@Test
  public void testCountSubdomains_EmptyList() {
    MemoryDocumentStorage docStorage = new MemoryDocumentStorage();
    ArrayList<Frequency> expected = new ArrayList<Frequency>();

    urlStats.runStats(docStorage);
    List<Frequency> actual = urlStats.getSubdomainFrequencies();

    TestUtils.compareFrequencyLists(expected, actual);
  }
  @Test
  public void testCountSubdomains_Tricky() {
    MemoryDocumentStorage docStorage = new MemoryDocumentStorage();
    docStorage.storeDocument("http://vision.ics.uci.edu", "");
    docStorage.storeDocument("http://vision.ics.uci.edu/", "");
    docStorage.storeDocument("http://vision.ics.uci.edu/page.php", "");
    docStorage.storeDocument("http://vision.ics.uci.edu/page.php?query", "");

    ArrayList<Frequency> expected = new ArrayList<Frequency>();
    expected.add(new Frequency("http://vision.ics.uci.edu", 3));

    urlStats.runStats(docStorage);
    List<Frequency> actual = urlStats.getSubdomainFrequencies();

    TestUtils.compareFrequencyLists(expected, actual);
  }