Kotlin: A multi-paradigm programming language from Google

Native Code and preferred language for Android App Developers

In this article, I have explained about Kotlin programming language, especially used in android app development as well as the essential information and important features of Kotlin.

Kotlin is a general-purpose, cross-platform and statically typed programming language with type interface. Kotlin is designed to interoperate fully with Java, and the JVM (Java Virtual Machine) version of its standard library depends on the Java Class Library, but type inference allows its syntax to be more concise. Kotlin mainly targets the JVM but also compiles to JavaScript or native code. Language development costs are borne by JetBrains, while the Kotlin Foundation protects the Kotlin trademark.

On 7 May 2019, Google announced that the Kotlin programming language is now its preferred language for Android app developers. Since the release of Android Studio 3.0 in October 2017, Kotlin has been included as an alternative to the standard Java compiler. The Android Kotlin compiler targets Java 6 by default but lets the programmer choose between Java 8 to 13, for optimization.

Brief History:-

In July 2011, JetBrains unveiled Project Kotlin, a new language for the JVM, which had been under development for a year. JetBrains lead Dmitry Jemerov said that most languages did not have the features they were looking for, with the exception of Scala. However, he cited the slow compilation time of Scala as a deficiency. One of the stated goals of Kotlin is to compile as quickly as Java. In February 2012, JetBrains open-sourced the project under the Apache 2 license.

The name comes from Kotlin Island, near St. Petersburg. Andrey Breslav mentioned that the team decided to name it after an island just like the name of Java.

• Kotlin v1.0:- Released on 15 February 2016. This is considered to be the first officially stable release.
• At Google, I/O 2017:- Google announced first-class support for Kotlin on Android.
• Kotlin v1.2:- Released on 28 November 2017. Sharing code between JVM and JavaScript platforms feature was newly added to this release. The full-stack demo has been made with the new Kotlin/JS Gradle Plugin.
• Kotlin v1.3:- Released on 29 October 2018 Bringing co-routines for asynchronous programming.
• Kotlin current version is v1.3. 61:- CoroutineDispatcher. isDispatchNeeded is promoted to stable API

Most Important Features of Kotlin:-

1. Open-source

First and foremost, Kotlin in an open-source programming language. This statically typed language was built by Jetbrains, who are also makers of IntelliJ IDE.

2. Java Interoperability

One of the best features of Kotlin programming language is its deep interoperability with Java, which is bound to attract more Java developers to learn Kotlin. It runs on the JVM and uses Java libraries and tools. It offers backward compatibility for Java versions 6 and 7.

3. Compiles to JVM bytecode or JS

As Kotlin compiles to JVM bytecode or JavaScript, Java and JS developers will be most tempted to learn this programming language.

4. Data Classes

A typical data class in Java has tons of boilerplate code one needs to skip while finding out the real use of that class. However, in Kotlin, you can write the equivalent of the same Java code in a very simple manner and save tons of typing and mental effort. It’s one of the best features of Kotin programming language.

5. Defaulted parameters

The defaulted parameters in Kotlin are pretty handy when you pass the arguments by name, instead of index. Their advantage is seen when there’s a function with tons of optional parameters.

6. No runtime overhead

The standard Kotlin library doesn’t have garbage, it’s tight and small. It has mostly focused extensions to the Java standard library. Many of its functions are inline-only that just become inline code. Kotlin has many optimizations which, specifically, help Android development.

7. Null Safety in Kotlin

Kotlin programming language’s type system aims at eliminating the perils of null references from code, which is often called The Billion Dollar Mistake. For example, in Java, accessing a member of null reference results in a null reference exception. Kotlin doesn’t compile code that assigns or returns null. This is seen as one of the most important features of Kotlin.

8. Extension functions

With extension functions in Kotlin, you can add methods to classes without making changes to their source code. Similar to Scala’s implicit methods, you can add methods on a per-user basis to classes. While extension functions are often controversial, every now and then it’s very useful.

9. Efficiency

The Kotlin programming language is not only easy to learn, it is also effective in the way that it codes your application. Developers won’t need to spend a lot of time grasping this language. The syntax is intuitive and lean.

10. Less code

Unlike Java, which needs you to write everything, Kotlin compiler can understand from the code and write the remaining code, for example, it can infer types in variable declarations. This increases productivity and saves time.

Summing Up Kotlin Features

Kotlin is a highly reliable, flexible, and safe language. With the minimal cost involved and increased efficiency promised by the language, using Kotlin could boost profitability and improve business. Furthermore, it will not just reduce errors but also crashes at runtime, thus making debugging reliable.

Applications:-

1. Server Side

Kotlin is a great fit for developing server-side applications, allowing you to write concise and expressive code while maintaining full compatibility with existing Java-based technology stacks and a smooth learning curve.

2. Android

You can use Kotlin along with the Java programming language in your applications without needing to migrate all your code to Kotlin.

3. JavaScript

When you choose the JavaScript target, any Kotlin code that is part of the project as well as the standard library that ships with Kotlin are transpile to JavaScript. However, this excludes the JDK and any JVM or Java framework or library used. Any file that is not Kotlin will be ignored during compilation.

4. Native

Kotlin/Native is a technology for compiling Kotlin code to native binaries, which can run without a virtual machine. It is an LLVM based backend for the Kotlin compiler and native implementation of the Kotlin standard library.

5. Data Science

From building data pipelines to productionizing machine learning models, Kotlin can be a great choice for working with data.

6. Multiplatform

Working on all platforms is an explicit goal for Kotlin, but we see it as a premise to a much more important goal: sharing code between platforms. With support for JVM, Android, JavaScript, iOS, Linux, Windows, Mac and even embedded systems like STM32, Kotlin can handle any and all components of a modern application.