J2EE Interview Questions -1

1. What is Collection?
2. Why do you create interfaces, and when MUST you use one?
3. How to make application thread-safe?
4. How to make application thread-safe?
5. What synchronization constructs does Java provide? How do they work?
6. If i create a object which is to be serialized then do I need to implement any methods?
7. How can we write our own array list without using collections?
8. Can we make constructor STATIC?
9. Are constructors inherited? Can a subclass call the parent's class constructor? When?
10. How can we do bug tracking in an intranet project for a pharmaceutical company using java,jdbc,ejb sevlet using oracle as backend can anyone guide?
11. What is the corresponding Layout for Card in Swing ?
12. Can u kill thread manually? What is the disadvantage?
13. How can we invoke private method using refleciotn API(AccessibileObje ct class)?
14. What happen if we write many curly braces in main method and write println method inside it program will compile or not?
    
15. How can you load DLL files when your java class is loading first time ?
16. Size of object in java : Is there any way in java to find of size of an object ?( like sizeof() operator of C/C++ )
17. Have you ever used HashTable and Dictionary ?
18. Is is true that JAVA is not 100% object oriented language ?
19. Can we write return statement in try catch or finally block. suposse we write return 0 in try catch or finally. can we do.
20. Is there any provision in java to find the address of a particular memory location?(like & in 'C' language)