Enterprise JavaBeans (EJB) has long been a core part of the Java EE (Jakarta EE) ecosystem. Although newer technologies like Spring have taken the spotlight in recent years, many enterprise applications still use EJB for building scalable, distributed, and secure applications.
If you’re preparing for a Java EE interview in 2025, brushing up on EJB Enterprise JavaBeans interview questions is essential.
In this guide, we’ll cover:
- Core EJB concepts
- Frequently asked EJB interview questions
- Real-world use cases
- Tips to answer confidently
Whether you’re a fresher or an experienced Java developer, this list will help you prepare for your next big opportunity.
🌟 What is EJB (Enterprise JavaBeans)?
Enterprise JavaBeans (EJB) is a server-side software component that encapsulates business logic of an application. It is part of the Java EE platform and enables the development of modular, distributed, and transactional applications.
EJB simplifies development by handling concerns like:
- Transactions
- Security
- Concurrency
- Remote access
🔑 EJB Interview Questions with Answers
1. What are the types of EJBs?
Answer:
There are three types of EJBs:
- Session Beans: Handle business logic. Types include:
- Stateless
- Stateful
- Singleton
- Message-Driven Beans (MDBs): Handle asynchronous messaging.
- Entity Beans (deprecated in EJB 3.0): Used for persistence, now replaced by JPA.
2. Difference between Stateless and Stateful Session Beans?
| Feature | Stateless Bean | Stateful Bean |
|---|---|---|
| State | Doesn’t maintain client state | Maintains client state |
| Scalability | More scalable | Less scalable |
| Use Case | Reusable services | Session-specific interactions |