code: @Override
    public OperationFuture<CASValue<Object>> asyncGets(final String key) {
      return asyncGets(key, transcoder);
    }
docs: Gets (with CAS support) the given key asynchronously and decode using the
  default transcoder.
  
  @param key the key to fetch
  @return a future that will hold the return value of the fetch
  @throws IllegalStateException in the rare circumstance where queue is too
  full to accept any more requests