public function find( $key, $disableLateLoading = null )
    {

        // $disableLateLoading default value management
        if( !is_bool( $disableLateLoading ) ) {
            $disableLateLoading = false;
        }

        // empty key
        if( is_null( $key ) or !is_scalar( $key ) or strlen( trim( $key ) ) === 0 ) {
            return null;
        }

        $class = $this->entityClass;

        try {
            return $this->entityFactory( $key, $disableLateLoading );
        } catch( \Exception $e ) {
            return null;
        }

    }