//Creating arraylist example
ArrayList<String> list = new ArrayList<String>();
//Adding objects in arraylist
list.add("Mango");
list.add("Banana");
//Change the element (index,"new value")
list.set(1,"Dates");
//Return the 2nd element, because index starts from 0
System.out.println("Returning element: " + list.get(1)); // ArrayList implementation of List
List<String> list1 = new ArrayList<>();
// LinkedList implementation of List
List<String> list2 = new LinkedList<>();var list1 = List.of(1, 2);
var list2 = new ArrayList<>(List.of(3, 4));
var list3 = new ArrayList<String>();// Java code to demonstrate the concept of
// list of lists using iterator
import java.util.*;
class List_of_list {
// Iterate the 2D list using Iterator
// and print each element
public static <K> void
iterateUsingIterator(List<List<K> > listOfLists)
{
// Iterator for the 2D list
Iterator listOfListsIterator
= listOfLists.iterator();
System.out.println("[");
while (listOfListsIterator.hasNext()) {
// Type cast next() method
// to convert from Object to List<K>
List<K> list = new ArrayList<K>();
list = (List<K>)listOfListsIterator.next();
// Iterator for list
Iterator eachListIterator
= list.iterator();
System.out.print(" [");
while (eachListIterator.hasNext()) {
System.out.print(
" "
+ eachListIterator.next()
+ ", ");
}
System.out.println("], ");
}
System.out.println("]");
}
// Driver code
public static void main(String[] args)
{
// List of Lists
ArrayList<List<Integer> > listOfLists
= new ArrayList<List<Integer> >();
// Create N lists one by one
// and append to the list of lists
List<Integer> list1
= new ArrayList<Integer>();
list1.add(5);
list1.add(10);
listOfLists.add(list1);
List<Integer> list2
= new ArrayList<Integer>();
list2.add(1);
listOfLists.add(list2);
List<Integer> list3
= new ArrayList<Integer>();
list3.add(20);
list3.add(30);
list3.add(40);
listOfLists.add(list3);
// Iterate the 2D list
iterateUsingIterator(listOfLists);
}
}