part a - wordpress.com ·  · 2016-09-07deployment diagram (ii).draw component and deployment...

18
Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 1 Year & Semester : III & VI Section : CSE 1 & 2 Subject Code : CS6502 Subject Name : OBJECT ORIENTED ANALYSIS AND DESIGN Degree & Branch : B.E (CSE) Staff in charge : Dr.B.VANATHI & Mr.K.SHANMUGAM UNIT 1-UMAL DIAGRAMS PART A Q.No. Question Competence Level 1 What is Object Oriented analysis & Design? Remembering BTL1 2 List the 4 phases in UP. Remembering BTL1 3 Compose your views on iterative Development and write it benefits. Creating BTL6 4 Define UML. Remembering BTL1 5 Define Class Diagram? When to use Class Diagrams? Remembering BTL1 6 Define UseCase. Analysing BTL4

Upload: dangngoc

Post on 02-Apr-2018

222 views

Category:

Documents


3 download

TRANSCRIPT

Page 1: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 1

Year & Semester : III & VI Section : CSE 1 & 2 Subject Code : CS6502

Subject Name : OBJECT ORIENTED ANALYSIS AND DESIGN Degree & Branch : B.E (CSE) Staff in charge : Dr.B.VANATHI & Mr.K.SHANMUGAM

UNIT 1-UMAL DIAGRAMS

PART – A

Q.No. Question Competence Level

1 What is Object Oriented analysis & Design? Remembering BTL1

2 List the 4 phases in UP. Remembering BTL1

3 Compose your views on iterative Development and write

it benefits.

Creating BTL6

4 Define UML. Remembering BTL1

5 Define Class Diagram? When to use Class Diagrams?

Remembering BTL1

6 Define UseCase. Analysing BTL4

Page 2: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 2

7 Point out the relationship used in Usecase. Applying BTL3

8 Discover the major Difference between Component and

Deployment Diagram.

Applying BTL3

9 Classify the 3 kinds of actors in usecase. Analysing BTL4

10 Define State Chart Diagram? When to use State

Diagram?

Remembering BTL1

11 Compare Activity and state chart diagram? Mention the

Elements of an Activity Diagram.

Evaluating BTL5

12 Define Aggregation and Composition.

Remembering BTL1

13 Differentiate between method and message in object. Understanding BTL2

14 Formulate the purpose of Interaction Diagram.

Creating BTL6

15 Analyze the need of State chart Diagram. Analysing BTL4

16 Discuss the Strength and Weakness of the Use case

Diagram.

Understanding BTL2

17 Interpret the meaning of event, state and Transition. Understanding BTL2

18 Give the use of Package Diagram. Understanding BTL2

19 Compare and Contrast of Sequence and Collaboration

diagram.

Evaluating BTL5

20 Illustrate the means of representing a node in a

Deployment Diagram.

Applying BTL3

Page 3: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 3

PART-B

Q.No. Question Competence Level

1 Explain in detail about the Unified process in object

oriented Analysis and Design? Explain the phases with

neat diagrams.

Analysing

BTL4

2

(i)Discuss about the Concepts of Component and

Deployment Diagram

(ii).Draw component and deployment diagrams for

Book bank system.

Understanding BTL2

3 A University conducts examinations and the results are

announced. Prepare a report for the following:

• Print the marks in the register number

order semester wise for each department

• Print the Arrear list semester wise.

• Prepare a Rank list for each department.

• Prepare the final aggregate mark list for

final year students.

Identify the problem statement and Design and

Explain the classes for each sequence. Draw a detailed

flow chart using state chart diagrams. Design this system

using Rational Rose. Draw all the UML diagrams for

designing this system.

Analysing BTL4

4

(i).Describe in detail about the Class Diagram.

(ii).What is use case Diagram? Model a use case diagram

for a Banking System. Explainthe business rules you are

considering. b) Consider the following use Cases that

play a role in the Banking System you have modeled: 1.

Deposit 2.Withdraw Model sequence diagrams for the

Remembering,

Analysing

BTL1

BTL4

Page 4: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 4

above two use cases.

5 Write a problem statement for Library Management

System. Design the UML Use Case diagram, Activity

diagram ,Class diagram, Sequence diagram, State chart

diagram,Package diagram, Component and Deployment

diagram.

