Java Collections and Generics 11 | ArrayList in Java | Part 2 | addAll() | removeAll() | retainAll() 

retainAll is basically equivalent to intersections from Set Theory.

Bro.. I had one doubt it is possible to add group of element like array Eg: int arr[]={1, 2,3,4,5,6,7}; Like these .. I need to add set of element in a single add. Not, like these arr. add(1) ; arr. add(2) ; arr. add(3) ;