code: protected Class getPrototypeClass(T content) {
      if (prototypes.size() == 1) {
        return prototypes.get(0).getClass();
      } else {
        return binding.get(content.getClass());
      }
    }
docs: Method to be implemented by the RendererBuilder subtypes. In this method the library user will
  define the mapping between content and renderer class.
  
  @param content used to map object to Renderers.
  @return the class associated to the renderer.