private void checkID(final JElement je) { final org.jdom2.Element emt = (org.jdom2.Element) (je.shadow); if (emt.hasAttributes()) { for (final Attribute a : emt.getAttributes()) { if (a.getAttributeType() == AttributeType.ID) { if (idmap.put(a.getValue(), je) != null) { throw new DOMException( DOMException.INVALID_STATE_ERR, "Multiple elements with id " + a.getValue()); } } } } }