<No subject>

Charles-A. Rovira crovira at wt.net
Fri Feb 25 00:52:03 UTC 2000


Hello Agree but I don't agree,

polling  is not the solution for most other GUI systems. They use events and triggered responses to the events. The difference is relatively monor, I agree, but it affects the style of the underlying system.

Event driven programming means that your systems and the logic underlying them are re-entrant. It also affects your design for dealing with layered apps since a GUI event can triggen a GUI response which can in turn produce a Business Logic event which elicits a bisiness logic response and so on up the layers (GUI, Client-side Business Logic, Server-side Transaction logic, Data base) until a all layers acknowledge process completion.

Its much easier to design and implement layered applications with event-triggers and responses. If you intend to do any business applications you won't be able to do without the layered approach since different parts of an organization and external entities wich deal with different parts of an organization have their own auditing and informational requirements. (Business app.s are simple, until you see all the hands on the rudder and al the fingers in the pie.)

There are people who will be examining the output of a business app. you scrap today who aren't even born yet :-) You have to take a long term view to systems like Human Resources, payroll and pension. You also have to take a long term view to record auditing, transcation auditing, data base archives and thge terabytes of data that can come back and haunt a corporation years after a mistake was made (like records of deposits by German authorities into numbered Swiss
bank accounts from nineteen thirty nine to nineteen forty five.)

-Charles-A.





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