🪨 SOLID Principles
Tags: solidprinciples, architecture, softwareengineering, designpatterns
Published: 2023-09-11 10:05:10

**SOLID Principles** are a set of five design principles in object-oriented programming and software engineering that aim to create robust, maintainable, and scalable software. They provide guidelines for writing clean, flexible, and modular code.

It is a meta acronym where each letter corresponds to another acronym:

- **SRP**: [Single Responsibility Principle](https://dev.to/amburi/solid-principles-single-responsibility-principle-srp-4bfm)
- **OCP**: [Open-Closed Principle](https://dev.to/amburi/solid-principal-open-closed-principle-ocp-doe)
- **LSP**: [Liskov Substitution Principle](https://dev.to/amburi/solid-principles-liskov-substitution-principle-lsp-1pco)
- **ISP**: [Interface Segregation Principle](https://dev.to/amburi/solid-principles-interface-segregation-principle-isp-bbf)
- **DIP**: [Dependency Inversion Principle](https://dev.to/amburi/solid-principles-dependency-inversion-principle-dip-1cpk)

---

{% embed https://dev.to/amburi/solid-principles-single-responsibility-principle-srp-4bfm %}

- **Definition**: A class should have only one reason to change, meaning it should have a single responsibility or job.
- **Goal**: Encourage modular and focused classes, making code easier to understand and maintain.
- **Advantages**: Improved maintainability, readability, and reusability; easier testing.
- **Disadvantages**: Over-applying SRP might lead to excessive class proliferation and complexity.

{% embed https://dev.to/amburi/solid-principal-open-closed-principle-ocp-doe %}

- **Definition**: Software entities should be open for extension but closed for modification.
- **Goal**: Enable adding new features without changing existing code, fostering extensibility.
- **Advantages**: Reduced risk of introducing bugs, better code organization.
- **Disadvantages**: Overly adhering to OCP can lead to complex designs.

{% embed https://dev.to/amburi/solid-principles-liskov-substitution-principle-lsp-1pco %}

- **Definition**: Objects of derived classes should be substitutable for objects of their base classes without affecting program correctness.
- **Goal**: Ensure behavioral consistency when using derived classes, supporting polymorphism.
- **Advantages**: Polymorphic behavior, easier maintenance.
- **Disadvantages**: Requires careful adherence, can be challenging to implement correctly.

{% embed https://dev.to/amburi/solid-principles-interface-segregation-principle-isp-bbf %}

- **Definition**: Clients should not be forced to depend on interfaces they do not use. Keep interfaces small and specific.
- **Goal**: Prevent classes from implementing unnecessary methods, reducing coupling.
- **Advantages**: Better code organization, improved reusability.
- **Disadvantages**: Can lead to more interfaces, requiring careful design.

{% embed https://dev.to/amburi/solid-principles-dependency-inversion-principle-dip-1cpk %}

- **Definition**: High-level modules should not depend on low-level modules; both should depend on abstractions. Abstractions should not depend on details; details should depend on abstractions.
- **Goal**: Reduce coupling, promote modular design, and allow for flexible system changes.
- **Advantages**: Reduced coupling, easier testing, improved maintainability.
- **Disadvantages**: May introduce complexity when designing abstractions.

---

## Wrap-Up!

SOLID principles offer guidelines to create well-structured and maintainable software. While they provide numerous advantages like better code organization, reusability, and extensibility, they may introduce complexity if applied excessively. Careful application of these principles can lead to more robust and adaptable software systems.