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NullClass Fullstack Java Developer Interview Questions and Answers

Updated 23 Apr 2024

NullClass Fullstack Java Developer Interview Experiences

1 interview found

Interview experience
4
Good
Difficulty level
-
Process Duration
-
Result
-
Round 1 - Group Discussion 

They asked questions about my project.

Round 2 - Coding Test 

All coding questions are based on Data Structures and Algorithm

Round 3 - HR 

(2 Questions)

  • Q1. HR round is one of the friendly round.
  • Q2. 1.Introduce yourself 2.Why should we hire you?

Interview Preparation Tips

Interview preparation tips for other job seekers - One of the important advice i would like to give you is be confident while giving interview.

Interview questions from similar companies

Interview experience
4
Good
Difficulty level
Moderate
Process Duration
4-6 weeks
Result
-

I applied via Recruitment Consulltant and was interviewed in Sep 2024. There were 2 interview rounds.

Round 1 - Technical 

(3 Questions)

  • Q1. Find the second largest element from array
  • Ans. 

    Find the second largest element from array of strings

    • Sort the array in descending order

    • Access the element at index 1 to get the second largest element

  • Answered by AI
  • Q2. Java basics and advanced programming
  • Q3. Failsafe vs fail fast integrators
  • Ans. 

    Failsafe integrators prioritize system stability by handling errors gracefully, while fail fast integrators prioritize quick detection and resolution of errors.

    • Failsafe integrators focus on ensuring the system continues to function even in the presence of errors.

    • Fail fast integrators aim to quickly identify and address errors to prevent further issues.

    • Failsafe integrators often use techniques like retries, circuit brea...

  • Answered by AI
Round 2 - Technical 

(2 Questions)

  • Q1. Saga design patterns
  • Q2. Micro services architecture

Skills evaluated in this interview

Interview experience
3
Average
Difficulty level
Moderate
Process Duration
Less than 2 weeks
Result
Selected Selected

I applied via Naukri.com and was interviewed in Oct 2024. There was 1 interview round.

Round 1 - Technical 

(2 Questions)

  • Q1. Difference between jvm jre jdk?
  • Ans. 

    JVM is the virtual machine that runs Java bytecode, JRE is the runtime environment for Java programs, and JDK is the development kit for creating Java applications.

    • JVM (Java Virtual Machine) is responsible for running Java bytecode on different platforms.

    • JRE (Java Runtime Environment) includes JVM, libraries, and other components necessary to run Java applications.

    • JDK (Java Development Kit) is a software development ki...

  • Answered by AI
  • Q2. Why string is immutable?
  • Ans. 

    String is immutable in Java to ensure security, thread safety, and optimization.

    • Immutable strings prevent accidental changes to sensitive data like passwords.

    • Immutable strings allow for safe sharing of string literals across multiple threads.

    • Immutable strings enable string pooling for memory optimization.

    • Example: String str = "Hello"; str.concat(" World"); // str remains "Hello"

  • Answered by AI

Skills evaluated in this interview

Interview experience
4
Good
Difficulty level
Moderate
Process Duration
Less than 2 weeks
Result
-

I applied via Naukri.com and was interviewed in Apr 2024. There were 3 interview rounds.

Round 1 - Technical 

(2 Questions)

  • Q1. Tell me about internal working of JVM
  • Q2. Tell me about SAGA pattern in Microservices
  • Ans. 

    SAGA pattern is a design pattern used in microservices architecture to manage distributed transactions.

    • SAGA pattern breaks down a long-running transaction into a series of smaller, independent transactions.

    • Each step in the SAGA pattern is a separate service that communicates with other services through events.

    • If a step fails, compensating transactions are executed to rollback the changes made by previous steps.

    • Example:...

  • Answered by AI
Round 2 - Technical 

(2 Questions)

  • Q1. Tell me about your current project structure
  • Q2. What is an API , how would you secure an API
  • Ans. 

    API stands for Application Programming Interface. It defines the methods and data formats that applications can use to communicate with each other.

    • API is a set of rules and protocols that allows different software applications to communicate with each other.

    • To secure an API, you can use authentication methods like OAuth, API keys, or JWT tokens.

    • Implementing encryption (HTTPS) and rate limiting can also enhance API secu...

  • Answered by AI
Round 3 - HR 

(2 Questions)

  • Q1. Why do you want to relocate to Bangalore
  • Q2. Tell me about one instance where you faced pressure and how did you overcome ?

