public function importClassAction()
{
$class = Object\ClassDefinition::getById(intval($this->getParam("id")));
$json = file_get_contents($_FILES["Filedata"]["tmp_name"]);
$success = Object\ClassDefinition\Service::importClassDefinitionFromJson($class, $json);
$this->removeViewRenderer();
$this->_helper->json(["success" => $success], false);
// set content-type to text/html, otherwise (when application/json is sent) chrome will complain in
// Ext.form.Action.Submit and mark the submission as failed
$this->getResponse()->setHeader("Content-Type", "text/html");
}