Scala is a language that join both worlds “Functional Programming” and “Object Oriented”.
We talked a little bit about “Functional Programming” in the previous SKBs and today we are going to introduce the basics for “Object Oriented” : the classes and more specifically how to create an instance of a class.
We will be diving a bit more into the theory after the exercise.
A class is a collection of functions that can be reused. This collection is created with parameters and that will make the instance of the class behave differently.
In a lot of programming books, you will see a class being described as a “blueprint”. And using this “blueprint”, you are able to “instantiate”, or build, an object.
The way to build a class in Scala is using the keyword new.
To summarize all the terminology:
- Class: A collection of methods, values. Built with parameter(s). Instantiated to an object via the keyword
new. - Object: An instance of a class built with specific parameters.
- Instantiate: The action of creating an object from a class.
new: The keyword used in Scala to instantiate a class and make an object.- Field: The
valcontained in theclass. - Method: The
def(functions) contained in theclass. - Member: A term to describe both
fieldandmethod.