@Test
public void testPreferencesForItem() throws Exception {

  PreferenceArray prefs = model.getPreferencesForItem(456);
  assertNotNull(prefs);
  Preference pref1 = prefs.get(0);
  assertEquals(123, pref1.getUserID());
  assertEquals(456, pref1.getItemID());
  Preference pref2 = prefs.get(1);
  assertEquals(456, pref2.getUserID());
  assertEquals(456, pref2.getItemID());
  assertEquals(2, prefs.length());
}