Book Image

Java 9 with JShell

By : Gaston C. Hillar
Book Image

Java 9 with JShell

By: Gaston C. Hillar

Overview of this book

The release of Java 9 has brought many subtle and not-so-subtle changes to the way in which Java programmers approach their code. The most important ones are definitely the availability of a REPL, known as JShell, which will make experiments and prototyping much more straightforward than the old IDE-based project-led approach. Another, more subtle change can be seen in the module system, which will lead to more modularized, maintainable code. The techniques to take full advantage of object-oriented code, functional programming and the new modularity features in Java 9 form the main subjects of this book. Each chapter will add to the full picture of Java 9 programming starting out with classes and instances and ending with generics and modularity in Java.
Table of Contents (23 chapters)
Java 9 with JShell
Credits
About the Author
Acknowledgement
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Combining class inheritance and interfaces


We can combine class inheritance with the implementation of interfaces. The following lines show the code for a new HideableWonderCat class that inherits from the WonderCat class and implements the Hideable interface. Note that the class declaration includes the superclass (WonderCat) after the extends keyword and the implemented interface (Hideable) after the implements keyword. The code file for the sample is included in the java_9_oop_chapter_08_01 folder, in the example08_07.java file.

public class HideableWonderCat extends WonderCat implements Hideable {
    protected final int numberOfEyes;

    public HideableWonderCat(String nickName, int age, 
        String fullName, int score, 
        int x, int y, int numberOfEyes) {
        super(nickName, age, fullName, score, x, y);
        this.numberOfEyes = numberOfEyes;
    }

    @Override
    public int getNumberOfEyes() {
        return numberOfEyes;
    }

    @Override
    public void show...