RE: Free OS/400

["Joe Pluta" <joepluta@xxxxxxxxxxxxxxxxx>]

> From: Jim Damato
>
> What exactly are you looking for in a migration path?  Client
> server and web
> software architecture is so different and so much more complex than
> traditional AS/400 programming.  It's like writing a book and
> expecting your
> word processor to provide a migration path to a movie.  It's so easy to
> blame IBM, but the expectations are so unrealistic.
-------------

This is where I disagree.  It depends on what you mean by "traditional"
programming.  If you mean 1980's style monolithic programming where the
business logic and the UI are inextricably intertwined through the use of
common indicators implemented via 30,000 line programs, then yes indeed, you
will have difficulty moving to any other UI, but that situation exists
regardless of your toolset.

If, on the other hand, the code adheres to the trends of the last decade or
so, with modular programs where the user interface is separate from the
business logic, then it's quite easy to move from a green screen to a UI
independent environment.

If, as is likely, your code is somewhere in the middle, there is a logical,
simple path.

1. Mechanically separate your business logic and user interface
2. Wrapper your interface within an intelligent messaging architecture
3. Rewrite the sections of code that need performance improvements
4. Remove the wrapper for the rewritten sections

It's simple.  Part three is time consuming, of course, but not that
difficult, especially when you've used part two to provide a zone of change
where you can work without undue time pressures.

All programming that interacts with the user is a series of transactions
between the user and the host machine.  There is nothing fundamentally
different about the web interface and any other interface if you've designed
a solid client/server infrastructure.  Structuring and codifying the
user/host interaction leads naturally to exactly that sort of robust,
flexible client/server environment.

The very best, most-used websites today, such as Google or Travelocity or
Monster.com, have very simple user interfaces that are really no different
from anything we're doing with green screens.  Get data, send to server,
show results.  Most of our green screen applications can be adapted to that
paradigm quite easily.  Right now, my toolset converts a green screen
program directly to an HTML-capable application in a few seconds.

Joe Pluta
www.plutabrothers.com
"Adapting Tomorrow's Architectures to Today's Applications"

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