geohash算法二种实现方式

古城微笑少年丶 2023-06-18 08:53 3阅读 0赞

**第一种、根据经纬度进行计算，采用java编写**

package com.xxxx.sentinel.utils;
    
    import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    
    /** * @author nick */
    public class GeoHash { 
    
    
        public static final double  MINLAT = -90;
    
        public static final double  MAXLAT = 90;
    
        public static final double  MINLNG = -180;
    
        public static final double  MAXLNG = 180;
    
        public static final int ORIGINPRECISION = 30;
    
        //经纬度二分法
        private static List<Integer> latLng(double latAndLng, double min, double max) { 
            List<Integer> lngAndLatList = new ArrayList();
            if (latAndLng < min || latAndLng > max) { 
                return null;
            }
            if (ORIGINPRECISION < 1) { 
                return null;
            }
            for (int i = 0; i < ORIGINPRECISION; i++) { 
                double mid = (min + max) / 2.0;
                if (latAndLng > mid) { 
                    lngAndLatList.add(1);
                    min = mid;
                } else { 
                    lngAndLatList.add(0);
                    max = mid;
                }
            }
            return lngAndLatList;
        }
    
        public static void main(String[] args) { 
            //latLng(31.1688749, 121.3975184);
            //将经纬度转成二分法
            System.out.println(latLng(31.1688749,MINLAT,MAXLAT));
            System.out.println(latLng(121.3975184,MINLNG,MAXLNG));
            //合并经纬度
            System.out.println(listToString(latLng(121.3975184,MINLNG,MAXLNG),latLng(31.1688749,MINLAT,MAXLAT)));
            //二进制转成十进制,5个一组
            System.out.println(twoTurnTen(listToString(latLng(121.3975184,MINLNG,MAXLNG),latLng(31.1688749,MINLAT,MAXLAT))));
            //base32 映射
            System.out.println(baseCode(twoTurnTen(listToString(latLng(121.3975184,MINLNG,MAXLNG),latLng(31.1688749,MINLAT,MAXLAT)))));
        }
    
        //偶数位放经度，奇数位放纬度
        public static StringBuffer listToString(List<Integer> lngList, List<Integer> latList){ 
            StringBuffer latAndLng = new StringBuffer();
            for (int i = 0; i < ORIGINPRECISION; i++) { 
                latAndLng.append(lngList.get(i) * lngList.get(i));
                latAndLng.append(latList.get(i) * latList.get(i));
            }
            return latAndLng;
        }
    
    
    
        //二进制转成十进制,5个一组
        public static List<Integer> twoTurnTen(StringBuffer latAndLng){ 
            List<Integer> code =new ArrayList<>();
            int z = 0;
            for(int i=0;i<latAndLng.length() / 5;i++){ 
                String a = latAndLng.substring(z,z+5);
                code.add(Integer.parseInt(a, 2));
                z = z+5;
            }
            return code;
        }
    
    
         //base32 映射
         public static StringBuffer baseCode(List<Integer> code){ 
             Map<Integer,String> map = new HashMap<>(32);
             map.put(0, "0");
             map.put(1, "1");
             map.put(2, "2");
             map.put(3, "3");
             map.put(4, "4");
             map.put(5, "5");
             map.put(6, "6");
             map.put(7, "7");
             map.put(8, "8");
             map.put(9, "9");
             map.put(10, "b");
             map.put(11, "c");
             map.put(12, "d");
             map.put(13, "e");
             map.put(14, "f");
             map.put(15, "g");
             map.put(16, "h");
             map.put(17, "j");
             map.put(18, "k");
             map.put(19, "m");
             map.put(20, "n");
             map.put(21, "p");
             map.put(22, "q");
             map.put(23, "r");
             map.put(24, "s");
             map.put(25, "t");
             map.put(26, "u");
             map.put(27, "v");
             map.put(28, "w");
             map.put(29, "x");
             map.put(30, "y");
             map.put(31, "z");
             StringBuffer stringBuffer = new StringBuffer();
             for (Integer codes:code) { 
                  if(map.keySet().contains(codes)){ 
                      stringBuffer.append(map.get(codes));
                  }
             }
             return stringBuffer;
         }
    }

**第二种、根据redis的GEO实现**

package com.xxxx.sentinel.utils;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.autoconfigure.data.redis.RedisProperties;
    import org.springframework.data.geo.Point;
    import org.springframework.data.redis.core.RedisTemplate;
    import org.springframework.data.redis.core.StringRedisTemplate;
    
    import java.util.List;
    
    /** * @author nick */
    public class GeoHashRedis { 
        
        //################################
        // Springboot redis 实现
        //###############################
    
        @Autowired
        //操作k-v都是字符串的
        StringRedisTemplate stringRedisTemplate;
    
        /*@Autowired RedisTemplate redisTemplate; //k-v都是对象的*/
    
        @Autowired
        RedisTemplate<Object, Object> redisTemplate;
    
