Serializing generic multiple 2d arrays

import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class Test {

    public static void main(String[] args) {

        List<List<ElementWrapper>> listA = randomList(5, 5);
        List<List<ElementWrapper>> listB = randomList(2, 3);
        List<List<ElementWrapper>> listC = randomList(4, 1);

        List<List<List<ElementWrapper>>> lists = new ArrayList<List<List<ElementWrapper>>>(3);
        lists.add(listA);
        lists.add(listB);
        lists.add(listC);

        List<List<List<ElementWrapper>>> newLists = null;

        printLists(lists);
        try {
            FileOutputStream fos = new FileOutputStream("testt.txt");
            ObjectOutputStream oos = new ObjectOutputStream(fos);
            oos.writeObject(lists);

            FileInputStream fis = new FileInputStream("testt.txt");
            ObjectInputStream iis = new ObjectInputStream(fis);
            newLists = (List<List<List<ElementWrapper>>>) iis.readObject();

        } catch (Exception e) {
            System.out.print(e);
        }

        System.out.println("After serialization");
        printLists(newLists);

    }

    public static List<List<ElementWrapper>> randomList(int row, int col) {
        ArrayList<List<ElementWrapper>> list = new ArrayList<List<ElementWrapper>>();
        for (int i = 0; i < row; i++) {
            ArrayList<ElementWrapper> innerList = new ArrayList<ElementWrapper>(col);
            for (int j = 0; j < col; j++) {
                double randNum = Math.random() * 100;
                ElementWrapper<Double> wrapper = new ElementWrapper<Double>();
                wrapper.element = randNum;
                innerList.add(wrapper);
            }
            list.add(innerList);
        }
        return list;
    }

    public static void printLists(List<List<List<ElementWrapper>>> lists) {
        for (List<List<ElementWrapper>> innerLists : lists) {
            for (List<ElementWrapper> list : innerLists) {
                for (ElementWrapper num : list) {
                    System.out.print(num + " ");
                }
                System.out.print("\n");
            }
            System.out.print("\n-----\n");
        }
    }

    public static class ElementWrapper<E> implements Serializable {
        public E element;

        @Override
        public String toString() {
            return element.toString();
        }
    }
}