TITLE: - USECASE
DIAGRAM
THEORY:
USECASE
DIAGRAM:
A use case diagram is
a representation of a user’s interaction with the system that shows the
relationship between the user and the different use cases in which the user is
involved. It is a type of behavioral diagram. They are used to model the system
by including all the activities within a rectangle and focus on the actors
outside the system by interacting with it.
Use case models
consist of the following components:
·
Use case
·
Actor
·
Relationships like dependency,
generalization and association
·
Scenario
·
System Boundary
·
Use Case description
a) Use case
A Use Case is an
interaction between the system and a person or another system to achieve a
result. It describes the sequence of
actions which a system performs yielding visible results. It can be applied to
the whole system as well as a part of the system.
b) Actor
An actor represents
the roles of the users in use cases. It can be a person, a device or any
system.
Examples: student, customer,
bank, institution.
c) Relationships
It indicates the
semantic connection among elements, relationship between actors and use cases.
Relationships in use case are include and extend.
Include relationship
occurs when you have a chunk of behavior that is similar across more than one
use case. It is indicated as <<include>>.
Extend relationship
where you have one use case which adds functionality to another use case. It is
indicated as <<extend>>.
d) Scenario
It is a single path
through use case. Usually , use case is a collection of scenario.
e) System Boundary
It is the high level
indication of the domain
USECASE DIAGRAM
Scenario –I
An Automated Teller Machine (ATM)
Figure: Use Case Diagram for ATM
Scenario-II
Hospital
Management System
Figure: Use Case Diagram for
Hospital Management System
Scenario-III
Restaurant
Management System
Figure: Use Case Diagram for
Restaurant Management System
Here, use case diagram of Restaurant Management
System consist of four actors and five use cases and a system boundary. The
three actors are named as Customer, Cashier, Chef and Waiter. Here Customer
place the order and waiter receives order which is confirmed by the chef to
ready the order and cook the food, which is served by waiter to the customer
and customer eats the food and pay the bills and cashier accept the payment.
Discussion
and Conclusion
From
this lab session we got familiarized with the use case diagram, it represents
the user’s interaction with the system .It also shows the
relationship between the user and the different use cases in which the user is
involved.
Hence, from this lab session we have understood basic
knowledge about use case diagram.
