docs: public static ZParams.Aggregate getAggregate(ZParams params) {
  		Collection<byte[]> collect = params.getParams();
  		Iterator<byte[]> iterator = collect.iterator();
  		String key = new String(iterator.next());
  		if (!"aggregate".equals(key)) {
  			return ZParams.Aggregate.SUM;
  		}
  		String type = new String(iterator.next());
  		return ZParams.Aggregate.valueOf(type);
  	}