When preparing for Advance Java Viva Questions, understanding the core concepts is crucial for success. in this guide, we will explore the most frequently asked questions in Advanced Java viva and interviews, covering topics such as JDBC, servlets, JSP, and more. by focusing on commonly tested areas, you will be able to confidently answer the questions that often arise during such sessions.
Top 50 Advance Java Viva Questions and Answers
1. What is Advanced Java?
Answer : Advanced Java refers to the specialized version of Java programming that deals with web-based and enterprise-level applications. It includes topics such as servlets, JSP, JDBC, and frameworks like Hibernate and Spring.
2. What is the difference between JDK, JRE, and JVM?
Answer : JDK (Java Development Kit) is a software development environment for writing Java applications. JRE (Java Runtime Environment) provides the libraries and JVM (Java Virtual Machine) to run Java applications. JVM is responsible for executing Java bytecode on any platform.
3. What are Java Servlets?
Answer : Java Servlets are server-side Java programs that handle client requests and generate dynamic content on the web. they are used to extend the functionality of web servers.
4. What is the life cycle of a Servlet?
Answer : The life cycle of a Servlet consists of three methods: init(), service() and destroy(). The init() method initializes the servlet, service() processes client requests and destroy() is called before the servlet is destroyed.
5. What is the purpose of the doGet() and doPost() methods in servlets?
Answer : doGet() handles HTTP GET requests, typically for retrieving data, while doPost() handles HTTP POST requests, used for submitting data to the server.
6. What is JSP?
Answer : JavaServer Pages (JSP) is a technology that allows developers to create dynamic web pages using Java in combination with HTML, XML, or other document types. JSP is used for server-side web programming.
7. What is the difference between Servlets and JSP?
Answer : Servlets are Java programs used for handling server-side requests, while JSP allows embedding Java code directly into HTML pages for dynamic content. JSPs are more convenient for creating web page content, while Servlets are more powerful for request handling.
8. What is the MVC architecture in Java?
Answer : MVC (Model-View-Controller) is a design pattern that separates the application into three components: the model (data), the view (UI) and the controller (logic). It helps in managing complex applications.
9. What is JDBC?
Answer : Java Database Connectivity (JDBC) is an API that allows Java applications to connect and interact with databases. It enables executing SQL queries and retrieving results within Java programs.
10. What are the types of JDBC drivers?
Answer : There are four types of JDBC drivers: Type-1 (JDBC-ODBC bridge), Type-2 (native API driver), Type-3 (network protocol driver), and Type-4 (thin driver).
11. What is a PreparedStatement in JDBC?
Answer : A PreparedStatement is a precompiled SQL statement that can be executed multiple times with different parameters, improving performance and security by preventing SQL injection attacks.
12. How do you connect to a database in Java?
Answer : To connect to a database, use the JDBC DriverManager class, load the database driver and call the getConnection() method with the database URL, username and password.
13. What is the difference between Statement and PreparedStatement in JDBC?
Answer : A Statement is used for executing simple SQL queries, while a PreparedStatement is precompiled and allows parameterized queries, making it more efficient and secure.
14. What is Hibernate in Java?
Answer : Hibernate is an open-source Object-Relational Mapping (ORM) framework that simplifies database interaction by mapping Java objects to database tables, automating SQL queries and providing better performance.
15. What are the benefits of using Hibernate?
Answer : Hibernate simplifies database operations, provides automatic table creation, supports caching, handles transactions efficiently and abstracts SQL, allowing developers to focus on Java objects.
16. What is the difference between Hibernate and JDBC?
Answer : JDBC requires manual SQL query handling and database connection management, whereas Hibernate automates these processes, making it easier to work with databases and reducing boilerplate code.
17. What is Lazy Loading in Hibernate?
Answer : Lazy Loading is a feature in Hibernate where an entity or collection is not loaded from the database until it is accessed in the code, improving performance by avoiding unnecessary data retrieval.
18. What is the role of Spring Framework in Java?
Answer : The Spring Framework provides a comprehensive programming and configuration model for modern Java-based enterprise applications. It is known for its dependency injection, aspect-oriented programming and transaction management.
19. What is Dependency Injection in Spring?
Answer : Dependency Injection (DI) is a design pattern where objects are provided to a class instead of the class creating the objects itself. Spring handles the injection, allowing loose coupling and better testability.
20. What are the types of Dependency Injection in Spring?
Answer : There are two types of Dependency Injection: Constructor-based DI (injection through constructor parameters) and Setter-based DI (injection through setter methods).
21. What is Spring Boot?
Answer : Spring Boot is a framework that simplifies the creation of stand-alone, production-ready Spring applications. It provides embedded servers, auto-configuration and opinionated defaults to reduce boilerplate code.
22. What is an Embedded Server in Spring Boot?
Answer : An embedded server is a server (like Tomcat or Jetty) that runs within the application itself, rather than as a separate process. Spring Boot allows running web applications without needing external servers.
23. What is the difference between Spring and Spring Boot?
Answer : Spring provides a comprehensive framework for enterprise applications, while Spring Boot offers an easier, more opinionated way to set up Spring applications with minimal configuration and faster development cycles.
