Book Image

The Java Workshop

By : David Cuartielles, Andreas Göransson, Eric Foster-Johnson
Book Image

The Java Workshop

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)

Delving into Recursion

Recursion is useful for many mathematical problems, such as when working with cellular automata, Sierpinski triangles, and fractals. In computer graphics, recursion can be used to help generate realistic-looking mountains, plants, and other natural phenomena. Classic problems, such as the Tower of Hanoi, work well with recursion.

In Java applications, you will often use recursion when traversing tree data structures, including XML and HTML documents.

Note

You can refer to https://packt.live/2JaIre8 for more information on the Tower of Hanoi problem.

A simple example of recursion looks like the following:

public int add(int num) {
    return add(num + 1);
}

In this example, each call to the add() method will call itself with a number that is one greater than the one used for the current call.

Note

You always need a termination condition to stop the recursion. This example does not have one.

Exercise 1: Using Recursion...