Book Image

Learning Concurrency in Kotlin

By : Miguel Angel Castiblanco Torres
Book Image

Learning Concurrency in Kotlin

By: Miguel Angel Castiblanco Torres

Overview of this book

Kotlin is a modern and statically typed programming language with support for concurrency. Complete with detailed explanations of essential concepts, practical examples and self-assessment questions, Learning Concurrency in Kotlin addresses the unique challenges in design and implementation of concurrent code. This practical guide will help you to build distributed and scalable applications using Kotlin. Beginning with an introduction to Kotlin's coroutines, you’ll learn how to write concurrent code and understand the fundamental concepts needed to write multithreaded software in Kotlin. You'll explore how to communicate between and synchronize your threads and coroutines to write collaborative asynchronous applications. You'll also learn how to handle errors and exceptions, as well as how to work with a multicore processor to run several programs in parallel. In addition to this, you’ll delve into how coroutines work with each other. Finally, you’ll be able to build an Android application such as an RSS reader by putting your knowledge into practice. By the end of this book, you’ll have learned techniques and skills to write optimized code and multithread applications.
Table of Contents (11 chapters)

RSS – Reading from multiple feeds concurrently

Now that we have a better understanding of the life cycle of a job, it's a good moment to go back to our Android RSS reader and improve it.

Supporting a list of feeds

Let's go back to our Android Studio project and create an immutable list to hold the feeds that we will fetch. For now, three feeds will be enough:

class MainActivity : AppCompatActivity() {

val feeds = listOf(
"https://www.npr.org/rss/rss.php?id=1001",
"http://rss.cnn.com/rss/cnn_topstories.rss",
"http://feeds.foxnews.com/foxnews/politics?format=xml"
)
...
}

Now we have a list of feeds that contain the URLs of NPR, CNN, and Fox News...