Tool Mentor: Performing Use-Case Analysis Using Rational XDE Developer - .NET Edition

Purpose

This section provides links to additional information related to this tool mentor.

• Use-Case Analysis

The steps in this tool mentor match those in the activity. Links to topics in Rational XDE™ online Help are marked with .

Overview

This tool mentor assumes that a Design Model and Use-Case Model have been created in accordance with the XDE Model Structure Guidelines. It also assumes that the Use-Case Model has been populated with actors and use cases by following Tool Mentor: Finding Actors and Use Cases Using Rational XDE.

In this tool mentor, the following steps are performed for each use case in the current iteration:

• [Create the Use-Case Realization](#Create Use-Case Realization)
• [Supplement the Use-Case Descriptions](#Supplement the use-case descriptions)
• [Find Analysis Classes from Use-Case Behavior](#Find Classes from Use-Case Behavior)
• [Distribute Behavior to Analysis Classes](#Distribute behavior to analysis classes)
• [Describe Responsibilities](#Describe responsibilities)
• [Describe Attributes and Associations](#Describe attributes and associations)

The following steps are performed once per iteration:

• [Reconcile the Use-Case Realizations](#Reconcile the Use-Case Realizations)
• [Qualify Analysis Mechanisms](#Qualify Analysis Mechanisms)
• [Establish Traceability](#Establish Traceability)
• [Review the Results](#Review the Results)

Create the Use-Case Realization

For each use case to be analyzed:

1. Navigate to the Design-Model package in which the use-case realizations are to be created. See Rational XDE Model Structure Guidelines.
2. Create a use-case diagram to capture the use-case realizations (unless one already exists). See .
3. Add a collaboration instance to the diagram. Give it the same name as the use case. See .
4. Add a realization relationship to the use case. See .

For more information, refer to the topic in the Rational XDE online Help.

Supplement the Use-Case Descriptions

If the use-case description needs to be supplemented with additional internal behavioral descriptions, this can be done by adding to an existing use-case description created by following the steps outlined in Tool Mentor: Detailing a Use Case with Rational XDE. If the internal behavior of the system bears little resemblance to its external behavior, a completely separate description may be warranted. In this case, attach a separate use-case specification document (see Artifact: Use Case for the template) to the collaboration instance in the model. See .

Find Analysis Classes from Use-Case Behavior

1. Navigate to the package in the Design Model that will contain the analysis classes. See Rational XDE Model Structure Guidelines.
2. Create one or more class diagrams to capture the analysis classes. See .
3. Add the analysis classes. See .
4. Assign analysis class stereotypes as appropriate. See .
5. Add a brief description to each class. See .
6. Optionally associate a document with each class. See .

For more information, refer to the topic in the Rational XDE online Help.

Distribute Behavior to Analysis Classes

1. Navigate to each use-case realization (collaboration instance) to be analyzed.
2. For each independent sub-flow (scenario), create one or more interaction instances. (In the Model Explorer, right-click the collaboration instance, and then click Add UML > Interaction Instance.)
3. Create a sequence diagram for this interaction instance. See .
4. Enter a brief description of the scenario that the sequence diagram depicts. See .
5. Drag and drop actors and participating classes onto the sequence diagram. See .
6. Add messages between the objects. See .
7. (optional) Describe the message. See .
8. To describe how the object behaves when it receives the message, assign an operation to the message. See . (If the operation does not exist, add one to the class as described under [Describe Responsibilities](#Describe responsibilities) below, and then assign the operation to the message.)

For more information, refer to the following topics in the Rational XDE online Help:

Describe Responsibilities

1. Describe responsibilities of the class by adding operations. When you enter the operation name, precede it with two forward slashes (//). The use of these special characters indicates that the operation is being employed to describe the responsibilities of the analysis class. See .
2. Add a description to each operation. See .

Describe Attributes and Associations

Use the following steps below to describe attributes and associations.

Define Attributes

See the topic in the Rational XDE online Help.

Establish Associations Between Analysis Classes

1. (optional) Navigate to each use-case realization, and add a class diagram to show the participants in the use-case realization. See .
2. Add association relationships (either to the “participants” diagram for a use-case realization or to the class diagram in which the class was first introduced, or to both). (See and .) Once a relationship has been added between classes on one diagram, it can be automatically added to another diagram. See .
3. Specify multiplicity on each association end. See .
4. Specify navigability on each association end. See .

Describe Event Dependencies Between Analysis Classes

Give a name or stereotype the associations to indicate event dependencies. See and .

For more information, refer to the topic in the Rational XDE online Help.

Reconcile the Use-Case Realizations

Examine the analysis classes and their associations. Identify and resolve inconsistencies, and remove any duplicates.

For more information, refer to the topic in the Rational XDE online Help.

Qualify Analysis Mechanisms

The analysis mechanisms used by a class and their associated characteristic do not need to be captured in a formal way. A note attached to a diagram (see ) or an extension to the description of the class (see ) is sufficient to convey the information.

Establish Traceability

Add traceability dependencies between the Analysis/Design-Model elements and other models, as specified in project guidelines. For example, there may be a separate business model, conceptual data model, or model of user interface screens that you wish to trace analysis classes to. To do this:

1. Create a diagram for Traceability. See .
2. Drag and drop elements to be traced onto the diagram. See .
3. Add the traceability dependencies (abstraction dependencies optionally stereotyped «trace»). See .

Review the Results

It may be helpful to publish any models to html format. Also note that diagrams can be copied from Rational XDE to Microsoft Word and other programs.

For more information, refer to .