Views and Viewpoints
Definition
What it is
View: A representation of a whole system from the perspective of a related set of concerns. Views are modular allowing a view to utilize multiple notations and a model may be shared between multiple views.
Viewpoints: Each view corresponds to only one viewpoint. Viewpoints define resources and rules for constructing views.
View is
What you see
System/model specific
Viewpoint is
What it is not
Rationale
The model of a system is often rich in information and addresses concerns from a wide range of stakeholders. To reduce perceived complexity, separate the concerns into different views. Views and Viewpoints provide a 'window' into the model that allows the viewer to obtain the information that they need.
Each view addresses one or more concerns of the stakeholders. If a view does not answer some stakeholder concerns then do not create view.
Pre-condition
Post-condition
Problem
Methodology
Method
Each architectural viewpoint is determined by:
Create a Viewpoint
Viewpoint name
Stakeholders addressed by the viewpoint
Architectural concerns “framed” by the viewpoint
Method used to construct, illustrate and analyze resulting view
Source (if any) of the viewpoint
(optional) Consistency or completeness checks associated with underlying method to be applied
(optional) Evaluation or analysis techniques to be applied
(optional) Heuristics, patters or guidelines which aid the synthesis of an associated view
Create a View
Apply a Conform edge from View to Viewpoint (edge is now replaced with a solid line with an empty arrow, similar to the Generalization edge)
Apply a Expose edge from View to element that the View exposes (e.g. “Requirements” package)
Heuristics
Process
Parts
Architectural Description (AD): Collection of products to document an architecture. AD addresses all identified stakeholders' concerns. Includes at least,
Identification of stakeholders and concerns
Selection and declaration of the viewpoints used
Views, each conforming to a viewpoint
Any known inconsistencies
Architectural rationale
Stakeholder: Individual, team or organization with interests in, or concerns relative to, a system
Concerns: Those stakeholders' interests which pertain to the development, operation, or other key characteristics of the system
Use Cases
Scenarios