code: public static Image findImageById( String imageId, List<Image> images ) {
  
  		Image result = null;
  		for( Image img : images ) {
  			if( img.getId().equals(imageId)) {
  				result = img;
  				break;
  			}
  		}
  
  		return result;
  	}
docs: Finds an image by ID.
  @param imageId the image ID (not null)
  @param images a non-null list of images
  @return an image, or null if none was found