@Test
public void testTopK()
{

    StreamSummary<String> vs = new StreamSummary<String>(3);
    String[] stream = {"X", "X", "Y", "Z", "A", "B", "C", "X", "X", "A", "C", "A", "A"};
    for (String i : stream)
    {
        vs.add(i);
    }
    List<Counter<String>> topK = vs.topK(3);
    for (Counter<String> c : topK)
    {
        assertTrue(Arrays.asList("A", "C", "X").contains(c.getItem()));
    }
}