List-like Inheritance Hierarchy

In a list-like inheritance hierarchy each class possesses a maximum number of one subclass. Speculative generalization means that superclasses were implemented for a definitely required class in the hope that the created abstraction might come in handy later on.

Related smells: Speculative Hierarchy Speculative Generality

Reference

M. Lippert, S. Roock, “Refactoring in Large Software Projects: Performing Complex Restructurings Successfully”. John Wiley and Sons, 2006.