Learning Java, 7th Edition

Chapter 5. Chapter 5. Objects in Java

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In this chapter, we get to the heart of Java and explore its object-oriented aspects. The term object-oriented design (OOD) refers to the art of decomposing an application into some number of objects, which are self-contained application components that work together. The goal is to break your problem down into smaller problems that are simpler and easier to handle and maintain. Object-based designs have proven themselves over the years, and object-oriented languages such as Java provide a strong foundation for writing applications—from the very small to the very large. Java was designed from the ground up to be an object-oriented language, and all of the Java APIs and libraries are built around solid object-based design patterns.

An object-design methodology is a system or a set of rules created to help you break down your application into objects. Often this means mapping real-world entities and concepts (sometimes called the problem domain) into application ...