code: public static String getString(final DataHandler dataHandler) throws IOException
  	{
  		if (dataHandler != null)
  		{
  			final InputStream input = dataHandler.getDataSource().getInputStream();
  			final byte[] data = ReadFileExtensions.toByteArray(input);
  			// TODO check if the output is the same...
  			return Base64.getEncoder().encodeToString(data);
  		}
  		return "";
  	}
docs: Gets the string from the given {@link DataHandler}.
  
  @param dataHandler
  the data handler
  @return the string
  @throws IOException
  Signals that an I/O exception has occurred.