Ideal for working programmers new to Java, this best-selling book guides you through the language features and APIs of Java 21. Through fun, compelling, and realistic examples, authors Marc Loy, Patrick Niemeyer, and Dan Leuck introduce you to Java's fundamentals, including its class libraries, programming techniques, and idioms, with an eye toward building real applications.

This updated sixth edition expands the content to continue covering lambdas and streams, and shows you how to use a functional paradigm in Java. You'll learn about the latest Java features introduced since the book's fifth edition, from JDK 15 through 21. You'll also take a deep dive into virtual threads (introduced as Project Loom in Java 19).

This guide helps you:

• Learn the structure of the Java language and Java applications
• Write, compile, and execute Java applications
• Understand the basics of Java threading and concurrent programming
• Learn Java I/O basics, including local files and network resources
• Create compelling interfaces with an eye toward usability
• Learn how functional features have been integrated in Java
• Keep up with Java developments as new versions are released

Table of Contents

Chapter 1. A Modern Language

Chapter 2. A First Application

Chapter 3. Tools of the Trade

Chapter 4. The Java Language

Chapter 5. Objects in Java

Chapter 6. Error Handling

Chapter 7. Collections and Generics

Chapter 8. Text and Core Utilities

Chapter 9. Threads

Chapter 10. File Input and Output

Chapter 11. Functional Approaches in Java

Chapter 12. Desktop Applications

Chapter 13. Network Programming in Java

This book introduces the Java programming language and environment. Whether you are a software developer or just someone who uses the internet in your daily life, you’ve undoubtedly heard about Java. Its arrival was one of the most exciting developments in the history of the web, and Java applications continue to power business on the internet. Java is, arguably, the most popular programming language in the world, used by millions of developers on almost every kind of computer imaginable. Java has surpassed languages such as C++ and Visual Basic in terms of developer demand and has become the de facto language for certain kinds of development—especially for web-based services. Most universities are now using Java in their introductory courses alongside the other important modern languages. Perhaps you’re using this text in one of your classes right now!

This book gives you a thorough grounding in Java fundamentals and grammar. Learning Java, Sixth Edition, attempts to live up to its name by mapping out the Java language and its class libraries, programming techniques, and idioms. We’ll dig deep into interesting areas and at least scratch the surface of other popular topics. Other titles from O’Reilly pick up where we leave off and provide more comprehensive information on specific areas and applications of Java.

Whenever possible, we provide compelling, realistic, and fun examples and avoid merely cataloging features. The examples are simple but hint at what can be done. We won’t be developing the next great “killer app” in these pages, but we hope to give you a starting point for many hours of experimentation and inspired tinkering that will lead you to develop one yourself.

Who Should Read This Book

This book is for computer professionals, students, technical people, and Finnish hackers. It’s for everyone who has a need for hands-on experience using Java with an eye toward building real applications. This book could also be considered a crash course in object-oriented programming, threads, and user interfaces. As you learn about Java, you’ll also learn a powerful and practical approach to software development, beginning with a deep understanding of the fundamentals of Java.

Superficially, Java looks like C or C++, so you’ll have a tiny head start in using this book if you have some experience with one of these languages. If you do not, don’t worry. In many respects, Java acts like more dynamic languages such as Smalltalk and Lisp. Knowledge of another object-oriented programming language will certainly help, although you may have to change some ideas and unlearn a few habits. Java is considerably simpler than languages such as C++ and Smalltalk. If you learn well from concise examples and personal experimentation, you’ll like this book.

About the Author

Marc Loy is a senior software engineer and technical trainer specializing in user experience design and full stack development. He started working with Java in 1995 as a trainer with Sun Microsystems and has authored several books on Java, media production, and microcontroller development.

Patrick Niemeyer became involved with Java while working at Southwestern Bell Technology Resources. He is an independent consultant and author in the areas of decentralized applications and machine learning. Pat is the creator of BeanShell, a Java scripting language, and is a contributor to many open source projects. He currently works for Orchid Labs in San Francisco.

Dan Leuck is the CEO of Ikayzo, a Tokyo and Honolulu-based interactive design and software development firm with customers including Sony, Oracle, Nomura, PIMCO and the federal government. He previously served as Senior Vice President of Research and Development for Tokyo-based ValueCommerce, Asia's largest online marketing company, Global Head of Development for London-based LastMinute.com, Europe's largest B2C website, and President of the US division of DML. Daniel has extensive experience managing teams of 150+ developers in five countries. He has served on numerous advisory boards and panels for companies such as Macromedia and Sun Microsystems. Daniel is active in the Java community, is a contributor to BeanShell, the project lead for SDL, and sits on numerous Java Community Process expert groups.