/**
     * 得到訪問者的IP地址
     * @return ip
     * @throws Exception
     */
    public String getIp() throws Exception{
        String ip = request.getHeader("X-Forwarded-For");
        if(ip!=null){
            if(!ip.isEmpty()&&!"unKnown".equalsIgnoreCase(ip)){
                int index = ip.indexOf(",");
                if (index != -1){
                    return ip.substring(0,index);
                }else{
                    return ip;
                }
            }
        }
        ip = ServletActionContext.getRequest().getHeader("X-Real-IP");
        if(ip!=null){
            if (!ip.isEmpty()&&!"unKnown".equalsIgnoreCase(ip)){
                return ip;
            }
        }
        return  request.getRemoteAddr();
    }

    /**
     * 通過訪問的Ip地址得到mac地址
     * @param ip
     * @return mac
     */
    public String getMacByIp(String ip){
        String macAddress = "";
        try {
            java.lang.Process process = Runtime.getRuntime().exec("nbtstat -A "+ip);
            InputStreamReader ir = new InputStreamReader(process.getInputStream());
            LineNumberReader input = new LineNumberReader(ir);
            String str = "";
            while ((str=input.readLine())!=null){
                str = str.toUpperCase();
                if(str.indexOf("MAC ADDRESS")>1){
                    int start = str.indexOf("=");
                    macAddress = str.substring(start+1,str.length()).trim();
                    break;
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return  macAddress;
    }