HTTP 获取客户端真实IP

    /**
     * 获取客户端的IP
     *
     * @param request
     * @return
     */
    public static String getRemoteAddr(HttpServletRequest request) {
        String ip = "";
        try {
            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.getRemoteAddr();
                if (ip.equals("127.0.0.1") || ip.equals("0:0:0:0:0:0:0:1")) {
                    try {
                        InetAddress inet = InetAddress.getLocalHost();
                        ip = inet.getHostAddress();
                    } catch (UnknownHostException e) {
                    }
                }
            }
            return ip.split(",")[0];
        } catch (Exception e) {
        }
        return ip;
    }

参考资料
https://www.cnblogs.com/zwdx/p/8989663.html