Persistent Systems Interview Question

1. How does Hashmap works internally. 1.2. Hasmap vs Hashtable vs SynchronizedHashmap 2. How to reverse array 3. What is synchronized keyword? and lot many questions followed it up. 4. Exceptions (Specially hierarchy related) 5. Spring Basics 6. Spring annotations 7. Hibernate Basics And Yes In MR round the interviewer may like to test your basic logic. He asked me to solve a puzzle like: How to get 2L water from using a 5L and 3L Bucket. and similarly 4L water.