public static String getIpAddress(HttpServletRequest request){
        String ip = request.getHeader("x-forwarded-for"); 
        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.getHeader("HTTP_CLIENT_IP"); 
        } 
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { 
          ip = request.getHeader("HTTP_X_FORWARDED_FOR"); 
        } 
        
 
if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { 
          ip = request.getRemoteAddr(); 
        } 
        System.out.println(ip);
        return ip; 
      }

如果是多級反向代理上面方法不不行的話會出現 x-forwarded-for獲取的地址是一長串的多個ip地址

public static String getIpAddress(HttpServletRequest request){
        String ip 
 
= request.getHeader("x-forwarded-for"); 
        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.getHeader("HTTP_CLIENT_IP"); 
        } 
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { 
          ip = request.getHeader("HTTP_X_FORWARDED_FOR"); 
        } 
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) { 
          ip = request.getRemoteAddr();
          //多級反向代理
            if(ip.equals("127.0.0.1") || ip.equals("0:0:0:0:0:0:0:1")){
                //根據網絡卡取本機配置的IP
                InetAddress inet=null;
                try {
                    inet = InetAddress.getLocalHost();
                } catch (UnknownHostException e) {
                    e.printStackTrace();
                }
                ip= inet.getHostAddress();
            }

        } 
        System.out.println(ip);
        return ip; 
      }