What is the Liskov Substitution Principle in software design?

What is the Liskov Substitution Principle in software design?

The Liskov Substitution Principle (LSP) states that objects of a superclass should be replaceable with objects of a subclass without affecting the correctness of the program.

Can you give me an example of this principle in action?

Sure! If you have a class Bird with a method fly(), and a subclass Penguin that cannot fly, substituting Penguin for Bird would violate LSP. Instead, you might create a FlyingBird subclass.

Why is this principle important in software design?

It's important because it promotes code reusability and maintainability. Following LSP ensures that subclasses can stand in for their parent classes without introducing errors.

What are some common violations of the Liskov Substitution Principle?

Common violations include methods that throw exceptions in subclasses or altering expected behavior, which can lead to unexpected results when substituting objects.