public static String getIpAddr(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();
  }
  return ip;
}