Java Coding Interview Questions You Must Learn

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Java Coding Interview Questions You Must Learn
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Technical job interviews are the hardest to crack
as recruiters testa candidates 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
learners todevote adequate time to writing
programs, practicing codes, testing, and
debugging errors.
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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.
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Top 20 Java Coding Interview Questions You Must
Learn
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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?
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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.
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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.
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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.
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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.