Book Image

The Java Workshop

By : David Cuartielles, Andreas Göransson, Eric Foster-Johnson
4 (2)
Book Image

The Java Workshop

4 (2)
By: David Cuartielles, Andreas Göransson, Eric Foster-Johnson

Overview of this book

Java is a versatile, popular programming language used across a wide range of industries. Learning how to write effective Java code can take your career to the next level, and The Java Workshop will help you do just that. This book is designed to take the pain out of Java coding and teach you everything you need to know to be productive in building real-world software. The Workshop starts by showing you how to use classes, methods, and the built-in Collections API to manipulate data structures effortlessly. You’ll dive right into learning about object-oriented programming by creating classes and interfaces and making use of inheritance and polymorphism. After learning how to handle exceptions, you’ll study the modules, packages, and libraries that help you organize your code. As you progress, you’ll discover how to connect to external databases and web servers, work with regular expressions, and write unit tests to validate your code. You’ll also be introduced to functional programming and see how to implement it using lambda functions. By the end of this Workshop, you’ll be well-versed with key Java concepts and have the knowledge and confidence to tackle your own ambitious projects with Java.
Table of Contents (20 chapters)

Overriding and Hiding Methods

When extending a class, it is possible to redefine some of the methods that are part of it. Overriding means to rewrite something's functionality. This is done by making a new declaration of the method with the same name and properties of the method from the original class. This is demonstrated in the following example. Note that we're continuing, for the sake of clarity, with Computer and Tablet, but they have been cleaned up so as not to make the example programs too long.

class Computer {
    public void whatIsIt() {
        System.out.println( "it is a PC");
    }
}
class Tablet extends Computer {
    public void whatIsIt() {
        System.out.println( "it is a tablet");
    }
}
class Example06 {
    public static void main(String[] args...