/** {@inheritDoc} */ public void render(Attribute attr, Request request) throws IOException { if (attr == null) { throw new CannotRenderException("Cannot render a null attribute"); } if (attr.isPermitted(request)) { Renderer renderer = rendererFactory.getRenderer(attr.getRenderer()); Object value = evaluate(attr, request); if (!(value instanceof String)) { throw new CannotRenderException( "Cannot render an attribute that is not a string, toString returns: " + value); } renderer.render((String) value, request); } }