swap list elements example

package com.usr.collections;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

public class SwapList {

       public static void main(String[] args) {

              List<String> list = new ArrayList<String>();

              addElementsToList(list);

              System.out.println("list elements before swaping:");

              displayList(list);

              System.out.println("......................");

              swapList(list);

              System.out.println("list elements after swaping:");

              displayList(list);

       }

       public static void addElementsToList(List<String> list) {

              list.add("one");

              list.add("two");

              list.add("three");

              list.add("four");

              list.add("five");

       }

       public static void swapList(List<String> list) {

              // public static void swap(List<?> list, int i,int j)

              // Swaps the elements at the specified positions in the specified list.

              // (If the specified positions are equal, invoking this method leaves

              // the list unchanged.)

              Collections.swap(list, 2, 4);

       }

       public static void displayList(List<String> list) {

              for (String temp : list) {

                     System.out.println(temp);

              }

       }

}

output 
list elements before swaping:
one
two
three
four
five
......................
list elements after swaping:
one
two
five
four
three