protected String decryptString(byte[] encryptedString, byte[] iv, byte[] key)
     throws IOException, UnsupportedEncodingException {
   InputStream encryptedStream =
       cryptoHelper.decrypt(new ByteArrayInputStream(encryptedString), iv, key);
   byte[] b = IOUtils.toByteArray(encryptedStream);
   return new String(b, "utf-8");
 }
  protected DecryptedData getContentFromFileSystem(byte[] id, byte[] iv, byte[] key) {

    String[] s = getPathAndNameFromDatabase(id, iv, key);

    if (s != null) {
      try {
        FileInputStream fis = new FileInputStream(s[0]);

        DecryptedData dd = new DecryptedData();

        InputStream is = cryptoHelper.decrypt(fis, iv, key);
        String fileName = s[1];

        dd.setContent(is);
        dd.setFilaName(fileName);

        return dd;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    } else {
      return null;
    }
  }