/**
  * Persists a cache item immediately.
  *
  * @param CacheItemInterface $item
  *            The cache item to save.
  *            
  * @return bool True if the item was successfully persisted. False if there was an error.
  */
 public function save(CacheItemInterface $item)
 {
     $item->setIsHit(true);
     $this->data[$item->getKey()] = $item;
     return true;
 }