实用工具类：获取客户端IP地址并判断是否为内网IP#私藏项目实操分享#

获取客户端IP地址

/**
 * 类功能描述：IP 地址工具类
 *
 * @author: 一月君言
 */
public final class IpUtil {

    private static Logger logger = LoggerFactory.getLogger(IpUtil.class);

    private static final String IP_UTILS_FLAG = ",";
    private static final String UNKNOWN = "unknown";
    private static final String LOCALHOST_IP = "0:0:0:0:0:0:0:1";
    private static final String LOCALHOST_IP1 = "127.0.0.1";

    /**
     * 获取ip地址
     *
     * @param request
     * @return
     */
    public static String getClientIpAddr(HttpServletRequest request) {
        return getClientIpAddr(request, Arrays.asList(
                "X-Original-Forwarded-For",
                "X-Forwarded-For",
                "Proxy-Client-IP",
                "WL-Proxy-Client-IP",
                "HTTP_CLIENT_IP",
                "HTTP_X_FORWARDED_FOR"
        ).iterator());
    }

    /**
     * 获取IP地址
     * <p>
     * 使用Nginx等反向代理软件， 则不能通过request.getRemoteAddr()获取IP地址
     * 如果使用了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP地址，X-Forwarded-For中第一个非unknown的有效IP字符串，则为真实IP地址
     *
     * @param request
     * @param headers
     * @return
     */
    public static String getClientIpAddr(HttpServletRequest request, Iterator<String> headers) {
        String ip = null;
        try {
            // 1. 从 header 中获取ip
            while (headers.hasNext()) {
                String tmpIp = request.getHeader(headers.next());
                if (validateIP(tmpIp)) {
                    ip = tmpIp;
                    break;
                }
            }
            //2. 兼容k8s集群获取ip
            if (StringUtils.isEmpty(ip) || UNKNOWN.equalsIgnoreCase(ip)) {
                ip = request.getRemoteAddr();
                if (LOCALHOST_IP1.equalsIgnoreCase(ip) || LOCALHOST_IP.equalsIgnoreCase(ip)) {
                    // 根据网卡取本机配置的IP
                    InetAddress inetAddress = null;
                    try {
                        inetAddress = InetAddress.getLocalHost();
                    } catch (UnknownHostException e) {
                        logger.error("getClientIpAddr error: {}", e);
                    }
                    ip = inetAddress.getHostAddress();
                }
            }
        } catch (Exception e) {
            logger.error("IpUtil ERROR ", e);
        }
        // 3. 如果使用代理， "unknown,unknown,192.168.101.1"， 则获取第一个非unknown的有效IP字符串，则为真实IP地址

        if (StringUtils.isNotEmpty(ip) && ip.contains(IP_UTILS_FLAG)) {
            String[] ipList = ip.split(IP_UTILS_FLAG);
            for (String ipTemp : ipList) {
                if (!UNKNOWN.equalsIgnoreCase(ipTemp)) {
                    ip = ipTemp;
                    break;
                }
            }
        }
        return ip;
    }

    /**
     * 检测ip 是否合法
     *
     * @param ip
     * @return
     */
    public static boolean validateIP(String ip) {
        return StringUtils.isNotEmpty(ip) && !UNKNOWN.equalsIgnoreCase(ip);
    }


}

判断IP是否是内网IP

注意：这里只是 判断 IP v4。

在项目的 pom中引入 hutool 依赖。 调用 ​​cn.hutool.core.net.NetUtil.isInnerIP(String ipAddress)​​ 即可。

<dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.7.21</version>
        </dependency>

​​cn.hutool.core.net.NetUtil​​

/**
   * 判定是否为内网IPv4<br>
   * 私有IP：
   * <pre>
   * A类 10.0.0.0-10.255.255.255
   * B类 172.16.0.0-172.31.255.255
   * C类 192.168.0.0-192.168.255.255
   * </pre>
   * 当然，还有127这个网段是环回地址
   *
   * @param ipAddress IP地址
   * @return 是否为内网IP
   * @see Ipv4Util#isInnerIP(String)
   */
  public static boolean isInnerIP(String ipAddress) {
    return Ipv4Util.isInnerIP(ipAddress);
  }

​​cn.hutool.core.net.Ipv4Util​​

/**
   * 判定是否为内网IPv4<br>
   * 私有IP：
   * <pre>
   * A类 10.0.0.0-10.255.255.255
   * B类 172.16.0.0-172.31.255.255
   * C类 192.168.0.0-192.168.255.255
   * </pre>
   * 当然，还有127这个网段是环回地址
   *
   * @param ipAddress IP地址
   * @return 是否为内网IP
   * @since 5.7.18
   */
  public static boolean isInnerIP(String ipAddress) {
    boolean isInnerIp;
    long ipNum = ipv4ToLong(ipAddress);

    long aBegin = ipv4ToLong("10.0.0.0");
    long aEnd = ipv4ToLong("10.255.255.255");

    long bBegin = ipv4ToLong("172.16.0.0");
    long bEnd = ipv4ToLong("172.31.255.255");

    long cBegin = ipv4ToLong("192.168.0.0");
    long cEnd = ipv4ToLong("192.168.255.255");

    isInnerIp = isInner(ipNum, aBegin, aEnd) || isInner(ipNum, bBegin, bEnd) || isInner(ipNum, cBegin, cEnd) || LOCAL_IP.equals(ipAddress);
    return isInnerIp;
  }