@Override
    public String toString() {
        return "ListView{" + "data=" + data + ", count=" + count + '}';
    }
@Test
    void testToString() {
        List<String> data = new LinkedList<>();
        data.add("1");
        data.add("2");
        data.add("3");
        ListView<String> listView = new ListView<>();
        listView.setData(data);
        listView.setCount(data.size());
        String actual = listView.toString();
        assertEquals("ListView{data=[1, 2, 3], count=3}", actual);
    }