Kas saaksite selgitada SOLID põhimõtteid ja kuidas neid rakendatakse tarkvarasüsteemide kavandamisel?

SOLID is a set of five object-oriented design principles that help create flexible and maintainable systems:

• S (Single Responsibility Principle) — a class should have only one responsibility.
• O (Open/Closed Principle) — software entities should be open for extension, but closed for modification.
• L (Liskov Substitution Principle) — objects of a subclass should be replaceable with objects of the superclass without affecting the correctness of the program.
• I (Interface Segregation Principle) — it is better to have several specific interfaces than one general interface.
• D (Dependency Inversion Principle) — high-level modules should not depend on low-level modules; both should depend on abstractions.

Applying these principles allows creating code that is easier to test, extend, and maintain. For example, separating responsibilities helps avoid bulky classes, and using interfaces makes component replacement easier without changing the rest of the code.