Kotlin In Action Second Edition

Expert guidance and amazing examples from core Kotlin’s developers! It’s everything you need to get up and running fast. In Kotlin in Action, Second Edition you will learn: Kotlin statements and functions, and classes and types Functional programming on the JVM The Kotlin standard library and out-of-the-box features Writing clean and idiomatic code Combining Kotlin and Java Improve code reliability with Null safety Domain-specific languages Kotlin concurrency Mastering the kotlinx.coroutines library Kotlin in Action, Second Edition is a complete guide to the Kotlin language written especially for readers familiar with Java or another OO language. In it, core Kotlin language developers share their unique insights, along with practical techniques and hands-on examples. You’ll quickly progress from language basics to building production-quality applications that take advantage of Kotlin’s unique features. This new second edition is fully updated to include the latest innovations, and it adds new chapters dedicated to coroutines and concurrency. Purchase of the print book includes a free eBook in PDF and ePub formats from Manning Publications. About the technology Coding with Kotlin means less hassle and more productivity. This JVM-based language offers an expressive syntax, a strong intuitive type system, and great tooling support—plus seamless interoperability with existing Java code, libraries, and frameworks. Kotlin is general purpose, safe, pragmatic, and the premier language of Android development. While the language has grown beyond its initial Java-centric focus, you can still use and integrate with your favorite Java tools and libraries, including Spring. About the book Kotlin in Action, Second Edition teaches you Kotlin techniques you can use for almost any type of application, from enterprise services to Android apps. The authors are all members of the Kotlin team, so you can trust that even the gnarly details are dead accurate. You’ll start with Kotlin fundamentals, learning how the language handles everything from statements and functions to classes and types, and about its unique features that make Kotlin programming so seamless. As you progress through this masterful book, you’ll get hands-on with the Kotlin standard library, functional programming in Kotlin, and advanced features such as generics and reflection. And this updated second edition now covers coroutines and structured concurrency to help you create efficient high-performance applications. About the author Roman Elizarov is a Project Lead for Kotlin at JetBrains and currently focuses on the Kotlin language design in the role of Lead Language Designer. Roman Elizarov previously designed and developed high-performance trading software for leading brokerage firms and market data delivery services that routinely handle millions of events per second. He has been working on Kotlin at JetBrains since 2016 and has contributed to the design of Kotlin coroutines and the development of the Kotlin coroutines library. Svetlana Isakova began as a member of the Kotlin compiler team and is now a developer advocate for JetBrains. She teaches Kotlin and speaks at conferences worldwide. She is a co-creator of the course "Kotlin for Java developers" at Coursera and is a co-author of the book "Atomic Kotlin." As a Kotlin Developer Advocate at JetBrains, Sebastian Aigner spends a lot of time thinking about how technologies can empower and delight people. When he first tried Kotlin, it was love at first sight.He gave talks at KotlinConf, participated in the Kotlin/Everywhere campaign, and spoke at a multitude of other conferences. He hosts the Talking Kotlin podcast together with Hadi Hariri, and creates videos for the official Kotlin YouTube channel. Dmitry Jemerov has been working with JetBrains since 2003. He was one of the initial developers working on Kotlin as the project was started, and he’s deeply familiar with the design of the language and the reasons for the decisions that were made during its development. He’s currently responsible for Kotlin documentation.

Summary Kotlin in Action guides experienced Java developers from the language basics of Kotlin all the way through building applications to run on the JVM and Android devices. Foreword by Andrey Breslav, Lead Designer of Kotlin. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Developers want to get work done - and the less hassle, the better. Coding with Kotlin means less hassle. The Kotlin programming language offers an expressive syntax, a strong intuitive type system, and great tooling support along with seamless interoperability with existing Java code, libraries, and frameworks. Kotlin can be compiled to Java bytecode, so you can use it everywhere Java is used, including Android. And with an effi cient compiler and a small standard library, Kotlin imposes virtually no runtime overhead. About the Book Kotlin in Action teaches you to use the Kotlin language for production-quality applications. Written for experienced Java developers, this example-rich book goes further than most language books, covering interesting topics like building DSLs with natural language syntax. The authors are core Kotlin developers, so you can trust that even the gnarly details are dead accurate. What's Inside Functional programming on the JVM Writing clean and idiomatic code Combining Kotlin and Java Domain-specific languages About the Reader This book is for experienced Java developers. About the Author Dmitry Jemerov and Svetlana Isakova are core Kotlin developers at JetBrains. Table of Contents PART 1 - INTRODUCING KOTLIN Kotlin: what and why Kotlin basics Defining and calling functions Classes, objects, and interfaces Programming with lambdas The Kotlin type system PART 2 - EMBRACING KOTLIN Operator overloading and other conventions Higher-order functions: lambdas as parameters and return values Generics Annotations and reflection DSL construction

