public class Mac {
    public static void main(String[] args) {
        try {
            Enumeration<NetworkInterface> enumeration = NetworkInterface.getNetworkInterfaces();
            while (enumeration.hasMoreElements()) {
                StringBuffer stringBuffer = new StringBuffer();
                NetworkInterface networkInterface = enumeration.nextElement();
                if (networkInterface != null) {
                    byte[] bytes = networkInterface.getHardwareAddress();
                    if (bytes != null) {
                        for (int i = 0; i < bytes.length; i++) {
                            if (i != 0) {
                                stringBuffer.append("-");
                            }
                            int tmp = bytes[i] & 0xff; // 字节转换为整数
                            String str = Integer.toHexString(tmp);
                            if (str.length() == 1) {
                                stringBuffer.append("0" + str);
                            } else {
                                stringBuffer.append(str);
                            }
                        }
                        String mac = stringBuffer.toString().toUpperCase();  
                        System.out.println(mac);
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

在我的开发机（Windows）上运行上面代码可以获取多个Mac地址（安装了VM有若干虚拟的），但在服务器上却只能获取到一个Mac地址，请问这是为什么呢？

我却只能获取到【XX-XX-54-B3-6B-28】这一个Mac请问为什么呢？应该一个是有线网卡，一个是无线网卡获取到两个才对，可是【XX-XX-54-B3-6B-29】却获取不到

===========================分割线============================

仍未找到问题所在，临时解决办法是Windows中使用以上代码获取所有Mac，而在Linux（CentOS 7.0）中通过读取

public class Mac {
    public static void main(String[] args) throws Exception {
        StringBuffer sb = new StringBuffer();
        try {
            String str = "cat /sys/class/net/*/address | sed -n '1p'";
            String[] cmd = new String[] { "/bin/sh", "-c", str };
            Process process = Runtime.getRuntime().exec(cmd);
            BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));
            String line;
            while ((line = br.readLine()) != null) {
                sb.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        String mac = sb.toString().replace(":", "-").toUpperCase();
    }
}