获取MAC地址

    private String getMACAddress() throws Exception {
        InetAddress ia = InetAddress.getLocalHost();
        byte[] mac = NetworkInterface.getByInetAddress(ia).getHardwareAddress();
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < mac.length; i++) {
            if (i != 0) {
                sb.append("-");
            }
            String s = Integer.toHexString(mac[i] & 0xFF);
            sb.append(s.length() == 1 ? 0 + s : s);
        }
        return sb.toString();
    }