class LinkkiInMemoryContainer extends com.vaadin.v7.data.util.AbstractInMemoryContainer<T, Object, com.vaadin.v7.data.Item> implements com.vaadin.v7.data.Container.Hierarchical {

    public void setItems(Collection<? extends T> items) {
        requireNonNull(items, "items must not be null");

        this.roots = new ArrayList<>(items);

        getAllItemIds().clear();
        getAllItemIds().addAll(items);

        fireItemSetChange();
    }

}