php - How to get the JSON in joomla 3 -

i want know joomla 3 supports json format, how output in json format in data in xml format. if possible pls reply on it. i'll thankful guys.

$document = jfactory::getdocument();  // set mime type json output. $document->setmimeencoding('application/json');  // output json data. echo json_encode($data);