Rational Rose 2000
Use Case Realization Structure
Objectives
Discuss what a Use Case Realization is.
Define when the use case realizations are created.
Create Use Case Realization structure in Logical View.
Create a Use Case Realizations package
Create Individual use case realization packages
Create a Traceabilities diagram
Where Are We?
Interaction diagrams are created and refined during the elaboration phase of this workflow for architecturally significant use cases, along with class
diagrams (not to be confused with analysis classes…)and the flow of events.
Interaction diagrams for remaining use cases are created during the
Where Are We?
The Use Case Realization structure is created during architectural analysis.
This may be skipped if there is low architectural risk, or the architect is experiences in
Use Case Realizations
“Use Case Realizations” is a term used in the Rational Unified Process.
In particular, they are captured in the Logical View (Design Model) (think: 4+1 architectural view).
Purpose of a Use Case Realization
separate the concerns of the specifiers of the system (as
represented by the Use Case Model and the requirements of the system) from the concerns of the designers of the system.
A Use Case Realization represents the design perspective of a Use Case.
It is a collaboration of components that realizes (or performs) some use case.
The realization describes how the behavior of a use
case is performed by the collaboration of elements
(classes, …) within the system.
Use Case Realizations
Main purpose is to provide a bridge
between the descriptions of the system
used by external stakeholders (principally users and customers), such as use cases and requirements, and the descriptions of the system used by the internal
stakeholders (principally developers and testers.)
Use case realizations overcome a problem area that is key in many other development techniques – the discontinuity between
requirements and design.
They provide for traceability!
Use Case Realizations
The separation of the use-case realization
from the use case is essential as it decouples the use case from its implementation, allowing the design to progress without affecting the
baseline requirements captured in the use case.
Typically, for each use case in the use case model, there will be a use case realization in the design model (in logical view ) with a
realization relationship to the use case.
Typically there is at least one test case for
every use-case realization (scenario-based)
Use Case Realizations
Use Case realizations can be expressed visually using UML constructs such as
sequence and collaboration diagrams OR textually using structured English.
In fact, when people write their use cases with an implementation focus, discussing the
components of the system and the way that
they work, they are actually creating a textual
use-case realization rather than a use–case
description.
Compare:
Strength of Use Cases
Communicate with end user in
• Language of the end user / stakeholders
• Problem space
Weaknesses of Use Cases
Not formal
Fuzziness in places
Key Concepts
Use case realizations and the Logical View
Represent the concerns of the system’s designers Thus, created during the Logical View. (RUP) (analysis and design)
Moved from concerns of the end user to that of the system designer.
The Logical View addresses the functional requirements of the system. The Use Case View is used to communicate with the end user or customer.
Use case realization packages
Packages help organize the model and vital for using Rose – distribution of functions, work assignments, distribution, etc.
• We will create a package called Use Case Realizations and in it create packages for each use case realization.
Traceabilities diagram
Created in the Use Case Realizations package to help verify that the use cases (from use case view) are represented in the design model
Use Case Realization - Practicuum
Objectives
Create the use realization structure in the Logical View.
Create the Traceabilities diagram.
Add Package Called Use Case Realizations
Use Case Realizations package added
Bring up your model in Rose
In Browser, expand Logical View Right Click Logical View
then click New Click Package.
Type Use Case Realizations over NewPackage, then click of Leave model open.
Now, will create use case realization packages for each use case..
Depending on your version of RR,
you may need to expand the Design Model
Add Three Use Case Realization Packages
Use case realization packages added under Use Case Realizations
In book example:
Add three use case realization packages.
Right Click Use Case Realizations, New, Package,
Type Use Case Realization – Register for Courses
over NewPackage.
Repeat steps 1 – 3
to add Use Case Realization - Login and Use Case Realization – Close Registration.
Create Traceabilities Diagram
In the browser, the Traceabilities diagram added under Use Case Realizations package
Right click Use Case Realizations; click New;
Click Use Case Diagram; Type ‘Traceabilities’
over New Diagram.
Double-click the Traceabilities diagram.
Use case Use case realization
Namespace warning
Create Traceabilities Diagram
• Add your Use Cases to the diagram from your Use Case View.
• Drag those Use Cases onto the diagram; Repeat for all use cases in the UC View
• Add the Use Case realizations… From the toolbar, select a Use Case icon and place it on the diagram. Right click to get the Open Specification; type in the name;
and in the stereotype list select Use-case realization. Then, OK.
(Ignore namespace warning) (You will note the appearance of the oval)
Use case realizations added in browser
Create Traceabilities Diagram
Before continuing with the
Traceability diagram, this is what we have.
Use case realization moved its package
Create Traceabilities Diagram
Collapse the Use Case View. (Done with this at this time…)
In the browser, drag the use case realizations under their respective packages as shown to the right.
Repeat this for all Use Case Realizations.
(Relocate them in their packages)
Use case realization identified with its package
Continuing to Create Traceabilities Diagram
The Traceability
Diagram we have is:
Continuing Traceabilities Diagram
Unidirectional association added
Stereotype added
--- Add the unidirectional
associations via the toolbar Drag the mouse from the Use Case realization icon to the Use Case.
Repeat for all Use Case Realizations.
