🚀 Tricky Core Java Interview Questions – Must-Know for Java Developers!

💡 Are you preparing for Java interviews? Here’s a list of tricky Core Java questions that often confuse even experienced developers! 🎯
🔥 Strings & Memory
🔹 Why is String immutable in Java?
🔹 Difference between StringBuffer and StringBuilder?
🔹 What happens when you modify a string stored in the String Pool?

🏗 Object & Classes
🔹 Can we override static methods? Why?
🔹 What happens if a constructor is private?
🔹 Can we make a class immutable? How?

⚠ Exception Handling
🔹 What happens if an exception is thrown in a finally block?
🔹 Can we have try without catch?
🔹 Checked vs. Unchecked exceptions?

🚦 Multi-threading
🔹 Difference between wait(), sleep(), and yield()?
🔹 Can synchronized methods run in parallel?
🔹 What happens if we call run() instead of start() in a thread?

📚 Collection Framework
🔹 Difference between HashMap and ConcurrentHashMap?
🔹 Can we store null keys in HashMap and Hashtable?
🔹 Why is ArrayList faster than LinkedList for searching?

🔄 JVM & Memory Management
🔹 How does the Garbage Collector work in Java?
🔹 What is PermGen vs. Metaspace?
🔹 What happens if an object has only finalize() and no references?

🤯 Miscellaneous
🔹 What happens if we modify a HashMap while iterating?
🔹 Can we have multiple public classes in a Java file?
🔹 Why does Java not support multiple inheritance?

🔥 Watch More Java Interview Questions:
🔹 Top Java 8 Coding Problems: https://bit.ly/java8coding
🔹 Top Java Interview Programs : https://bit.ly/3QGJFAf
🔹 Java Full Stack Course: https://bit.ly/412pFNc
🔹 Real Time Java videos : https://bit.ly/3Dn3h9l

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📘 Master SOLID Principles in Java with Real-Time Examples
Welcome to the ultimate Java developer guide! In this series, we break down the SOLID principles to help you write clean, scalable, and interview-ready code. Perfect for Java beginners to advanced devs working with Spring Boot & Microservices.

🎥 Watch All 5 SOLID Principle Videos:

🔹 S – Single Responsibility Principle
👉 https://youtu.be/qCtw5M59tb0

🔹 O – Open/Closed Principle
👉 https://youtu.be/E0Bh3xIHpm4

🔹 L – Liskov Substitution Principle
👉 https://youtu.be/BMEkPAZBvEc

🔹 I – Interface Segregation Principle
👉 https://youtu.be/5o57KB9qqVs

🔹 D – Dependency Inversion Principle
👉 https://youtu.be/q6H2Dab7Wlg

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Topic : REACT JS LIVE SESSIONS @ 8 AM IST
Major Project : ECommerce Application + RazroPay Payment Gateway Integration
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When: Jul 30, 2025 08:00 AM

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Register in advance for this meeting:
https://us02web.zoom.us/meeting/register/_Trhf4AoTb-DAuVEF2Cffg

After registering, you will receive a confirmation email containing information about joining the meeting.