Java Professional Interview Guide

The productivity of developers has increased immensely because of AI. However, the interview process for hiring is still focused on the core concepts of the programming language. Java remains the leading enterprise technology globally, making modern programming skills essential for freshers. This book is your roadmap to understanding opportunities available, learning how to prepare, and knowing how to make an impact on the job market.

This new edition covers the concepts of Java architecture, OOPs, exception handling, and file handling, the IO package hierarchy, and the NIO package, along with concurrency, JDBC, and collections. Furthermore, this updated edition includes comprehensive interview questions with answers alongside major language updates from Java 9 to Java 25. It details advanced concepts like functional programming, design patterns, Spring Framework introduction, Hibernate, an introduction to monoliths and microservices, and API gateway setup.

By the end of this book, the readers will gain insight into the key concepts in recent versions of Java, followed by probable interview questions for the position of Java developer. After practicing these questions, the readers will be able to face the Java interviews with confidence and structured strategies.

What you will learn

● Maximize opportunities available within the tech market.

● Master compilation mechanics and the internal structure of Java.

● Implement modern features like updates from Java 9 to Java 25

● Build fast query architectures utilizing the collections hierarchy.

● Create flexible architectures implementing the Factory design pattern and Singleton pattern.

In this edition, you will learn how to:

● Language evolution features from modern updates from Java 9 to Java 25.

● Systematic interview strategies for distributed applications, including an introduction to Microservice patterns.

Who this book is for

This book is designed for both entry-level and experienced professionals preparing for Java developer interviews. While it offers a comprehensive overview of Java and J2EE concepts, a foundational understanding of core Java is recommended for effective learning.

Table of Contents

1. Preparation Beyond Technology

2. Architecture of Java

3. Object Orientation

4. Handling Exceptions

5. I/O and File Handling

6. Concurrency

7. Java Database Connectivity

8. Collections

9. Miscellaneous

10. Functional interfaces, Lambda expressions and streams

11. Design Patterns

12. Spring & Spring Boot

13. Hibernate

14. Microservices Architecture

Tejaswini Mandar Jog is an accomplished Java consultant and corporate trainer with nearly 15 years of experience in delivering advanced technical training. She specializes in Spring and Microservices architecture, with a strong focus on building scalable, resilient, and cloud-ready enterprise applications. Over the years, she has successfully trained a wide range of professionals, from fresh graduates to experienced engineers, enabling them to adapt to modern development practices and frameworks.She has extensive experience working with leading global organizations, including Wipro, Accenture, and Citibank, where she has delivered customized training programs tailored to real-world business needs. Her training approach emphasizes a balance between strong fundamentals and hands-on implementation, ensuring practical applicability in enterprise environments. Currently she is expanding her horizon in GenAI field, where she facilitates the team to upgrade themselves on the cutting-edge AI tools and adapt them in day-to-day work. In addition to her training contributions, Tejaswini is a prolific author and has written several well-regarded books, including "Learning Spring 5.0," "Reactive Programming with Java 9," "Java 9.0 to 17.0 Cookbook," and "Microservices with Spring Boot and Spring Cloud," among others. Her work reflects deep technical expertise and a commitment to simplifying complex concepts for learners and practitioners alike.

Mandar Maheshwar Jog is a seasoned Java trainer with over 15 years of experience in delivering high-quality technical training. His core expertise lies in Java and J2EE technologies, including Spring, Spring Boot, and Hibernate. He has consistently empowered both fresh graduates and experienced professionals with strong conceptual understanding and practical skills aligned with industry demands.In addition to his training engagements, Mandar is a freelance author and has authored the numerous books like "Java 9.0 to 13.0", "Microservices with Spring boot and Spring cloud", "Java 9.0 to 17.0 Cookbook". He also contributes as a technical reviewer for various Java-based books, ensuring accuracy, clarity, and industry relevance. Mandar actively participates as a key panellist in technical interview processes across multiple organizations, assessing candidates for both entry-level and experienced Java roles. Furthermore, he collaborates with academic institutions and organizations to design and enhance computer engineering curriculum ensuring alignment with evolving technology trends.