boolean (List<? extends Pair<String, Icon>> newData) { final JComboBox<Pair<String, Icon>> comboBox = getComponent(); final int size = comboBox.getItemCount(); final List<Pair<String, Icon>> oldData = new ArrayList<>(size); for (int i = 0; i < size; i++) { oldData.add(comboBox.getItemAt(i)); } if (myNullable) { final LinkedList<Pair<String, Icon>> list = new LinkedList<>(newData); list.addFirst(EMPTY); newData = list; } return !newData.equals(oldData); }