public void testEmptyModelWithPageSize() throws Exception {
Object[] elements = new Object[0];
NewsBrowserViewModel model = new NewsBrowserViewModel(null);
model.setInput(elements, 5);
assertEquals(-1L, model.findGroup(5L));
assertEquals(-1L, model.getExpandedNews());
assertFalse(model.isFirstItemUnread());
assertTrue(model.getGroups().isEmpty());
assertEquals(0, model.getGroupSize(5L));
assertTrue(model.getNewsIds(5L).isEmpty());