public @NotNull Collection<T> getItems(String prefix, boolean cached, CompletionParameters parameters) {
    if (prefix == null) {
      return Collections.emptyList();
    }

    final List<T> items = new ArrayList<>(myVariants);

    items.sort(this);
    return items;
  }
public @NotNull Collection<T> getItems(String prefix, boolean cached, CompletionParameters parameters)