Kotlin vs. Java: Why Kotlin is going to replace Java

Kotlin vs. Java: Why Kotlin is going to replace Java

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It is not quite a surprise, but when you choose developers to work on your custom Android application, the specific technology they use is essential for you. The two most commonly used languages for Google now are Java and Kotlin. Now it's official! Google made Kotlin a first-class language for writing Android apps, so it may seem, at first, a matter of small importance what language your team’s coding on. However, further consideration shows that programming language can also cut down some of your time and expenses.

Java is already fading in popularity, with Google replacing it, but what is replacing Java? In 2011, as an unveiled version, Kotlin first appeared as a new language for Java Virtual Machine from a team of Saint-Petersburg programmers called JetBrains. The reason they decided to come up with a new “spinning wheel” for Android development is quite easy to understand; apparently, there are a few. First of all, Java has been around for 22 years already (a long term for a programming language), which is why there are loads of features that can not be implemented due to Java's massiveness and obsolescence.

Since Kotlin was introduced it has become a major threat to Java. But what exactly is Kotlin, and how do its functionalities compare to those of Java? Is Kotlin going to take over most of the tasks that Java performs? Keep reading to find out the answers to these questions.

Reasons to Use Kotlin for Android

Reasons to Use Kotlin for Android | TechMagic.co

Let’s check the reasons and see why experts are figuring out how to replace the existing Java with Kotlin and wondering, will Kotlin take over Java?

  1. It’s Android-focused. Kotlin was written by the same folks who created popular integrated design environments (IDEs), so its background comes from mobile industry pros looking for solutions to specific problems.
  2. Switching from Java is extremely easy. Will Java be replaced? In IntelliJ or Android Studio, converting Java files to Kotlin requires installing the Kotlin plugin, adding it to the Gradle build files, and clicking convert.
  3. Extension functions, which help in building really clean APIs and solve a bunch of other problems.
  4. It has null in its type system. Nullability problems are common in Java, and Android uses null quite a bit to represent the absence of a value. Basically, having a null point exception can kill an app. Kotlin solves this by having null right in its type system, not forcing developers to use some kind of workaround.
  5. Simple syntax. Less code to write. Java isn’t known for being the most succinct language. While that isn’t a con in and of itself, when you’re programming for Android and using a bunch of common idioms, a verbose code can lead to more chances for bugs. When you can write less code (at least 20%) with a more concise language, there are fewer opportunities for errors, and it’s less tedious for developers, which is a good reason for a replacement for Java.
  6. Type-safety language. In Kotlin, every class is a function, and vice versa; more to this, same as Swift for iOS, Kotlin for Android has optional types, which help with all the safety check-ups.
  7. The Anko library and plenty of other Kotlin-based projects. The Anko library is a Kotlin source file that eliminates a few XML-related headaches, too. There are over 2,000 Kotlin projects on GitHub, with everything from frameworks to build systems to libraries.
  8. It avoids extra garbage collection, which is a common problem in Android development that adds inefficiency to Java code.

Switching Between Java and Kotlin Languages: Why to Replace Java with Kotlin

Switching Between Java and Kotlin Languages: Why to Replace Java with Kotlin | TechMagic.co

The world we live in is getting quite unpredictable on many occasions, and in terms of mobile application development, sometimes there is a need to change the team you have been working with.

Let’s say you used to work with the outsource team, but now there is a request for an in-house development for your project. How difficult would it be to make a "translation" from one language to another? Again, the answer really depends on the tech your previous engineers used. If we do Kotlin to Java replacement as an example, then there undoubtedly is a solution. JetBrains has created a Java-Kotlin converter that helps resolve this issue; however, some errors still occur during the Kotlin replace Java conversion process, so it has to be monitored. Some of the operations even have to be manually set.

On the downside, the Kotlin replacing Java conversion process would be yet more stagnant and painful, as not all the functions, methods, and variables could be converted. Perhaps the quickest fix for the new team you cooperate with would be to continue writing in Java if possible.

