public void readExternal(Element element) throws InvalidDataException { List<Element> subPanes = element.getChildren(ELEMENT_SUBPANE); for (Element subPane : subPanes) { String subId = subPane.getAttributeValue(ATTRIBUTE_SUBID); TreeState treeState = new TreeState(); treeState.readExternal(subPane); myReadTreeState.put(subId, treeState); } }