* @return
*/
public static RollingWindowSet keyed_counter_rolling_window_set(
int num_buckets, Integer[] bucket_sizes) {
RunnableCallback updater = new IncValUpdater();
RunnableCallback merger = new IncValMerger();
RunnableCallback extractor = new IncValExtractor();
return RollingWindowSet.rolling_window_set(updater, merger, extractor,
num_buckets, bucket_sizes);
}