Example program for Iterator in Java

import java.util.*; 
public class Demoiterator 
{
public static void main(String[] args) 
{

ArrayList al = new ArrayList(); 
 
al.add("Cat"); 
al.add("Apple"); 
al.add("Eye"); 
al.add("Ball"); 
al.add("Doll"); 
al.add("Fish"); 

System.out.print("Original contents of al: "); 
Iterator itr = al.iterator(); 
while(itr.hasNext()) 
{
   Object element = itr.next(); 
   System.out.print(element + " ");
} 
System.out.println(); 

ListIterator litr = al.listIterator(); 
while(litr.hasNext()) 
{
   Object element = litr.next(); 
   litr.set(element + "+");
} 
System.out.print("Modified contents of al: "); 
itr = al.iterator();
while(itr.hasNext()) 
{
   Object element = itr.next(); 
   System.out.print(element + " ");
} 
System.out.println(); 
 
System.out.print("Modified list backwards: "); 
while(litr.hasPrevious()) 
{
   Object element = litr.previous(); 
   System.out.print(element + " ");
} 
System.out.println(); 
} 
}


OUTPUT:


Original contents of al: Cat Apple Eye Ball Doll Fish 
Modified contents of al: Cat+ Apple+ Eye+ Ball+ Doll+ Fish+ 
Modified list backwards: Fish+ Doll+ Ball+ Eye+ Apple+ Cat+