Java interview questions for experienced professional

Below are few of the interview questions 

1. Name few bad java design
 [A]: Data in util , Stirng
2. if there is a Date format specified in a GUI page, what are  the possible issues which might arise?
[A]: 1) Data is not thread safe.
       2) It has to handle localization
3. Where should look if a JNI call is failing?
4.  What is edan space?
  All objects starts it life in Eden memory space, then move to survival space.
5. what  is composition Vs Generalization?
6. What are inner joins? Show example
7. Show examples for Singleton pattern you have used?
8. What are different types of hibernate transactions?
9. What are different types of injections in Spring?
10. What are the types of objects in Spring?
11. What are indexes and why do you do?
12. What is PermGen?
13. ArrayList Vs HashMap Vs TreeList?