Android上读取MAC地址的方法，兼容Android M

AndroidMacAddress.java

// hacking mac
    public static String getMacAddress(Context context) {
        String macAddress = null;
        try {
            String wifiInterfaceName = "wlan0";
            Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
            while (interfaces.hasMoreElements()) {
                NetworkInterface iF = interfaces.nextElement();
                if (iF.getName().equalsIgnoreCase(wifiInterfaceName)) {
                    byte[] addr = iF.getHardwareAddress();
                    if (addr == null || addr.length == 0) {
                        return null;
                    }

                    StringBuilder buf = new StringBuilder();
                    for (byte b : addr) {
                        buf.append(String.format("%02X:", b));
                    }
                    if (buf.length() > 0) {
                        buf.deleteCharAt(buf.length() - 1);
                    }
                    macAddress = buf.toString();
                    break;
                }
            }
        } catch (SocketException se) {
            macAddress = null;
        }

        if (TextUtils.isEmpty(macAddress)) {
            android.net.wifi.WifiManager wifi = (android.net.wifi.WifiManager) context.getSystemService(Context.WIFI_SERVICE);
            macAddress = wifi.getConnectionInfo().getMacAddress();
        }

        return macAddress;
    }