Creational Patterns

Last Updated: Dec 7, 2024

Creational patterns help manage and streamline object creation, making it more flexible, efficient, and suitable for various situations.

WARNING

I am only listing the ones that I've been dealing with or interact with a couple of times 😃

TL;DR

• Singleton: Ensures only one instance of a class exists and provides a global access point to it. Great for managing shared resources, like logging or configuration settings.
• Factory Method: Defines an interface for creating objects, letting subclasses decide the object type. Useful when you need to delegate creation to subclasses based on runtime conditions.
• Abstract Factory: Creates families of related objects without specifying concrete classes. Ideal for systems supporting multiple themes, platforms, or configurations.
• Builder: Separates complex object construction from its representation, allowing flexible and step-by-step creation. Handy for creating objects with many optional parameters.

Singleton Pattern

Definition

The Singleton Pattern is designed to ensure that only one instance exists and provides a global acces point to it. It is ideal for shared resources, such as configuration settings, logging, or managing connections.

Flow

• Instance Creation: When the application requests an instance of the Singleton, it checks if one already exists.
• Global Access: If an instance does not exist, it creates one. Subsequent requests return the same instance.
• Usage: Any part of the application can access the Singleton instance and interact with its methods or properties.

Factory Method Pattern

Definition

The Factory Method Pattern defines an inteface for creating objects, allowing subclasses to alter the type of objects created. This pattern is beneficial when the exact object type isn't known until runtime.

Flow

• Method Definition: A factory method is defined in a base class to create objects of a specific type.
• Subclass Implementation: Sublasses implement the factory method to produce different object types.
• Usage: The client calls the factory method without knowing the specific class of object it will recevive.

Abstract Factory Pattern

Definition

The Abstract Factory Pattern provides an interface to create families of related objects without specifying their concrete class.

Flow

• Factory Interface: An abstract factory defines methods for creating related products
• Concrete Factories: Implementations of the abstract factory create specific product variants.
• Usage: The client uses the factory interface to obtain product families without knowing the specific product classes.

Builder Pattern

Definition

The Builder Pattern lets us construct complex objects step by step. It’s useful for objects with multiple configurable fields or complex assembly processes.

Flow

• Builder Class: The builder class defines steps to create various parts of the object.
• Director (Optional): A director class can control the building process to create a specific configuration.
• Usage: The client uses the builder to construct an object by specifying only the desired properties.