由於使用了nginx反向代理，所在使用普通的ip獲取方式，獲取到的ip很可能是nginx的ip地址，所以為了解決這個問題，在Linux Nginx 配置（二）中，我已經進行了真實IP的配置，接下來，我們在程式碼中使用以下程式碼即可

public static String getIpAddr(HttpServletRequest request) {
        String unknown = "unknown";
        String ip = request.getHeader("X-real-ip");// 先從nginx自定義配置獲取
        if (ip == null || ip.length() == 0 || unknown.equalsIgnoreCase(ip)) {
            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;
    }