Creating BTL6

6

List the various UML diagram and examine the purpose

of each diagram.

Remembering BTL1

7 (i)Describe the UML notation for Class diagram with an

example. Explain the concept of link, association and

inheritance.(12)

(ii).Identify the major difference between sequence and

collaboration diagram.(4)

Remembering BTL1

8 (i).Summarize with an example,how Interaction

Diagram are used to model the dynamic aspects of a

system.

(ii).Discuss the topic on

(i). Aggregation and Composition

(ii).Generalization and Specialization.

(iii).Attributes and Association

Understanding BTL2

9 (i).Illustrate about UML state machine diagram and

Modeling(8)

(ii).A Library lends books and magazines to member,

who is registered in the system. It also maintains the

purchase of new books and magazines for the Library. A

member can reserve a book or magazine that is not

currently available in the library, so that when it is

returned or purchased by the library, that person is

notified. The library can easily create, replace and delete

Applying BTL3

Page 5: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 5

information about the books, members, and reservation

in the system. The books transactions are stored in the

database. The fine list while the member returns the

book after the due date must be generated. Analyze and

discover the users and actors of this system, and the

interactions between them must be depicted.(8)

10

(i).Describe in Detail about the Sequence Diagrams.(6)

(ii).Discuss in detail about the three types of different

perspectives.(6)

(iii).Givethe three ways to apply Unified Modeling

Language (UML).(4).

Understanding BTL2

11

(i).What is UML activity diagram?Using an example

point out the features of basic UML activity diagram

notation. (8)

(ii).Draw and explain the Sequence and collaboration

diagram for an Online Purchase System. (8)

Remembering,

Analysing

BTL1

BTL4

12

(i).Explain with an example, how use case modeling is

used to describe functional requirements, Identify the

actors, scenario and use cases for the example.

(ii).Comparison between Activity and State chart

Diagram.

Evaluating BTL5

13.

(i).Describe UML Package diagram with example.

(ii).When to use Activity and State chart diagram?

Remembering BTL1

14 Illustrate about UML Deployment and Component

diagram with an example.

Applying BTL3

Page 6: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 6

UNIT II-DESIGN PATTERNS

PART – A

Q.No. Question Competence Level

1 Define GRASP. How to apply the GRASP patterns?

Remembering BTL1

2 Define responsibility. What are the various types of

responsibilities?

Remembering BTL1

3 List out the categories of Design patterns. Remembering BTL1

4 Define Design Pattern. State the use of design pattern. Remembering BTL1

5 When a pattern is said to be a good pattern? Remembering BTL1

6 Define creator. Remembering BTL1

7 Interpret the need of Information Expert. Understanding BTL2

8 Differentiate coupling and cohesion. Understanding BTL2

9 Express the benefits of low coupling. Understanding BTL2

10 Analyze the meaning of coupling and also analyze its

types.

Analysing BTL4

11 “ A system must be loosely coupled and highly cohesive”-

Justify.

Evaluating BTL5

12 Compose your views on High Cohesion. Creating BTL6

13 Examine the benefits of controller. Applying BTL3

14 Discuss the benefits and the types of adapter pattern. Understanding BTL2

15 Summarize the list of structural patterns used during

design phase of software development.

Evaluating BTL5

Page 7: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 7

16 Analyze the situation to use Factory method pattern and

its advantages.

Analysing BTL4

17 Discover the Limitations of Factory Pattern Applying BTL3

18 Illustrate the benefits of bridge pattern. Applying BTL3

19 Generalize your view on Modular Design. Creating BTL6

20 Point out the benefits of strategy pattern. Analysing BTL4

PART-B

Q.No. Question Competence Level

1 Explain GRASP:Designing objects with responsibilities. Analysing BTL4

2 What isGRASP? Describe the design patterns and

principles used in it.

Remembering BTL1

3 Examine the following GRASP patterns:

(i)Creator,(4)

(ii).Information Expert, (4)

(iii)Low coupling, (4)

(iv).High cohesion(4)

Remembering BTL1

4 (i).Explain about Creator and information Expert with

example.(10)

(ii).Explain the Benefits of Low coupling and difficulties

of Low cohesion.(6)

Analysing BTL4

5 (i)

(ii)

Compare cohesion and coupling with suitable example.

