Artifacts > Environment Artifact Set > Development Case > Guidelines > Important Decisions in Analysis & Design

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Decide How to Perform the Workflow To top of page

The following decisions should be made regarding the Analysis & Design discipline's workflow:

  • Decide how to perform the workflow by looking at the Analysis & Design: Workflow. Study the diagram with its guard conditions, and the guidelines. Decide which workflow details to perform and in which order. 
  • Decide what parts of the Analysis & Design workflow details to perform. The following parts can be introduced relatively independently from the rest.

Part of workflow

Comments
Database design Only used if the entities are going to be stored in a database. If you decide against doing database design, it means that you do not develop any Data Model.  
Real time, using Rational Rose RealTime If you decide to not do this, it means that you do not develop artifacts such as Capsule and Protocol.
  • Decide when, during the project lifecycle, to introduce each part of the workflow. It is sometimes possible to wait until the Elaboration phase before introducing the Analysis & Design discipline. For example, if the development is in a well-understood domain, does not have demanding performance (or other non-functional) requirements, and will be based on a well-tried architecture, there is little need for prototyping during inception.

Document the decisions in the Development Case, under the headings Disciplines, Analysis & Design, Workflow.  

Decide How to Use Artifacts To top of page

Make a decision about what artifacts to use and how to use each of them. The table below describes mandatory artifacts and those artifacts used only in certain cases. For more detailed information on how to tailor each artifact, and a discussion of the advantages and disadvantages of that specific artifact, read the section titled "Tailoring" for each artifact.

For each artifact, decide how the artifact should be used: Must, Should, Could or Won't. For more details, see the Guidelines: Classifying Artifacts.

Artifact Brief Tailoring Comments (see the artifact for details)
Analysis class Could have. Used if a separate analysis model is developed and maintained.
Analysis model Could have. See Analysis class.
Capsule For real-time systems, but can be useful in modeling and designing any system that has a high degree of concurrency.
Data model Could have. Used to describe the logical and possibly physical structure of the persistent information.
Deployment Model Must have if you deploy the system.
Design class Must have if you do Analysis & Design. The issue is deciding which stereotypes to use.
Design model Must have if you do Analysis & Design.
Design package Must have if you do Analysis & Design. Decide which stereotypes to use and how many levels of packages.
Design subsystem Must have if you do Analysis & Design.
Event May be useful for systems that respond to many external events.

Required for real-time systems.
Interface Could have.
Protocol Required for real-time systems.
Signal May be useful for systems that require concurrency and are event-driven.

Required for real-time systems
Software Architecture Document (SAD) Must have if you do Analysis & Design. The main issue is deciding which architectural views you need in your specific project.
Use-case realization Must have if you do Analysis & Design.

Tailor each artifact by performing the steps described under the heading "Tailor Artifacts per Discipline" in the Activity: Develop Development Case.

Decide Which Reports to Use To top of page

Make a decision about what reports to use. As a starting point, consider using the following reports:

Decide How to Review To top of page

Decide on the review level for each artifact and capture it in the development case. See Guidelines: Review Levels for details. 

Decide how to review and approve the results of Analysis & Design, and to what extent the results will be reviewed.

The advantages of a design review are:

  • It detects problems that are impossible, or very difficult, to detect in testing. For example, issues of style, and layout. 
  • It is a way to enforce a common modeling style and an opportunity for individuals to learn from each other. 
  • It detects those defects that wouldn't otherwise get detected until later in the project during tests.

The disadvantages of a design review are:

  • It takes time and resources. 
  • It is easily misused if not managed well.

The factors that can be altered are review techniques, resources, and scope. The following are some examples of what you can decide to do on your project:

  • Decide that local changes to a subsystem are reviewed only by one peer, who conducts an inspection and hands over the results on paper.
  • Decide on which parts of the design will not be reviewed at all; for example, review only some classes for each member of the project and hope that this assures the style is of a similar quality to the rest of the results.
  • Decide that the Software Architecture Document will be reviewed by customer during a separate meeting.
  • Decide to use formal review meetings for changes in important interfaces; that is, interfaces that affect the work of several project members.

For more information about reviewing and different kinds of reviews, see Work Guideline: Reviews.

Decide Whether to Generate Code To top of page

The way you do design differs depending on whether you generate code from the design model or not. If you generate code, the design needs to be very detailed. On the other hand, if you do not generate code from the design, there is no need to be very detailed in the design. On the contrary, the details in the design have to be synchronized manually with the code.

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