sclass ConceptsComboBox extends JComboBox { Concepts concepts; Class conceptClass; AWTOnConceptChanges updater; *(Concepts *concepts, Class *conceptClass) { updateItems(); updater = new AWTOnConceptChanges(concepts, this, l0 updateItems); updater.install(); } void updateItems { setComboBoxItems_notifyListeners(this, sortTheList(asList(freshList()))); } swappable Cl freshList() { ret main list(concepts, conceptClass); } swappable L sortTheList(L l) { ret sortConceptsByID(l); } }