Book Image

Learning Scala Programming

By : Vikash Sharma
Book Image

Learning Scala Programming

By: Vikash Sharma

Overview of this book

Scala is a general-purpose programming language that supports both functional and object-oriented programming paradigms. Due to its concise design and versatility, Scala's applications have been extended to a wide variety of fields such as data science and cluster computing. You will learn to write highly scalable, concurrent, and testable programs to meet everyday software requirements. We will begin by understanding the language basics, syntax, core data types, literals, variables, and more. From here you will be introduced to data structures with Scala and you will learn to work with higher-order functions. Scala's powerful collections framework will help you get the best out of immutable data structures and utilize them effectively. You will then be introduced to concepts such as pattern matching, case classes, and functional programming features. From here, you will learn to work with Scala's object-oriented features. Going forward, you will learn about asynchronous and reactive programming with Scala, where you will be introduced to the Akka framework. Finally, you will learn the interoperability of Scala and Java. After reading this book, you'll be well versed with this language and its features, and you will be able to write scalable, concurrent, and reactive programs in Scala.
Table of Contents (21 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Objects as singletons


There are no static members or classes in Scala. Once you feel the need to create a static member, for example a static method or a class that is going to have only one instance, you should create an object. Yes, up until now, almost all the time we have been creating an object that extends the App trait so that we don't have to define the main method. This is the entry point to our application. So, it's also obvious that when we mention object, we don't mean an instance of any class; rather, an object in Scala has a different meaning.

An object, just like classes, is a container for functions and values. The reason why we may want to declare an object is so we can define utility methods for any particular type, or sometimes define JSON formatters and similar use cases. Let's take another look at how we can define an object:

object CountryUtil { 
   
} 

Looks like we just created an object. Nothing fancy, just an object keyword along with the name of the object. We know...