Java Interview Questions to Prepare

🔹 Core Concepts

⿡ What are the key features of Java?

⿢ Explain the difference between JDK, JRE, and JVM.

⿣ What is a Java Virtual Machine (JVM), and how does it work?

⿤ Explain the concept of object-oriented programming (OOP).

⿥ How does Java achieve platform independence?

🔹 Object-Oriented Programming (OOP)

⿦ What are the four pillars of OOP?

⿧ Explain method overloading vs. method overriding.

⿨ What is the difference between an abstract class and an interface?

⿩ What is inheritance, and how is it implemented in Java?

🔟 Can you explain polymorphism with an example?

🔹 Collections Framework

⿡⿡ What is the difference between ArrayList and LinkedList?

⿡⿢ Explain HashMap vs. Hashtable.

⿡⿣ What are Generics in Java? Why are they used?

⿡⿤ How does ConcurrentHashMap work?

⿡⿥ What is the difference between Set and List?

🔹 Multithreading & Concurrency

⿡⿦ What is a thread in Java, and how is it created?

⿡⿧ Explain the difference between Runnable and Thread.

⿡⿨ What are synchronized blocks, and when would you use them?

⿡⿩ What is the volatile keyword in Java?

⿢⿠ What is a deadlock, and how can it be avoided?

🔹 Advanced Topics

⿢⿡ What is garbage collection, and how does it work?

⿢⿢ Explain Java's memory model.

⿢⿣ What is a Lambda Expression, and how is it used?

⿢⿤ How does Java implement exception handling?

⿢⿥ What are Streams in Java ?