Design patterns are reusable solutions to common software design problems. They are general templates or blueprints that provide guidance on how to structure and organize code to address specific software design challenges. Design patterns help software developers create code that is more maintainable, flexible, and robust by promoting best practices and established solutions.
Design patterns are not specific implementations or libraries but rather high-level concepts that can be applied to various programming languages and paradigms. They were popularized by the book “Design Patterns: Elements of Reusable Object-Oriented Software,” written by Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides, often referred to as the “Gang of Four” (GoF). This book introduced 23 classical design patterns, categorized into three groups:
- Creational Patterns: These patterns focus on object creation mechanisms, trying to create objects in a manner suitable for the situation. Examples include the Singleton, Factory Method, Abstract Factory patterns, Builder And Prototype Pattern.
- Structural Patterns: Structural patterns deal with object composition, defining relationships between objects to form larger, more complex structures. Examples include the Adapter, Decorator, Composite , Proxy, Flyweight, Facade and Bridge Patterns
- Behavioral Patterns: Behavioral patterns are concerned with communication between objects and how they operate together to achieve common tasks. Examples include the Observer, Strategy, Command, Template Method, Mediator, Chain of Responsibility, State, Visitor, Iterator, Interpreter and Memento Patterns.
Each design pattern addresses a specific problem and provides a standardized way to solve it. They are not strict rules but rather guidelines that developers can adapt to their specific project requirements. Applying design patterns can lead to code that is more modular, easier to understand, and less prone to errors. However, it’s essential to use them judiciously, as overusing patterns can lead to overly complex code.
In addition to the original 23 GoF design patterns, many other design patterns have emerged over the years to address various software development challenges. Developers often study and use these patterns to improve the quality and maintainability of their software projects.
We will discuss each one of the Patterns in the upcoming posts.