VBM - Vision Based Methodology™

Activity 8: Specifying the Vision

Structure and Action Diagramming - Program Specification

Action Diagrams and Pseudo Code

A Recommended Program Structure for third level languages:

Main

A nnn - Initialization

C nnn - Processing

D nnn - Termination

F nnn - Format

H nnn - Page Heading

I nnn - Internal Table

R nnn - Read (from a sequential file)

S nnn - Data Base Call

W nnn - Write (to a sequential file or a report)

X nnn - External Program Call

Z nnn - Abend

Using "Code" and "Skeleton" Based Generators

Obviously, a code generator should be selected which will generate the programming language syntax chosen for the creation of the business application. This decision will have a definite impact on the course the design process will take. Each potential type of generation approach has its own unique considerations which the design team should closely examine. In addition, some of the following questions should should also be answered, before making the final commitment to a code generation approach:

• Will the code generator be used only to create a base set of programs which will then be further hand coded, or will the code generator be used to create the final completed versions of the programs?
• Will the code generator be used for on-going maintenance of the system after the project is complete, or will the programs be maintained by directly by a programmer after the initial delivery?
• How reliable is the product vendor, and will the code generator keep up with the potential technological changes in both the hardware as well as the chosen language's syntax standards?

The use of a code generator can either be a fantastic experience, or an unexpected nightmare, depending on the approach employed by the individual code generation product. If the team has never used the code generator product before, some type of a pilot project should be undertaken first, certainly before any design activities begin for a major system building effort. Better yet, see if the vendor can provide a consultant to be on site working with the team throughout the design and construction phases.

Some of the more common code generation approaches:

• Screen/Database/Report Definition Approach (what you see is what you get)
• CASE Based Approach
• Psuedo Code Based Approach (using this method you still feel that you are programming, you are just programming less)
• Skeleton Based Approach (code within user exits)