(8)

Summarize and state the role and patterns while

developing system design. (8)

Evaluating BTL5

Page 8: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 8

6 (i).Generalize your idea onController pattern with

example

(ii).Generalize the concepts of Façade, session and

bloated controller.

Creating BTL6

7 (i).Discuss about Low Coupling and High Cohesion with

example.

(ii).Describe the different scenarios of functional

cohesion.

Understanding BTL2

8 (i).Givean account on Factory method.

(ii).Discuss the topic on coupling and mention its types.

Understanding BTL2

9 (i)

(ii)

Differentiate Adapter and Bridge pattern .(8)

Analyze how willyou design the behavioral pattern.(8)

Analysing BTL4

10 Discuss the topic on

(i).Adapter Pattern

(ii). Observer Pattern

(ii).Factory Pattern

Understanding BTL2

11 (i).Describe about Strategy pattern.(10)

(ii).List out the applications of Factory pattern and

mention its Limitations.(6)

Remembering

BTL1

12 (i).Examine in detail about Behavioral pattern.

(ii).Describe the concepts of Singleton Pattern.

Remembering BTL1

13 Demonstrate in detail about the various categories of

Design pattern.

Applying BTL3

14 (i).Illustrate your views about Structural patterns.(8)

(ii).What is Visibility? Classify the ways of visibility and

explain it.(8)

Applying BTL3

Page 9: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 9

UNIT III-CASE STUDY

PART – A

Q.No. Question Competence Level

1 What is a POS system? List the components of POS

system.

Remembering BTL1

2 List out the advantages of Use case Modeling. Remembering BTL1

3 List out the Components of Domain model? Remembering BTL1

4 Distinguish abstract use case and concrete Use Case. Analysing BTL4

5 Express the meaning of Elaboration and What are the

tasks performed in elaboration?

Understanding BTL2

6 Difference between Include and Extend use case

relationships.

Analysing BTL4

7 Define Domain Model. Remembering BTL1

8 Demonstrate how to create a Domain model. Applying BTL3

9 Express why we call a domain model

a“VisualDictionary".

Understanding BTL2

10 Define Conceptual class. Remembering BTL1

11 Compare Aggregation and Composition.

Evaluating BTL5

12 Illustrate the usage of Description class. Applying BTL3

13 Generalize the purpose of association relationship. Creating BTL6

14 Show the important deals in Inception of the POS system?

Mention the requirements of Inception phase of the POS

Applying BTL3

Page 10: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 10

system.

15 Define attribute? List out the types of attributes.

Remembering BTL1

16 Interpret the meaning of Generalization and

specialization.

Understanding BTL2

17 Give the meaning of abstract conceptual class. Understanding BTL2

18 How to create Domain model? Creating BTL6

19 Compare qualified association and reflexive association. Evaluating BTL5

20 Point out the main goals of Establishing conceptual class

Hierarchies.

Analysing BTL4

PART-B

Q.No. Question Competence Level

1 (i).What is a POS system? Briefly explain about

Inception Phase.

(ii). Comparison between Association and attributes.

Analysing BTL4

2 Prepare a suitable example showing the various

relationships used in Use Case and also give a short note

on each relationship.

Creating BTL6

3 (i).Summarize the Elaboration phase.

(ii).Discuss the difference between elaboration and

inception with example.

Understanding BTL2

4 (i).Describe the strategies used to identify the conceptual

classes.

(ii).Describe the steps to create adomain model used for

representing the conceptual classes.

Understanding BTL2

Page 11: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 11

5

(i).Illustrate the concepts of Domain model with

example.

(ii).Show when to model with Description classes with

example.

Applying BTL3

6

(i).Summarize the steps and explain how to find Use

cases with an example.

(ii).Rank the 3 kinds of actors and explain the 3

common Use Case formats.

Evaluating BTL5

7 (i).Describe briefly about association and formulate the

guidelines to be followed with UML with suitable

example.

(ii).Describe the concepts of Derived attribute.

Remembering BTL1

8 (i).Discuss about attributes with example.

