[JAVA] 클라이언트 실제 접속 IP 구하기

String ip = request.getHeader("X-FORWARDED-FOR");

if (ip == null) {
   ip = request.getHeader("PROXY-CLIENT-IP");
}
if (ip == null) {
   ip = request.getHeader("WL-PROXY-CLIENT-IP");
}
if (ip == null) {
   ip = request.getHeader("HTTP_CLIENT_IP");
}
if (ip == null) {
   ip = request.getHeader("HTTP_X_FORWARDED_FOR");
}
if (ip == null) {
   ip = request.getRemoteAddr();
}
return ip;

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();  
        }