Neos\Cache\Frontend\FrontendInterface::has PHP Method

    public function has($entryIdentifier);

 /**
  * Tests if an entry exists in the cache.
  *
  * @param string $id The cache id of the entry to check for.
  * @return boolean TRUE if a cache entry exists for the given cache id, FALSE otherwise.
  */
 public function contains($id)
 {
     return $this->cache->has($this->convertCacheIdentifier($id));
 }