Re: OO programming - illumination?

From: frebe (fredrik_bertilsson_at_passagen.se)
Date: 03/03/05

  • Next message: Ilja Preuß: "Re: Application logic and Business logic" 
    Date: 2 Mar 2005 22:30:10 -0800

    > Commits and rollbacks are an artifact of a particular storage
    paradigm
    > that the problem solution should not have to understand.

    You are wrong again. Transaction handling is not only related to
    storage. In distributed transactions, multiple resources can
    participate. Besides databases, messsage exchage systems use to
    participate in distributed transactions. Virtually any kind of resource
    may participate. The problem solution really need to understand
    transactions.

    > Because if persistence is on flat files or clay tablets, there is no
    > such thing as a rollback.

    It might be. In the old days working with flat files, transaction
    handling could be done, by first making a copy of the entire file. If
    rollback should be done, the modified file was overwritten by the copy
    file.

    > the OO version would be
    > significantly more verbose than your RAD example. Consider the
    > following interfaces:
    Can you show me the code that corresponds to my "main" method. I am not
    sure I understand your example without the full picture.

    Anyway, I am very amazed to see so much similarites with your code and
    Butler. Isn't SQLDispatcher a generic class that could be reused by
    every application that are using a SQL database? In my example I have a
    OrderTable class too, generated from the schema structure. I never
    thought you could had a class that reflects the database schema. In
    Butler there are a generic Table class that have the save functionality
    as your SQLDispatcher, and every generated table-class subclasses this
    Table class.

    Fredrik Bertilsson
    http://butler.sourceforge.net

  • Next message: Ilja Preuß: "Re: Application logic and Business logic"

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