- How to stop a thread from java program itself without using kill -9 command. - a Person class, create it's some objects, Person class has 4 fields : Name, salary , address and organization Now , create a hashset... Create 3 or 4 objects of Person class in hashset.. and store them in hashset in sorted manner on basis of name . If name is same in two objects , then sort them on basis of salary. - Hashmap, treemap, cyclic barrier, ciuntdown latch, - design patterns: builder design pattern - question : "whether u know spring or not. " Some basic idea. - Conversion constructor in Collections.. - ReentrantLocks Mostly collection and multi-threading... Some database questions like joins.

1.)Strings 2.) Collections 3.)Multithreading 4.)Design patterns 5.)OOP's concept