meaning of "?" in list

[Tanu Gulati]

as we know
List <Integer> list= new ArrayList<Integer>();
can contain only a list of Integers.

then what is the meaning and use of
List <?> list= new ArrayList<Integer>();
what is the use of "?" symbol in this?

[rakesh sugirtharaj]

It means a list of <<Anything>>. It is called as a wild card. The super class to all Generic collections is not Collection<Object> but a Collection<?>.May be this link could help you understand better.