private function alter($key, $value)
    {
        if ($this->has($key)) {
            $this->data[$key][self::CACHE_PARAM_VALUE] = $value;
        }
    }
private function alter($key, $value)
    {
        if ($this->has($key)) {
            $this->data[$key][self::CACHE_PARAM_VALUE] = $value;
        }
    }
private function alter ( $ key , $ value ) { if ( $ this -> has ( $ key ) ) { $ this -> data [ $ key ] [ self :: CACHE_PARAM_VALUE ] = $ value ; } }
Alters key's value

@param string $key
@param mixed $value
@return void
Alters key s value