Interaction modeling of Object Oriented Programming using Java.

2. Interaction Modeling
 Interaction modeling describes how the different elements in an
object model interact with each other. The term interacted is a set of
exchanged messages between the objects.
 The interaction model uses :-
Use case diagram
Sequence diagram
Activity diagram
Collaboration diagram

3. Use Case diagram
 A UML diagram that represents the relationship between actors and
use cases, and among the use cases.
 Represents an “architectural” view of the requirements.
 Actors :-
 External entities (e.g., user role, another system)
 Relationship between actors and use cases :-
 Initiation
 Communication
 Relationship among different use cases :-
 Enables the decomposition of complex use cases into smaller ones

4. Example of E-homework Use Case diagram
E-homework
distributionTeacher Students
E-homework
submission
E-homework
grading

5. Relationships in Use Case Model
 In UML, there are three kinds of relationships between
use cases :
Include Relationship
Extend Relationship
Generalization Relationship

6. Include Relationship
 Use case A includes use case B if the flow of events for A contains the flow of
events for B
 A whole-part relationship
 Allow use case A to access another common use case B
 In use case description
 At a particular point during the flow of events
Mention the inclusion at that point
 At any point in the flow of events
Mention the inclusion in the quality requirement
 In the use case diagram <<include>>

7. Example of Include Relationship
<<include>>
withdraw
Input
amount
Cancel
transaction
<<include>>
customer

8. Extend Relationship
 A use case A extends a use case B if the flow of events in A can occur amid
the flow of events in B when certain condition is true
 It is like an “interrupt”
 It is used to separate the exceptional behavior from the normal behavior
 Use case description
 Mentioned extension in the entry condition in the extending use case
 Specifying the condition that would trigger the extending use case
 Use case diagram
<<extend>>

9. Example of Extend Relationship
Connection
down
Deposit
withdraw
<<extend>>
<<extend>>
Name: connection down
…
Entry condition: This use case extends the Deposit and withdraw
use case. It is initialized by the system whenever the connection
between the customer and the central sever is lost.

10. Generalization Relationship
 It is a parent-child relationship between two or more use cause.
 It is a kind of relationship in which the properties of the parent use
case are inherited by the child use case.
 It can be represented as a directed arrow with a triangle as an arrow
head, as shown below :-

11. Example of Generalization Relationship
Account
Current
Account
Savings
Account
customer

12. Example of Use Case Diagram

13. Sequence Model
 Sequence Model represents the flow of system events,
actions, and messages between the objects over a time
period.
 A sequence model is of two types :
Scenario
Sequence diagram

14. Scenario
 A scenario is an instance of a use case showing a typical example of its
execution.
 Scenarios can be presented in UML using either sequence diagrams or
collaboration diagrams.
 Note that a scenario only describes an example of a use case, so
conditionality cannot be expressed!

15. Sequence Diagram
 A sequence diagram
depicts a scenario by
showing the
interactions among a
set of objects in
temporal order.
 Objects (not classes!)
are shown as vertical
bars. Events or
message dispatches are
shown as horizontal (or
slanted) arrows from
the sender to the
receiver.

16. Example of Sequence Diagram

17. Activity Diagram
 Describes how activities are coordinated.
 Is particularly useful when you know that an operation has to achieve a
number of different things, and you want to model what the essential
dependencies between them are, before you decide in what order to
do them.
 Records the dependencies between activities, such as which things can
happen in parallel and what must be finished before something else can
start.
 Represents the workflow of the process.

18. Activity Diagram Notation
Activity1() Activity2()
1. Activities
2. Transition

19. Activity Diagram Notation
Activity1()
[x>0]
[x=0]
[x<0]
[x>0]
[x=0]
[x<0]
3. Decision Diamond

20. Activity Diagram Notation
4. Join Bar 5. Fork Bar
6. Start Marker 7. Stop Marker

21. Activity Diagram Notation
Developers Testers Markers
Swimlane SwimlaneSwimlane
8. Swimlane

22. Activity Diagram of Library
Member Librarian
[borrower]
[returner]
Find book on shelf
Wait in queue
Prepare for next
member
Record borrowing
Record return
Put book back
on shelf
[returning]
[borrowing]

23. Collaboration Diagram
 Collaboration diagrams (called Communication diagrams) depict
scenarios as flows of messages between objects:

24. Example of Collaboration Diagram
 Collaboration Diagram of Library Management.