Overview of CA ADS Application Development › Application Development

Application Development

Flexible Application Development Environment

CA ADS provides a flexible application development environment. You can define application components in whatever order makes the most sense given the application you need to define. For example, you can define the executable structure, screen displays, and runtime flow of control for the entire application before you define any modules of process code for the application. Alternatively, you can fully define all components, including modules of process code, for a subset of the application before even beginning to define components for the remaining application.

Methodology

This manual illustrates CA ADS concepts by showing you how they apply to the definition of a sample application. The methodology presented here shows you one way to efficiently develop a new application by using CA ADS development tools. At your site, other application development strategies may be employed.

Structure Diagram

A useful first stage in developing a new CA ADS application is to develop a structure diagram based on the specifications for the application. Drawing a structure diagram for an application is useful because:

• The application's functional requirements are clarified before any specific development occurs. Potential design and development misunderstandings are often caught in the process of developing a structure diagram.
• The structure diagram is a development resource for application developers throughout the development cycle. While developing application components, the developer can use the structure diagram as a reminder of how each component relates to the entire application. CA ADS application components fit directly into an application structure diagram.

Sample Application

The structure diagram for a small Personnel application is shown below. This application allows users to maintain information on departments and users. Related data, such as office addresses and insurance information, is also collected and stored by using this application. You will develop the Department portion of this application in this manual.

Functions

As shown in this sample structure diagram, the application structure is made up of functions. Each function is related to work performed by the end user on a single screen. For example, the Personnel application includes functions such as ADDDEP, MODDEP, and DELDEP, which allow you to add, modify, and delete department records in the database. Menu functions, such as MAINMENU and DEPTMENU, allow you to select other functions in the application. Other functions allow you to return to previous menus (functions BACK and TOP) and to exit from the application (function EXIT).

To reduce repetition of information, this manual presents steps for developing only the Department portion of this sample Personnel application. Remaining portions of the Personnel application can be added to the Department application at any time. The strategy of defining different portions of applications at different times is particularly useful when developing large applications.

Defining the Application

As soon as the application structure diagram is completed and approved, you can begin to define the application in the data dictionary. In this manual, you will define the sample Department application in two steps:

1. You will develop a prototype application based on the approved structure diagram for the application.

   The CA ADS runtime system simplifies the definition of prototypes by automatically performing many basic processing activities, such as displaying a screen. You can define a prototype without writing any process logic. Additionally, you can execute a prototype application before the database is developed.

2. You will enhance the tested and approved prototype by adding process logic.

Advantages

Advantages to developing a prototype application before defining any process logic for the application include:

• Timely feedback— End users and other interested people can execute the completed prototype application to see how well screens meet their needs and to verify that flow of control from function to function makes sense based on their job responsibilities.
• Ease of modification— Improvements suggested by end users can be included in the prototype application quickly because you do not have to modify any process logic or database definitions.
• Efficient use of development time— The prototype application developed for early testing is itself developed into the final production application. Components created for the prototype are all used in the final application.