IP 가져오기

public class GetIP {
 
    private static final String[] IP_HEADER_CANDIDATES = { 
            "X-Forwarded-For",
            "Proxy-Client-IP",
            "WL-Proxy-Client-IP",
            "HTTP_X_FORWARDED_FOR",
            "HTTP_X_FORWARDED",
            "HTTP_X_CLUSTER_CLIENT_IP",
            "HTTP_CLIENT_IP",
            "HTTP_FORWARDED_FOR",
            "HTTP_FORWARDED",
            "HTTP_VIA",
            "REMOTE_ADDR" };
 
        public static String getClientIpAddress(HttpServletRequest request) {
            for (String header : IP_HEADER_CANDIDATES) {
                String ip = request.getHeader(header);
                if (ip != null && ip.length() != 0 && !"unknown".equalsIgnoreCase(ip)) {
                    return ip;
                }
            }
            return request.getRemoteAddr();
        }
 
}

IPv4 가 아닌 0:0:0:0:0:0:0:1 과 같이 IPv6 형식의 IP를 반환한다면 아래 글 참고 : 

http://ooz.co.kr/138