<dependency>
   <groupId>org.lionsoul</groupId>
   <artifactId>ip2region</artifactId>
   <version>1.7.2</version>
</dependency>

@Slf4j
public class IpUtil {
 
    /**
     * 獲取IP地址
     * @param request
     * @return
     */
    public static String getIpAddr(HttpServletRequest request) {
        String ip = request.getHeader("x-forwarded-for");
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("X-Real-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        }
        if ("0:0:0:0:0:0:0:1".equals(ip)) {
            ip = "127.0.0.1";
        }
        if (ip.split(",").length > 1) {
            ip = ip.split(",")[0];
        }
        return ip;
    }
 
    /**
     * 根據(jù)IP地址獲取城市
     * @param ip
     * @return
     */
    public static String getCityInfo(String ip) throws IOException {
        // 這里能讀到這個流，但是是找不到這個文件的
        ClassPathResource classPathResource = new ClassPathResource("ip2region.db");
        // 我們新建一個文件，把流存放到這個文件，再從這個文件里面讀取數(shù)據(jù)，就可以了
        File file = new File("ip2region.db");
        FileUtils.copyInputStreamToFile(classPathResource.getInputStream(),file);
        // todo 獲取輸入流
        InputStream inputStream = new FileInputStream(file);
        try {
            int len;
            byte[] buffer = new byte[1024];
            //todo 這里的輸出記得刪除再上線
            while ((len = inputStream.read(buffer)) != -1) {
               // System.out.println(new String(buffer, 0, len));
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            // TODO 記得關(guān)閉流操作
            inputStream.close();
        }
        //查詢算法
        int algorithm = DbSearcher.BTREE_ALGORITHM; //B-tree
        try {
            DbConfig config = new DbConfig();
            DbSearcher searcher = new DbSearcher(config,file.getPath());
            Method method;
            switch ( algorithm )
            {
                case DbSearcher.BTREE_ALGORITHM:
                    method = searcher.getClass().getMethod("btreeSearch", String.class);
                    break;
                case DbSearcher.BINARY_ALGORITHM:
                    method = searcher.getClass().getMethod("binarySearch", String.class);
                    break;
                case DbSearcher.MEMORY_ALGORITYM:
                    method = searcher.getClass().getMethod("memorySearch", String.class);
                    break;
                default:
                    return null;
            }
            DataBlock dataBlock;
            if (!Util.isIpAddress(ip)) {
                log.info("Error: Invalid ip address");
                return null;
            }
            dataBlock  = (DataBlock) method.invoke(searcher, ip);
            return dataBlock.getRegion();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
 
    public static void main(String[] args) {
        try {
            // 這個ip的結(jié)果是   中國|0|香港|0|香港寬頻
            String detail = IpUtil.getCityInfo("58.176.81.30");
            System.out.println(detail);
        }catch (IOException e){
 
        }
 
    }
 
}