This tutorial is about Kotlin Data classes, requirements that data class must fulfill, and their standard functionalities. Data Classes Data classes are classes whose main purpose is to hold data/state and contains standard functionalities. A data keyword is used to declare a class as a data class. Example: data class Student(val name: String, val age: Int) …
This tutorial is about object declarations (singletons) and object expressions with the help of examples. Object Declarations Object declarations defines singletons. Singleton is an object-oriented pattern where a class can have only one instance (object) at a time. Kotlin creates singletons with the object keyword. The object declaration can have functions, properties, and the init …
This tutorial is about companion objects in Kotlin with the help of examples. Kotlin doesn’t have a static keyword. Static members belong to a type, and not to an instance of a type. In kotlin to achieve this static feature, we make use of companion object. companion object An object declaration inside a class can be …
This tutorial is about how to use getters and setters in Kotlin with the help of simple example. Getters and Setters Getters are used for getting value of the property and Setters are used for setting the value of the property. Setters can have visibility modifiers but Getters always have the same visibility as the …
This post is about Access/Visibility modifiers in kotlin and how to use them. Access Modifiers In Kotlin, visibility modifiers are used to restrict the accessibility of Classes, objects, interfaces, constructors, functions, properties and their setters to a certain level. Getters always have the same visibility as the property. There are four visibility modifiers in Kotlin: public protected internal …
This article is about interfaces and how to implement it in Kotlin with the help of simple examples. Interfaces In Kotlin, Interfaces can contain declarations of abstract methods (have no body), as well as method implementation of non-abstract methods. Interfaces can have properties but these need to be abstract or to provide accessor implementations. Creating …
In this article, you will learn about Kotlin abstract classes, abstract methods and how to use them in our program with the help of examples. Abstract Classes An abstract class is a class that cannot be instantiated (we cannot create objects of an abstract class). Syntax We use the abstract keyword to declare an abstract class. abstract class className …
In this article, you will learn about Constructors (both primary and secondary constructor) behavior in Inheritance, in Kotlin with the help of examples. A constructor for a class is a special member function, which is called implicitly, just after the memory is allocated for the object to initialize the properties of the newly created object …
In this tutorial, we will learn about Inheritance in Kotlin with the help of examples. Inheritance Inheritance is one of the key feature of OOP (Object Oriented Programming). Inheritance can be defined as the process where one class is allowed to inherit the features (properties and functions) of another class. The class which inherits the features of other …
In this article, you will learn to extend a class with new functionality using extension functions. Extension Function Kotlin provides the ability to add methods to the existing classes without having to inherit from the class or use design patterns such as Decorator to do this. This is achieved using special declarations called extensions. Using …
