public synchronized void selectNodes(String qString) throws Exception {
if (qString == null) {
throw new IllegalArgumentException("Argument qString must not be null.");
}
xpath.setQString(qString);
XObject result = xpath.execute(contextNode);
if (result.getType() != XObject.CLASS_NODESET) {
throw new Exception("XPath leads not to a Node or NodeList !");
}
selectionNodeList = result.nodeset();
if (selectionNodeList.getLength() == 0) {
// throw new LexusException(LexusException.NO_NODES_SELECTED);
throw new Exception(".selectNodes(): No nodes selected: " + qString);
}
}