Barbara Liskov introduced her substitution principle back in 1987 during her keynote titled Data Abstraction and Heirarchy. Today, it is one of the five SOLID principles in object-oriented programming. “Instances of any type should be replaceable by instances of its subtypes without creating incorrect behaviors.” How can we ensure that our classes abide by the Liskov Substitution Principle?

Read more: http://www.runtime-era.com/2015/03/solid-review-liskov-substitution.html