General

Introduction In Java, both HashMap and ConcurrentHashMap are used to store key-value pairs, but they differ mainly in thread-safety and performance in multi-threaded environments. 1. What is HashMap? Map<String, Integer> map = new HashMap<>();map.put(“A”, 1);map.put(null, 2); // Allowed 2. What is ConcurrentHashMap? ConcurrentHashMap<String, Integer> map = new ConcurrentHashMap<>();map.put(“A”, 1);// map.put(null, 2); // Throws NullPointerException 3. … Read more

1. What is Spring Security? Answer: Spring Security is a powerful and customizable framework for authentication, authorization, and access control in Java applications. It integrates seamlessly with the Spring Framework to secure web applications, REST APIs, and method-level access. 2. What are the key features of Spring Security? Answer: 3. How does Spring Security handle … Read more

PART 1: Spring Boot – Core + Project Based Questions 1. What is Spring Boot and why did you use it? Answer:Spring Boot is an extension of the Spring Framework that simplifies application development by providing: In my project:I used Spring Boot to build a REST-based microservice where quick setup, minimal configuration, and easy deployment … Read more