Each user within JomSocial is represented by a special object called CUser. CUser inherit all JUser object properties and added a couple new functionality.
To retrieve user object
{code}// Return user with the given id
$user =& CFactory::getUser($userId);
// Return current logged-in user. If no one is logged-in, it will
// return a visitor object
$user =& CFactory::getUser();{/code}
To retrieve any user-specific information from custom field
{code}$user =& CFactory::getUser($userId);
$data = $user->getInfo('FIELD_CODE');{/code}