(ii).Discuss the topic on

a).Coceptual subclass

b)Conceptual super class

c) Multiplicity

Understanding BTL2

9 (i).Explain in detail about domain Model refinement.

(ii).What is use cases and Explain in detail about the

sample Unified process Artifacts Relationships.

Analysing BTL4

10 (i).Analyze the guidelines to define a conceptual subclass

with suitable example.

(ii). Analyze the guidelines to define a conceptual super

class with suitable example.

Analysing BTL4

11 (i).What are the guidelines used to partition the classes in

the domain model to be organized into packages? Explain

with suitable examples.

(ii).Describe the benefits of composition.

Remembering BTL1

Page 12: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 12

12

(i).Examine the various sections in the Use Case template

with example.

(ii).List the guidelines to be followed when writing Use

Case.

Remembering BTL1

13 (i).Describein detail about the Finding Conceptual class

Hierarchies.

(ii).Describe briefly about association classes and

association role.

Remembering BTL1

14 (i).Illustrate about aggregation and composition with

example. Mention the guidelines to be followed.

(ii). Illustrate the topic on

(i). Generalization

(ii). Specialization

(iii). Conceptula class hierarchies.

Applying BTL3

UNIT IV-APPLYING DESIGN PATTERNS

PART – A

Q.No. Question Competence Level

1 Express the use of Sequence Diagram. Understanding BTL2

2 Distinguish sequence diagram and communication

diagram.

Understanding BTL2

3 Demonstrate what do you mean by sequence number in

UML? Where and for what it is used?

Applying BTL3

4 What is meant by System Behavior? Remembering BTL1

5 Define Package. Draw UML notation for Package. Remembering BTL1

6 Analyze the use of UML Package Diagram Analysing BTL4

Page 13: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 13

7 Define Logical architecture. Remembering BTL1

8 Formulate the guideline to be followed when designing

with layers.

Creating BTL6

9 List the layers of architectural layers. Remembering BTL1

10 Differentiate strict layered and relaxed layered

architecture.

Understanding BTL2

11 Summarize the Model View separation principle. Evaluating BTL5

12 List the common UML Interaction diagram notation. Remembering BTL1

13 Name the layers in the 3 tier architecture. Remembering BTL1

14 Show the relationship between Interaction and Class

diagram with example.

Applying BTL3

15 Express the meaning of Facade. Understanding BTL2

16 Differentiate Class diagram and Interaction diagram. Analysing BTL4

17 Illustrate the term Classifier. Applying BTL3

18 Create SSD for Borrow book scenario. Creating BTL6

19 Summarize the benefits of using layers. Evaluating BTL5

20 Compare and Contrast asynchronous and synchronous

message.

Analysing BTL4

PART-B

Q.No. Question Competence Level

1 (i).Illustrate the relationship between sequence diagram

and Use Case with example.

(ii).Demonstrate the Interaction Diagram notations and

explain it?

Applying BTL3

2 (i).Describe briefly about the logical architecture and

UML package diagram.

Remembering BTL1

Page 14: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 14

(ii).Identify the relationship between Domain layer and

Domain model.

3 What is Model View separation principle? Examine the

motivation for Model View separation.

(ii).Describe the concepts of Dependency relationship.

Remembering BTL1

4 (i).What are the benefits of using layers? Provide the

relationship between Domain layer and Domain model.

(ii).Describe the concepts of Relaxed layer coupling.

Remembering BTL1

5 (i).Briefly discuss about the various collaborations with

the layers.

(ii).Discuss in detail about Logical Architecture

refinement.

Understanding BTL2

6 .

(i).Give short notes on inter layer and inter package

coupling.

(ii).Discuss on the classic 3 tier architecture.

Understanding BTL2

7

(i).Describe how to adding a new System sequence

diagram and contracts?

(ii).Describe the UML notation for class diagram with an

example.Explain the concept of Link,Association and

Inheritance.

Understanding BTL2

8 (i).Examine with an example about Interaction diagram.

(ii).Explain with the example,Illustrate how interaction

diagram are used to model the dynamic aspects of the

system.

Applying BTL3

9 (i).Explain about Interaction diagram notation for

Inventory Management System.

(ii).Explain in detail about UML package Diagram.

