Newly created class in not available in joomla

I have created a new class 'KalturaCategory' for category list retriving
at - joomla\components\com_kalturavideo\client\KalturaClient.php

but it cant be available in module

what to do?

if i include the client file in module

include_once("components/com_kalturavideo/client/KalturaClient.php");

it shows redeclaration error