@Override
  public BulkFuture<Map<String, Object>> asyncGetBulk(
         Iterator<String> keyIter) {
    return asyncGetBulk(keyIter, transcoder);
  }
Asynchronously get a bunch of objects from the cache and decode them with
the given transcoder.

@param keyIter Iterator that produces the keys to request
@return a Future result of that fetch
@throws IllegalStateException in the rare circumstance where queue is too
          full to accept any more requests
src/main/java/net/spy/memcached/MemcachedClient.java