Question

1. Using Java Write a class encapsulating the concept of student grades (50 elements) 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 can be randomly generated
• Accessor, mutator, toString, and equals methods
• A method returning the highest grade
• A method returning the average grade
• A method returning the lowest grade

Write a client class to test all the methods in your class to finish it off

Answer 1

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

class StudentGrades{
    int numStudents;
    int grades[];

    public StudentGrades(int numStudents) {
        this.numStudents = numStudents;
        grades = new int[numStudents];
        Random r = new Random();
        for(int i=0;i<numStudents;i++){
            grades[i] = r.nextInt(101);
        }
    }

    public int getNumStudents() {
        return numStudents;
    }

    public void setNumStudents(int numStudents) {
        this.numStudents = numStudents;
    }

    public int getHighestGrade(){
        int grad = 0;
        for(int x : grades){
            grad = Math.max(grad,x);
        }
        return grad;
    }

    public double getAverageGrade(){
        double total = 0;
        for(int x : grades){
            total += x;
        }
        return total/numStudents;
    }

    public int getLowestGrade(){
        int grad = 101;
        for(int x : grades){
            grad = Math.min(grad,x);
        }
        return grad;
    }

    public String toString(){
        return numStudents+" : "+ Arrays.toString(grades);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        StudentGrades that = (StudentGrades) o;
        return numStudents == that.numStudents &&
                Arrays.equals(grades, that.grades);
    }
}

class Main{
    public static void main(String[] args) {
        StudentGrades grades = new StudentGrades(10);
        System.out.println("Grades "+Arrays.toString(grades.grades));
        System.out.println("Minimum "+grades.getLowestGrade());
        System.out.println("Maximum "+grades.getHighestGrade());
        System.out.println("Average "+grades.getAverageGrade());
    }
}

OUTPUT :