Write a Java program that opens the file reads all the Grade

Write a Java program that opens the file, reads all the Grade from the file, and using a method calculates and displays the following A) Displays the grades with their letter values (80 - B) B) the sum of the Grades in the file C) the average of the Grades in the file

Solution

GradeRead.java

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class GradeRead {

   public static void main(String[] args) throws FileNotFoundException {  
       Scanner scan1 = new Scanner(System.in);
       System.out.print(\"Enter the file name: \");
       String fileName = scan1.next();
       File file = new File(fileName);
       if(file.exists()){
           Scanner scan = new Scanner(file);
           calculateGradeDetail(scan);
       }
       else{
           System.out.println(\"Input does not exist\");
       }

   }
   public static void calculateGradeDetail(Scanner scan){
       int sum = 0;
       int count = 0;
       char gradeLetter = \'\\0\';
       while(scan.hasNextInt()){
           count++;
           int n = scan.nextInt();
           sum = sum + n;
           if(n >=90 && n<=100){
               gradeLetter = \'A\';
           }
           else if(n >=80 && n<90){
               gradeLetter = \'B\';
           }
           else if(n >=70 && n<80){
               gradeLetter = \'C\';
           }
           else if(n >=60 && n<=70){
               gradeLetter = \'D\';
           }
           else {
               gradeLetter = \'E\';
           }
           System.out.println(\"Grade: \"+gradeLetter+\" - \"+n);
       }
       System.out.println(\"The sum of the Grades in the file: \"+sum);
       double average = sum/(double)count;
       System.out.println(\"the average of the Grades in the file: \"+average);
       System.out.println();
   }

}

Output:

Enter the file name: D:\\\\grade.txt
Grade: D - 60
Grade: C - 70
Grade: B - 80
Grade: A - 90
Grade: A - 100
Grade: E - 40
Grade: E - 50
Grade: D - 60
The sum of the Grades in the file: 550
the average of the Grades in the file: 68.75

Grade.txt

60
70
80
90
100
40
50
60