitude) > 0.001 && Math.abs(longitude) > 0.001;
    }
}