Cognizant Software Engineer Java Developer interview questions

Java basics Collections Multithreading Oops concepts

1. HashMap, hashtable differ 2. Exceptions and types of exceptions 3. Internal working of hashmap and HashSet 4. collection used to remove/doesn't allow duplicates 5. What is a concurrent hashmap 6. Db query to write an inner join 7. Stream, lambda expressions query 8. What is an interface 9. What is a lambda expression 10. What is the stored procedure 11. Can we have catch() without try 12. can we have try without catch 13. Some db, stream API questions are also asked 14. Some aptitude questions