QBurst Technologies Android Developer Interview Questions and Answers

Round duration - 60 minutes
Round difficulty - Medium

The interviewer was really cool. He realized that I mostly work on java applications so he chose to ask me stuff related to that. He didn't want me to know the answer well but just wanted me to approach to it, maybe think more. He went through my resume back and forth and asked mostly about all my projects and their logic and how could I take them to the next level.
Tips: Be confident. Its okay not to know any answer, just try giving it a shot in the approach.

Q1. What is the difference between an abstract class and an interface in Java?
Ans. 
Abstract class can have both abstract and non-abstract methods, while interface can only have abstract methods.
• Abstract class can have constructors, member variables, and methods with implementation.

• Interface can only have abstract methods and constants.

• A class can implement multiple interfaces but can only extend one abstract class.

• Example: Abstract class - Animal with abstract method 'eat', Interface - Flyable with m
Answered by AI
Add your answer
Q2. What is the difference between 'final', 'finally', and 'finalize' in Java?
Ans. 
final is a keyword used to declare constants, finally is a block used in exception handling, and finalize is a method used for cleanup.
• final is a keyword used to declare constants in Java, meaning the value cannot be changed once assigned. Example: final int x = 10;

• finally is a block used in exception handling to ensure a piece of code is always executed, whether an exception is thrown or not. Example: try { // code } ...read more
Answered by AI
Add your answer
Q3. What is the difference between the private and final access modifiers in Java?
Ans. 
Private restricts access to the class itself, while final prevents inheritance and method overriding.
• Private access modifier restricts access to the class itself, while final access modifier prevents inheritance and method overriding.

• Private members are only accessible within the same class, while final classes cannot be extended and final methods cannot be overridden.

• Example: private int num; - num can only be accesse...read more
Answered by AI
Add your answer
Q4. What are the steps for establishing a JDBC connection?
Ans. 
Establishing a JDBC connection involves loading the driver, creating a connection, creating a statement, executing queries, and handling exceptions.
• Load the JDBC driver using Class.forName() method

• Create a connection using DriverManager.getConnection() method

• Create a statement using connection.createStatement() method

• Execute queries using statement.executeQuery() method

• Handle exceptions using try-catch blocks
Answered by AI
Add your answer
Q5. What is JSON?
Ans. 
JSON is a lightweight data interchange format used to store and transmit data between a server and a web application.
• JSON stands for JavaScript Object Notation.

• It is easy for humans to read and write, and easy for machines to parse and generate.

• JSON is language-independent and can be used with any programming language.

• Example: {"name": "John", "age": 30}

• Example: [{"name": "Alice", "age": 25}, {"name": "Bob", "age": 35}
Answered by AI
Add your answer
Q6. What do you know about garbage collection in Java?
Ans. 
Garbage collection in Java is the process of automatically managing memory by deallocating objects that are no longer needed.
• Garbage collection helps in preventing memory leaks by reclaiming memory used by objects that are no longer referenced.

• Java uses a garbage collector to automatically manage memory, unlike languages like C++ where memory management is manual.

• Garbage collection in Java can be triggered by calling S...read more
Answered by AI
Add your answer

Round duration - 30 minutes
Round difficulty - Easy

I wouldn't say it went great but it was fine. I did not think I would clear it as for most of the questions the interviewer seemed disappointed and wanted more out of me.

Round duration - 90 Minutes
Round difficulty - Medium

It was an online technical round. There were around 20 MCQs and two coding questions. The round had an login window of 30 minutes. One coding question was of the level leetcode medium and the other was leetcode hard.

Q1. 
Search in a Row-wise and Column-wise Sorted Matrix Problem Statement
You are given an N * N matrix of integers where each row and each column is sorted in increasing order. Your task is to find the positi...read more
Ans. 
Given a sorted N * N matrix, find the position of a target integer X.
• Iterate over each row and column to search for the target integer

• Utilize the sorted nature of the matrix to optimize the search process

• Return the position of the target integer if found, else return -1 -1
Answered by AI
Add your answer
Q2. 
Euler’s Totient Function Problem Statement
Given an integer N, your task is to determine the count of integers between 1 and N (inclusive) that are coprime to N.
Input:
The first line contains an intege...read more
Ans. 
Euler's Totient Function calculates count of integers coprime to N between 1 and N.
• Implement Euler's Totient Function to calculate count of coprime integers to N.

• Use the formula: phi(N) = N * (1 - 1/p1) * (1 - 1/p2) * ... * (1 - 1/pk) where p1, p2, ..., pk are prime factors of N.

• Example: For N = 9, phi(9) = 9 * (1 - 1/3) = 6.
Answered by AI
Add your answer

Round duration - 60 Minutes
Round difficulty - Medium

It was a technical + HR round. The interview panel consisted of two technical guys and one person from HR.

Q1. 
Sort Array of Strings Problem Statement
Given an array of strings ARRSTR[] of size N, and a character C, your task is to sort the ARRSTR[] array according to a new alphabetical order that starts with the ...read more
Ans. 
Sort an array of strings based on a new alphabetical order starting with a given character.
• Iterate through the array of strings and compare each string with the given character to determine the new order.

• Implement a custom comparator function to sort the strings based on the new alphabetical order.

• Use built-in sorting functions in programming languages like Python, Java, or C++ to efficiently sort the array.
Answered by AI
Add your answer
Q2. Can you explain the pillars of Object-Oriented Programming (OOP)?
Ans. 
The pillars of OOP are Inheritance, Encapsulation, Abstraction, and Polymorphism.
• Inheritance allows a class to inherit properties and behavior from another class.

• Encapsulation restricts access to certain components of an object, protecting its integrity.

• Abstraction hides complex implementation details and only shows the necessary features.

• Polymorphism allows objects to be treated as instances of their parent class, ena
Answered by AI
Add your answer