Using the following program make the modifications below: import java.util.Scanner;

public class PetFoodArrow

$\{$

public static void main$($String$[]$ args$)$

$\{$

String input $=""$;

char foodGrade $=\text{'}\text{'}$;

foodGrade $=$ getInput$()$;

while$($foodGrade $!=\text{'}$X$\text{'})$

$\{$

input $=$ getGrade$($foodGrade$)$;

prinout$($foodGrade$,$ input$)$;

foodGrade $=$ getInput$()$;

$\}$

input $="$

End of the program!

$"$;

prinout$($foodGrade$,$ input$)$;

$\}$

$/*$

Methods' Definitions

$*/$

public static char getInput$()$

$\{$

String$[]$ mssgs $=\{$ "Our pet food is available in grades A$,$ B$,$ and C$.",$

"Which do you want pricing for? $\{$X to stop$\}$: $"\}$;

Scanner keyboard $=$ new Scanner$($System$.$in$)$;

System.out.print$($mssgs$[0]+($char$)10+$ mssgs$[1])$;

return keyboard.nextLine$().$toUpperCase$().$charAt$(0)$;

$\}$

public static String getGrade$($char fudGrade$)$

$\{$

String iO $=""$;

String$[]$ messash $=\{"$

Food grade $","$ costs $30$ cents per lb$.$

$",$

$"$ costs $20$ cents per lb$.$

$","$ costs $15$ cents per lb$.$

$",$

$"$

Invalid choice.

$"\}$;

iO $=$ switch$($fudGrade$)$

$\{$

case $\text{'}$A$\text{'}->$ messash$[0]+$ fudGrade $+$ messash$[1]$;

case $\text{'}$B$\text{'}->$ messash$[0]+$ fudGrade $+$ messash$[2]$;

case $\text{'}$C$\text{'}->$ messash$[0]+$ fudGrade $+$ messash$[3]$;

default $->$ messash$[4]$;

$\}$;

return iO;

$\}$

public static void prinout$($char fudGr, String incoming$)$

$\{$

if$($fudGr $!=\text{'}$X$\text{'})$

System.out.println$($incoming$)$;

else

System.out.println$($incoming$)$;

$\}$

$\}$

a$.$ Change it so that it uses JOptionPanes for input and output instead of Scanners

b$.$ Rename it PetFoodFin

c$.$ Prompt the user for the pet food grade AND the number of pounds they want to purchase

d$.$ Calculate the bill for the purchase by multiplying the price per$-$pound by the pounds purchased

e$.$ Change the switch statement to a switch expression that returns a double value containing the price; the default case should return a $0\mathrm{.}0$

f$.$ Your program should handle the possibility that users might enter lower case characters for the pet food grade

g$.$ Write a local method named getInput$()$ that uses a conditional operator to prompt you to enter the pet food grade or the number of pounds the client wants to

purchase. In this method declare an icon using the image puppy.jpg and a String array that contains the following elements:

"InOur pet food is available in three grades:", $"$A$,$ B$,$ and C$.$ InWhich do you want pricing for? $\{$Enter X to stop$\}?",$ "InHow many pounds do you want?"

h$.$ Write another local method named prinout$()$ that displays the cost of each grade of pet food and the cost of the poundage purchased or displays the average sales'

value. In this method declare an icon using the image puppy.jpg and a String array that contains the following elements:

"InGrade $",$ "sells for $",$ "Your $",$ "Ibs. purchase $=",$ "cents per Ib$.",$ "InThe average sales totaled $",$ "Summary Screen" and "Average Screen"

i$.$ Create a class named PetFood using the UML diagram below:.

j$.$ Use the PetFood class in your main method as well as the Average class to accumulate, count and average total purchases.

k$.$ The switch expression will be contained in the getPrice$()$ method

I. If the price returned by getPrice$()$ is zero, don't prompt for the pounds, don't calculate the total cost, don't accumulate or count; just print a message that says "Invalid

choice!".