Advance java

1. What is Advanced Java?

Advanced Java refers to the programming concepts and technologies that extend the capabilities of Java, including web applications and enterprise applications.

2. What is a Servlet?

A Servlet is a Java class that handles HTTP requests and responses, allowing dynamic web content generation.

3. What is JSP?

JavaServer Pages (JSP) is a technology that enables the creation of dynamic web content using HTML and Java code.

4. What is JSF?

JavaServer Faces (JSF) is a Java specification for building component-based user interfaces for web applications.

5. What is EJB?

Enterprise JavaBeans (EJB) is a server-side software component that encapsulates business logic in enterprise applications.

6. What is Maven?

Maven is a build automation tool used primarily for Java projects, managing dependencies, builds, and project structure.

7. What is Spring Framework?

Spring is a comprehensive framework for building Java applications, providing features like dependency injection and aspect-oriented programming.

8. What is Hibernate?

Hibernate is an Object-Relational Mapping (ORM) framework that simplifies database interactions by mapping Java objects to database tables.

9. How does a Servlet work?

A Servlet processes requests from clients, performs business logic, and generates responses, typically in HTML format.

10. What is the Servlet lifecycle?

The Servlet lifecycle includes loading, instantiation, initialization, request handling, and destruction.

11. What is the difference between doGet() and doPost()

doGet() handles GET requests, typically for retrieving data, while doPost() handles POST requests, used for submitting data.

12. What is a Filter in Servlet?

A Filter is an object that performs filtering tasks on requests and responses in a web application.

13. What is a ServletContext?

ServletContext is an interface that provides information about the web application and allows communication between servlets.

14. What is the difference between JSP and Servlets?

JSP allows embedding Java code in HTML, while Servlets are Java classes that generate HTML dynamically.

15. What are JSP tags?

JSP tags are special elements in JSP pages used to perform specific tasks, like and .

16. What is a JSP Expression?

A JSP expression is used to output data onto a web page using the syntax <%= %>.

17. What is a JSP Directive?

A JSP directive provides global information about an entire JSP page, such as <%@ page %>.

18. What is a JSP Scriptlet?

A scriptlet is a piece of Java code embedded in JSP using <% %> tags.

19. What is an EL (Expression Language)?

EL is a simplified way to access data stored in JavaBeans and other objects in JSP pages.

20. What is the purpose of JSF?

JSF simplifies the development of user interfaces for Java web applications by providing reusable UI components.

21. What is a JSF managed bean?

A managed bean is a Java class that is managed by the JSF framework, used to handle UI components and business logic.

22. What is the role of FacesServlet?

FacesServlet processes all JSF requests and manages the lifecycle of JSF components.

23. What are JSF converters?

Converters are used to convert between the string representation of a data type and its object form in JSF.

24. What is a JSF lifecycle?

The JSF lifecycle consists of six phases: Restore View, Apply Request Values, Process Validations, Update Model Values, Invoke Application, and Render Response.

25. What are the types of EJB?

There are two main types: Stateless Session Beans and Stateful Session Beans, along with Message-Driven Beans.

26. What is a Stateless Session Bean?

A Stateless Session Bean does not maintain any state between method calls.

27. What is a Stateful Session Bean?

A Stateful Session Bean maintains state across multiple method calls from a client.

28. What is a Message-Driven Bean?

A Message-Driven Bean processes messages asynchronously from a messaging service.

29. What is JNDI?

Java Naming and Directory Interface (JNDI) is an API for accessing naming and directory services, used to look up EJBs.

30. What is a Maven POM file?

The POM (Project Object Model) file is an XML file that contains information about the project and configuration details for Maven.

31. What are Maven Dependencies?

Dependencies are external libraries that a project requires, defined in the POM file.

32. What is a Maven Repository?

A Maven Repository is a location where project artifacts are stored, including libraries and dependencies.

33. What is a Maven Plugin?

A Maven Plugin is a tool that adds specific functionalities to the Maven build process.

34. What is a Maven Build Lifecycle?

The Maven Build Lifecycle is a sequence of phases that define the steps in the build process, such as compile, test, and package.

35. What is dependency injection?

Dependency injection is a design pattern that allows an object to receive its dependencies from an external source rather than creating them internally.

36. What are Spring Beans?

Spring Beans are objects that are instantiated, assembled, and managed by the Spring IoC container.

37. What is the Spring MVC framework?

Spring MVC is a framework for building web applications following the Model-View-Controller design pattern.

38. What is AOP (Aspect-Oriented Programming)?

AOP is a programming paradigm that allows separation of cross-cutting concerns, such as logging and security.

39. What is the purpose of Spring Boot?

Spring Boot simplifies the setup and development of new Spring applications by providing default configurations.

40. What is Hibernate?

Hibernate is an ORM framework that maps Java objects to database tables, simplifying database interactions.

41. What are Hibernate annotations?

Annotations provide a way to define mappings between Java classes and database tables without XML configuration.

42. What is the Hibernate Session?

A Hibernate Session is an interface that provides methods for interacting with the database, such as saving, updating, and deleting entities.

43. What is HQL?

Hibernate Query Language (HQL) is an object-oriented query language used to perform database operations in Hibernate.

44. What is the difference between save() and persist() in Hibernate?

save() returns the identifier of the saved entity, while persist() does not return anything and is used for entity state management.

45. What is caching in Hibernate?

Caching improves performance by storing frequently accessed data in memory, reducing database access.

46. What is the difference between first-level and second-level cache in Hibernate?

The first-level cache is session-scoped, while the second-level cache is session factory-scoped and shared across sessions.

47. What is a transaction in EJB?

A transaction is a sequence of operations that are treated as a single unit of work, ensuring data integrity.

48. What is RESTful web services in Spring?

RESTful web services are services that follow REST architecture, allowing clients to access and manipulate resources using standard HTTP methods.