獲取請求地址的IP地址

public static String getIpAddr(HttpServletRequest request) throws Exception {    String ip = request.getHeader("X-Real-IP");    if(!StringUtils.isNullOrEmptyAfterTrim(ip) && !"unknown".equalsIgnoreCase(ip)) {        return ip;    } else {        ip = request.getHeader("X-Forwarded-For");        if(!StringUtils.isNullOrEmptyAfterTrim(ip) && !"unknown".equalsIgnoreCase(ip)) {            int index = ip.indexOf(44);            return index != -1?ip.substring(0, index):ip;        } else {            return request.getRemoteAddr();        }    }