docs: @Override
  	public void clear() {
  		removeAllUserData();
  		if (this.children != null) {
  			final List<N> nodes = new ArrayList<>(this.children);
  			while (!this.children.isEmpty()) {
  				setChildAt(0, null);
  			}
  			for (final N child : nodes) {
  				child.clear();
  			}
  			nodes.clear();
  		}
  	}