Special Offer - Enroll Now and Get 2 Course at ₹25000/- Only Explore Now!

All Courses
kotlin Interview Questions and Answers

kotlin Interview Questions and Answers

July 12th, 2019

In case you’re searching for kotlin Interview Questions and answers for Experienced or Freshers, you are at the correct place. There is parcel of chances from many presumed organizations on the planet. The kotlin advertise is relied upon to develop to more than $5 billion by 2021, from just $180 million, as per kotlin industry gauges. In this way, despite everything you have the chance to push forward in your vocation in kotlin Development. GangBoard offers Advanced kotlin Interview Questions and answers that assist you in splitting your kotlin interview and procure dream vocation as AWS Developer.

Best kotlin Interview Questions and Answers

Do you believe that you have the right stuff to be a section in the advancement of future kotlin, the GangBoard is here to control you to sustain your vocation. Various fortune 1000 organizations around the world are utilizing the innovation of kotlin to meet the necessities of their customers. kotlin is being utilized as a part of numerous businesses. To have a great development in kotlin work, our page furnishes you with nitty-gritty data as kotlin prospective employee meeting questions and answers. kotlin Interview Questions and answers are prepared by 10+ years experienced industry experts. kotlin Interview Questions and answers are very useful to the Fresher or Experienced person who is looking for the new challenging job from the reputed company. Our kotlin Questions and answers are very simple and have more examples for your better understanding.
By this kotlin Interview Questions and answers, many students are got placed in many reputed companies with high package salary. So utilize our kotlin Interview Questions and answers to grow in your career.  
Google announces kotlin as the officially supported programming language for android application development. Kotlin is a cross platform and general purpose programming language created with type inference. It is designed to fully interoperate with java, the standard library of JVM version depends on java class library. It is modern, expressive, safe to code and is interoperable. Kotlin is well optimized for android development with having support for Android studio and Android KTX.

Q1) What is Kotlin?

Ans: Kotlin is a free open source project licenced under Apache2.0, it is a statically-typed programming language which runs on the JVM. It can be compiled by Java source code or LLVM compiler.

Q2) Who is the developer of Kotlin?

Ans: Jetbrains is a software company which created kotlin. This company focuses mainly on tools that are specifically for project managers and software developers.

Q3) Why you should shift from Java to kotlin?

Ans: Kotlin is very simple compared to java, it minimises redundancies in code and offers many useful features that java doesn’t support.

Q4) What are the features that kotlin support and java doesn’t?

Ans: The following are the important features that kotlin supports over java:

  • Operator Overloading
  • Coroutines
  • Null Safety
  • Range expressions
  • Companion Objects
  • Smart casts

Q5) What are the programming types that Kotlin supports?

Ans: Kotlin supports two types of programming they are:

  1. OOPS
  2. Procedural Programming

Q6) List the number of constructors available in Kotlin?

Ans: Constructors are of two types they are:

  1. Primary constructor
  2. Secondary constructor.

Q7) How to handle null exceptions in Kotlin programming?

Ans: Null expectations in Kotlin can be handled using Elvis Operator.

Q8) How can data class be used in Kotlin?

Ans: Data class supports basic data types, it doesn’t have any other functionality.

Q9) How do you export code from Java to Kotlin?

Ans: JetBrains software provides an inbuilt tool called jetbrain idea, it helps in exporting the code from java to kotlin.

Q10) How do you declare a variable in kotlin?

Ans: Declaration of a variable in kotlin differs from java, below is the format for that:
val s: String = “Hi”
var x = 5

Q11) Does Kotlin programming allow macros?

Ans: Kotlin developers are facing difficulties in including macros in the language, so offering support for macros in kotlin is not possible.

Q12) How do you declare ranges operator in kotlin?

Ans: Ranges operator is used to iterate through a range, the operator is of form (..), for example
for (i in 1..15)
The above format will print the output as a range of numbers from 1 to 15.

Q13) Describe the use of extension function?

Ans: Extension function is useful in extending a class without having the need to inherit from the class.

Q14) Name the extension methods Kotlin provides to java.io.File?

Ans: Below listed are the extension methods that kotlin provides to java.io.file:

  • readText(): used for reading the content of a file.
  • forEachLine() : used for reading a file line by line in Kotlin
  • readLines(): Used for reading lines in file to List
  • bufferedReader(): Used for reading the contents of a file into BufferedReader
  • readBytes() : Used for reading contents of file to ByteArray

Q15) What is the difference between Const and Val?

Ans: Const is primarily for compile time initializations and val is used for runtime initializations.

Q16) List some of the key modifiers in kotlin?

Ans: Kotlin has a list of few key modifiers, they are:

  1. public
  2. private
  3. protected
  4. interval

Q17) How do you differentiate var and val in Kotin?

Ans: A variable defined with var are mutable, it is formatted as
var a: Int=3
a *= a
A Variable defined with Val are immutable, it is formatted as:
val b: Int = 6

Q18) Is kotlin strongly typed?

Ans: Kotlin is similar to java with equally strongly typed. Kotlin compiles down to pure Java byte code.

Q19) What is the purpose of creating kotlin?

