File reading not working for android

I am an android newbie and wrote this code for file handling but for some reason i am always getting back null values from the file. I also tried using readline() but got the same result. Would appreciate any help.

 @Override public void onClick(View v) { // TODO Auto-generated method stub String file = "test123"; try { OutputStream out = v.getContext().openFileOutput(file, MODE_PRIVATE); InputStream in = v.getContext().openFileInput(file); WriteFile(out); String str = ReadFile(in); Toast.makeText(v.getContext(), str, Toast.LENGTH_LONG); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }); } public static void WriteFile(OutputStream out) { OutputStreamWriter tmp = new OutputStreamWriter(out); try { for (int i = 0 ; i < 10; i++) { tmp.write(i); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static String ReadFile(InputStream in) { InputStreamReader tmp = null; String str = ""; tmp = new InputStreamReader(in); BufferedReader reader=new BufferedReader(tmp); try { for (int i = 0; i < 10; i++) { str += " " + reader.readLine(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } return str; } 

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