How to Use Objects: Code and Concepts

Chapter 3. Abstraction and Hierarchy

The presentation so far has focused on objects and networks of objects. We ^1.1 have discussed how objects manage their internals and how they collaborate on larger tasks. We have also seen fundamental recurring structures and patterns one finds in practical applications. To achieve this focus on the runtime behavior, we have deliberately neglected classes and interfaces as the static, compile-time foundations of objects. When questions of inheritance did crop up in the context of method overriding, we have restricted the presentation to technical arguments. In the end, we were interested only in the result: ...