Kotlin VS Java

Java enjoyed an undisputable reputation as a programming language, especially for android applications. Developers and software development companies have always preferred Java. However, lately, there arose a need for modern language in Android Development, and then Kotlin was introduced. Java is a modern programming language for developing android apps and loved by developers of an android app development company ever since it was announced. Let’s have a detailed understanding of Kotlin vs Java.



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Kotlin was introduced by a team from JetBrains to the developing world to make the Java codes more productive. Later, in 2018, it was announced as an official language for Android Development. This language runs on JVM (Java Virtual Machine), which runs in browsers and can also be compiled in JavaScript. Developers develop native apps using Kotlin, and with the help of IDE, can build cross-platform apps as well.


Java Logo

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Java is a robust, simple, and object-oriented programming language best suited to develop Android Apps. Java Microservices helps development companies & developers build web apps, embedded systems, server apps, big data, and more. Sun Microsystems released this language in 1995, and it is now a property of Oracle. Also, most of its elements are available in open-source. Most of the apps and their significant shares are based on Java and are now the third most popular language on Github.

Pros and Cons of Kotlin


  • Kotlin enables the development of clean APIs. 
  • The much-needed null is present in the type system of Kotlin. Android uses the null to represent the absence of value. 
  • Java frameworks and libraries can be used in Kotlin with the help of Java bytecode. This makes the transition of Java to Kotlin seamless. 


  • Kotlin has a steep learning curve and short syntax. 
  • The language is relatively new, and finding experienced developers in this language is a challenging task. 
  • In most cases, the compilation speed of Kotlin is slower than Java. No denying the fact it beats Java in most cases.

Pros and Cons of Java


  • It has a comprehensive open-source system.
  • The programming language yields a rapid build process. Developers can code in less time. 
  • When it comes to Android development, developers find plenty of Java libraries at their aid. 
  • Java apps are compact and lighter, even more than apps developed using Kotlin. The best choice is to outsource your project to a Java development company. 


  • Java has some inherent limitations, so the programming language experiences some problems with Android API design. 
  • Java is a type-heavy language that means long codes are required, which ultimately increases errors. 

Kotlin VS Java

Let us see the differences between the two programming languages and which language wins in Kotlin vs Java.

  • Speed

Java and Kotlin offer similar coding speeds. 

Moreover, developers have to code less when using Kotlin because of its laconic constructions. However, when there is a need to find a solution for something, it requires more time than Java. If you think abstractly, Kotlin is suitable. 

  • Performance

As far as memory usage is concerned, comparing both languages is a daunting task since both the languages compile to Bytecode. 

Due to the extra added features, Kotlin is more functional as compared to Java. At times the added features make the compilation of Kotlin slower. On the contrary, Java is a simple language with few features, so the compilation is quick. 

  • Popularity

Java attracts the interest of developers more than Kotlin. One of the major reasons behind it is the long life of Java. 

Also, Java requires less cognitive investment when it comes to the learning curve. That said, Java wins when it comes to popularity.

  • Community

The core community of Kotlin includes Russian since the programming language comes from Russia. Also, the community of Kotlin is 20 times smaller as compared to Java. 

  • Talent Pool

Almost 8% of professional developers choose Kotlin language for development. Although Java is the most loved technology, several developers have stated that they would prefer to continue developing apps using Kotlin. 

Also, Kotlin helps developers earn more money as compared to Java. That said, when it comes to Talent Pool, Kotlin wins the battle. 

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What Java Has That Kotlin Does Not? 

  • Checked Exceptions

For developers who want to write powerful codes with the ability to recover from errors, Java’s checked exception feature is coveted. Though Kotlin also does away with the developers and helps them aid code conciseness, Java is highly favoured. 

  • Static Members: 

Kotlin doesn’t have any provision for the static members, whereas Java establishes an instance of a static member that is then shared across every class instance. 

  • Wildcard-Types: 

There are several Wildcard uses, including the parameter, type of field, or local variable. Join doesn’t provide wildcard types, whereas Java enables the developers to use this system for extended functionality. 

  • Ternary-Operator: 

Unlike Kotlin, Java has a Ternary Operator that works like basic if the statement can evaluate the true or false of a specific condition. 

  • Primitive Types That are not Classes: 

Float, chat, double, and type are the four primitive types among eight, which serve the sole purpose of containing the simple, pure value of a kind. Several Java operations are pre-defined and are not instantiated by an object from a class or a struct. 

Also, read our blog on Java Software Development – Your Nearshore Solutions

What Kotlin Has That Java Doesn’t? 

  • Extension Functions: 

Kotlin’s extension functions enable importing a reference to the view in an activity file and then allows developers to work with that view as a part of the activity. Establishing an extension function is very easy in Kotlin, just as prefixing the name of any class. 

  • Smart Casts: 

Kotlin is not like Java, and it lets developers automatically handle redundant casts without the need of checking type or having to cast it inside a statement. 

  • String Templates: 

The string templates of Kotlin enables developers to assign any dynamic value directly to the strings. They can also easily print statements in Kotlin using the templates. 

  • First-Class Delegation: 

Kotlin natively supports delegation patterns, and it doesn’t require any boilerplate code. It offers an efficient alternative to the inheritance of implementation. 

  • Companion Objects: 

If the code requires a property or function to be tied to a class instead of to instances of it, it can be declared effectively inside the companion object. The companion object is a singleton, and the developer can easily access it through the name of the containing class. 

Will Kotlin Replace Java for Android App Development?

android app development

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There have been a lot of arguments going around after the release of Kotlin. A few are saying that Kotlin will entirely replace Java as far as android app development is concerned. However, it is not true. The programming language may be beneficial, and the developers might like how it does everything, but it cannot completely replace Java.

After deeming Kotlin as a first-class android development language, Google realised that it was just an additional language in the market. Kotlin cannot replace the existing support of Java.

Closing Notes

In this comparison of Kotlin VS Java we have seen that even if they are similar in several aspects; they serve different purposes. If you are looking to develop an android app, we recommend you hire an Android developer. With their knowledge and expertise, they can guide you in the language that will be best suited to your requirements.

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#java #kotlin #javavskotlin #mobileappdevelopment #androidappdevelopment #androidapp #prosandcons #speed #performance #popularity #community #talentpool

Kotlin vs Java: INFOGRAPHIC

Kotlin VS Java Infographic



About Ami Dias

Ami Dias
Ami Dias is working as the Digital Marketing Officer at WeblineGlobal. She is a technology enthusiast who writes a lot of blogs and articles specifically for new-age tech. When she is not working, she likes to go for a long drive and she also travels to various destinations. She is an advocate of a healthy lifestyle and practices yoga with meditation. If you need any elaboration or assistance on the topics she is writing then feel free to drop an email to info@weblineglobal.com