Analysing BTL4

Page 15: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 15

10 (i).Compare sequence diagram and communication

diagram with suitable example.

(ii).Explain the Concepts of frames in UML.

Evaluating BTL5

11 Briefly explain about UML sequence diagram notations

with example.

Analysing BTL4

12 What is design pattern? Describe the GOF design

patterns.

Remembering BTL1

13 Generalize your views and write notes on Structural and

Behavioral Pattern.

Creating BTL6

14 With an example explain notations used in sequence

diagram for the following:

(i).Object destruction (3),

(ii).Frames (3),

(iii).Conditional message(3),

(iv).Mutually exclusive conditional message(3),

(v).Iterations over a collection (4).

Analysing BTL4

UNIT V-CODING AND TESTING

PART – A

Q.No. Question Competence Level

1 What are the steps for mapping design to code? Remembering BTL1

2 What is TDD? Remembering BTL1

3 Give theadvantages of test driven development. Understanding BTL2

4 Define refactoring. Remembering BTL1

5 List the activities and goals of refactoring. Remembering BTL1

6 Summarize the issues in OO testing. Understanding BTL2

Page 16: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 16

7 Summarize class testing. Evaluating BTL5

8 Conclude on the need of Integration testing. Evaluating BTL5

9 Generalize the need of GUI testing. Creating BTL6

10 Analyze the need for OO system testing. Analysing BTL4

11 Differentiate OO integration testing and OO system

testing.

Understanding BTL2

12 Point out the meaning of unit. Analysing BTL4

13 List the 2 levels of Integration testing.

Remembering BTL1

14 Examine on static view, compile time view and execution

time view on classes.

Applying BTL3

15 Illustrate about Unit testing. Applying BTL3

16 Point out the use of atomic system function (ASF). Analysing BTL4

17 Interpret the use of method/message path (MM-path).

Understanding BTL2

18 Design the 4 controls commonly used in GUI design. Creating BTL6

19 List the 3 types of system function. Remembering BTL1

20 Point out the 4 levels with coverage metrics for GUI

application.

Applying BTL3

PART-B

Q.No. Question Competence Level

1 Explain in detail about mapping design to code concepts

in detail.

Analysing BTL4

2 (i).Describe in detail about coding and testing in OOAD.

(i).Describe about the implementation model (Mapping

design to code) and give the NextGen POS program

solution.

Remembering BTL1

Page 17: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 17

3 (i).Discuss in detail about the different types of testing in

OOAD.

(ii).Describe the two views of OO unit testing.

Understanding BTL2

4 (i).Discuss briefly about the issues in OO testing.

(ii).Describe the two levels of integration in OO

integration testing.

Understanding BTL2

5 (i).What is OO testing?

(ii).Examine in detail about the concepts of OO testing in

OOAD.

Remembering BTL1

6 (i).Briefly summarize about class testing.

(ii).Explain the implications of composition and

Encapsulation.

Evaluating BTL5

7 (i).Illustrate about OO Integration testing with example.

(ii). Illustrate the Unit testing concepts by using Currency

Conversion program.

Applying BTL3

8 (i).Demonstrate the need for GUI testing. Applying BTL3

9 (i).Describe about OO system testing.

(ii). Describe the concepts of Event and Message Driven

petri Nets(EMDPNs)

Remembering BTL1

10 (i).Compare and contrast OO integration testing and OO

system testing.

(ii).Explain the implication of inheritance.

Analysing BTL4

11 (i).Differentiate GUI testing and class testing.

(ii).Explain the three types of system functions in OO

system testing.

Analysing BTL4

12 (i).Examine theframework for OO data flow integration

testing.

(ii).Describe the concepts of UML based system testing.

Remembering BTL1

13 Discuss on

(i) Methods as units (8)

Understanding BTL2

Page 18: PART A - WordPress.com ·  · 2016-09-07Deployment Diagram (ii).Draw component and deployment diagrams for ... .What is use case Diagram? Model a use case diagram for a Banking System

Dr.B.VANATHI & Mr.K.SHANMUGAM CS 6502-OOAD Page 18

(ii)Classes as units (8)

14 (i).Use currency converter application as example and

generalize the steps in OO system testing.

(ii). Generalize the concepts of implications in

Polymorphism.

Creating BTL6