public void changeQuote(char newQuote) throws BadQuoteException {
		if (newQuote == quote) return; // no need to do anything.
		if (!charIsSafe(newQuote)){
			throw new BadQuoteException(newQuote + " is not a safe quote.");
		}
		updateCharacterClasses(quote, newQuote);
		// keep a record of the current quote.
		quote = newQuote;
	}