Java Fundamentals

Chapter 5

OOP in Depth

Learning Objectives

By the end of this lesson, you will be able to:

• Implement interfaces in Java
• Perform typecasting
• Utilize the Object class
• Work with abstract classes and methods

Introduction

In the previous lesson, we looked at the basics of object-oriented programming, such as classes and objects, inheritance, polymorphism, and overloading.

We saw how classes act as a blueprint from which we can create objects, and saw how methods define the behavior of a class while fields hold the state.

We looked at how a class can acquire properties from another class through inheritance to enable us to reuse code. Then, we learned how we can reuse a method name through overloading – that is, as long as they have different ...