High Cohesion and Low Coupling: Structured and Scalable Code

The principles of High Cohesion and Low Coupling (HC-LC) are pivotal for quality software development.

1. Understanding HC-LC 🧐

• High Cohesion (HC): Modules or classes should focus on a single responsibility, with closely related tasks grouped together.
• Low Coupling (LC): Aim for minimal dependencies between modules, promoting independence and flexibility.

2. Key Benefits of HC-LC 🚀

• Independent Modules: Changes in one module do not impact others, enhancing maintainability.
• Simplified Maintenance: Easier understanding and modifications of code.
• Effective Scalability: Effortlessly expand or modify programs.
• Improved Unit Testing: Isolated modules can be tested effectively.

3. Strategies for Implementing HC-LC 🎯

1. Define Clear Responsibilities: Each module/class should have a specific goal.
2. Utilize Abstractions and Explicit Dependencies: Use interfaces to limit direct dependencies.
3. Limit Communication: Keep interactions to a necessary minimum.
4. Apply Design Patterns: Use patterns like Mediator, Observer, or Façade to reduce direct dependencies.

4. Practical Example: HC-LC in JavaScript 🛠️

⚠️ Low Cohesion and High Coupling:

class Sistema {
  procesarDatos(datos) {
    // validation
    if(datos.length === 0) throw new Error("Sin datos");
    // direct database connection
    const db = new Database();
    db.guardar(datos);
  }
}

✅ High Cohesion and Low Coupling:

class ValidadorDatos {
  validar(datos) {
    if (datos.length === 0) throw new Error("Sin datos");
    return true;
  }
}

class DatabaseService {
  constructor(database) {
    this.database = database;
  }

  guardar(datos) {
    this.database.guardar(datos);
  }
}

class Sistema {
  constructor(validador, dbService) {
    this.validador = validador;
    this.dbService = dbService;
  }

  procesarDatos(datos) {
    if(this.validador.validar(datos)){
      this.dbService.guardar(datos);
    }
  }
}

// Independent implementation
const validador = new ValidadorDatos();
const dbService = new DatabaseService(new MySQLDatabase());
const sistema = new Sistema(validador, dbService);

sistema.procesarDatos(["dato1", "dato2"]);

This revised approach facilitates easier changes, testing, and future maintenance.

5. Additional Tips for HC-LC 📚

• Continuously refactor to enhance cohesion and reduce coupling.
• Focus on small, specialized modules.
• Regularly evaluate dependencies between components.

6. Conclusion: Continuous Improvement with HC-LC 🔍

Adhering to High Cohesion and Low Coupling principles is essential for developing robust, flexible, and scalable software. Regular application of HC-LC simplifies maintenance, expansion, and testing, ensuring each module has a clear responsibility with minimal interactions for exceptional results.