24. What is AOP in Spring?
Answer : Aspect-Oriented Programming (AOP) in Spring allows separation of cross-cutting concerns like logging, security and transaction management from the business logic, making code more modular.
25. What are annotations in Java?
Answer : Annotations are metadata that provide additional information to the compiler or runtime about the code. In Java, annotations are used to configure frameworks like Spring, Hibernate, and JUnit.
26. What is the purpose of the @Override annotation?
Answer : The @Override annotation indicates that a method is overriding a method from a superclass, ensuring that the method signatures match and improving code readability.
27. What is Java Reflection?
Answer : Reflection in Java is the ability to inspect and modify the behavior of classes, methods, and fields at runtime. It is commonly used in frameworks for dependency injection and dynamic proxy creation.
28. What is a Singleton Class in Java?
Answer : A Singleton Class is a class that can have only one instance during the application’s lifetime. It is commonly used for managing shared resources like database connections or logging mechanisms.
29. What is the Factory Design Pattern?
Answer : The Factory Design Pattern provides an interface for creating objects, but lets subclasses decide which class to instantiate. It is useful for object creation when the exact class is not known until runtime.
30. What is a Thread in Java?
Answer : A Thread is a lightweight process that enables multitasking in Java applications. Java provides the Thread class and the Runnable interface for creating and managing threads.
31. What is Synchronization in Java?
Answer : Synchronization ensures that only one thread accesses a critical section of code at a time, preventing data inconsistency in multithreaded environments.
32. What is the difference between Sleep() and wait() in Java?
Answer : The sleep() method pauses the execution of a thread for a specified period, while wait() causes the thread to wait until it is notified or interrupted, releasing any locks it holds.
33. What is a Deadlock in Java?
Answer : A Deadlock occurs when two or more threads are waiting indefinitely for resources held by each other, causing the program to freeze. Proper synchronization and resource management prevent deadlocks.
34. What are Lambda Expressions in Java?
Answer : Lambda Expressions provide a way to write concise and functional-style code in Java. They allow you to pass functionality as arguments, simplifying the code.
35. What is the Stream API in Java?
Answer : The Stream API is a feature in Java 8 that enables functional-style operations on collections, such as filtering, mapping and reducing, making code more expressive and easier to read.
36. What is the difference between Collection and Collections in Java?
Answer : Collection is the root interface of the Java Collections Framework, while Collections is a utility class that provides static methods for manipulating and working with collections.
37. What is the difference between List and Set in Java?
Answer : A List is an ordered collection that allows duplicates, while a Set is an unordered collection that does not allow duplicate elements.
38. What is a HashMap in Java?
Answer : A HashMap is a collection class that stores key-value pairs, where each key is unique. It provides constant-time performance for basic operations like insertion and retrieval.
39. What is a ConcurrentHashMap?
Answer : A ConcurrentHashMap is a thread-safe variant of HashMap that allows concurrent access by multiple threads without locking the entire map, improving performance in multithreaded applications.
40. What is Serialization in Java?
Answer : Serialization is the process of converting an object into a byte stream for storage or transmission. Deserialization is the reverse process, reconstructing the object from the byte stream.
41. What is the transient keyword in Java?
Answer : The transient keyword marks a variable that should not be serialized. when an object is serialized, the value of transient fields is not saved.
42. What is the difference between equals() and == in Java?
Answer : equals() compares the contents of two objects, while == compares their memory addresses to check if they refer to the same object.
43. What is the difference between final, finally, and finalize() in Java?
Answer : final is a keyword used to define constants or prevent inheritance, finally is a block that executes after a try-catch block and finalize() is a method used to clean up resources before garbage collection.
44. What is the Garbage Collection in Java?
Answer : Garbage Collection is the process by which the JVM automatically reclaims memory by destroying objects that are no longer referenced in the program.
45. What is the purpose of try-catch-finally in Java?
Answer : The try-catch-finally block is used to handle exceptions in Java. The try block contains code that may throw exceptions, catch handles the exceptions and finally executes code regardless of whether an exception occurred.
46. What is the throw keyword in Java?
Answer : The throw keyword is used to explicitly throw an exception in Java, enabling the programmer to trigger custom exceptions based on certain conditions.
47. What is the throws keyword in Java?
Answer : The throws keyword is used in method declarations to specify that a method may throw certain exceptions during its execution.
48. What is a custom exception in Java?
Answer : A custom exception is a user-defined exception class that extends the Exception class. It allows developers to create their own exceptions for specific error scenarios.
49. What is the purpose of the volatile keyword in Java?
Answer : The volatile keyword ensures that the value of a variable is always read from the main memory, not from the thread’s cache, ensuring visibility of changes to the variable across multiple threads.
50. What is the Executor Framework in Java?
Answer : The Executor Framework provides a high-level API for managing threads and asynchronous tasks. It abstracts the complexity of thread management, making it easier to write concurrent code.
In conclusion, mastering Advance Java Viva Questions will significantly enhance your understanding of key Java concepts, helping you excel in both interviews and exams. with a clear grasp of topics like JDBC, Hibernate, servlets, and multithreading, you will be well-prepared for any viva or technical interview. additionally, this guide offers original, SEO-optimized content designed to provide you with the most relevant information. continue practicing these questions to boost your confidence and succeed in your Advanced Java assessments.
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