Java Interview Questions and Answers
Java is the most used language in top companies such as Uber, Airbnb, Google, Netflix, Instagram, Spotify, Amazon, and many more because of its features and performance. In this article, we will provide 200+ Core Java Interview Questions tailored for both freshers and experienced professionals.
- Java Basics & Program Flow
- Java Core Concepts
- Object-Oriented Programming (OOP)
- Collections & Generics
- Advanced Topics
To do well in interviews, you need to understand core syntax, OOP concepts, Collections Framework, memory handling and advanced features.
1. Core Concepts:
Variables & Data Types, Arrays, Strings & String Classes, Interfaces, Memory Model (Stack vs Heap), Garbage Collection, Shallow vs Deep Copy, Immutable Objects, Object-Oriented Programming (Classes, Objects, Inheritance, Polymorphism, Abstraction, Encapsulation).
2. Advanced Topics:
Exception Handling, Generics, Collections Framework, Multithreading, Lambda Expressions & Functional Interfaces, Streams API, Annotations, Reflection, Design Patterns (Singleton, Factory, Observer), Java 8+ Features.
