Java: book excercise concerning generics

I learn Java from a book and found the following excercise (in the generics chapter, assuming I know only ArrayList and no collections, etc):

“Create a generic class with a type parameter that simulates drawing an item at
random out of a box. This class could be used for simulating a random drawing.
For example, the box might contain Strings representing names written on a slip
of paper, or the box might contain Integers representing a random drawing for a
lottery based on numeric lottery picks. Create an add method that allows the user of the class to add an object of the specified type along with an isEmpty method that determines whether or not the box is empty. Finally, your class should have a drawItem method that randomly selects an object from the box and returns it.
If the user attempts to draw an item out of an empty box, return null. Write a
main method that tests your class.”

How should I approach this?Should I define a Box class whose each object is an arraylist?