TCS Java Developer Interview Questions, Process, and Tips

HashMap works internally using an array of buckets to store key-value pairs, with each bucket containing a linked list of entries.

• HashMap uses hashing to determine the index of the bucket where the key-value pair should be stored.

• If multiple key-value pairs hash to the same index, they are stored in a linked list within that bucket.

• When retrieving a value, the key's hash code is used to find the correct bucket, then th...read more

application.properties is used to store configuration settings for Java applications.

• Centralized storage for configuration settings

• Easy to update without changing code

• Allows for different configurations for different environments (development, testing, production)

• Can be used to store database connection details, API keys, logging settings, etc.

Abstract class can have both abstract and non-abstract methods, while interface can only have abstract methods.

• Abstract class can have constructors, fields, and methods, while interface cannot have any of these.

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

• Abstract classes are used to define common behavior among subclasses, while interfaces are used to define a contract for classes ...read more

The main difference between PUT and PATCH methods in Spring Boot is the level of data that is updated.

• PUT method is used to update an entire resource, while PATCH method is used to update only specific fields of a resource.

• PUT method requires the client to send the entire updated resource, while PATCH method only requires the client to send the specific fields that need to be updated.

• PUT method is idempotent, meaning m...read more

Developed a web-based inventory management system for a retail company

• Used Java, Spring Boot, and MySQL for backend development

• Implemented user authentication and authorization using Spring Security

• Designed a responsive front-end using HTML, CSS, and JavaScript

HashMap is a data structure that stores key-value pairs and uses hashing to efficiently retrieve values.

• HashMap uses hashing to store and retrieve key-value pairs.

• It allows null keys and values.

• HashMap does not maintain insertion order.

• Example: HashMap map = new HashMap<>();

Spring is a framework for building Java applications, while Spring Boot is a tool for quickly creating standalone Spring-based applications.

• Spring is a comprehensive framework that provides support for various functionalities like dependency injection, aspect-oriented programming, and more.

• Spring Boot is an opinionated tool that simplifies the setup and configuration of Spring applications, allowing developers to quick...read more

Java is a high-level programming language known for its portability, security, and versatility.

• Java is an object-oriented language, meaning it focuses on creating objects that interact with each other.

• It is platform-independent, meaning Java programs can run on any device that has a Java Virtual Machine (JVM).

• Java is known for its security features, such as automatic memory management and built-in exception handling.

• Po...read more

Spring Boot is a framework that simplifies the development of Java applications by providing pre-configured settings and tools.

• Spring Boot eliminates the need for manual configuration by providing defaults for most settings.

• It allows for standalone Spring applications that can be started with a simple 'java -jar' command.

• Spring Boot includes embedded servers like Tomcat, Jetty, or Undertow for deploying web application...read more