Hope this might be useful to you.
Write File:
private void writeToFile(String data,Context context) { try { OutputStreamWriter outputStreamWriter = new OutputStreamWriter(context.openFileOutput("config.txt", Context.MODE_PRIVATE)); outputStreamWriter.write(data); outputStreamWriter.close(); } catch (IOException e) { Log.e("Exception", "File write failed: " + e.toString()); } } Read File:
private String readFromFile(Context context) { String ret = ""; try { InputStream inputStream = context.openFileInput("config.txt"); if ( inputStream != null ) { InputStreamReader inputStreamReader = new InputStreamReader(inputStream); BufferedReader bufferedReader = new BufferedReader(inputStreamReader); String receiveString = ""; StringBuilder stringBuilder = new StringBuilder(); while ( (receiveString = bufferedReader.readLine()) != null ) { stringBuilder.append("\n").append(receiveString); } inputStream.close(); ret = stringBuilder.toString(); } } catch (FileNotFoundException e) { Log.e("login activity", "File not found: " + e.toString()); } catch (IOException e) { Log.e("login activity", "Can not read file: " + e.toString()); } return ret; } 
