This content originally appeared on DEV Community and was authored by FullStackPrep.Dev
Top 50 Java Interview Questions Every Developer Must Master
Java remains one of the most popular programming languages in the world. From startups to FAANG companies, Java interview questions are a staple for backend, full-stack, and system design roles.
If you’re preparing for your next job, here’s a curated list of essential Java questions you must know.
Core Java Questions
What is the difference between JDK, JRE, and JVM?
Explain OOP principles with examples.
How does Garbage Collection work in Java?
Difference between == and equals()?
What are checked vs unchecked exceptions?
Advanced Java Questions
How does Java memory model work (Heap, Stack, Metaspace)?
What are functional interfaces in Java 8?
Difference between HashMap, LinkedHashMap, and TreeMap?
What are streams and lambda expressions?
Explain multithreading vs concurrency.
Tricky Interview Questions
Can we override a static method in Java?
What happens if you put a custom object in a HashSet without overriding equals() and hashCode()?
Difference between final, finally, and finalize()?
Why is String immutable in Java?
What is the diamond problem and how does Java solve it?
System Design & Real-World Questions
How would you design a thread-safe Singleton in Java?
Explain producer-consumer problem in Java.
How would you build a high-concurrency system using ExecutorService?
Where to Find the Complete List
I’ve compiled a detailed guide of the top 50 Java interview questions with clear answers and explanations here 
Top 50 Java Interview Questions
Final Thoughts
Interviews aren’t just about writing code—they’re about how well you understand Java’s internals and can explain them clearly.
Mastering these 50 questions will give you the confidence to tackle anything from entry-level coding rounds to senior-level system design interviews.
Originally published via AnalogyAndMe.com
This content originally appeared on DEV Community and was authored by FullStackPrep.Dev