void (NamespaceContext namespaceContext, Set<? super LookupElement> list, XmlElement context) { if (namespaceContext != null) { final Collection<String> knownPrefixes = namespaceContext.getKnownPrefixes(context); for (String prefix : knownPrefixes) { if (prefix != null && prefix.length() > 0) { list.add(new NamespaceLookup(prefix)); } } } }