Gson: Enjoy JSON (De-)Serialization in Java (eBook & Workbook)
Gson: Enjoy JSON (De-)Serialization in Java
About the Book
Learn Every Detail About Gson
Every modern Java application will need to do some Java-JSON parsing in their application life cycle. Gson is the most commonly used library to do the Java-JSON serialization and deserialization automatically.
Data parsing and mapping is complex. Even though Gson makes things quite simple, there are a lot of details that can trip your development up. If it's crazy data structures, weird variable names or complex dynamic data, you can lose a lot of time on something that should be done in minutes. Gson solves most problems in just a few lines. You just need to know the solutions!
This book includes an extensive introduction to Gson's features. We recommend to read it before you even have to use Gson for the first time. But even if you're already an avid user of Gson and stuck at a problem, we're confident we'll solve your problem.
Use our extensive bundle to learn about:
- Introduction to JSON & JSON-Java mapping
- Quick start to jump right into Gson
- Mapping of any Java type
- Deep dive into Gson's configuration options
- Practical examples of Gson customization
- Even advanced topics (Streaming, Generics, ...) are covered
- Necessary ProGuard configuration for Android app releases
Additionally, you'll get an extensive appendix:
- Combining a customized Gson with Retrofit 2
- Overview over common mistakes
- Exploration of Gson alternatives
Who Is This Book For?
This book is for Android or Java developers who want to get a substantial overview and reference book for Gson. You’ll benefit from the clearly recognizable code examples in regard to your daily work with Gson.
Rookie
If you’re just starting out with Gson (or coming from any other Java-JSON library like Jackson databind) this book will show you all important parts on how to work with Gson. The provided code snippets let you jumpstart and create the first mapping within minutes.
Expert
You already worked with Gson before? You’ll profit from our extensive code snippets and can improve your existing code base. Additionally, the book illustrates various optimizations for an even better performance.
Code Samples
Every code snippet in the book has been tested. We provide our test project as a leanpub extra. Feel free to download it and check the full code base as you move through the book. We try to keep the code snippets in the book as short as possible. If more context is necessary, the code examples should provide it.
Workbook
For the first time, we provide additional separated resources besides our book. The workbook gives you a chance to implement everything you'll learn in this book yourself. In our experience actually using a library like Gson helps to reinforce the newly gained knowledge. Thus, we've designed the workbook, which gives you a guided playground to experiment and learn the features of Gson.
Packages
eBook & Workbook
Includes:
Gson Sample Code
Code snippets of the book in action as an Android project.
PDF
EPUB
WEB
English
Just The eBook
Includes:
Gson Sample Code
Code snippets of the book in action as an Android project.
PDF
EPUB
WEB
English
Bundles that include this book
About the Contributors
Christian is an experienced Software Engineer and consultant working with a wide variety of companies, ranging from startups to Fortune 500 companies.
His experiences range across a number of fields and technologies, including web and game development, virtual reality and machine learning.
Christian is an all-round nerd, passionate about outstanding design and creating innovational user experiences.
He has given training to many developers and students since 2011; explaining state of the art technologies and project management methodologies.
Christian has a BSc degree in Computer Systems in Engineering from the Otto von Guericke University Magdeburg.
Find him on Twitter: @celsiusF.

Marcus is an enthusiastic Android & Java developer. He’s developed multiple production-ready client and server applications. While following the core principle of performance for client apps, he also builds REST+JSON APIs that focus on clear and consistent design.
Besides his day job, sharing knowledge and teaching others has become a characteristic he never wants to miss.
Marcus has a Master’s degree in computer science from the Otto von Guericke University Magdeburg.
Feel free to get in touch on Twitter @marcuspoehls.
Table of Contents
-
About the Book
- What Topics Are Covered in This Book?
- Who Is This Book For?
