SOLID: los principios de la programación orientada a objetos

Figuras IsometricasEn la universidad es descubierto que existen los principios básicos de la programación orientada a objetos, llamada SOLID, que es el acrónimo de una serie de buenas prácticas:

  • SRP (The Single Responsibility Principle o Principio de Responsabilidad Única): una clase debe tener una, y solamente una, razón para cambiar.
  • OCP (The Open/Closed Principle o Principio Abierto / Cerrado): una clase debe permitir ser extendida, sin necesitar ser modificada.
  • LSP (The Liskov Substitution Principle o Principio de Sustitución de Liskov): las clases derivadas deben poder ser sustituibles por sus clases base.
  • ISP (Interface Segregation Principle o Principio de Segregación de Interfaces): hacer interfaces de grano fino que son específicos de clientes.
  • DIP (The Dependency Inversion Principle o Principio de Inversión de Dependencias): las abstracciones no deben depender de los detalles, los detalles deben depender de las abstracciones.

El principio que más me impacto fue el principio de Open/Close, ya que lo veo como el más importante de los cinco, al ser el que da la potencia a la programación orientada a objetos. Software abierto a ser extensible, y cerrado a ser modificado. Esa mentalidad de desarrollar el software de manera que sea extensible sin modificarlo, se consigue utilizando la herencia, el polimorfismo, la modularidad, el encapsulamiento, abstracción,… es decir, la características fundamentales de la POO.

Ahora que estoy profundizando en Zend Framework, veo más claramente que el objetivo final es la reutilización de código fiable, de manera que no se pierda el tiempo ni volviendo a construir la rueda, ni comprobando la solidez de la rueda.

Para interesados, existen 6 principios más, sobre la relación de las clases para formar paquetes o package, y la relación entre package.

Fuentes – Climens Codelog, Bucle Infinito y Butunclebob.

25 comentarios en “SOLID: los principios de la programación orientada a objetos

  1. hola nesecito ayuda para clases de sql server 2008, y
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