IMCS Group. Java Developer Intern Interview Questions and Answers

Q1. Internal working of HashMap
Add your answer
Q2. Features of java8
Add your answer
Q3. Use of synchronized keyword
Add your answer
Q4. Difference between failsafe and fail fast and also its implementation
Add your answer
Q5. Coding question : sort an array, use of streams to find names from employee object whose salary is greater than 50000
Add your answer
Q6. Difference between concurrent and generic collection
Add your answer
Q7. What is string pool. What is string literal?
Add your answer
Q8. Security measures used in your project
Add your answer
Q9. What is difference between rest and soap
Add your answer
Q10. What do u mean by REST state
Add your answer
Q11. What is serialization? What is the way to stop serialization?
Add your answer

Q1. Difference between failsafe and faifast
Add your answer
Q2. Difference between concurrent and generic collection
Add your answer
Q3. Security measures used in current project
Add your answer
Q4. Why you are leaving your current organization and follow up questions on that
Add your answer

It's walkin, so they conducted 1 technical mcqs round.

Q1. Multi threading
Add your answer
Q2. Internal working of hashmap
Ans. 
HashMap in Java is a data structure that stores key-value pairs and uses hashing to efficiently retrieve values based on keys.
• HashMap uses an array of buckets to store key-value pairs.

• Keys are hashed to determine the index in the array where the key-value pair will be stored.

• In case of hash collisions, a linked list or a balanced tree is used to store multiple key-value pairs in the same bucket.

• HashMap allows null keys...read more
Answered by AI
Add your answer
Q3. Spring batch related
Add your answer
Q4. Non repeating characters in a array
Ans. 
Function to find and return all non-repeating characters in an array of strings.
• Iterate through the array and count the occurrences of each character using a HashMap.

• Then iterate through the array again and check if the count of each character is 1, if so add it to the result list.

• Return the list of non-repeating characters.
Answered by AI
Add your answer
Q5. 3rd highest salary
Ans. 
To find the 3rd highest salary in a database, we can use a SQL query with the 'LIMIT' and 'OFFSET' keywords.
• Use a SQL query with 'ORDER BY salary DESC' to sort the salaries in descending order.

• Use 'LIMIT 1 OFFSET 2' to skip the first two highest salaries and retrieve the third highest salary.

• Example: SELECT salary FROM employees ORDER BY salary DESC LIMIT 1 OFFSET 2;
Answered by AI
Add your answer
Q6. Qualifier vs primary
Ans. 
A qualifier in Java is used to specify additional information about a primary, which is the main data type or variable.
• A primary in Java is the main data type or variable, while a qualifier provides additional information about the primary.

• Qualifiers can be used to modify the behavior or characteristics of a primary.

• For example, in Java, 'final' is a qualifier that can be used to make a variable constant.
Answered by AI
Add your answer
Q7. Controller vs restcontroller
Ans. 
The main difference is that @RestController is a specialized version of @Controller that is used for RESTful web services.
• Both @Controller and @RestController are used in Spring MVC to handle HTTP requests, but @RestController is specifically used for RESTful web services.

• @Controller is used to create web pages, while @RestController is used to return data in JSON or XML format.

• @RestController is a convenience annotati...read more
Answered by AI
Add your answer
Q8. Spring boot annotataions
Add your answer
Q9. Oops concepts with examples
Ans. 
OOP concepts include inheritance, encapsulation, polymorphism, and abstraction.
• Inheritance: Allows a class to inherit properties and behavior from another class. Example: class Dog extends Animal.

• Encapsulation: Bundling data and methods that operate on the data into a single unit. Example: private variables with public getter and setter methods.

• Polymorphism: Ability for objects to be treated as instances of their paren...read more
Answered by AI
Add your answer
Q10. Spring batch configuration
Add your answer
Q11. They covered all java, spring and Microservices
Add your answer

Q1. Microservices architecture
Add your answer
Q2. How do Microservices communicate
Ans. 
Microservices communicate with each other through various communication protocols like HTTP, messaging queues, and gRPC.
• Microservices can communicate over HTTP using RESTful APIs.

• Messaging queues like RabbitMQ or Kafka can be used for asynchronous communication between microservices.

• gRPC is a high-performance, open-source RPC framework that can be used for communication between microservices.

• Service discovery mechanism...read more
Answered by AI
Add your answer
Q3. How to access the Microservice end point
Ans. 
Microservice endpoints can be accessed using HTTP requests with the appropriate URL
• Use HTTP methods like GET, POST, PUT, DELETE to interact with the microservice

• Construct the URL with the base URL of the microservice and the specific endpoint path

• Include any necessary headers or parameters in the request for authentication or data filtering
Answered by AI
Add your answer
Q4. Why we use microservices
Ans. 
Microservices allow for modular, scalable, and flexible software development by breaking down applications into smaller, independent services.
• Microservices enable easier maintenance and updates as each service can be developed, deployed, and scaled independently.

• They improve fault isolation, as failures in one service do not necessarily affect the entire application.

