Software Engineering 9th Ed by Sommerville - Chapter 5

Advantages of model-driven engineering

- Allows systems to be considered at higher levels of abstraction - Generating code automatically means that it is cheaper to adapt systems to new platforms.

Use of graphical models

- As a means of facilitating discussion about an existing or proposed system - As a way of documenting an existing system - As a detailed system description that can be used to generate a system implementation

Interaction models

- Helps to identify user requirements. - Highlights the communication problems that may arise. - Understands if a proposed system structure is likely to deliver the required system performance and dependability.

A computation independent model (CIM)

- Important domain abstractions used in a system. - CIMs are sometimes called domain models.

Model driven architecture

- MDA - Model-focused approach to software design and implementation that uses a subset of UML models to describe a system.

Model-driven engineering

- MDE - Models rather than programs are the principal outputs of the development process.

State machine models

- Model the behaviour of the system in response to external and internal events. - Show the system's responses to stimuli so are often used for modelling real-time systems. - Show system states as nodes and events as arcs between these nodes.

Disadvantages of model-driven engineering

- Models for abstraction and not necessarily right for implementation. - Savings from generating code may be outweighed by the costs of developing translators for new platforms.

Behavioral models

- Models of the dynamic behavior of a system as it is executing. - They show what happens or what is supposed to happen when a system responds to a stimulus from its environment.

A platform independent model (PIM)

- Operation of the system without reference to its implementation. - The PIM is usually described using UML models that show the static system structure and how it responds to external and internal events.

Event-driven modeling

- Shows how a system responds to external and internal events.

Data-driven modeling

- Shows the sequence of actions involved in processing input data and generating an associated output. - Is particularly useful during the analysis of requirements.

Platform specific models (PSM)

- Transformations of the platform-independent model with a separate PSM for each application platform.

System boundaries

Define what is inside and what is outside the system.

Context models

Illustrate the operational context of a system - they show what lies outside the system boundaries.

External perspective

Model the context or environment of the system.

Behavioral perspective

Model the dynamic behavior of the system and how it responds to events.

Interaction perspective

Model the interactions between a system and its environment, or between the components of a system.

Structural perspective

Model the organization of a system or the structure of the data that is processed by the system.

State diagrams

Show how the system reacts to internal and external events.

Sequence diagrams

Show interactions between actors and the system and between system components.

Activity diagrams

Show the activities involved in a process or in data processing

Use case diagrams

Show the interactions between a system and its environment.

Class diagrams

Show the object classes in the system and the associations between these classes.

System modeling

The process of developing abstract models of a system, with each model presenting a different view or perspective of that system.