Book Image

Kotlin Standard Library Cookbook

By : Samuel Urbanowicz
Book Image

Kotlin Standard Library Cookbook

By: Samuel Urbanowicz

Overview of this book

For developers who prefer a more simplistic approach to coding, Kotlin has emerged as a valuable solution for effective software development. The Kotlin standard library provides vital tools that make day-to-day Kotlin programming easier. This library features core attributes of the language, such as algorithmic problems, design patterns, data processing, and working with files and data streams. With a recipe-based approach, this book features coding solutions that you can readily execute. Through the book, you’ll encounter a variety of interesting topics related to data processing, I/O operations, and collections transformation. You’ll get started by exploring the most effective design patterns in Kotlin and understand how coroutines add new features to JavaScript. As you progress, you'll learn how to implement clean, reusable functions and scalable interfaces containing default implementations. Toward the concluding chapters, you’ll discover recipes on functional programming concepts, such as lambdas, monads, functors, and Kotlin scoping functions, which will help you tackle a range of real-life coding problems. By the end of this book, you'll be equipped with the expertise you need to address a range of challenges that Kotlin developers face by implementing easy-to-follow solutions.
Table of Contents (11 chapters)

Smart types checking with generic reified parameters

While implementing functions that support generic type arguments, we often deal with the need to provide additional information about object types at runtime. On the JVM platform, types have their representations in the Class<T> class instances. For example, we can face such a need while parsing JSON formatted data to the Kotlin class instances using the Gson library:

data class ApiResponse(val gifsWithPandas: List<ByteArray>)
data class Error(val message: String)

fun parseJsonResponse(json: String): ApiResponse {
Gson().fromJson(json, ApiResponse::class.java)
}

Normally, we can't access the generic type argument at runtime because of a JVM types erasure. However, Kotlin allows you to overcome this limitation because it preserves the type argument at runtime. In this recipe, we are going to tune up Gson&apos...