package com.jqyd.app;
public class GetDistance {
public static final double R = 6371004;
/**
* 根据给定的两个经纬度计算两地之间的距离，单位km
* @param lon1 经度1
* @param lat1 纬度1
* @param lon2 经度2
* @param lat2 纬度2
* @return 两地距离
*/
public static double getDistance(double lon1, double lat1, double lon2, double lat2)
{
double x = changeToRad(lon1);
double y = changeToRad(lat1);
double a = changeToRad(lon2);
double b = changeToRad(lat2);
double rad = Math.acos(Math.cos(y) * Math.cos(b) * Math.cos(x - a) + Math.sin(y) * Math.sin(b));
if (rad > Math.PI)
rad = Math.PI * 2 - rad;
return R * rad;
}
/**
* 将角度转化为弧度
* @param angle 角度
* @return 弧度
*/
public static double changeToRad(double angle)
{
return angle / 180 * Math.PI;
}
}