public function put($resource)
    {
        // remove from busy queue
        $this->busyQueue->detach($resource);

        // push to free queue
        $this->freeQueue->push($resource);
    }
public function put($resource)
    {
        // remove from busy queue
        $this->busyQueue->detach($resource);

        // push to free queue
        $this->freeQueue->push($resource);
    }
{@inheritdoc}