Why "NullPointerException" when reading strings and a last string is empty?

public static void main(String[] args) throws Exception {
        //tutaj wpisz swój kod
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            String name = reader.readLine();
            if (name.equals(""))
                break;
            System.out.println(CatFactory.getCatByKey(name));
        }
    }