IBM Interview Experience As A Java Developer

I got a call from a C2H company for IBM as a Java Developer at the Pune location for 3+ years of experience. They were giving me a 20% hike on my previous offer which wasn’t a bad deal at all. So, my F2F was arranged for the Yerwada location (Pune). The interview was quite fine though I was not selected.

Interview Questions asked majorly on Core Java and SpringBoot

1. OOPs in a very detailed manner
2. Object class methods (clone method was asked in detail like Deep copy vs Shallow copy)
3. HashMap Internal working in details and rehashing mechanism
4. Multithreading and Executors framework
5. Java 8 features and gave some Streams API problems
6. Hibernate and data connection pooling
7. Indexes in SQL
8. Asked to write a query to find all employees having the second highest salary
9. Difference between Primary Key and Unique Key
10. Various annotations in SpringBoot in detail and internal implementations or how they work and how to configure them manually
11. MicroServices Communication (API Gateway, RestTemlate)
12. JUnit and Mockito (Annotations used in SpringBoot testing and their meaning in detail) ( I don’t have any testing knowledge)
13. Do you have any questions (asked about the project’s nature)

They gave me detailed feedback out of 5 for every topic and where I have to excel.

• Java – 3.5/5 (was unable to tell about multithreading in detail)
• SpringBoot – 2.5/5 (Just knows abstract things, doesn’t know internal implementations and configurations)
• Testing – 1/5 (Don’t have any Testing knowledge, just knows Postman)
• MySQL – 3/5 (Knows how to write basic queries but don’t know to create RANK, ROW Number keywords)
• Microservices – 2.5/5 (knows basics only)

Overall, it was a great experience and it feels good when anyone gives genuine reasons for rejections. They required the candidate’s average score should be 3+ and mine was 2.5. I would recommend applying to IBM.