• Microservices promote agility and faster time-to-mark...read more
Answered by AI
Add your answer

Q1. Given an array {1, 2, 1, 4, 5, 4, 8, 7}, how can you use Streams to remove duplicates while retaining only the even numbers?
Ans. 
Use Streams to remove duplicates and retain only even numbers from an array.
• Convert the array to a stream using Arrays.stream()

• Use distinct() to remove duplicates

• Filter out odd numbers using filter()

• Collect the result using collect(Collectors.toList())
Answered by AI
Add your answer
Q2. What is the use of Static and final when you will use Static methods
Ans. 
Static methods can be accessed without creating an instance of the class, while final keyword makes the method unchangeable.
• Static methods belong to the class itself, not to any specific instance

• Final keyword ensures that the method cannot be overridden in subclasses

• Static methods are commonly used for utility methods that do not require access to instance variables

• Example: Math class in Java has static methods like Ma
Answered by AI
Add your answer
Q3. What is the difference between @restController and @controller Annotation
Ans. 
The @RestController annotation is used to define RESTful web services while @Controller annotation is used to define MVC controller.
• RestController is a specialized version of Controller used for RESTful web services

• RestController eliminates the need for @ResponseBody annotation

• Controller is used for traditional MVC controller functionality

• RestController returns data directly without needing to go through a view resolve...read more
Answered by AI
Add your answer
Q4. What is microservices why we use it
Ans. 
Microservices are a software development technique where applications are composed of small, independent services that communicate with each other.
• Microservices allow for easier scalability and maintenance of complex applications.

• Each service in a microservices architecture can be developed, deployed, and scaled independently.

• Microservices promote flexibility and agility in software development.

• Examples of companies us...read more
Answered by AI
Add your answer

Q1. Coding questions on java8
Add your answer
Q2. Regarding microservices
Add your answer
Q3. Internal working of circuit breaker
Ans. 
Circuit breaker is a design pattern used in software development to prevent system failures by temporarily stopping requests to a failing service.
• Circuit breaker monitors the number of failures and opens when a threshold is reached.

• When the circuit is open, requests are not sent to the failing service, preventing further failures.

• After a specified time, the circuit breaker closes and allows requests to be sent again.

• Ex...read more
Answered by AI
Add your answer
Q4. Frequency of occurrence of words
Ans. 
Frequency of occurrence of words in a given text can be calculated by counting each word and storing it in a data structure.
• Split the text into words using whitespace as delimiter

• Create a map to store word frequencies

• Iterate through the words and update the frequency count in the map

• Return the map with word frequencies
Answered by AI
Add your answer
Q5. How spring boot will work two databases
Ans. 
Spring Boot can work with two databases by configuring multiple data sources and using @Primary annotation.
• Configure multiple data sources in application.properties or application.yml

• Use @Primary annotation to specify the primary data source

• Use @Qualifier annotation to specify the secondary data source

• Example: @Configuration @EnableTransactionManagement public class DatabaseConfig { @Primary @Bean(name = "primaryDataSo...read more
Answered by AI
Add your answer

Q1. Explain architecture of your project
Add your answer
Q2. Some questions on Java, Spring Boot and sql
Add your answer

Q1. Project flow and some behavioural questions
Add your answer
Q2. Project contribution of yours
Ans. 
Developed a web application for tracking employee attendance and performance
• Implemented user authentication and authorization using Spring Security

• Utilized Hibernate for database interaction and data persistence

• Designed and developed RESTful APIs for frontend integration

• Used AngularJS for frontend development to create interactive user interfaces
Answered by AI
Add your answer

Q1. Basic formalities before offer release
Add your answer

The first round was an interview conducted with a GENAI virtual bot.

Q1. Internal architecture of Spring boot, how enable autoconfiguration works
Ans. 
Spring Boot uses autoconfiguration to automatically configure the Spring application based on dependencies and properties.
• Spring Boot autoconfiguration is achieved through @EnableAutoConfiguration annotation

• Autoconfiguration classes are located in the org.springframework.boot.autoconfigure package

• Autoconfiguration classes are conditionally applied based on the presence of specific classes or properties
Answered by AI
Add your answer
Q2. Questions mostly on microservices and coding question on restTemplate
Add your answer

Q1. Difference between hashmap and hash table
Ans. 
HashMap is non-synchronized and allows null values, while HashTable is synchronized and does not allow null values.
• HashMap is non-synchronized, meaning it is not thread-safe, while HashTable is synchronized and thread-safe.

• HashMap allows null values for both keys and values, while HashTable does not allow null keys or values.

• HashMap is generally preferred for non-thread-safe applications, while HashTable is used in mul
Answered by AI
Add your answer
Q2. Static block related questions
Add your answer
Q3. Arraylist and linkedlist question
Add your answer

Onlin test consist pf easy numerical questions

Easy questions not so difficult

Q1. Java oops concept
Add your answer
Q2. Basic sprophramming questions
Add your answer
Q3. Networking firewall cisco
Add your answer

Q1. Personal questions
Add your answer
Q2. Whetehr to willing to work in any locations
Ans. 
Yes, I am willing to work in any location for the right opportunity.
• I am open to relocating for the right job opportunity

• I am flexible and adaptable to new environments

• I believe working in different locations can provide valuable experiences and growth opportunities
Answered by AI
Add your answer