- Code Examples
- Workbook
-
Chapter 1 — Introduction to Java-JSON Mapping
- Adding Gson as Dependency
- Basics of Java-JSON Serialization
- Basics of Java-JSON Deserialization
-
Chapter 2 — JSON Mapping with Gson
- Mapping of Nested Objects
- Mapping of Arrays and Lists of Objects
- Mapping of Maps
- Mapping of Sets
-
Mapping of
Null
Values
-
Chapter 3 — Gson Model Annotations
- How to Ignore Fields
- How to Adjust the Naming of Fields
-
Multiple Deserialization Names with
@SerializedName
-
Chapter 4 — Configuring Gson with GsonBuilder
- GsonBuilder Basics
- Naming Policies
-
Force Serialization of
null
Values -
Go Beyond
transient
and@Expose
with Exclusion Strategies - Relax Gson with Lenient
- Special Values of Floats/Doubles
- Model Versioning
- Formatting of Dates & Custom Date/Time Mapping
- Pretty Printing
- HTML Escaping
-
Chapter 5 — Advanced Gson Usage
- Mapping of Enums
- Mapping of Circular References
- Mapping of Generics
- Custom Serialization for Simplification (Part 1)
- Changing the Default Serialization with Custom Serialization (Part 2)
- Custom Deserialization Basics
- Custom Instance Creator
- Customizing (De)Serialization via @JsonAdapter
- Custom Deserialization for Calculated Fields
- On-The-Fly-Parsing With Streams
-
Chapter 6 — ProGuard Configuration
- Gson and ProGuard Are Not Best Friends
- Standard Gson Configuration
-
Chapter 7 — Practical Gson
- Low Level Parsing
- Storing Data in Android’s SharedPreferences With Gson
- How to Deserialize a List of Polymorphic Objects
-
Chapter 8 — Appendix
- Gson’s Configuration for Retrofit 2
- 5 Common Mistakes & Issues
- Overview of Alternatives
-
Outro
- Workbook
-
Future Studio Books
- Retrofit
- Picasso
- Glide
- Future Studio Bundle
The Leanpub 60-day 100% Happiness Guarantee
Within 60 days of purchase you can get a 100% refund on any Leanpub purchase, in two clicks.
See full terms
80% Royalties. Earn $16 on a $20 book.
We pay 80% royalties. That's not a typo: you earn $16 on a $20 sale. If we sell 5000 non-refunded copies of your book or course for $20, you'll earn $80,000.
(Yes, some authors have already earned much more than that on Leanpub.)
In fact, authors have earned$12,046,757writing, publishing and selling on Leanpub.
Learn more about writing on Leanpub
Free Updates. DRM Free.
If you buy a Leanpub book, you get free updates for as long as the author updates the book! Many authors use Leanpub to publish their books in-progress, while they are writing them. All readers get free updates, regardless of when they bought the book or how much they paid (including free).
Most Leanpub books are available in PDF (for computers) and EPUB (for phones, tablets and Kindle). The formats that a book includes are shown at the top right corner of this page.
Finally, Leanpub books don't have any DRM copy-protection nonsense, so you can easily read them on any supported device.
Learn more about Leanpub's ebook formats and where to read them
Top Books
OpenIntro Statistics
David Diez, Christopher Barr, Mine Cetinkaya-Rundel, and OpenIntroA complete foundation for Statistics, also serving as a foundation for Data Science.
Leanpub revenue supports OpenIntro (US-based nonprofit) so we can provide free desk copies to teachers interested in using OpenIntro Statistics in the classroom and expand the project to support free textbooks in other subjects.
More resources: openintro.org.
Mastering STM32 - Second Edition
Carmine NovielloWith more than 1200 microcontrollers, STM32 is probably the most complete ARM Cortex-M platform on the market. This book aims to be the most complete guide around introducing the reader to this exciting MCU portfolio from ST Microelectronics and its official CubeHAL and STM32CubeIDE development environment.
C++20 - The Complete Guide
Nicolai M. JosuttisAll new language and library features of C++20 (for those who know previous C++ versions).
The book presents all new language and library features of C++20. Learn how this impacts day-to-day programming, to benefit in practice, to combine new features, and to avoid all new traps.
Buy early, pay less, free updates.
Other books:
Jetpack Compose internals
Jorge CastilloJetpack Compose is the future of Android UI. Master how it works internally and become a more efficient developer with it. You'll also find it valuable if you are not an Android dev. This book provides all the details to understand how the Compose compiler & runtime work, and how to create a client library using them.
Talking with Tech Leads
Patrick KuaA book for Tech Leads, from Tech Leads. Discover how more than 35 Tech Leads find the delicate balance between the technical and non-technical worlds. Discover the challenges a Tech Lead faces and how to overcome them. You may be surprised by the lessons they have to share.Functional Event-Driven Architecture
Gabriel VolpeExplore the event-driven architecture (EDA) in a purely functional way. Learn to design and develop distributed systems that scale. Identify common design patterns in such systems.