        //geoadd 添加地理位置
        private void geoadd(double lat,double lng){ 
            stringRedisTemplate.opsForGeo().add("geoTest",new Point(31.1688749, 121.3975184),"xxxx");
        }
        //geopos 查看位置信息
        private void geopos(){ 
            List<Point> position = stringRedisTemplate.opsForGeo().position("genoTest", "xxxx");
            System.out.println(position);
        }
        //geodist 计算距离
        private void geodist(){ 
    
        }
        //georadis 查看以某一点为中心，以某长度为半径的成员信息
        private void georadis(){ 
    
        }
        //geohash计算geohash值
        private void geohash(){ 
            stringRedisTemplate.opsForGeo().hash("geoTest","xxxx");
        }
    
    
    
        //############################################################
        // jedis 实现
        //############################################################
        /** * 增加地理位置的坐标 * @param key * @param coordinate * @param memberName * @return */
        public static Long geoadd(String key, GeoCoordinate coordinate, String memberName) { 
            Jedis jedis = null;
            try { 
                jedis = jedisPool.getResource();
                return jedis.geoadd(key,coordinate.getLongitude(),coordinate.getLatitude(),memberName);
            } catch (Exception e) { 
                System.out.println(e.getMessage());
            } finally { 
                if (null != jedis)
                    jedis.close();
            }
            return null;
        }
    
        /** * 批量添加地理位置 * @param key * @param memberCoordinateMap * @return */
        public static Long geoadd(String key, Map<String, GeoCoordinate> memberCoordinateMap){ 
            RedisProperties.Jedis jedis = null;
            try { 
                jedis = jedisPool.getResource();
                return jedis.geoadd(key, memberCoordinateMap);
            } catch (Exception e) { 
                System.out.println(e.getMessage());
            } finally { 
                if (null != jedis) { 
                    jedis.close();
                }
            }
            return null;
        }
    
        /** * 根据给定地理位置坐标获取指定范围内的地理位置集合（返回匹配位置的经纬度 + 匹配位置与给定地理位置的距离 + 从近到远排序，） * @param key * @param coordinate * @param radius * @return List<GeoRadiusResponse> */
        public static List<GeoRadiusResponse> geoRadius(String key, GeoCoordinate coordinate, double radius) { 
            Jedis jedis = null;
            try { 
                jedis = jedisPool.getResource();
                return jedis.georadius(key, coordinate.getLongitude(), coordinate.getLatitude(), radius, GeoUnit.KM, GeoRadiusParam.geoRadiusParam().withDist().withCoord().sortAscending());
            } catch (Exception e) { 
                System.out.println(e.getMessage());
            } finally { 
                if (null != jedis)
                    jedis.close();
            }
            return null;
        }
    
        /** * 根据给定地理位置获取指定范围内的地理位置集合（返回匹配位置的经纬度 + 匹配位置与给定地理位置的距离 + 从近到远排序，） * @param key * @param member * @param radius * @return List<GeoRadiusResponse> */
        List<GeoRadiusResponse> georadiusByMember(String key, String member, double radius){ 
            Jedis jedis = null;
            try { 
                jedis = jedisPool.getResource();
                return jedis.georadiusByMember(key, member, radius, GeoUnit.KM, GeoRadiusParam.geoRadiusParam().withDist().withCoord().sortAscending());
            } catch (Exception e) { 
                System.out.println(e.getMessage());
            } finally { 
                if (null != jedis)
                    jedis.close();
            }
            return null;
        }
    
    
        /** * 查询两位置距离 * @param key * @param member1 * @param member2 * @param unit * @return */
        public static Double geoDist(String key, String member1, String member2, GeoUnit unit){ 
            Jedis jedis = null;
            try { 
                jedis = jedisPool.getResource();
                return jedis.geodist(key, member1, member2, unit);
            } catch (Exception e) { 
                System.out.println(e.getMessage());
            } finally { 
                if (null != jedis)
                    jedis.close();
            }
            return null;
        }
    
        /** * 可以获取某个地理位置的geohash值 * @param key * @param members * @return */
        public static List<String> geohash(String key, String... members){  
            Jedis jedis = null;
            try { 
                jedis = jedisPool.getResource();
                return jedis.geohash(key, members);
            } catch (Exception e) { 
                System.out.println(e.getMessage());
            } finally { 
                if (null != jedis)
                    jedis.close();
            }
            return null;
        }
    
        /** * 获取地理位置的坐标 * @param key * @param members * @return */
        public static List<GeoCoordinate> geopos(String key, String... members){ 
            Jedis jedis = null;
            try { 
                jedis = jedisPool.getResource();
                return jedis.geopos(key, members);
            } catch (Exception e) { 
                System.out.println(e.getMessage());
            } finally { 
                if (null != jedis) { 
                    jedis.close();
                }
            }
            return null;
        }
    }

参考:[https://zhuanlan.zhihu.com/p/90889887][https_zhuanlan.zhihu.com_p_90889887]  
参考:[https://blog.csdn.net/xiangnan10/article/details/80225929][https_blog.csdn.net_xiangnan10_article_details_80225929]

[https_zhuanlan.zhihu.com_p_90889887]: https://zhuanlan.zhihu.com/p/90889887
[https_blog.csdn.net_xiangnan10_article_details_80225929]: https://blog.csdn.net/xiangnan10/article/details/80225929