SOLID — “L” Liskov Substitution Principle (LSP) Explained
Introduction to the Liskov Substitution Principle (LSP)
Understanding LSP
The Liskov Substitution Principle (LSP) is the “L” in the SOLID principles and is named after Barbara Liskov, who first introduced the concept in a 1987 conference keynote. The principle states that objects of a superclass should be replaceable with objects of a subclass without affecting the correctness of the program. In simpler terms, if class B is a subclass of class A, then wherever A is expected, B should be able to fit in without causing any errors or unexpected behavior.
LSP ensures that a subclass can stand in for its parent class without the client (the code that uses the classes) needing to know the difference. This principle is crucial for maintaining the integrity of object-oriented designs, particularly when extending systems with new functionality.
Why LSP is Important
Adhering to LSP allows for more flexible and maintainable code. It ensures that:
- Behavioral Consistency: Subclasses behave in a way that is consistent with what the client expects from the parent class.
- Code Reusability: Subclasses can be used interchangeably with their base…
