Master Kotlin

Welcome to another vast and interesting programming language Kotlin

What is Kotlin? : Kotlin is a  strong statically typed ( Wherein the type of variable is load at compiled time) programming language for modern multiplatform applications, it was introduced by JetBrains. It was announced by google an official language for android development in 2017.

It is 100% interoperable with Java and Android, One can easily convert java codes to Kotlin using popular IDE's like Netbeans and Android Studio.

Using Kotlin we can build android applications, browsers as well as building server-side applications.

Here we will be focusing on developing android apps using Kotlin.

Prerequisites:

Once you move forward it recommended that one should have the basic knowledge of  Java programming language., Although it is assumed that the readers are having a reasonable exposure to the programming environment and knowledge of basic concepts such as variables, commands, syntax, etc. We strongly recommend that you gain some basic knowledge of Java programming language before proceeding with Kotlin programming.

To start with kotlin the user should download and Install JDK- The link of the same is given below.
Installation of JDK 8 is recommended as it contains the file which can be downloaded for
32 /64 bit OS.
The video tutorial is for downloading the perquisites is given below, from where you can go to the link and the process of installation of perquisites.

JDK Installation: 

  

Kotlin and Visual Studio Code: 

Kotlin and Intelli JDE:
 

Fundamentals of Kotlin:

The basic data types available in kotlin language is

Numbers

Kotlin provides a set of built-in types that represent numbers.
For integer numbers, there are four types with different sizes and, hence, value ranges.

Type	Size
Long	64
Int	32
Short	16
Byte	8

For floating-point numbers, Kotlin provides types

Type	Size
Float	32
Double	64

Characters

Kotlin represents character using char. Character should be declared in a single quote like ‘K’. When you enter the below-mentioned codes, look how Kotlin interprets the character variable. Kotlin variable can be declared in two ways - one using “var” and another using “val”.

Boolean

Boolean is as simple like other programming languages. We have only two values for Boolean – either true or false.

Arrays

Arrays are a collection of homogeneous data. Like Java, Kotlin supports arrays of different data types. The indexing of the array is similar to other programming languages.

Strings

Strings are character arrays. Like Java, they are immutable in nature. We have two kinds of string available in Kotlin - one is called raw String and another is called escaped String.

Collections

Collection is one of the very important parts of the data structure, Which makes software development easy for engineers. Kotlin has two types of collection - one is immutable collection (which means lists, maps, and sets that cannot be editable) and another is a mutable collection (this type of collection is editable). In collection, Kotlin provides some useful methods such as first(), last(), filter(), etc. All these methods are self-descriptive and easy to implement. Moreover, Kotlin follows the same structure such as Java while implementing collection. You are free to implement any collection of your choices such as Map and Set.

Ranges

Ranges is another unique characteristic of Kotlin, It provides an operator that helps you iterate through a range. Internally, it is implemented using rangeTo() and its operator form is (..).

Control Flow of Kotlin

If - Else

Kotlin is a functional language, so like every other functional language in Kotlin “if” is an expression. The expression “if” will return a value whenever necessary, and “if-else”  is used as an initial conditional operator.

Use of When

A conditional operator when multiple conditions can be applied on a particular variable, “when” operator matches the variable value against multiple conditions.

For Loop

Like other programming languages, Kotiln also provides looping methodology, and among them “For” is the most successful one.

While Loop and Do-While Loop

While and Do-While works in the same way as in other programming languages. The only difference, in case of Do-while loop, is that the condition is tested at the end of the loop.

Use of Return, Break, Continue

Return is a keyword that returns some value to the calling function from the called function. Continue and break is one of the important parts of a logical problem. The “break” keyword terminates the controller flow if some condition has failed and “continue” does the opposite of a break.

Kotlin - Class & Object

 Kotlin allows a developer to create several objects of a class and the user is free to include its class members and functions, in the same way as Java.

Nested Class

When a class has been created inside another class, then it is called as a nested class.

Inner Class

When a nested class is marked as an “inner”, then it will be called as an Inner class. An inner class can be accessed by the data member of the outer class.

Anonymous Inner Class

Anonymous inner class is one of the concepts which makes the life of a programmer very easy. The concept of an anonymous inner block comes into the picture when the user is implementing an interface.

Type Aliases

Type aliases is a property of Kotlin compiler which provides the flexibility of creating a new name of an existing type, it does not create a new type. If the type name is too long, you can easily introduce a shorter name and use the same for future usage.

Kotlin – Constructors

Kotlin has two types of constructor - one is the primary constructor and the other is the secondary constructor. The primary constructor initializes the class, whereas the secondary constructor helps to include some extra logic while initializing the same. The primary constructor can be declared at class header

Kotlin – Inheritance

We all know that inheritance means accruing some properties of the mother class into the child's class. In Kotlin we need to use the keyword “open” in front of the class declaration to make it allowable to inherit.

Kotlin – Interface

In Kotlin, the interface works exactly similar to Java 8, which means they can contain method implementation as well as abstract methods declaration. An interface can be implemented by a class in order to use its defined functionality.

Kotlin doesn’t support multiple inheritances; however, the same thing can be done by implementing more than two interfaces at a time.

Kotlin - Visibility Control

There are four access modifiers available in Kotlin, like other OOP programming language; this modifier is applicable at multiple places such as in the class header or method declaration. Access modifier is used to restrict the usage of the variables, methods, and class used in the application.

Private

The classes, methods, and packages can be declared with a private modifier. Once anything is declared as private, then it will be accessible within its immediate scope

Protected

Protected is another access modifier for Kotlin, which is currently not available for a top-level declaration like any package cannot be protected. A protected class or interface is visible to its subclass only.

Internal

If anything is marked as internal, then that specific field will be in the internal field. An Internal package is visible only inside the module under which it is implemented. An internal class interface is visible only by other classes present inside the same package or the module.

Public

If no access modifier is specified, then by default it will be in the public scope and the same as accessible from anywhere in the project workspace.

Advantages and Disadvantages

Following are some of the advantages of using Kotlin for your application development.

Easy Language − Kotlin is a functional language and very easy to learn. The syntax is pretty much similar to Java, hence it is very easy to remember.

Runtime and Performance − Better performance and small runtime.

Interoperability − Kotlin is mature enough to build an interoperable application in a less complex manner.

Brand New − Kotlin is a brand new language that gives developers a fresh start. It is not a replacement of Java, though it is developed over JVM. It is accepted as the first official language of android development. Kotlin can be defined as - Kotlin = JAVA + extra updated new features.

Following are some of the disadvantages of Kotlin.

Namespace declaration − Kotlin allows developers to declare the functions at the top level. However, whenever the same function is declared in many places of your application, then it is hard to understand which function is being called.

No Static Declaration − Kotlin does not have usual static handling modifier like Java, which can cause some problems to the conventional Java developers.

I hope I covered most of  the basic  details of kotlin, want to learn more please visit 

our website http://skillbakery.com/courses/master-kotlin.html