Java or Kotlin- Which one to choose for Application Development?

Developing Android apps is an enormous way to boost your company's performance, but deciding which programming language to use is the actual challenge. It is self-evident that Java is the greatest for many of us because it is widely used and praised. However, with the introduction of Kotlin, programmer's apparent faith in Java is somewhat devastated, and they begin looking for answers to numerous questions.

Is Kotlin better than Java for Android Development? Which is more feasible to use? Is this the age to switch to Kotlin and leave Java behind? Why are they different, and why should we decide which one of Java and Kotlin is our preference? Tons of questions and no clarity. But this article will provide a clear space to think, compare and choose.


Java was first used in 1995, and it is an object-oriented programming (OOP) language. Sun Microsystems, which Oracle eventually acquired, developed Java. As a result, we must utilize Java applets inserted as a plugin, which is not recommended to run a Java program in the browser. As a result, Java is mostly employed in the creation of individual apps or back-end systems. James Gosling created Java, and OpenJDK was the most popular implementation. The extension used for Java is (.java).


Kotlin first appeared in the year 2011 and was later officially released in the year 2016. It is one of the latest programming languages and was developed by the programmers from IDE Jet Brains. The programmers made sure to add new and modern features to the language, and it is considered an open-source language. Kotlin is a statically typed programming language similar to Java and C++ that runs on the JVM (Java Virtual Machine). Still, it can also be turned into JavaScript, Android, and Native for use on iOS. Kotlin has a low learning curve and is entirely compatible with existing Java stacks. It's simple to go from Java to Kotlin if you are from programming background. The extension used for Kotlin is (.kt).

Major Difference Between Kotlin And Java




Functions of Extension

In Java, we must create a new class and inherit the parent class if we want to enhance the functionality of an existing class. As a result, Java does not support extension functions.

Kotlin gives developers the ability to add new functionality to an existing class. By prefixing the name of a class to the name of the new function, we can build extend functions.

Null safety

NullPointerExceptions are a huge fuss for developers. The function allows users to assign any null to any variables. It allows the user to set null to any variable, but it produces a null pointer exception when accessing an object reference with a null value, which the user must handle.

By nature, all sorts of variables in Kotlin are non-nullable (that is, we can't assign null values to any variables or objects). Kotlin code will struggle to establish if we attempt to assign or return null values. If we need a null value, we must declare it as follows: Int? = null

Data classes

Let's say we need a class in Java that only holds data and nothing else. Constructors, variables to store data, getter and setter methods, hashcode (), function toString() { [native code] }(), and equals() functions are all required.

Suppose we need to have data-holding classes in Kotlin. In that case, we may define a class with the keyword "data" in the class declaration, and the compiler will take care of everything, including constructing constructors, getter, and setter methods for various fields.

Type Interference

We are required to specify the following variable while declaring.

We are not required to specify the type to a variable based entirely on the assignment that will be needed. But if we want to specify it, we can do that of our own will.

Functional programming

Java does not have the support of functional programming till Java 8. Therefore, it only supports the subsets of Java 8 and other features only while android application development.

Kotlin differs from Java as it is a mixture of both the functional and procedural programming language with many methods useful in lambda, overloading, lazy evaluation, and operator and higher-order functions.

Also Read: Difference Between Java And PHP


Lastly, it delivers an outline of the Java vs Kotlin contrast. After reading this Java vs Kotlin post, you will have an enhanced understanding of these two languages. Even if Java offers a few benefits over Kotlin, we can continue with Kotlin for Android application development without thinking about the compilation time.