Subject:
Re: muon digit container design
From:
David Adams <dladams@bnl.gov>
Date:
Fri, 05 Oct 2001 08:57:24 -0400
To:
Hong Ma <hma@pony.phy.bnl.gov>
CC:
Torre Wenaus <torre@wenaus.com>, Srini Rajagopalan <srinir@bnl.gov>, Pavel Nevski <nevski@bnl.gov>, Yuri Fisyak <fisyak@bnl.gov>, Alex Undrus <undrus@bnl.gov>, David Adams <dladams@bnl.gov>

Hong:

I have replies to a couple of your comments. I hope we are converging on
the essential differences.

1.

    You have to consider "raw data" as a type of persistent event
source.  And you don't want the collection to hold a pointer to raw data,
or any persistifiable objects.


I agree that raw data is persistent. If the data unpacking is to be done on
demand then something must hold a pointer to the raw data. I propose to do
this unpacking directly in the container (or a class held by the container)
rather than go through StoreGate.



2.

    If I understand your points correctly, you would choose to have
different MuonDigitContainer implementation in EF and offline environment.
Then, you are required to have a Abstract Base Class (ABC) for this
container.  That ABC is what algorithms will have dependency on. This way,
the algorithms can be run in online and offline environment. By offline
environment, I mean  reading Digit objects from Objy. No Raw Event whatsoever.

>
> ...

No, I said nothing about the implementation and I agree that it doesn't seem
that inheritance is appropriate here.

3.
    Besides, in your implementation for your online
MuonDigitContainer, you will have to manage the partial unpacking.


Yes, that is the plan. This would probably be done indirectly by holding an
unpacker but the effect is the same.

da


-- 
David Adams                      desk: 631-344-6049
Brookhaven National Lab          fax: 631-344-5078
PAS group, Building 510A         email: dladams@bnl.gov
Upton, NY 11973-5000             http://www.usatlas.bnl.gov/~dladams