Infosys Interview Questions Asked in Real Interviews

Questions:

1. 1.1. What is the difference between HashMap and ConcurrentHashMap? 2. Can you explain how HashMap works internally in Java? 3. What is the difference between Comparable and Comparator interfaces? 4. What is the Java 8 Stream API? Can you give a real-time example of how it is used? 5. What is the difference between Checked Exceptions and Unchecked Exceptions? 6. What is the difference between Method Overloading and Method Overriding? 7. Can you explain the lifecycle of a thread in Java multithreading? 8. What is ExecutorService and why is it used? 9. What is a Deadlock in Java, and how can it be prevented? 10. What is the difference between final, finally, and finalize?

Questions:

1. 1.1.Explain the difference between JDK, JRE, and JVM. How are they related? 2.What is the difference between String, StringBuilder, and StringBuffer? When would you use each? 3.How do you implement custom validation in Spring Boot? Explain with an example. 4.Write a program to check if a string is a palindrome without using built-in reverse functions. 5.What is the difference between @RestController and @Controller in Spring? 6.Explain the Java Memory Model. 7.What are heap and stack? How does garbage collection work? 8.How do you connect to a MySQL database in Spring Boot? Explain the configuration. 9.Design a library management system. Include entities, relationships, and key operations. 10.What are the different types of joins in SQL? Explain with examples. 11.Explain your experience with version control (Git). How do you handle merge conflicts?

Questions:

1. 1.What are the important features of Java 17? What is JWT? How does JWT work in a real-time application? How is authentication handled in microservices? What is microservices architecture? How do microservices communicate with each other? How does Kafka integrate with a Spring Boot application? Difference between synchronous and asynchronous communication How do you handle data consistency across microservices? What happens if one service goes down? What are the advantages and disadvantages of stored procedures? What are Azure Functions? Why do we use serverless architecture? Write a program to print non-repeated characters in a string Why do we use stored procedures? How do you handle failures in Kafka-based systems?