Chapter 15, Problem 21E

Explanation of Solution

Adding the “switchPairs” method in “ArrayIntList” class:

//definition of "ArrayIntList" class

public class ArrayIntList

{

    //declare the required variables

    private int[] elementData;

    private int size;

    //refer the remaining methods in the textbook

    //definition of "switchPairs" method

    public void switchPairs()

    {

/*iterate "i" is until it reaches "size-1" value*/

        for (int i = 0; i < size - 1; i++)

        {

            //declare the variable and seth te value

            int temp = elementData[i];

 �...