Interview Preparation Tips

Interview preparation tips for other job seekers - You can assume easy to medium level questions.
Interview experience
1
Bad
Difficulty level
-
Process Duration
-
Result
-
Round 1 - Technical 

(1 Question)

  • Q1. Basic js question on hoisting, closure, promises
Round 2 - Behavioral 

(1 Question)

  • Q1. Basic resume based
Round 3 - HR 

(1 Question)

  • Q1. Salary discussion -- HR never responded
Interview experience
4
Good
Difficulty level
-
Process Duration
-
Result
-
Round 1 - One-on-one 

(4 Questions)

  • Q1. Java Basic questions
  • Q2. SpringBoot Basic questions
  • Q3. Simple DSA problem: "introduction" find duplicate characters
  • Ans. 

    Find duplicate characters in a given array of strings

    • Iterate through each string in the array

    • For each string, iterate through each character and store the count in a hashmap

    • If the count of any character is greater than 1, it is a duplicate

  • Answered by AI
  • Q4. Write code for REST API using spring boot, include all annotation
  • Ans. 

    Code for REST API using Spring Boot with annotations

    • Use @RestController annotation to define the class as a REST controller

    • Use @RequestMapping annotation to map HTTP requests to handler methods

    • Use @GetMapping, @PostMapping, @PutMapping, @DeleteMapping annotations for specific HTTP methods

    • Use @PathVariable annotation to extract values from the URI

    • Use @RequestBody annotation to bind HTTP request body to a method paramete

  • Answered by AI

Skills evaluated in this interview

Interview experience
3
Average
Difficulty level
Hard
Process Duration
More than 8 weeks
Result
No response

I applied via Company Website and was interviewed in Mar 2024. There were 3 interview rounds.

Round 1 - HR 

(3 Questions)

  • Q1. Tell me about yourself?
  • Ans. •I'm Akashdeep Prasad. • I'm in my early twenties. • I'm born and brought up in Mumbai, Andheri but currently I'm reside in Thane. - Now, coming to my highest qualification :- • I have completed my graduation in Bachelor of Science in Information Technology from University of Mumbai. - I like to share my certification with you :- • I'm certified Java Full Stack Developer. - Sir, I like to share my hobbies with you :...
  • Answered Anonymously
  • Q2. Why should I hire you ?
  • Q3. What is your salary expectation?
Round 2 - Technical 

(1 Question)

  • Q1. I forgot question
Round 3 - Technical 

(1 Question)

  • Q1. I can't remember what questions asked

Interview Preparation Tips

Topics to prepare for TCS Fullstack Java Developer interview:
  • Java
Interview preparation tips for other job seekers - The job seekers is good and friendly.
Interview experience
1
Bad
Difficulty level
-
Process Duration
-
Result
No response

I applied via Naukri.com and was interviewed in May 2024. There was 1 interview round.

Round 1 - Technical 

(1 Question)

  • Q1. Tech panel did not show up

Interview Preparation Tips

Interview preparation tips for other job seekers - Very Bad Process. They kept rescheduling the interview call.
First they scheduled the Technical interview. Sent the invites & then when I joined at the particular time - HR came on the call instead of tech panel & told that interviewer is busy ,got some other interview going on. So, cant have it right now.
This kind of thing happened 3 times where none of tech panel show up.
Very bad. Not expecting from such a big company like Wipro.

Afterwards, they dont even pick call. They just call randomly & setup an interview. And then cancel it. Very unprofessional.
Interview experience
1
Bad
Difficulty level
Easy
Process Duration
2-4 weeks
Result
Not Selected

I was interviewed in Aug 2023.

Round 1 - Resume Shortlist 
Pro Tip by AmbitionBox:
Keep your resume crisp and to the point. A recruiter looks at your resume for an average of 6 seconds, make sure to leave the best impression.
View all tips
Round 2 - Technical 

(4 Questions)

  • Q1. SQL - a table with emp-id, emp-name, manager-id, Need to find the manger name for each emplyee.
  • Q2. FizzBuzz - if number is divisible by 3 print "fizz", if by 5 print "buzz", if by both "fizzbuzz"
  • Ans. 

    A simple program to print 'fizz' for multiples of 3, 'buzz' for multiples of 5, and 'fizzbuzz' for multiples of both.

    • Iterate through numbers from 1 to n.

    • Use modulo operator to check divisibility by 3 and 5.

    • Print 'fizz', 'buzz', or 'fizzbuzz' accordingly.

  • Answered by AI
  • Q3. Is it necessary for classes implementing an interface to implement interface methods?
  • Ans. 

    Yes, classes implementing an interface must implement interface methods.

    • Classes implementing an interface must provide concrete implementations for all methods declared in the interface.

    • Failure to implement all interface methods will result in a compilation error.

    • Interfaces are used to define a contract that implementing classes must adhere to.

  • Answered by AI
  • Q4. Spring basics - annotations
Round 3 - Technical 

(1 Question)

  • Q1. Spring boot basics
Round 4 - HR 

(1 Question)

  • Q1. Talked about my previous companies and salary. Before they conduct the interview I had told them my expectation, while negotiation they denied for providing that and were offering just 10% hike over my cur...

