protected function setState($state)
    {
        $this->queryState = $state;
        $map = [
            static::STATE_BUSY => static::CLIENT_POOL_STATE_BUSY,
            static::STATE_READY => static::CLIENT_POOL_STATE_READY,
        ];
        $statePool = isset($map[$state]) ? $map[$state] : static::CLIENT_POOL_STATE_NOT_READY;
        $this->changeState($statePool);
    }