getItems(array $keys = array()) {@inheritdoc}

saveDeferred(CacheItemInterface $item) {@inheritdoc}

class AbstractAdapter implements

commit() {@inheritdoc}

clear() {@inheritdoc}

commit() {@inheritdoc}

static validateKey(string $key) Validates a cache key according to PSR-6.

deleteItem($key) {@inheritdoc} Parameters

saveDeferred(CacheItemInterface $item) {@inheritdoc}

class FilesystemAdapter extends