Also, the possibility of conversion to another Java replacement language would depend on your project’s size. There are, generally speaking, three types of projects: small, medium, and large.

  • Small projects take around 160-200 hours, and if there is no complex architecture, then it’s possible that Kotlin is going to replace Java;
  • Medium projects consist of up to a 5-month development process and are pretty inconvenient to convert;
  • Is Kotlin going to replace Java in large projects? Such projects development starts from a 5-month term, and projects of this category are totally impossible to convert into another language.

What can I use Kotlin for?

With the support it receives from Google, Kotlin is rapidly growing. Kotlin was designed to be more operational and thus can be interchanged with Java. This makes it possible for developers to create Kotlin code within Java code. Doing this facilitates the migration of applications from Java to Kotlin. The main uses of Kotlin include:

  • Kotlin can perform all tasks that Java can, so you can use it to create native Android applications;
  • Kotlin can be used to create JavaScript enabled apps. These applications can work in a browser;
  • Another use for Kotlin is to create HTML sites. Simply use the corresponding Kotlin template;
  • Kotlin can be used to build backend applications that require concise coding. Kotlin uses coroutines to create web applications;
  • Because Kotlin compiles to JavaScript, you can use it with Node.js for server-side coding;
  • Kotlin can be used to build enterprise applications because it has the same basic functions as Java. Since Kotlin targets JVM, any application that is created with it is almost the same as one built using Java;
  • Kotlin can be used to build a client-side web;
  • You can use Kotlin with a Java UI framework for web development.

What can I use Java for?

Java has been around for more than 20 years. It is the primary programming language used to create Android applications. The main areas of use include:

  • It is the official language for building mobile applications as it can be used in combination with other software, including Kotlin. Java provides better security for Android applications making it a popular choice for Android developers.
  • Many desktop applications can be created with Java as it provides many advanced elements. Java is compatible with GUI development as well.
  • Java provides support for developing web-based applications. The easy coding and high security it provides makes a good programming language for many large applications.
  • Java is a favorite choice when designing enterprise applications. Java EE is useful for web-based applications and other web services. It has been used to create applications for the financial industry. Java is reliable for any large and scalable business applications.
  • Java is a formidable tool when designing 3D games. This is possible because it is supported by the JMonkeyEngine.
  • Java can be used to create some Big Data applications. Programming languages like Scala are available thanks to Java.


Will Java be replaced by Kotlin | TechMagic.co

Will Java be replaced by Kotlin? Undoubtedly, Kotlin may have its pros and cons, but plenty of features became practicable once Kotlin came in. Unlike the Swift programming language (an internal Apple project which became an open-sourced one), Kotlin isn't owned by Google. The language will continue to be developed and supported by JetBrains — the company is partnering with Google to set up a non-profit Kotlin foundation to shepherd the language.

Kotlin also continues to target other platforms: the language is designed to run as native code on iOS and Macs and compiles to JavaScript for web development. Kotlin is the official Android language for the future. A concise way to code for Android in a smarter way. Kotlin is gaining more popularity among developers, as it’s also supported by Google. Sure, one of the reasons why Kotlin is a popular choice for developers is because it can be used with JavaScript. But as it has less code, it is a better option. A shorter syntax means developers can create applications at a faster rate. Will Kotlin Replace Java for Android? Considering the facts, it looks like an inevitable stage.

Another reason why Kotlin is gaining an advantage over Java is that it uses the best programming paradigms. Switching from Kotlin to Java is easy. But because Kotlin works with JVM, it still relies on Java, especially in large projects. Just like any coding language, Kotlin has a learning curve that's quite a challenge. The best part is that you can use codes for Java and Kotlin on each application or project you work on. So while Java is still relevant, Kotlin is a tool that every developer should learn, especially since you need less coding.

Romana Kuts
Romana Kuts
Content Marketing Manager at TechMagic. Mainly focused on content marketing, SEO optimization, and media relations.
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