code: protected void updateClassnames(HashMap<String,HashSet<String>> cache, String superclass, HashSet<String> names) {
      if (!cache.containsKey(superclass))
        cache.put(superclass, names);
      else
        cache.get(superclass).addAll(names);
    }
docs: Updates cache for the superclass.
  
  @param cache	the cache to update
  @param superclass	the superclass
  @param names	the names to add