code: protected List<ResourceTypeHandler<?>> getResourceTypeHandlers() {
          final List<ResourceTypeHandler<?>> handlers = new ArrayList<ResourceTypeHandler<?>>();
          handlers.add(new FileResourceTypeHandler(getRelativeParentDirectory()));
          handlers.add(new UrlResourceTypeHandler());
          handlers.add(new ClasspathResourceTypeHandler());
          handlers.add(new VfsResourceTypeHandler());
          return handlers;
      }
docs: Creates a list of {@link ResourceTypeHandler}s. Subclasses can optionally
  override this method and add more handlers to the list.
  
  @return