Book Image

Learn Kotlin Programming - Second Edition

By : Stephen Samuel, Stefan Bocutiu
Book Image

Learn Kotlin Programming - Second Edition

By: Stephen Samuel, Stefan Bocutiu

Overview of this book

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.
Table of Contents (21 chapters)
Free Chapter
1
Section 1: Fundamental Concepts in Kotlin
5
Section 2: Practical Concepts in Kotlin
15
Section 3: Advanced Concepts in Kotlin

Channels

Channels are the coroutine dual of concurrent blocking queues. A blocking queue is a data type that provides operations so that you can add or remove elements from an internal buffer. These operations will block when they cannot be completed.

Typically, these operations are called put, which adds elements to the buffer—and blocks when the queue is full (unblocks when space is freed by a consumer removing an element)—and take, which removes elements from the queue—and blocks when the queue is empty (unblocks when the queue is populated by a producer adding an element).

Channels offer the same basic functionality but rather than using blocking operations, they use suspendable functions, which allows producer-consumer style patterns but with the efficiency of coroutines. In Kotlin, the add and remove functions of a channel are called send and receive...