content: package com.admin4j.spring.util;
  
  
  import javax.servlet.http.HttpServletRequest;
  import java.net.InetAddress;
  import java.net.UnknownHostException;
  import java.util.Objects;
  
  /**
   * 获取IP方法
   */
  public class IpUtils {
      public static String getIpAddr(HttpServletRequest request) {
          if (Objects.isNull(request)) {
              return "127.0.0.1";
          }
          String ip = null;
  
          // X-Forwarded-For：Squid 服务代理
          String ipAddresses = request.getHeader("X-Forwarded-For");
          if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
              // Proxy-Client-IP：apache 服务代理
              ipAddresses = request.getHeader("Proxy-Client-IP");
          }
          if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
              // WL-Proxy-Client-IP：weblogic 服务代理
              ipAddresses = request.getHeader("WL-Proxy-Client-IP");
          }
          if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
              // HTTP_CLIENT_IP：有些代理服务器
              ipAddresses = request.getHeader("HTTP_CLIENT_IP");
          }
          if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
              // X-Real-IP：nginx服务代理
              ipAddresses = request.getHeader("X-Real-IP");
          }
  
          // 有些网络通过多层代理，那么获取到的ip就会有多个，一般都是通过逗号（,）分割开来，并且第一个ip为客户端的真实IP
          if (ipAddresses != null && ipAddresses.length() != 0) {
              ip = ipAddresses.split(",")[0];
          }
  
          // 还是不能获取到，最后再通过request.getRemoteAddr();获取
          if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
              ip = request.getRemoteAddr();
          }
          return ip.equals("0:0:0:0:0:0:0:1") ? "127.0.0.1" : ip;
      }
  
      public static boolean internalIp(String ip) {
          byte[] addr = textToNumericFormatV4(ip);
          return internalIp(addr) || "127.0.0.1".equals(ip);
      }
  
      private static boolean internalIp(byte[] addr) {
          if (addr == null || addr.length < 2) {
              return true;
          }
          final byte b0 = addr[0];
          final byte b1 = addr[1];
          // 10.x.x.x/8
          final byte SECTION_1 = 0x0A;
          // 172.16.x.x/12
          final byte SECTION_2 = (byte) 0xAC;
          final byte SECTION_3 = (byte) 0x10;
          final byte SECTION_4 = (byte) 0x1F;
          // 192.168.x.x/16
          final byte SECTION_5 = (byte) 0xC0;
          final byte SECTION_6 = (byte) 0xA8;
          switch (b0) {
              case SECTION_1:
                  return true;
              case SECTION_2:
                  if (b1 >= SECTION_3 && b1 <= SECTION_4) {
                      return true;
                  }
              case SECTION_5:
                  switch (b1) {
                      case SECTION_6:
                          return true;
                  }
              default:
                  return false;
          }
      }
  
      /**
       * 将IPv4地址转换成字节
       *
       * @param text IPv4地址
       * @return byte 字节
       */
      public static byte[] textToNumericFormatV4(String text) {
          if (text.length() == 0) {
              return null;
          }
  
          byte[] bytes = new byte[4];
          String[] elements = text.split("\\.", -1);
          try {
              long l;
              int i;
              switch (elements.length) {
                  case 1:
                      l = Long.parseLong(elements[0]);
                      if ((l < 0L) || (l > 4294967295L)) {
                          return null;
                      }
                      bytes[0] = (byte) (int) (l >> 24 & 0xFF);
                      bytes[1] = (byte) (int) ((l & 0xFFFFFF) >> 16 & 0xFF);
                      bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);
                      bytes[3] = (byte) (int) (l & 0xFF);
                      break;
                  case 2:
                      l = Integer.parseInt(elements[0]);
                      if ((l < 0L) || (l > 255L)) {
                          return null;
                      }
                      bytes[0] = (byte) (int) (l & 0xFF);
                      l = Integer.parseInt(elements[1]);
                      if ((l < 0L) || (l > 16777215L)) {
                          return null;
                      }
                      bytes[1] = (byte) (int) (l >> 16 & 0xFF);
                      bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);
                      bytes[3] = (byte) (int) (l & 0xFF);
                      break;
                  case 3:
                      for (i = 0; i < 2; ++i) {
                          l = Integer.parseInt(elements[i]);
                          if ((l < 0L) || (l > 255L)) {
                              return null;
                          }
                          bytes[i] = (byte) (int) (l & 0xFF);
                      }
                      l = Integer.parseInt(elements[2]);
                      if ((l < 0L) || (l > 65535L)) {
                          return null;
                      }
                      bytes[2] = (byte) (int) (l >> 8 & 0xFF);
                      bytes[3] = (byte) (int) (l & 0xFF);
                      break;
                  case 4:
                      for (i = 0; i < 4; ++i) {
                          l = Integer.parseInt(elements[i]);
                          if ((l < 0L) || (l > 255L)) {
                              return null;
                          }
                          bytes[i] = (byte) (int) (l & 0xFF);
                      }
                      break;
                  default:
                      return null;
              }
          } catch (NumberFormatException e) {
              return null;
          }
          return bytes;
      }
  
      public static String getHostIp() {
          try {
              return InetAddress.getLocalHost().getHostAddress();
          } catch (UnknownHostException e) {
          }
          return "127.0.0.1";
      }
  
      public static String getHostName() {
          try {
              return InetAddress.getLocalHost().getHostName();
          } catch (UnknownHostException e) {
          }
          return "未知";
      }
  }