SelectionTracker implements Serializable { public boolean hasSelected() { List<SelectableWrapper<T>> list = selectable.getSelectionList(); return list.stream().anyMatch(SelectableWrapper::isSelected); } SelectionTracker(@Nonnull Multiselectable<T> selectable); void selectAll(); void unselectAll(); boolean hasSelected();  }
@Test public void testHasSelected_1() throws Exception { SelectionTracker fixture = new SelectionTracker(new DataFileBrowser()); boolean result = fixture.hasSelected(); assertTrue(!result); }