Kotlin is an expressive, concise, and statically typed, general-purpose programming language developed by JetBrains that reduces common code errors and is easily integrable into existing apps.
Kotlin is compatible with all Java frameworks and libraries, and it's designed to integrate smoothly with Marven and Gradle build systems.
At Google I/O 2017, Kotlin was introduced as the official language for developing android apps. Also, at Google I/O 2019, it was announced that Android development would be increasingly Kotlin-first. Today, nearly 60% of the top 1,000 Android apps contain Kotlin code.
Similarities in typing and syntax make Kotlin very easy to master for anyone already working with Java. Kotlin has Android Studio support; you can download the Kotlin plugin in Android Studio and convert the entire Java code into a Kotlin code. Plus, many apps are already built with Kotlin.
Features of Kotlin:
Kotlin provides many new libraries and syntactic sugar to reduce boilerplate, which helps increase development speed. That said, be cautious and methodical when using Kotlin's standard library functions, such as collection functions, coroutines, and lambdas.
One of Kotlin's key benefits is the support for multiplatform programming, which reduces time spent writing and maintaining the same code for different platforms.
Kotlin for server-side
Kotlin is an excellent ally when developing server-side applications because Kotlin applications can be deployed into any host that supports Java Web applications, including Amazon Web Services, Google Cloud Platform, and more.
Type Inference
With Kotlin, you don't need to specify the data type of each variable. But if you want to define explicitly:
val number = 10
// explicitly defined
val number: Int = 10
Less code
It reduces the amount of boilerplate code. Any chunk of code written in Kotlin is much smaller than that written in Java, as it is less verbose. Just see the below example in "Data Class."
Safer code
Kotlin has many language features that will help you avoid common programming mistakes, such as null pointer exceptions. According to the Google Developers Website, "Android apps that contain Kotlin code are 20% less likely to crash."
To assign a null value to any string, it should be declared as nullable.
String nullStr? = null
NullPointerException or NPE is one of Java's main drawbacks, and the only possible reason for NPE is an explicit call to throw NullPointerException.
Data Classes
Data classes lead to boilerplate auto-generation like equals, hashCode, getters/setters, and much more.
/* Java Code */
class Book {
private String title;
private Author author;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public Author getAuthor() {
return author;
}
public void setAuthor(Author author) {
this.author = author;
}
}
But in Kotlin, the same above class can define concisely in one line -
/* Kotlin Code */
data class Book(var title:String, var author:Author)
Interoperable
If you call Java-based code from Kotlin or vice versa, Kotlin is 100% interoperable with the Java programming language.
Structured Concurrency
Kotlin Coroutines make asynchronous code as easy to work with as blocking code. Coroutines dramatically simplify background task management for everything from network calls to accessing local data.
What does Kotlin-first mean?
Kotlin supports many tools and content. Google is continuing to provide support for using APIs from the Java programming language.
A success story from Google Developers is that of the Google Home team, where migrating new feature development to Kotlin resulted in a 33% reduction in codebase size and a 30% reduction in the number of NPE crashes.
Conclusion
If you are already a Java developer, learning and starting development with Kotlin's new features (the language of the future) would be a great idea. Finally, it is all about choosing the language you are comfortable with and the one that will best fit your project's work!
Resources:
Sites: https://kotlinlang.org - The JetBrains site for all things Kotlin.
Tutorials: https://play.kotlinlang.org/byExample/01_introduction/01_Hello%20world - An interactive tutorial by JetBrains that illustrates Kotlin features and syntax.