Pattern Design Creational Design Patterns 1

Question 1

Which creational pattern ensures only one instance of a class exists throughout the application lifecycle?

Accepted Answer

Singleton

Answer

The Singleton pattern restricts instantiation of a class to a single object and provides a global access point to it.

Question 2

The Factory Method pattern delegates object creation to:

Accepted Answer

Subclasses

Answer

Factory Method defines an interface for creating objects but lets subclasses decide which class to instantiate.

Question 3

Which pattern creates objects by copying an existing object?

Accepted Answer

Prototype

Answer

The Prototype pattern creates new objects by cloning an existing instance, avoiding the cost of creating objects from scratch.

Question 4

The Builder pattern is most useful when:

Accepted Answer

An object requires many optional parameters to construct

Answer

The Builder pattern separates the construction of a complex object from its representation, making it ideal for objects with many optional configuration steps.

Question 5

Abstract Factory differs from Factory Method in that it:

Accepted Answer

Creates families of related objects

Answer

Abstract Factory provides an interface for creating families of related or dependent objects without specifying their concrete classes.

Pattern Design Practice Test

Pattern Design Practice Test

Pattern Design Creational Design Patterns 1