1. OOP Concepts - Provide real-world examples and explain usage in code. 2. Java Memory Management - Stack vs Heap, Garbage Collection, memory leaks, object creation and scope. 3. Exception Handling - Checked vs Unchecked exceptions - try-catch-finally, throws vs throw, custom exceptions. 4. Collections Framework - List, Set, Map interfaces and implementations - ArrayList vs LinkedList, HashSet vs TreeSet, HashMap vs LinkedHashMap 5. Multithreading and Concurrency - Thread lifecycle, Runnable vs Thread, synchronization, volatile, wait/notify - ExecutorService, Callable, Future

1) aptitude round online 2) 1 coding question challenge online 4) technical interview - questions on preference of language 3) HR round- attitude , confidence , future goals , working under pressure, communication