Learning a high-level programming language like Java involves the development of coding skills, critical skills, and soft skills. If you are going for a Java interview in a tech giant like Google, Facebook, or Amazon, you need to first get through complex coding tests and exercises to get shortlisted for the next round. To help you out, we are listing some of the most important Java interview questions you must prepare before appearing for your next job interview.

1. Java Coding
Interview
Questions
You Must
Learn

2. Technical job interviews are the hardest to
crack as recruiters’ testa candidate’s
knowledge on multiple levels amongst which
coding remains the primal deciding factor. It
becomes more prominent when you are going
for a Java interview. Java is the most used
programming language that has promising
career potential for professionals with the right
knowledge and skills. Since Java is a highly
dynamic and versatile language, it demands
learner’s todevote adequate time to writing
programs, practicing codes, testing, and
debugging errors.

3. Learning a high-level programming language
like Java involves the development of coding
skills, critical skills, and soft skills. If you are
going for a Java interview in a tech giant like
Google, Facebook, or Amazon, you need to
first get through complex coding tests and
exercises to get shortlisted for the next round.
To help you out, we are listing some of the
most important Java interview questions you
must prepare before appearing for your next
job interview.

4. Top 20 Java
Coding Interview
Questions You
Must Learn:

5. Q-1 Why Java is known as a platform-independent
coding language?
Q-2 How to reverse a string in Java without API
functions? Explain by giving an example.
Q-3 Write down a simple Java program to print the
Fibonacci series.
Q-4 Design a vending machine in Java that vends items
based on 4denominations of coins and returns the coin
if there is no Item.
Q-5 Why is it more secure to store sensitive data like
security numbers or passwords in a character array
than in a String?

6. Q-6 Why should you avoid calling an abstract method
inside its constructor when designing an abstract
class?
Q-7 Write a Java program to check whether a String is a
palindrome or not.
Q-8 Write a program in Java to illustrate scroll up and
down.
Q-9 Write code in such a way that no deadlock should
occur in Java.
Q-10 Write a Java program to remove duplicates from
an array without using the Java Collection API.

7. Q-11 Explain what is a reflection in Java? Give an
example of functionality that can be only implemented
through Java reflection.
Q-12 How can you swap two numbers without using the
third variable in Java?
Q-13 Write a program in Java to find if a number is
prime or not.
Q-14 Write a Java program to calculate the square root
of a number.
Q-15 Write a program in Java to implement the insertion
sort algorithm.

8. Q-16 Comment on method overriding and method
overloading by giving a relevant example.
Q-17 Write a Java program to implement an iterative
quicksort sorting algorithm.
Q-18 Write a Java program to implement a merge sort
algorithm.
Q-19 Write a Java Comparator to compare two
employees based on their names, age, and
departments?
Q-20 Write a Java program to check whether a number
is Armstrong or not.

9. These were some commonly asked Java
coding interview questions that you can
practice. It can help you clear a
programming interview and strengthen
your coding skills. You may also consider
taking professional-led Java training to
acquire the necessary coding expertise
and prepare for technical interviews.