Kotlin vs Java is one of the trending topics these days. When it comes to Android app development, Java language is the one which first hits the mind of coders. And, Java programming language is everywhere.
However, Kotlin has arrived now with significant improvements in android app development as we have already seen this in the previous article “How android app development became Kotlin first”.
So, both Java and Kotlin offer strong competition to each other. Thus, we have done a great comparison of both Kotlin and Java language.
This article aims to answer some questions related to both Kotlin as well as Java language. We will discuss benefits, major differences based on various parameters, technical differences and much more.
Java & Its Benefits
Java is a programming language created by James Gosling. Using this, we can create any type of program, it is also compatible with almost any type of machine. It is in Linux operating systems, Windows and also for mobile devices in Android.
Currently, Java has one of the most important and largest communities in the world. This language, both on the Internet and in the computer field, is very important. Java can be used to do almost anything.
- Java is platform-independent and easy-to-learn
- It allows you to create modular programs and reusable code
- Java provides network-centric programming
- Carries security features and high performance
- It is robust, dynamic and programmer efficient language.
Kotlin & Its Benefits
Kotlin is a programming language created by JetBrains. It was announced at Google I/O as the second official language of Android app development. Since then, it has been steadily maintaining partnerships with Google cloud platform, Gradle and the Spring framework. Its creators believe that developing an Android application can be faster and more fun, and its community is growing continuously.
- It is Open Source & costs nothing to adopt
- The programs are written using Kotlin use existing Java Frameworks & Libraries
- Kotlin can be learned easily and it is approachable
- Kotlin’s null-safety is great
- Automatic conversion of Java to Kotlin
- Code reviews are not a problem in Kotlin
Also Read: Benefits of Android App Development
Kotlin Vs Java
It is the core purpose of Kotlin. From the beginning, the intention of the project was to use existing knowledge and experience so that all libraries are available to Kotlin programmers. Developers can simply write modules in Kotlin that work perfectly within the existing Java code. By issuing the Bytecode, a Kotlin compiler allows the two languages to work in unison in the same project.
Before generics, raw types were used quite frequently. Raw types allow backward compatibility, but raw types can generate a CastClassException and the error will occur during execution and not at the compilation stage. Kotlin does not allow unformatted types and, as a result, produced a more secure code for the type.
Built-in Null Safety
The Kotlin type system has zero built-in security. The infamous NullPointerException is largely responsible for the development errors of Android and Java. Android is based on null to represent the absence of a value, but null can easily destroy an application. Kotlin solves this problem by incorporating inherent null security. This addition prevents developers from writing additional code to solve the problem.
Brevity is a crucial factor in productivity. Writing large projects becomes easier when a developer receives more power for each line of code. A key observation here is that Kotlin does not overlook understanding for brevity. The syntax is concise and still substantially legible.
Many developers praise Kotlin for being concise. This is a quality that Java is not known for; however, readability must always take precedence over concision. Yes, the succinct nature of Kotlin simplifies the work of a developer and leaves less room for error, but Kotlin does not practice conciseness for the sake of conciseness.
The exception feature checked in Java can be problematic. Checked exceptions are when the compiler forces the caller of a function to capture or (re-throw) an exception. The fact is those proven exceptions are often unnecessary and cause empty capture blocks. Proven exceptions that do not exist are a nuisance for developers because they are forced to check the code to identify a possible exception that never occurred. As a solution, Kotlin eliminated them completely, which again minimizes verbosity and improves type security.
Besides this, both Kotlin and Java have various technical differences. Some of them are listed below:
1) Extension Functions
Kotlin allows developers to extend a class with new functionality through extension functions. These functions, though they are available in other programming languages such as C #, are not available in Java.
Creating an extension function is easy in Kotlin. It is done by prefixing the name of the class that must be extended to the name of the function that is being created. To call the function in the instances of the extended class, one needs to use the notation “.”
2) Code Conciseness
The comparison of a Java class with an equivalent Kotlin class demonstrates the conciseness of the Kotlin code. To perform the same operation that the Java class does, a Kotlin class needs less code.
The Kotlin Android extensions allow you to import a reference to a view in the activity file. This allows you to work with that View as if it were part of the Activity.
3) Data Classes
Full-sized projects have several classes that are only meant to contain data. Although these classes have little or no functionality, a developer must write a lot of repetitive code in Java.
Generally, a developer needs to define a constructor, several fields to store the data, obtain and set functions for each of the fields, and functions equal to (), hash code () and toString ().
Kotlin has a very simple way to create such classes. The developer should only include the data keyword in the class definition, and that’s it! The compiler will take care of the entire task on your own.
4) Checked Exceptions
An important difference between Java and Kotlin is that the latter has no provisions for the verified exceptions. Therefore, it is not necessary to capture or declare exceptions.
If a developer working on Java finds it annoying to use the try/catch blocks in the code, the omission made by Kotlin can be considered a welcome change. However, it is the opposite if the developer believes that the checked exceptions encourage the recovery of errors and the creation of robust code.