Take your functional programming skills to the next level by joining me in developing a distributed system powered by Apache Pulsar and Fs2 streams, all in Scala 3!
Machine Learning Q and AI
Sebastian Raschka, PhDHave you recently completed a machine learning or deep learning course and wondered what to learn next? With 30 questions and answers on key concepts in machine learning and AI, this book provides bite-sized bits of knowledge for your journey to becoming a machine learning expert.
Getting to Know IntelliJ IDEA
Trisha Gee and Helen ScottIf we treat our IDE as a text editor, we are doing ourselves a disservice. Using a combination of tutorials and a questions-and-answers approach, Getting to Know IntelliJ IDEA will help you find ways to use IntelliJ IDEA that enable you to work comfortably and productively as a professional developer.
The Rails 7 Way
Obie Fernandez, Lucas Dohmen, and Tom Henrik AadlandThe Rails™ 7 Way is the comprehensive, authoritative reference guide for professionals delivering production-quality code using modern Ruby on Rails. It illuminates the entire Rails 7 API, its most powerful idioms, design approaches, and libraries. Building on the previous editions, this edition has been heavily refactored and updated.
Ansible for DevOps
Jeff GeerlingAnsible is a simple, but powerful, server and configuration management tool. Learn to use Ansible effectively, whether you manage one server—or thousands.
Top Bundles
- #1
Software Architecture
2 Books
"Software Architecture for Developers" is a practical and pragmatic guide to modern, lightweight software architecture, specifically aimed at developers. You'll learn:The essence of software architecture.Why the software architecture role should include coding, coaching and collaboration.The things that you really need to think about before... - #2
CCIE Service Provider Ultimate Study Bundle
2 Books
Piotr Jablonski, Lukasz Bromirski, and Nick Russo have joined forces to deliver the only CCIE Service Provider training resource you'll ever need. This bundle contains a detailed and challenging collection of workbook labs, plus an extensively detailed technical reference guide. All of us have earned the CCIE Service Provider certification... - #3
Modern C++ Collection
3 Books
Get All about Modern C++C++ Standard Library, including C++20Concurrency with Modern C++, including C++20C++20Each book has about 200 complete code examples. Updates are included. When I update one of the books, you immediately get the updated bundle. You can expect significant updates to each new C++ standard (C++23, C++26, .. ) and also... - #4
Pattern-Oriented Memory Forensics and Malware Detection
2 Books
This training bundle for security engineers and researchers, malware and memory forensics analysts includes two accelerated training courses for Windows memory dump analysis using WinDbg. It is also useful for technical support and escalation engineers who analyze memory dumps from complex software environments and need to check for possible... - #5
1500 QUIZ COMMENTATI (3 libri)
3 Books
Tre libri dei QUIZ MMG Commentati al prezzo di DUE! I QUIZ dei concorsi ufficiali di Medicina Generale relativi agli anni: 2000-2001-2003-2012-2013-2014-2015-2016-2017-2018-2019-2020-2021 +100 inediti Raccolti in unico bundle per aiutarvi nello studio e nella preparazione al concorso. All'interno di ogni libro i quiz sono stati suddivisi per... - #6
Practical FP in Scala + Functional event-driven architecture
2 Books
Practical FP in Scala (A hands-on approach) & Functional event-driven architecture, aka FEDA, (Powered by Scala 3), together as a bundle! The content of PFP in Scala is a requirement to understand FEDA so why not take advantage of this bundle!? - #8
Growing Agile: The Complete Coach's Guide
7 Books
Growing Agile: Coach's Guide Series This bundle provides a collection of training and workshop plans for a variety of agile topics. The series is aimed at agile coaches, trainers and ScrumMasters who often find themselves needing to help teams understand agile concepts. Each book in the series provides the plans, slides, handouts and activity... - #9
Development and Deployment of Multiplayer Online Games, Part ARCH. Architecture (Vol. I-III)
3 Books
What's the Big Idea? The idea behind this book is to summarize the body of knowledge that already exists on multiplayer games but is not available in one single place.And quite a fewof the issues discussed within this series (planned as three nine volumes ~300 pages each), while known in the industry, have not been published at all (except for...