code: public String getAlternativeText() {
  		String text = getComponentModel().alternativeText;
  		if (text != null) {
  			return text;
  		}
  		Image image = getImage();
  		if (image != null) {
  			return image.getDescription();
  		}
  		return null;
  	}
docs: Retrieve the alternative text for the image.
  <p>
  Returns the alternative text set via {@link #setAlternativeText(String)}. If this has not been set and an image
  resource is providing the image then the description of the image resource is returned. Otherwise return null.
  </p>
  
  @return the alternative text for the image.