for (int i = 0; i < 9; i++) {
        try {
            final Field field = KeyEvent.class.getDeclaredField("VK_" + i);
            r.keyPress((int) field.get(KeyEvent.class));

        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }