Chapter 9, Problem 3PE

a.

Explanation of Solution

Program:

File name: “Recording.java”

//Define a class named Recording

public class Recording

{

    //Declare the variables

    private String song;

    private String artist;

    private int playTime;

    //Define a set method that takes the Recording’s title

    public void setSong(String title)

    {

        //Assign the value

        song = title;

    }

    //Define a set method that takes the Recording’s artist

    public void setArtist(String name)

    {

        //Assign the value

        artist = name;

    }

    /*Define a set method that takes the Recording’s playing time*/

    public void setPlayTime(int time)

 �...

b.

Explanation of Solution

Program:

File name: “RecordingSort.java”

//Import necessary header files

import javax.swing.*;

//Define a class named RecordingSort

public class RecordingSort

{

    //Define a main method

    public static void main(String[] args)

    {

        //Declare an array of five Recording objects

        Recording[] recordings = new Recording[5];

        //Declare the variables

        int x;

        String song, artist, timeString, order, message = "";

        int time;

        //For loop to be executed until x exceeds 5

        for(x = 0; x < recordings.length; ++x)

        {

            //Prompt the user to enter a song for recording

            song = JOptionPane.showInputDialog(null,

            "Enter a song for recording " + (x + 1));

            //Prompt the user to enter an artist for recording

            artist = JOptionPane.showInputDialog(null,

            "Enter an artist for recording " + (x + 1));

            //Prompt the user to enter the time for the recording

            timeString = JOptionPane.showInputDialog(null,

            "Enter the time for the recording in seconds" + (x + 1));

            time = Integer.parseInt(timeString);

            //Declare a temp object

            Recording temp = new Recording();

            //Function Call

            temp.setArtist(artist);

            temp.setSong(song);

            temp.setPlayTime(time);

            //Assign the value

            recordings[x] = temp;

        }

        /*Prompt the user to enter the choice of displaying

        the objects in order by song title, artist, or playing time*/

        order = JOptionPane.showInputDialog(null,

         "By which field do you want to sort?\n" +

         "(S)ong, (A)rtist, or (T)ime");

        //If the user enters a choice, song title

        if(order.charAt(0) == 'S')

            //Function call

            sortBySong(recordings);

        //If the user enters a choice, Artist

        else

        if(order.charAt(0) ==   'A')

            //Function call

            sortByArtist(recordings);

        //Else the user enters a choice, playing time

        else

            //Function call

            sortByTime(recordings);

        //For loop to be executed until x exceeds 5

        for(x = 0; x < recordings.length; ++x)

        //Print the message

message = message + "\nartist: " + recordings[x].getArtist() +

"    song: " + recordings[x].getSong() + "    time: " +

            recordings[x].getPlayTime();

        JOptionPane.showMessageDialog(null, message);

    }

    /*Define a method to sort the Recording objects in

    artist order*/

    public static void sortByArtist(Recording[] array)

    {

        //Declare the variables

        int a,b;

        Recording temp;

        String stringB, stringBPlus;

        int highSubscript = array.length - 1;

        //For loop to be executed until a exceeds highSubscript

        for(a = 0; a < highSubscript; ++a)

//For loop to be executed until b exceeds highSubscript

            for(b = 0; b < highSubscript; ++b)

            {

                stringB = array[b]...