一段code备用

if(wifiManager!=null)      {          Log.e("onCreate:", "onCreate: fanxiaoli   11111111111111111111111111 ");          try          {              this.macAddress = loadFileAsString("/sys/class/net/wlan0/address")                      .toUpperCase().substring(0, 17);              Log.e("onCreate: i11111111111", macAddress);          }          catch (Exception e)          {              e.printStackTrace();          }      }

private static String loadFileAsString(String filePath) throws java.io.IOException {    StringBuffer fileData = new StringBuffer(1000);    BufferedReader reader = new BufferedReader(new FileReader(filePath));    char[] buf = new char[1024];    int numRead = 0;    while ((numRead = reader.read(buf)) != -1) {        String readData = String.valueOf(buf, 0, numRead);        fileData.append(readData);    }    reader.close();    return fileData.toString();}