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;}