public static String[] wordList(Collection root) throws XMLDBException {
final String query = "util:index-keys(//*, \"\", function($key, $options) {\n" +
" $key\n" +
"}, 100, \"lucene-index\")";
XQueryService service = getXQueryService(root);
ResourceSet result = service.query(query);
ArrayList<String> list = new ArrayList<String>();
for (ResourceIterator iter = result.getIterator(); iter.hasMoreResources(); ) {
Resource next = iter.nextResource();
list.add(next.getContent().toString());