Merge "close the opend resources when IOException happen." into main

    private static String fileToString(File file) {

        final String newline = System.lineSeparator();

        BufferedReader reader = null;

        try {

            BufferedReader reader = new BufferedReader(new FileReader(file));

            reader = new BufferedReader(new FileReader(file));

            StringBuffer sb = new StringBuffer((int) file.length() * 2);

            String line;

            while ((line = reader.readLine()) != null) {

                sb.append(line + newline);

            }

            reader.close();

            return sb.toString();

        } catch (IOException ioe) {

            Slog.e(TAG, "Couldn't read file " + file.getName());

            return null;

        } finally {

            IoUtils.closeQuietly(reader);

        }

    }