Make the most of Kotlin by leveraging design patterns and best practices to build scalable and high performing apps Key Features Understand traditional GOF design patterns to apply generic solutions Shift from OOP to FP; covering reactive and concurrent patterns in a step-by-step manner Choose the best microservices architecture and MVC for your development environment Book Description Design patterns enable you as a developer to speed up the development process by providing you with proven development paradigms. Reusing design patterns helps prevent complex issues that can cause major problems, improves your code base, promotes code reuse, and makes an architecture more robust. The mission of this book is to ease the adoption of design patterns in Kotlin and provide good practices for programmers. The book begins by showing you the practical aspects of smarter coding in Kotlin, explaining the basic Kotlin syntax and the impact of design patterns. From there, the book provides an in-depth explanation of the classical design patterns of creational, structural, and behavioral families, before heading into functional programming. It then takes you through reactive and concurrent patterns, teaching you about using streams, threads, and coroutines to write better code along the way By the end of the book, you will be able to efficiently address common problems faced while developing applications and be comfortable working on scalable and maintainable projects of any size. What you will learn Get to grips with Kotlin principles, including its strengths and weaknesses Understand classical design patterns in Kotlin Explore functional programming using built-in features of Kotlin Solve real-world problems using reactive and concurrent design patterns Use threads and coroutines to simplify concurrent code flow Understand antipatterns to write clean Kotlin code, avoiding common pitfalls Learn about the design considerations necessary while choosing between architectures Who this book is for This book is for developers who would like to master design patterns with Kotlin to build efficient and scalable applications. Basic Java or Kotlin programming knowledge is assumed

What will you learn from this book? Head First Kotlin is a complete introduction to coding in Kotlin. This hands-on book helps you learn the Kotlin language with a unique method that goes beyond syntax and how-to manuals and teaches you how to think like a great Kotlin developer. You’ll learn everything from language fundamentals to collections, generics, lambdas, and higher-order functions. Along the way, you’ll get to play with both object-oriented and functional programming. If you want to really understand Kotlin, this is the book for you. Why does this book look so different? Based on the latest research in cognitive science and learning theory, Head First Kotlin uses a visually rich format to engage your mind rather than a text-heavy approach that puts you to sleep. Why waste your time struggling with new concepts? This multisensory learning experience is designed for the way your brain really works.

Delve into the world of Kotlin and learn to build powerful Android and web applications Key FeaturesLearn the fundamentals of Kotlin to write high-quality codeTest and debug your applications with the different unit testing frameworks in KotlinExplore Kotlin's interesting features such as null safety, reflection, and annotationsBook Description Kotlin is a general-purpose programming language used for developing cross-platform applications. Complete with a comprehensive introduction and projects covering the full set of Kotlin programming features, this book will take you through the fundamentals of Kotlin and get you up to speed in no time. Learn Kotlin Programming covers the installation, tools, and how to write basic programs in Kotlin. You'll learn how to implement object-oriented programming in Kotlin and easily reuse your program or parts of it. The book explains DSL construction, serialization, null safety aspects, and type parameterization to help you build robust apps. You'll learn how to destructure expressions and write your own. You'll then get to grips with building scalable apps by exploring advanced topics such as testing, concurrency, microservices, coroutines, and Kotlin DSL builders. Furthermore, you'll be introduced to the kotlinx.serialization framework, which is used to persist objects in JSON, Protobuf, and other formats. By the end of this book, you'll be well versed with all the new features in Kotlin and will be able to build robust applications skillfully. What you will learnExplore the latest Kotlin features in order to write structured and readable object-oriented codeGet to grips with using lambdas and higher-order functionsWrite unit tests and integrate Kotlin with Java codeCreate real-world apps in Kotlin in the microservices styleUse Kotlin extensions with the Java collections libraryUncover destructuring expressions and find out how to write your ownUnderstand how Java-nullable code can be integrated with Kotlin featuresWho this book is for If you’re a beginner or intermediate programmer who wants to learn Kotlin to build applications, this book is for you. You’ll also find this book useful if you’re a Java developer interested in switching to Kotlin.