Interview Preparation Tips

Interview preparation tips for other job seekers - Don't go for this company. It is just waste of time.

Skills evaluated in this interview

Interview experience
4
Good
Difficulty level
-
Process Duration
-
Result
-
Round 1 - Resume Shortlist 
Pro Tip by AmbitionBox:
Don’t add your photo or details such as gender, age, and address in your resume. These details do not add any value.
View all tips
Round 2 - Coding Test 

(9 Questions)

  • Q1. What is sychronization ?
  • Ans. 

    Synchronization is the process of coordinating multiple threads to ensure safe and consistent access to shared resources.

    • Synchronization is used to prevent race conditions and ensure thread safety.

    • It can be achieved using synchronized blocks or methods.

    • Synchronization can cause performance issues if not used properly.

    • Example: Synchronizing access to a shared counter variable in a multi-threaded application.

  • Answered by AI
  • Q2. What is encapsulation ?
  • Ans. 

    Encapsulation is the process of hiding implementation details and providing access to only necessary information.

    • Encapsulation is achieved through access modifiers such as public, private, and protected.

    • It helps in achieving data abstraction and information hiding.

    • Encapsulation provides better control over the data and prevents unauthorized access.

    • Example: A class with private variables and public methods to access the...

  • Answered by AI
  • Q3. What is interface in java ?
  • Ans. 

    An interface in Java is a collection of abstract methods and constants that can be implemented by a class.

    • Interfaces are used to achieve abstraction and provide a way to implement multiple inheritance in Java.

    • All methods in an interface are abstract by default and cannot have a body.

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

    • Interfaces can also have default and static methods with a body.

    • Ex...

  • Answered by AI
  • Q4. What is collection framework?
  • Ans. 

    Collection framework is a set of classes and interfaces that provide a way to store and manipulate groups of objects.

    • It provides interfaces like List, Set, Queue, etc. for storing collections of objects.

    • It also provides classes like ArrayList, HashSet, PriorityQueue, etc. that implement these interfaces.

    • It allows easy manipulation of collections using methods like add, remove, contains, etc.

    • It provides algorithms like ...

  • Answered by AI
  • Q5. What is diffrence between Arraylist and vector ?
  • Ans. 

    ArrayList is not synchronized while Vector is synchronized.

    • ArrayList is faster than Vector as it is not synchronized.

    • Vector is thread-safe while ArrayList is not.

    • Vector is a legacy class while ArrayList is not.

    • Vector can grow by a specified amount while ArrayList grows by 50% of its size.

    • Example: ArrayList list = new ArrayList<>(); Vector vector = new Vector<>();

    • Example: list.add(1); vector.add(1);

    • Example: list.get(0);

  • Answered by AI
  • Q6. What are the legacy classes in java?
  • Ans. 

    Legacy classes in Java are the classes that have been replaced by newer versions but are still supported for backward compatibility.

    • Legacy classes are part of the Java API and are still supported for backward compatibility.

    • They have been replaced by newer versions but are still used in older applications.

    • Examples of legacy classes include Vector, Hashtable, and Enumeration.

    • Legacy classes are not recommended for use in ...

  • Answered by AI
  • Q7. What is joins in SQL ?
  • Ans. 

    Joins in SQL are used to combine data from two or more tables based on a related column.

    • Joins are used to retrieve data from multiple tables in a single query.

    • There are different types of joins such as inner join, left join, right join, and full outer join.

    • Inner join returns only the matching rows from both tables, left join returns all rows from the left table and matching rows from the right table, right join returns...

  • Answered by AI
  • Q8. What is autoboxing and auto-unboxing ?
  • Ans. 

    Autoboxing is the automatic conversion of primitive data types to their corresponding object wrapper classes.

    • Autoboxing allows primitive data types to be used as objects.

    • Auto-unboxing is the reverse process of autoboxing.

    • Autoboxing and auto-unboxing are performed automatically by the compiler.

    • Example: int i = 10; Integer j = i; // autoboxing

    • Example: Integer j = 10; int i = j; // auto-unboxing

  • Answered by AI
  • Q9. Difference between where clause and having clause in SQL ?
  • Ans. 

    Where clause filters rows before grouping, having clause filters groups after grouping.

    • Where clause is used to filter rows based on a condition before grouping.

    • Having clause is used to filter groups based on a condition after grouping.

    • Where clause is used with SELECT, UPDATE, DELETE statements.

    • Having clause is used with SELECT statement and GROUP BY clause.

    • Where clause cannot contain aggregate functions.

    • Having clause c...

  • Answered by AI

Skills evaluated in this interview

NullClass Interview FAQs

How many rounds are there in NullClass Fullstack Java Developer interview?
NullClass interview process usually has 3 rounds. The most common rounds in the NullClass interview process are Group Discussion, Coding Test and HR.

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