Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
The Java Workshop

You're reading from   The Java Workshop Learn object-oriented programming and kickstart your career in software development

Arrow left icon
Product type Paperback
Published in Oct 2019
Publisher Packt
ISBN-13 9781838986698
Length 606 pages
Edition 1st Edition
Languages
Tools
Arrow right icon
Authors (3):
Arrow left icon
Eric Foster-Johnson Eric Foster-Johnson
Author Profile Icon Eric Foster-Johnson
Eric Foster-Johnson
Andreas Göransson Andreas Göransson
Author Profile Icon Andreas Göransson
Andreas Göransson
David Cuartielles David Cuartielles
Author Profile Icon David Cuartielles
David Cuartielles
Arrow right icon
View More author details
Toc

Table of Contents (20) Chapters Close

Preface 1. Getting Started 2. Learning the Basics FREE CHAPTER 3. Object-Oriented Programming 4. Collections, Lists and Java's Built-In APIs 5. Exceptions 6. Libraries, Packages, and Modules 7. Databases and JDBC 8. Sockets, Files, and Streams 9. Working with HTTP 10. Encryption 11. Processes 12. Regular Expressions 13. Functional Programming with Lambda Expressions 14. Recursion 15. Processing Data with Streams 16. Predicates and Other Functional Interfaces 17. Reactive Programming with Java Flow 18. Unit Testing Appendix

NullPointerException – Have No Fear

We presented the concept of null within Java in a previous chapter. As you may recall, null is the value that is implicitly assigned to an object upon creation, that is, unless you assign a different value to it. Related to null is the NullPointerException value. This is a very common event that can and will happen to you for a variety of reasons. In this section, we will highlight some of the most common scenarios of this in an effort to introduce you to a different way of thinking when dealing with any type of exception in your code.

In Example01, we examined the process of trying to perform operations on an object that was pointing to null. Let's look at some other possible cases:

public class Example04 {
    public static void main(String[] args) {
        String vehicleType = null;
        String vehicle = "car";
&...
lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at €18.99/month. Cancel anytime