Kotlin Basics

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

Familiarize yourself with all of Kotlin's features with this in-depth guide About This Book Get a thorough introduction to Kotlin Learn to use Java code alongside Kotlin without any hiccups Get a complete overview of null safety, Generics, and many more interesting features Who This Book Is For The book is for existing Java developers who want to learn more about an alternative JVM language. If you want to see what Kotlin has to offer, this book is ideal for you. What You Will Learn Use new features to write structured and readable object-oriented code Find out how to use lambdas and higher order functions to write clean, reusable, and simple code Write unit tests and integrate Kotlin tests with Java code in a transitioning code base Write real-world production code in Kotlin in the style of microservices Leverage Kotlin's extensions to the Java collections library Use destructuring expressions and find out how to write your own Write code that avoids null pointer errors and see how Java-nullable code can integrate with features in a Kotlin codebase Discover how to write functions in Kotlin, see the new features available, and extend existing libraries Learn to write an algebraic data types and figure out when they should be used In Detail Kotlin has been making waves ever since it was open sourced by JetBrains in 2011; it has been praised by developers across the world and is already being adopted by companies. This book provides a detailed introduction to Kotlin that shows you all its features and will enable you to write Kotlin code to production. We start with the basics: get you familiar with running Kotlin code, setting up, tools, and instructions that you can use to write basic programs. Next, we cover object oriented code: functions, lambdas, and properties – all while using Kotlin's new features. Then, we move on to null safety aspects and type parameterization. We show you how to destructure expressions and even write your own. We also take you through important topics like testing, concurrency, microservices, and a whole lot more. By the end of this book you will be able to compose different services and build your own applications. Style and approach An easy to follow guide that covers the full set of features in Kotlin programming.

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.

Enhance your Kotlin programming skills by building 3 real-world applications Key Features Build three full-fledged, engaging applications from scratch and learn to deploy them Enhance your app development and programming activities with Kotlin’s powerful and intuitive tools and utilities. Experience the gentle learning curve, expressiveness, and intuitiveness of Kotlin, as you develop your own applications Book Description Kotlin greatly reduces the verbosity of source code. With Google having announced their support for Kotlin as a first-class language for writing Android apps, now's the time learn how to create apps from scratch with Kotlin Kotlin Programming By Example takes you through the building blocks of Kotlin, such as functions and classes. You’ll explore various features of Kotlin by building three applications of varying complexity. For a quick start to Android development, we look at building a classic game, Tetris, and elaborate on object-oriented programming in Kotlin. Our next application will be a messenger app, a level up in terms of complexity. Before moving onto the third app, we take a look at data persistent methods, helping us learn about the storage and retrieval of useful applications. Our final app is a place reviewer: a web application that will make use of the Google Maps API and Place Picker. By the end of this book, you will have gained experience of of creating and deploying Android applications using Kotlin. What you will learn Learn the building blocks of the Kotlin programming language Develop powerful RESTful microservices for Android applications Create reactive Android applications efficiently Implement an MVC architecture pattern and dependency management using Kotlin Centralize, transform, and stash data with Logstash Secure applications using Spring Security Deploy Kotlin microservices to AWS and Android applications to the Play Store Who this book is for This book is for those who are new to Kotlin or are familiar with the basics, having dabbled with Java until now. Basic programming knowledge is mandatory.

Build Android apps using the popular and efficient Android Studio 3 suite of tools, an integrated development environment (IDE) with which Android developers can now use the Kotlin programming language. With this book, you’ll learn the latest and most productive tools in the Android tools ecosystem, ensuring quick Android app development and minimal effort on your part. Along the way, you’ll use Android Studio to develop apps tier by tier through practical examples. These examples cover core Android topics such as Activities, Intents, BroadcastReceivers, Services and AsyncTask. Then, you’ll learn how to publish your apps and sell them online and in the Google Play store. What You’ll LearnUse Android Studio 3 to quickly and confidently build your first Android apps Build an Android user interface using activities and layouts, event handling, images, menus and the action bar Incorporate new elements including fragments Learn how data is persisted Use Kotlin to build apps Who This Book Is For Those who may be new to Android Studio 3 or Android Studio in general. You may or may not be new to Android development in general. Some prior experience with Java is also recommended.

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.

Crafting the Future of Android and Beyond Embark on an enlightening exploration of Kotlin—the modern, concise, and expressive language that's redefining Android development and expanding its influence across various platforms. Whether you're just beginning your programming saga or are a veteran developer looking to update your toolkit, "Mastering Kotlin" offers the guidance and insights you need. Dive in and uncover: · Kotlin Foundations: Traverse the essentials of Kotlin, from its basic syntax to its functional and object-oriented programming paradigms. · Elevated Code: Grasp the nuances of idiomatic Kotlin, ensuring your code is both powerful and elegant. · Expert Techniques: Delve into advanced topics like coroutines, DSL creation, and multiplatform development, empowering you to harness Kotlin's full potential. · Practical Endeavors: Engage with hands-on projects that provide real-world context, ensuring your skills are battle-tested and industry-ready. · Interoperability Insights: Seamlessly integrate Kotlin with existing Java codebases and understand the harmony between these two juggernauts of the JVM. "Mastering Kotlin" is more than a guide—it's a compass, guiding you through the ever-evolving landscape of modern development with clarity and precision. Step into the future of development with Kotlin at your fingertips.

Get started with Kotlin programming for building real world applications Key Features Start programming with Kotlin Explore Kotlin language syntax, standard libraries and Java Interoperability Builds an example application with what you learn Book Description Kotlin is a general purpose, object-oriented language that primarily targets the JVM and Android. Intended as a better alternative to Java, its main goals are high interoperability with Java and increased developer productivity. Kotlin is still a new language and this book will help you to learn the core Kotlin features and get you ready for developing applications with Kotlin. This book covers Kotlin features in detail and explains them with practical code examples.You will learn how to set up the environment and take your frst steps with Kotlin and its syntax. We will cover the basics of the language, including functions, variables, and basic data types. With the basics covered, the next chapters show how functions are first-class citizens in Kotlin and deal with the object-oriented side of Kotlin. You will move on to more advanced features of Kotlin. You will explore Kotlin's Standard Library and learn how to work with the Collections API. The book finishes by putting Kotlin in to practice, showing how to build a desktop app. By the end of this book, you will be confident enough to use Kotlin for your next project. What you will learn Programming in Kotlin language syntax, basic types, control ?ow, classes, and OOP Writing functions and functional programming in Kotlin Defning and importing from packages in Kotlin Running Kotlin on JVMs and Android runtimes Working with the Kotlin Standard Library and advanced features of Kotlin programming Setting up a Kotlin development environment with JetBrains tools Building real-world applications with Kotlin Who this book is for This book is intended for anybody who wants to learn the most important Kotlin features. No experience of Kotlin is expected.