/** * Checks if a cache entry with the specified identifier exists. * * @param string $entryIdentifier An identifier specifying the cache entry * @return boolean TRUE if such an entry exists, FALSE if not * @author Robert Lemke <*****@*****.**> * @author Karsten Dambekalns <*****@*****.**> */ public function has($entryIdentifier) { if (!$this->isValidEntryIdentifier($entryIdentifier)) { throw new InvalidArgumentException('"' . $entryIdentifier . '" is not a valid cache entry identifier.', 1233058486); } return $this->backend->has($entryIdentifier); }