[Solved] CS 151 Programming Assignment #12

Goal: Compute a histogram of letter grades entered from the keyboard.Create a class named GradeHistogram that includes a method inputData () that reads a series of letter grades (A, B, C, D, F) from the user and counts the number of times each grade occurs. The grades are entered one per line. Enter a Z to signal the end of input. The grades can occur in any order. Accept both upper and lower case. For example A and a are the same grade. Dont assume any upper limit for the number of grades.Count the number of times a letter that is not a grade has been entered. The method showData() writes out the histogram.Write the program with a class definition of GradeHistogram and a separate class definition GHTester that contains the static main() method. The main() method creates a GradeHistogram object and call that objects inputData () method to read and process the data.Store the grade frequencies in an array of integers. Use a separate variable to contain the number of errors. You must use an array for this program since the purpose is practice with arrays.Do not write this program with just a single class. Write a driver class HistoTester which contains main(), which instantiates a GradeHistogram and uses its methods. Here is an example of the program working:Enter Grade: CEnter Grade: AEnter Grade: DEnter Grade: cEnter Grade: SEnter Grade: aEnter Grade: ZGrade Frequency A 2B 0C 2D 1F 1errors 1Class Average: 2.6Expect much more input than shown here.You will need: A while loop that keeps going until the user inputs a Z. You may also need to use the charAt() method of the String to get a single character from the users input.Program Outline:import java.util.*;public class GradeHistogram{. . . instance variables . . .public void inputData(){fill in here}public void showData(){fill in here}public double classAverage(){fill in here}}// Driver classpublic class HistoTester{public static void main ( String[] args ){GradeHistogram gradeHist = new GradeHistogram();gradeHist.inputData();gradeHist.showData();. . .}}What to turn in: Turn in GradeHistogram.java and HistoTester.java. At the top of yoursource files include your name and date in the comment header.