fun categories: HashSet[String] import StringCopyHashSet,
	  StringCopyHashSet.add, StringCopyHashSet.collection  in "Java" `{
		Set<String> java_set = self.getCategories();
		NitObject nit_hashset = new_StringCopyHashSet();

		if (java_set == null) return nit_hashset;

		for (String element: java_set)
			StringCopyHashSet_add(nit_hashset, element);

		return StringCopyHashSet_collection(nit_hashset);
	`}