Kotlin is a statically typed programming language designed to interoperate with Java and fully supported by Google on the Android operating system. It is also a multiplatform language that can be used to write code that can be shared across platforms including macOS, iOS, Windows, and JavaScript. Based on Big Nerd Ranch’s popular Kotlin Essentials course, this guide shows you how to work effectively with Kotlin through hands-on examples and clear explanations of key Kotlin concepts and foundational APIs. Written for Kotlin 1.5, this book will also introduce you to JetBrains’ IntelliJ IDEA development environment. Whether you are an experienced developer or are learning your first programming language – and whether you are interested in Kotlin for Android, server-side, or multiplatform projects – the authors will guide you from first principles to advanced Kotlin usage. By the end of this book, you will be empowered to create reliable, concise applications in Kotlin.

Use Kotlin to build Android apps, web applications, and more—while you learn the nuances of this popular language. With this unique cookbook, developers will learn how to apply thisJava-based language to their own projects. Both experienced programmers and those new to Kotlin will benefit from the practical recipes in this book. Author Ken Kousen (Modern Java Recipes) shows you how to solve problems with Kotlin by concentrating on your own use cases rather than on basic syntax. You provide the contextand this book supplies the answers. Already big in Android development, Kotlin can be used anywhere Java is applied, as well as for iOS development, native applications, JavaScriptgeneration, and more. Jump in and build meaningful projects with Kotlin today. Apply functional programming concepts, including lambdas, sequences, and concurrency See how to use delegates, late initialization, and scope functions Explore Java interoperability and access Java libraries using Kotlin Add your own extension functions Use helpful libraries such as JUnit 5 Get practical advice for working with specific frameworks, like Android and Spring

Master the concise and expressive power of a pragmatic multi-paradigm language for JVM, Android and beyond DESCRIPTIONÊ The purpose of this book is to guide a reader through the capabilities of the Kotlin language and give examples of using it for development of various applications be it desktop, mobile or Web. Although our primary focus is on the JVM and Android, the knowledge weÕre sharing here to various extents applies to other Kotlin-supported platforms such as JavaScript, native and even multi-platform applications. The book starts with an introduction to language and its ecosystem that will give you an understanding of the key ideas behind Kotlin design, introduce you to the Kotlin tooling and present you the basic language syntax and constructs. In the next chapters weÕll get to know the multi-paradigm nature of Kotlin which allows you to create powerful abstractions by combining various aspects of functional and object-oriented programming. WeÕll talk about using common Kotlin APIs such as the standard library, reflection, and coroutine-based concurrency as well as the means for creating your own flexible APIs based on domain-specific languages. In the concluding chapters, weÕll give examples of using Kotlin for more specialized tasks such as testing, building Android applications, Web development and creating microservices. KEY FEATURESÊÊ - Language fundamentals - Object-oriented and functional programming with Kotlin - Kotlin standard library - Building domain-specific languages - Using Kotlin for Web development - Kotlin for Android platform - Coroutine-based concurrency WHAT WILL YOU LEARNÊ By the end of the book, youÕll obtain a thorough knowledge of all basic aspects of Kotlin programming. YouÕll be able to create a flexible and reusable code by taking advantage of object-oriented and functional features, use Kotlin standard library, compose your own domain-specific languages, write asynchronous code using Kotlin coroutines library as well. YouÕll also have a basic understanding of using Kotlin for writing test code, web applications and Android development. This knowledge will also give you a solid foundation for deeper learning of related development platforms, tools and frameworks. WHO THIS BOOK IS FORÊ The book is primarily aimed at developers familiar with Java and JVM and willing to get a firm understanding of Kotlin while having little to no experience in that language. Discussion of various language features will be accompanied, if deemed necessary, by comparisons with their JavaÕs analogs which should simplify Java-to-Kotlin transition. Most of the material, however, is rather Java-agnostic and should be beneficial even without prior Java knowledge. In general, experience in object-oriented or functional paradigm is a plus, but not required. Table of Contents 10. Annotations and Reflection 11. Domain-Specific Languages 12.Ê Java Interoperability 13. Concurrency 14.Ê Testing with Kotlin 15.Ê Android Applications 16.Ê Web Development with Ktor 17.Ê Building Microservices