list of list in java

/**
 * @author lautturi.com 
 * Java example: creating a list of lists in java
 */

import java.util.*;

public class Lautturi {

	public static void main(String[] args) {
		ArrayList<List<Integer>> listOfLists = new ArrayList<List<Integer>>();

		List<Integer> list1 = new ArrayList<Integer>();
		list1.add(1);
		list1.add(2);
		listOfLists.add(list1);

		List<Integer> list2 = new ArrayList<Integer>();
		list2.add(3);
		list2.add(4);
		listOfLists.add(list2);

		System.out.println("list1:" + list1);
		System.out.println("list2:" + list2);
		System.out.println("listOfLists:" + listOfLists);

	}
}

output:

list1:[1, 2]
list2:[3, 4]
listOfLists:[[1, 2], [3, 4]]