The document discusses different types of UML diagrams used for object-oriented analysis and design. It focuses on class diagrams and describes the notation used to represent classes, attributes, operations, relationships between classes like association, aggregation, composition, generalization, and realization. Key class diagram elements like class visibility, parameter directionality, and multiplicity are also explained through examples.

1. Object Oriented
Analysis and
Design L10
IT1206
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
1
Sameera
Gunathilaka
Lead Software
Engineer
ERP Technical
Consultant

2. Types of UML
Diagrams
(Modelling Types)
Structural UML
diagrams
Package diagram
Object diagram
Component diagram
Composite structure
diagram
Deployment diagram
Behavioural UML
diagrams
Activity diagram
Sequence diagram
Use case diagram
State diagram
Communication diagram
Interaction overview
diagram
Timing diagram

3. Recap: What is a Class?
• A Class is a blueprint(template) for an
object
• We use classes to create objects
• Classes describe the type of objects,
while objects are usable instances of
classes
• Objects have states and behaviours
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD 3

4. Example
A dog has - color,
name, breed as well
as behaviors -
wagging, barking,
eating. An object is
an instance of a class.
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 4

5. UML Class
Notation
• Class encapsulates: attributes (state) and operations (behaviour)
• attribute has a type
• operation has a signature
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 5

6. Example
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 6

7. Class Visibility
• + denotes public attributes or operations
• - denotes private attributes or operations
• # denotes protected attributes or operations
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 7

8. Parameter
Directionality
• Direction: OUT or INOUT or IN
• It specifies its direction with respect to the caller
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 8

9. Perspectives
of Class
Diagram
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka - OOAD 9

10. Focus of this course: Conceptual

11. Relationships
between
classes
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka - OOAD 11

12. Strength of
Relationships • Most weakest relationship: Dependency
• Most Strongest relationship: Inheritance
12
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD

13. Dependency
13
•A uses B
•Changing B will affect the A
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka - OOAD

14. Dependency
example
• Cart class depend on the Product class
• Cart uses Products
• Changing the Product will affect the Cart
• Cart class depends on the Product class
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 14

15. Associations
15
• Connects one instance of a class
with an instance of another class
• Stronger relationship than
Dependency
• An Employee works for a Company

16. Direction of Association
Unary Association vs Binary Association
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
16

17. Unary Associations
• Class A knows Class B
• Class B knows nothing about Class A
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
17

18. Unary Association
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 18

19. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
19

20. Binary Associations
• Class C knows about Class D
• Class D knows about Class C
• No arrow
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
20

21. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
21

22. Multiplicity
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
22

23. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
23

24. Reflective Association
• Objects in the same class can be associated
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
24

25. Association Class
This places the responsibility for maintaining information pertaining to
the association with the Ownership class.
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
25

26. Association Class -Example
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
26

27. Association Class -Example
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
27

28. Association Class -Activity
• Each Student can take multiple units
• A unit can be taken by many students
• Students who follow units can take exam multiple times if they fail
We need to manage their marks for each attempt in the system
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
28

29. Association Class -Activity
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
29

30. Aggregation - Association
• Whole-part relationship( “Part of” Relationship)
• Removing Class B will not affect to the Class A
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
30

31. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
31

32. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
32

33. Composition - Association
• ‘part’ depends on the ‘whole’
• Parts are destroyed when the whole is destroyed
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
33

34. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
34

35. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
35

36. Inheritance (or
Generalization)
• Represents an "is-a"
relationship.
• An abstract class name is
shown in italics.
• SubClass1 and SubClass2
are specializations of
SuperClass.
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 36

37. Realization
• Source class support all the
operations of the target
element
• Relationship between the
interface and the
implementing class
• Realization is a relationship
between the blueprint class
and the object containing its
respective implementation
level details.
IT1206 - Institute of Technology, University of Moratuwa Sameera Gunathilaka -
OOAD 37

38. IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
38

39. Thank you
IT1206 - Institute of Technology, University of Moratuwa
Sameera Gunathilaka - OOAD
39