Ans: Kotlin was created by a Czech company named after JetBrains and the actual purpose of creating it was to solve their internal development problems.

Q20) Which companies use kotlin?

Ans: Kotlin is used by major companies around the globe, here are some of them:

  • Postmates
  • Atlassian
  • Evernote
  • Corda
  • Spring by pivotal
  • Coursera
  • Pinterest
  • Uber.

Q21) What is the latest version of kotlin?

Ans: Currently kotlin is updated to version 1.3.30. This version has a bug fix and tooling update for 1.3. This release focuses mainly on KAPT performance, kotlin Native and improvements for IntelliJ IDEA.

Q22) How is kotlin integrated with Gradle?

Ans: With the release of Gradle 5.0, kotlin offers support for gradle. You can have a look at it here: Gradle Kotlin DSL v1.0

Q22)  what is Kotlin?

Ans: Kotlin is an open source statically-typed programming language developed by JetBrains that is strongly supported Java Virtual Machine (JVM) in an Android ecosystem along with Java.

Q23)  Name some of the features that have Kotlin but not in present in Java?

Ans: kotlin has many features that are not present in Java. The following are a few features:

  • Null safety
  • Operator overloading
  • Extension functions
  • Data classes etc

Q24) Why you should switch to Kotlin from Java?

Ans: Kotlin is the easiest language compared to Java as they reduce redundant code in an application. Kotlin offers new features that Java doesn’t support.

Q25) What type of programming does Kotlin support?

Ans: Kotlin will support two kinds of programming listed below:

  • Object-Oriented Programming similar to Java
  • Procedural Programming

Q26) what is the use of extension functions in Kotlin?

Ans: Extension functions are used to extend the class without inheriting from the class.

Q27) What is the default visibility modifier and also list the different types of modifiers?

Ans: The default visibility modifier is public. The following are a few types of modifiers:

  • internal
  • public
  • private
  • protected

Q28) What is Kotlin’s target platform? Is Java-kotlin interoperability possible?

Ans: The target platform for Kotlin is JVM. Java is 100% interoperable with Kotlin because on compilation both produce the same bytecode. Therefore Java code can be called from Kotlin and the reverse is also possible.

Q29) How to declare a Kotlin variable?

Ans: In the Kotlin the variable declaration:
Val s: String = “Hello world!!”
var p = 15

Q30) What is the difference between Val and var declaration?

Ans: Val is similar to final modifiers in Java they can’t be changed. Var can be reassigned but the data type cannot be changed. An example is shown below:
Val y: string = “hi”
Var x = 2

Q31) How to convert a String to an Integer?

Ans: toInt()  is the method used to convert string to an integer. The following is an example:
fun main(args: Array<String>) {
Val s: String = “Hi”
var x = 5
x = “8”.toInt()

Q32) Is it possible to migrate the code from Java to Kotlin?

Ans: Yes, it is possible to migrate the code from Java to Kotlin. JetBrains IDE is required to perform this action as it facilitates the conversion.

Q33) What are the different types of constructors in Kotlin?

Ans: There are two types of constructors in Kotlin namely:

  • Primary constructor
  • Secondary constructor

Primary constructor: In this type of constructors class header is declared after the class name.
Secondary constructor: These type of constructors are declared inside the body.

Q34)  Does Kotlin support primitive Data types?

Ans: No, Kotlin doesn’t support primitive Data types as in Java

Q35) Mention the structural expressions in Kotlin?

Ans: The following are the three structural expressions in Kotlin.
Return: It returns value from the functions by default.
Break: terminates the loop condition.
Continue: precedes you to the next enclosing loop.

Q36) What are the data classes in Kotlin? How are they defined?

Ans: In kotlin, we create a class to store huge data, called data class. To create a data class you need to add a keyword called “data” on the class. The following is an example:
data class Book(var name: String, var authorName: String)
fun main(args: Array<String>)
Val book = Book(“One night at the call center”, “Chetan Bhagat”)

Q37) what operator is used to handle null exceptions in Kotlin?

Ans: Elvis Operator is used for handling null expectations in Kotlin.

Q38) What are High-Level Functions in Kotlin?

Ans: Functions that accept another function are called high order functions. Kotlin regards its functions as citizens of first class and passes the variables to other function.

Q39) What are Coroutines?

Ans: Coroutine is a light-weight thread that doesn’t require any context switching on the processor and will not map on native threads. This is the reason why they are fast in processing the requests.

Q40) How to create static methods in Kotlin?

Ans: There is no static method in Kotlin but, to create a static method we use a keyword called object. The following is an example to create a static method:
class kotlin {
companion object {
fun x() : Int = 45

Q41)  What are the advantages and disadvantages of Kotlin?

Ans: The following are a few pros and cons in using Kotlin:



Kotlin is similar to Java and hence it is easy to learn

Kotlin doesn’t provide static modifiers and hence cause problems to the Java developer

Can be usedin any applications used in any device such as the desktop. Web Server and mobile phones

In kotlin functions can be declared and called in multiple places and so they might be a sort of confusion

It is a functional language based on JVM hence it helps in optimizing the code