Domain modeling Flashcards
Get to know class diagrams and UML
What is a class diagram?
A diagram that shows classes (make up a domain or a part of the system) and relationships among them
What kind of relationships may exist between classes?
- Association
- Aggregation
- Composition
What is a degree of association?
Number of roles in that association
What is a binary (ternary) association?
An association that has two (three) roles for the participating objects to play
How many class may be involved in a ternary association?
At least one
E.g: A person is recommending a person to another person
How to interpret multiplicities of ternary association?
Take each pair of the classes and associates it with the third class
What is an association class?
A class that created by an association that has data or behaviours
How to represent an object in UML?
objectName : className
What is a link?
An instance of an association
What is an aggregation?
A special form of association, also known as whole-part and part-of relationship (composite and component object)
The condition that aggregation must satisfy
It must not be circular
Factors that help to decide whether it’s an aggregation or not?
- Existence dependency
- Non-shareability
- Exclusive access control
What is a composition?
A stronger form of aggregation that must have existence dependency and non-shareability
