Book Image

Learn Java with Projects

By : Dr. Seán Kennedy, Maaike van Putten
5 (3)
Book Image

Learn Java with Projects

5 (3)
By: Dr. Seán Kennedy, Maaike van Putten

Overview of this book

Learn Java with Projects stands out in the world of Java guides; while some books skim the surface and others get lost in too much detail, this one finds a nice middle ground. You’ll begin by exploring the fundamentals of Java, from its primitive data types through to loops and arrays. Next, you’ll move on to object-oriented programming (OOP), where you’ll get to grips with key topics such as classes, objects, encapsulation, inheritance, polymorphism, interfaces, and more. The chapters are designed in a way that focuses on topics that really matter in real-life work situations. No extra fluff here, so that you get more time to spend on the basics and form a solid foundation. As you make progress, you’ll learn advanced topics including generics, collections, lambda expressions, streams and concurrency. This book doesn't just talk about theory—it shows you how things work with little projects, which eventually add up to one big project that brings it all together. By the end of this Java book, you’ll have sound practical knowledge of Java and a helpful guide to walk you through the important parts of Java.
Table of Contents (22 chapters)
1
Part 1: Java Fundamentals
9
Part 2: Object-Oriented Programming
15
Part 3: Advanced Topics

Understanding the differences between classes and objects

As classes and objects are integral to OOP, it is vital to understand their differences. We will discuss the relationship between a class and its objects in this section. As creating objects requires the use of the new keyword, this will also be covered. Understanding constructors and what they do will also be examined. All of these topics are linked: objects are the in-memory representation of the class (template); to create an object, a constructor is used and to call the constructor, we use the new keyword. Let’s examine these in turn.

Classes

A class is so integral in Java that you cannot write any program without defining one! A class is a blueprint or template for your object. It is similar to a plan of a house – using a house plan, you can discuss the house all you want; however, you cannot go into the kitchen and make a cup of tea/coffee. The house plan is abstract in that regard and so is the class...