class Element implements IAttributes {

	@Override
	public Set<String> getAttributeNames() {
		Set<String> names = new HashSet<String>();
		if (parent != null) {
			names.addAll(parent.getAttributeNames());
		}
		names.addAll(attributes.getAttributeNames());
		return names;
	}

	public  Element(String id);
	public  Element(Element parent);

}