Generic type for Arraylist of Arraylists

Question

In normal array list initialization, We used to define generic type as follows,

List list1 = new ArrayList();

B

Answer 1

Something like this:

List> matrix = new ArrayList>();
for (int i = 0; i < numRows; ++i) {
    List row = new ArrayList();
    // add some values into the row
    matrix.add(row);
}

Make the type of the inner List anything you want; this is for illustrative purposes only.