JavaServer Faces (JSF) remains a key component of enterprise Java applications. Although modern front-end frameworks like Angular or React are often preferred for UI development, JSF continues to be widely used in legacy systems and enterprise Java EE applications due to its server-side component-based architecture.
If you’re preparing for a Java-related job interview—especially in companies that work on legacy platforms—JSF interview questions are likely to come up. This guide covers core JSF concepts, technical interview questions, and best-practice answers for both freshers and experienced professionals.
Let’s dive in and prepare you for success!
🚀 What is JSF?
JSF (JavaServer Faces) is a Java-based web application framework developed by Oracle. It simplifies the development of user interfaces for server-side applications by using reusable UI components and a robust lifecycle.
✅ Benefits of Using JSF
Here are some of the main reasons why JSF is still in use in enterprise applications:
- Component-Based Architecture: Allows reusability of UI components.
- MVC Design Pattern: Follows the Model-View-Controller pattern for separation of concerns.
- Tight Integration with Java EE: Works seamlessly with EJB, CDI, and JPA.
- Built-In Navigation: Provides simplified page navigation and URL mapping.
- Rich UI Support: Easily integrates with component libraries like PrimeFaces and RichFaces.
- Validation & Conversion: Offers built-in support for input validation and type conversion.
- Tooling Support: Supported by major IDEs like Eclipse, IntelliJ IDEA, and NetBeans.
📘 JSF Interview Questions for Freshers
1. What is JSF and how is it different from JSP?
JSF is a component-based UI framework, while JSP (JavaServer Pages) is a page-centric technology. JSF uses reusable UI components and a structured lifecycle; JSP is more like scripting inside HTML.
2. Explain the JSF lifecycle.
The JSF lifecycle has six phases:
- Restore View
- Apply Request Values
- Process Validations
- Update Model Values
- Invoke Application
- Render Response
3. What is a managed bean in JSF?
A managed bean is a Java class registered with the JSF framework using annotations like @ManagedBean or via faces-config.xml. It holds UI logic and is used to handle user input and interface behavior.
4. What is a backing bean?
A backing bean is a type of managed bean that directly backs a JSF UI component, typically controlling the business logic and interactions.
5. How do you configure a JSF application?
Configuration is typically done in web.xml and via annotations such as @FacesServlet. Starting from JSF 2.0, annotations can reduce the need for XML configuration.
6. What are facelets in JSF?
Facelets is the view declaration language for JSF. It replaces JSP in newer versions of JSF, offering better templating and component integration.
💼 JSF Interview Questions for Experienced Developers
7. What is the difference between @ManagedBean and @Named in JSF?
@ManagedBean is specific to JSF, while @Named is a CDI (Contexts and Dependency Injection) annotation, providing more flexibility and better integration with Java EE technologies.
8. What is the purpose of faces-config.xml?
faces-config.xml is the configuration file used to define managed beans, navigation rules, converters, validators, and lifecycle hooks for JSF.
9. How does JSF handle validation and conversion?
JSF provides built-in converters and validators, such as f:convertDateTime, f:validateLength, or you can create custom ones by implementing Converter or Validator interfaces.
10. How is navigation handled in JSF?
Navigation is defined in faces-config.xml or using implicit navigation where method outcomes match view names. You can also use navigation-rule and navigation-case for complex flows.
11. What is ViewScoped in JSF?
@ViewScoped keeps a bean alive as long as the user is interacting with the same JSF view (i.e., until navigation to another page occurs). Useful for Ajax-driven UIs.
12. How does Ajax work in JSF?
JSF provides the f:ajax tag to perform partial page updates without full reloads. This enables responsive interfaces similar to modern web apps.
xmlCopyEdit<h:inputText value="#{user.name}">
<f:ajax event="keyup" render="output"/>
</h:inputText>
<h:outputText id="output" value="#{user.name}"/>
13. What are composite components in JSF?
Composite components are reusable UI components built using other JSF components. They promote modular UI development and are defined using <composite:interface> and <composite:implementation>.
14. How do you handle exceptions in JSF?
You can use web.xml error-page configuration, or implement ExceptionHandler or ExceptionHandlerFactory for custom global error handling.
15. How does JSF integrate with Spring?
You can integrate JSF with Spring by using @Component or @Service with Spring’s @Autowired annotations, and referencing these beans in JSF via EL expressions.
🧠 Advanced JSF Interview Topics
- JSF with PrimeFaces: PrimeFaces is a rich UI component library that enhances JSF’s capabilities. Know how to use data tables, dialogs, charts, etc.
- Custom Components: Create reusable components by defining tags and behaviors.
- Security in JSF: Use JAAS or integrate with Spring Security for role-based access control.
- Performance Optimization: Minimize view scope, reduce session size, and avoid excessive server-side rendering.
⚡ JSF vs Other Frameworks
| Feature | JSF | Spring MVC | Angular / React |
|---|---|---|---|
| Language | Java (Server-side) | Java (Server-side) | JavaScript (Client-side) |
| Architecture | Component-based | Annotation-driven | Component-based |
| UI Interaction | Server-side | Server-side | Client-side |
| Use Case | Enterprise Java apps | RESTful apps | Modern SPAs |
JSF is best for legacy and enterprise apps needing server-rendered UIs.
📌 JSF Tips for Interview Success
- Understand JSF’s role in modern Java EE applications.
- Be clear on the JSF lifecycle and managed beans scope (
@RequestScoped,@SessionScoped, etc.). - Get hands-on with a small JSF + PrimeFaces project.
- Know how to integrate JSF with EJB or JPA.
🙋♂️ JSF Interview Questions: FAQ
Q1: Is JSF still used in 2025?
Yes, especially in enterprise and legacy systems. While not as trendy as React or Angular, JSF still powers many mission-critical Java EE applications.
Q2: Which JSF component library is best?
PrimeFaces is the most popular and actively maintained JSF component library, offering a wide variety of modern UI elements.
Q3: Is JSF better than JSP?
Yes. JSF offers a more structured, component-based approach with support for AJAX, validation, and built-in navigation, making it superior for complex UIs.
📝 Final Thoughts
JavaServer Faces may not be the flashiest framework on the market, but its deep integration with Java EE and enterprise stability make it a key technology in many large-scale systems. By preparing with these JSF interview questions, you’ll be ready to tackle interviews with confidence—whether you’re a beginner or a seasoned developer.
Understanding JSF’s lifecycle, annotations, managed beans, and how it compares with other frameworks will give you a competitive edge in today’s Java job market.