for accurate communication, since a project can have several participants, each from different...
TRANSCRIPT
For accurate communication, since a project can have several participants, each from different background.
Represent a given aspect of the system
We will use UML, widely known and accepted
UML is also well accepted in the industry
In all activities and phases
Functional model: use case diagram
Object model: class diagram
Dynamic model: interaction diagram, activity diagram, state charts
Used during inception, requirements elicitation and requirements analysis
Describe the functionality of the system
Use cases focus on the behavior of the system from an external point of view.
A use case describes a function provided by the system that yields a visible result for an actor
A Use Case diagram shows you some of the use cases in your system, some of the actors in your system, and the relationships between them.
use case is a high−level piece of functionality that the system will provide.
Use case: describes a function provided by the system that yields a result for an actor
An actor is anyone or anything that interacts with the system being built.
Extend relationship: The extend-relationship connects an extension use case to a base use case. Use it for exceptional cases.
Reduce redundancy
Describe the structure of the system
Conceptual class diagram
Design class diagram
Play a Dice Game: A player picks up and rolls the dice. If the dice face value total seven, they win; otherwise, they lose.
Represent the dynamic behavior of the system
Visualize the communication between objects
Define the dynamic behavior of an individual object as a number of states and transition between them
State: particular set of values for an object
Unlike the interaction sequence diagram, which shows all the objects involved in one scenario or use case and how they collaborate together, the statechart expresses THE WHOLE LIFE OF ONE OBJECT in the domain
Three push-buttons on the lecturer’s desk: full, off, dim.
Power switch on wallAlways powers up
‘off’Thereafter, press a
switch to change brightness or turn on/off.
Full on
Off Dimmed
Full Dim
Dim
Off
Off
Full
Power on
Power off Power off
Power off
DimOff
Full
Describes the behaviour of a system in terms of activities
Activity = set of operations
The completeness of one activity triggers a transition to another activity
They are similar to flow chart
System: an organized set of communicating pats
System can be decomposed into subsystems
Subsystems are composed into objects
How to deal with complex systems, especially software?
Model, use models to represent the system
Every model focus on one area at a time
Then the models will be refined
Data type: Integer, floatAbstract data type: implementation
independent such as set, PersonClass: abstraction on o-o modellingAbstract classes:Operations (methods)AttributesObject:MessagesPrototyping
Use case specification includes:Use case NameParticipating actorsFlow of eventsEntry conditionsExit conditionsQuality Requirements
Use cases are written in natural languages
Not technical
Each use case describes all possible scenarios
Scenario: instance of a use case
When actors and use case communicate they exchange information