Abstraction: Amplify The Essential Eliminate The Irrelevant

Introduction

A computer program is a model of a real-world problem. But real-world problems are notoriously complex. It is impossible to capture all the details and nuances of a real-world problem in software. However, it is possible to study a real-world problem closely, identify its important points or components, and then create new software data types that represent the essential features or elements of these components. The process of selecting the essential elements of a problem with an eye towards modeling them in software is referred to as problem abstraction.

This chapter shows you how to approach the process of problem abstraction. Along the way you will learn more about Java classes, methods, fields, Unified Modeling Language (UML) class diagrams, and object-oriented programming. You will learn how to break functionality into logical groups to formulate methods. These methods will provide a measure of code reuse that will save you both work and time.

The material discussed here builds upon that presented in previous chapters. By now you should be very comfortable with your integrated development environment or the Java SDK. You should be able to create simple Java programs, control the flow of program execution with if, if/else, for, while, and do/while statements, and you should understand the concepts and use of single-dimensional arrays. You should also be getting pretty good at looking through the Java API for classes that can help you solve problems.

Upon completion of this chapter you will have added several powerful tools to your programmer’s toolbag. These tools will enable you to write increasingly complex programs with ease.