In Java, w rite a class encapsulating the concept of student grades on a test, a

Question

In Java, write a class encapsulating the concept of student grades on a test, assuming student grades are composed of a list of integers between 0 and 100.

Write the following methods:

--A constructor with just one parameter, the number of students; all grades will be randomly generated.

--Accessor, mutator, toString and equals methods

--A method returning an array of the grades sorted in ascending order.

--A method returning the highest grade

--a method returning the average grade

--a method returning the median grade[Hint: the median grade will be located in the middle of the sorted array of grades]

--A method returning the mode(the grade that occurs the most often)(Hint: create an array of counters; count how many times each grade occurs; then pick the maximum in the array of counters; the array index in the array of counter should correspond to the same index in the array of grades - use that index to find the grade value that is the mode)

Write a client class to test all your methods.

Explanation / Answer

import java.util.Arrays;
import java.util.Random;

public class Grade {
  
   private int grade[];
  
   public Grade(int number){
       grade = new int[number];
      
       // filling grade array with random numbers [0-100]
       Random random = new Random();
       for(int i=0; i<number; i++){
           grade[i] = random.nextInt(101);
       }
   }
  
   public int[] getGrade(){
       return grade;
   }
  
   @Override
   public String toString() {
       String str = "";
       for(int i=0; i<grade.length; i++){ // appending all grades
           str = str+grade[i]+" ";
       }
       return str;
   }
  
   public boolean equals(int g) {
       for(int i=0; i<grade.length; i++){
           if(grade[i] == g)
               return true;
       }
       return false;
   }
  
   public int[] sorted(){
       // creating a copy of original array
       int copy[] = Arrays.copyOf(grade, grade.length);
       Arrays.sort(copy);
       return copy;
   }
  
   public int max(){
       int max = grade[0];
       for(int i=1; i<grade.length; i++){
           if(grade[i] > max)
               max = grade[i];
       }
       return max;
   }
  
   public int min(){
       int min = grade[0];
       for(int i=1; i<grade.length; i++){
           if(grade[i] < min)
               min = grade[i];
       }
       return min;
   }
  
   public int median(){
       // getting sorted array
       int copy[] = sorted();
       int length = copy.length;
       // if length is even , them median will be
       if(length%2 == 0)
           return copy[length/2 - 1];
       else // odd length
           return copy[length/2];
   }
   public int mode(){
       //creating counting array
       int temp[] = new int[101];
       for(int i=0; i<grade.length; i++){
           temp[grade[i]]++;
       }
      
       //finding maximum in counting array
       int max = temp[0];
       int maxIndex = 0;
       for(int i=1; i<temp.length; i++){
           if(temp[i] > max){
               max = temp[i];
               maxIndex = i;
           }
       }
       return maxIndex;
   }
}

class Test{
   public static void main(String[] args) {
       Grade g = new Grade(15);
       System.out.println(g);
       System.out.println("Max: "+g.max());
       System.out.println("Min: "+g.min());
       System.out.println("Median: "+g.median());
       System.out.println("Mod: "+g.mode());
   }
}

/*

Output:

52 92 69 69 50 86 45 99 40 35 49 17 87 90 84
Max: 99
Min: 17
Median: 69
Mod: 69

*/

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