• Java对关于两个地点的根据经纬度算出后排序


    /**
         * 查询收货地址列表
         * 
         * @param request
         * @param wechatId
         * @return
         */
        @RequestMapping("/weixin/address/queryRecentlyAddress")
        public AddressVo queryRecentlyAddress(HttpServletRequest request, Integer wechatId, AddressVo vo) {
            String openId = OauthUtil.getInstance().getOpenId(request, String.valueOf(wechatId));
            // 查询收货地址
            Map<String, Object> map = new HashMap<String, Object>();
            String nowLng = (String) request.getAttribute("Lng");
            String nowLat = (String) request.getAttribute("Lat");
            
            map.put("openId", openId);
            List<AddressVo> aList = addressService.queryList(map);
    //TreeMap具有更具key做自动排序的功能,默认为正序即从小到大 Map
    <Double,AddressVo> addressMap=new TreeMap<Double,AddressVo>(); for(AddressVo address:aList){ String latitude = address.getLatitude(); String longitude = address.getLongitude(); double distance = Distance(nowLng,nowLat,latitude,longitude); addressMap.put(distance,address); } AddressVo addressVo = addressMap.get(0); return addressVo; }

    根据两个点的经纬度算出两个点之间的距离

    //根据两个地点的经纬度,计算两的距离

          private static final double EARTH_RADIUS = 6378.137;

    
    

          private static double rad(double d){
                          return d * Math.PI / 180.0;
               }


    public double Distance(String nowLng, String nowLat, String latitude, String longitude) { double long1; double lat1; double long2; double lat2; double a, b, sa2, sb2,d = 0; try { long1 = Double.valueOf(nowLng); lat1 = Double.valueOf(nowLat); long2 = Double.valueOf(latitude); lat2 = Double.valueOf(longitude); 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)); } catch (Exception e) { e.printStackTrace(); } return d; }
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  • 原文地址:https://www.cnblogs.com/flytogalaxy/p/6992244.html
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