5) Inline Functions
The variables that are accessed in the body of the function are known as closures. Making use of higher-order functions can impose several penalties at runtime. Each function in Kotlin is an object and captures a closure.
Both classes and function objects require memory allocations. These, along with the virtual calls introduce runtime overhead. Such additional overload can be avoided by aligning lambda expressions in Kotlin. An example of this is the lock () function.
Unlike Kotlin, Java does not provide support for online functions. However, the Java compiler is able to perform inline using the final method. This is because the final methods can not be overridden by subclasses. In addition, the call to a final method is resolved at the time of compilation.
6) Ternary Operator
Unlike Kotlin, Java has a ternary operator. The Java ternary operator simply works like a basic if statement. It consists of a condition that evaluates to true or false.
Moreover, the Java ternary operator has two values. Only one of them is returned depending on whether the condition is true or false. The syntax for the Java ternary operator is:
In generic code, ‘?’ represents an unknown type. It is known as the wildcard. There are several uses of a wildcard, including as the type of a field, local variable, or parameter.
While Java’s type system offers wildcard types, Kotlin doesn’t. However, it has two different things; declaration-site variance and type projections as an alternative to wildcard types.
7) Non-private Fields
Encapsulation is essential in any program to achieve a desirable level of maintenance.
By encapsulating the representation of an object, the way in which the callers interact with it can be imposed. In addition, it is possible to change the representation without the need to modify the callers, as long as the public API remains unchanged.
Non-private fields or public fields in Java are useful in scenarios where people who call an object need to change according to their representation. “It simply means that such fields expose the representation of an object to callers. Kotlin has no private fields.”
8) Support for Constructors
A Kotlin class, unlike a Java class, can have one or more secondary constructors in addition to a primary constructor. This is done by including these secondary constructors in the class declaration.
9) Primitive Types
There are 8 primitive data types, including char, double, float, and int. Unlike Kotlin, variables of a primitive type are not objects in Java. This means that they are not an instantiated object of a class or structure.
10) Smart Casts
Before an object can be converted to Java, it is mandatory to verify the type. This is also true in scenarios where it is obvious to throw the object.
Unlike Java, Kotlin comes with the function of intelligent molds, which automatically handle such redundant releases. It is not necessary to issue within a statement as long as it is already verified with the “operator is” in Kotlin.
11) Static Members
Kotlin does not have provisions for static members. However, in the Java programming language, the static keyword reflects that the particular member with which the keyword is used belongs to a type in itself to an instance of that type.
It simply means that one and only one instance of that static member is created and shared in all instances of the class.
12) Null Safety
One of the most annoying problems related to Java for developers is NullPointerExceptions. Java allows developers to assign a null value to any variable. However, if you try to use an object reference that has a null value, the NullPointerException arrives!
Unlike Java, all types are not nullable in Kotlin by default. If the developers try to assign or return a null value in the Kotlin code, it will fail at the time of compilation. However, there is a path around. To assign a null value to a variable in Kotlin, it is necessary to explicitly mark that variable as nullable. This is done by adding a question mark after the type.
13) Native Support for Delegation
In programming terminology, Delegation represents the process in which a receiving object delegates operations to a second delegated object. Kotlin supports composition over the inheritance design pattern by the first-class delegation, also known as implicit delegation.
Class delegation is an alternative to the inheritance in Kotlin. This makes it possible to use multiple inheritances. In addition, the delegated properties of Kotlin avoid duplication of code.
Now the question is:
Does Kotlin bring death to java language?
Since Java is a well-known programming language having various open source tools and libraries in order to help app developers.
But no language comes with perfection. In fact, Java itself can be complicated for many. For this, Kotlin has arrived which addresses common programming headaches with its effective solutions and also improve the Java ecosystem.
We now know that Kotlin has become a more stable and congruent development option for Android Studio. Some Android developers seem to believe that Kotlin will expel Java for mobile app development in the near future. On the other hand, some experts consider that Kotlin and Java exist in parallel without one surpassing the other.
In Kotlin vs java discussion, it is Kotlin which is clean, inherently lightweight and less verbose in terms of data classes, getters/setters and writing callbacks. It is specifically designed for improving the existing Java models using solutions to API design deficiencies.
Hence, we can say that Kotlin is not a replacement for Java, it’s an enhancement.
As per the above comparison, it is clear that Kotlin is the winner as it continues to grow day by day. The documentation is very well implemented and it is much better than Java in terms of compatibility, security, syntax and functional programming. Android app developers finally have the pragmatic, modern, and intuitive language they’ve been waiting for. However, it all depends on preferences.
Kotlin is rapidly demonstrating that it is a superior programming language for the development of mobile applications and offers developers a lot of opportunities to experiment with modern programming. Developers can make the transition between OO, FP, scripting and declarative paradigms without any effort, easily establishing a new standard for what a programming language should be able to achieve. So, what are you waiting for, Hire Kotlin developers and get the advantage of this trending language!