Q-1). What is a Creational Design Pattern?
A-1). A Creational Design Pattern is a category of design patterns that deal with the mechanism of object creation. These patterns abstract the process of instantiating objects, making the system more flexible, scalable, and easier to manage by providing various ways to create objects. The main goal is to provide a way to decouple the client code from the concrete classes it uses, allowing the client to rely on interfaces or abstract classes.
Q-2). Name some Creational Design Patterns and their purposes.
A-2). The different types of Creational Design Patterns and their purposes are provided below:
Singleton Pattern
- Purpose: Ensures that a class has only one instance and provides a global point of access to that instance.
- Use Case: Managing shared resources like configuration settings, logging, thread pools, or database connections.
Factory Method Pattern
- Purpose: Defines an interface for creating objects, but allows subclasses to alter the type of objects that will be created.
- Use Case: When a class cannot anticipate the class of objects it must create, or to delegate the responsibility of instantiating subclasses.
Abstract Factory Pattern
- Purpose: Provides an interface for creating families of related or dependent objects without specifying their concrete classes.
- Use Case: When the system needs to be independent of how its products are created and represented, especially when dealing with multiple related product families.
Builder Pattern
- Purpose: Separates the construction of a complex object from its representation, allowing the same construction process to create different representations.
- Use Case: When creating complex objects with many optional parameters or when the construction process involves multiple steps.
Prototype Pattern
- Purpose: Creates new objects by copying an existing object (prototype), which acts as a template.
- Use Case: When object creation is expensive, a new object must be created by cloning an existing one rather than instantiating it from scratch.