code: protected TextArea<T> newTextArea(final String id, final IModel<M> model)
  	{
  		final IModel<T> textAreaModel = new PropertyModel<>(model.getObject(), getId());
  		return ComponentFactory.newTextArea(id, textAreaModel);
  	}
docs: Factory method for create the new {@link TextArea}. This method is invoked in the constructor
  from the derived classes and can be overridden so users can provide their own version of a
  new {@link TextArea}.
  
  @param id
  the id
  @param model
  the model
  @return the new {@link TextArea}