Biggest draws of Kotlin

8 key Kotlin features that give it an edge over Java

Juned Ghanchi
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Looking to replace Java with another language? The hype for Kotlin is on a steady incline, due to many of its features tackling Java shortcomings. In this article, you will find out about some of the key Kotlin features that may have you switching your main programming language. For instance, how is the power of Kotlin’s immutability harnessed?

Kotlin, the much-hyped programming language that almost became the most credible and complete alternative to Java for Android app developers is still in the debate and discussion across developer forums. Well, ever since it was unveiled in 2011 as the open-source programming language for general purposes, the graph of popularity and attention continued to soar higher. The biggest draw for Kotlin is that it offers all the goodness of Java while it comes without most of its shortcomings. That’s precisely why it is said to have the edge over Java. 

From simple, clean and stripped of code and syntax to an array of sophisticated and developer-friendly features like data classes, null safety, operator overloading, and many others, Kotlin in many regards has been the most efficient programming language so far. But comparing with Java is a big thing, as it is the new entrant in comparison to the decades-old, expansive Java ecosystem spread across millions of apps and websites. But still, these eight features can convince you that Kotlin is ahead of the curve of Java.  

Data classes

Any Java developer is acquainted with the model class they need to create for getters and setters. This is where Kotlin looks utterly different as app developers now can do away with the complexity by merely adding data in front of the class, which will work as the model class. This model class without any getters and setters will be able to reach out to the members on its own.

Null Safety

Finally, Kotlin comes with a special security feature called null safety to safeguard the code from data classes. With Java, app developers while accessing null references at various occasions actually need to use a null reference exception. Kotlin does away with this difficulty through the type system that eliminates NullPointerException. This helps in boosting data consistency. 

Single type system (almost)

Kotlin offers a typing system that is much simpler. It comes with almost one protocol as a language that already has been praised by millions for valuable features like null support, type inference, universal guards, etc. It is also known for a single and comprehensive type system. 

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It offers a supertype representing all non-nullable types that are called Any. This supertype works for every type, including the nullable. Here the echo of Java is still audible since there is a similar concept of superclass ruling all classes in Java. But with Kotlin, the type system becomes useful and straightforward for the developers. 

In Kotlin, there is also a subtype of all types called nothing. This type can represent any type without any instance of nothing. Obviously, this is an entirely new concept for even many seasoned Java developers.  

In Kotlin, these two types basically make the entire type system simple and more organized.

Clean and compact syntax

When it comes to programming language syntax and clarity of the code, Kotlin stands miles ahead of Java. To be more precise, with Kotlin, you can get things done with fewer lines of code. Less code makes Kotlin code more reliable with fewer errors and bugs. 

Apart from this, lean and clean code offers an array of advantages like easier maintenance, ease of reading, ease of incorporating changes at times of need, and more. 

Extension functions

As a fully equipped programming language, Kotlin comes with a bucket of Standard Library Functions that help extend and expand the existing class. This extensibility is one of the key aspects of Kotlin programming language. The extension functions of the Kotlin library actually help with new functionalities. 

Streams and its collections

If you are into Java development, you must have worked with the Java Stream API and lazy loading feature. Apart from providing both of these features, Kotlin actually delivers a more expressive and versatile collection of APIs. These APIs can help you do away with many difficulties. 


Immutability is one of the key features of Kotlin. According to this feature, any object or its variations cannot be changed once they are created. This is why, if you are changing the case properties of any object, you need to create a separate clone of the entire object or its variables. The immutability, unlike Java, goes well with Kotlin as the language is threaded in a safe manner and there is no concurrency as well as synchronization issues.

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Immutability for Kotlin works like a magic wand and makes things simpler and smoother. 

Operator overloading

This is another key feature of the language. With Kotlin, we can now implement several operators based on our types. These are the operators that are represented symbolically through + or *, for instance. Applying the operator is very easy as it allows us to give a fixed name to core and extension function. Finally, the overloaded operator also needs marking by the operator modifier. 


All the above features clearly indicate how Kotlin makes a far better value proposition over Java for Android developers. Since it is still fairly new, it will take time to grow in stature and popularity and eventually to take over Java. 


Juned Ghanchi

Juned Ghanchi is a chief marketing officer at IndianAppDevelopers. A mobile app development company in India specializes in providing web and mobile app solutions to the startups and big brand companies.  He regularly publishes expert presentation and technology tips on various blogs and magazines.

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