Book Image

Reactive Programming in Kotlin

By : Rivu Chakraborty
Book Image

Reactive Programming in Kotlin

By: Rivu Chakraborty

Overview of this book

In today's app-driven era, when programs are asynchronous, and responsiveness is so vital, reactive programming can help you write code that's more reliable, easier to scale, and better-performing. Reactive programming is revolutionary. With this practical book, Kotlin developers will first learn how to view problems in the reactive way, and then build programs that leverage the best features of this exciting new programming paradigm. You will begin with the general concepts of Reactive programming and then gradually move on to working with asynchronous data streams. You will dive into advanced techniques such as manipulating time in data-flow, customizing operators and provider and how to use the concurrency model to control asynchronicity of code and process event handlers effectively. You will then be introduced to functional reactive programming and will learn to apply FRP in practical use cases in Kotlin. This book will also take you one step forward by introducing you to Spring 5 and Spring Boot 2 using Kotlin. By the end of the book, you will be able to build real-world applications with reactive user interfaces as well as you'll learn to implement reactive programming paradigms in Android.
Table of Contents (20 chapters)
Title Page
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Dedication
Preface

Spring – AOP


Before learning how to implement Aspect-oriented programming with Spring, we should first learn what Aspect-oriented programming is. The definition of Aspect-oriented programming says it is a programming paradigm that aims to increase modularity by allowing the separation of cross-cutting concerns. It does so by adding additional behavior to existing code (an advice) without modifying the code itself.

Now, what did we mean by cross-cutting concerns? Let's explore.

In a real-life project, multiple components play their own role. For example, if we take our previous scenario into account, the Student class itself is a component, similarly there could be a faculty component who would evaluate the student based on his/her performance. So, let's add a faculty to our program.

The Faculty class should be simple enough, with just a method to evaluate a student. Just as follows:

    class Faculty { 
      fun evaluateAssignment() { 
        val marks = Random().nextInt(10) 
        println...