Answer Posted / debapriya

See HasMap is used when u want to use key value pair
If u r storing Any Objects the better u write ur code for
hascode implementation ,the better the the retrieval process is

Set maintains order,each time u add a object ,it checks
whether it exists or not calling equals which in turn calls
the hashcode method(x.equals(y) means x.hashcode==y.hashcode)

List --->in case if u use Vector or ArrayList since both of
them implenets RandomAccessInterface so retrieval is faster
but addition or deletion is slower

LinkedList --->deletion or insertion is faster but does not
implemet RandomAccess interface

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