Get User ID with Jumi in Joomla

If you include a php file to an article with Jumi, you can get the user id with this:

defined('_JEXEC') OR defined('_VALID_MOS') OR die( "Direct Access Is Not Allowed" );

$jAp= & JFactory::getApplication();
$user =& JFactory::getUser();
echo $user->get('id');