Question

(In Java) Implement a class named Student. For this exercise, a student has a name, an id number and a list of the quiz scores they have taken. Supply an appropriate constructor and methods getName(), getId(), addQuiz(int score), getTotalScore(), getNumQuizzes() and getAverageScore(). The scores should be stored in an array or ArrayList. You should compute the total score and the average score when needed. The id number should be implemented with the assistance of a static instance variable. The first id assigned should be 50.

Write a separate class TestStudent, which includes a main method that fully tests your Student class.

Answer 1

import java.util.ArrayList;
import java.util.List;

class Student {
   private int id;
   private String name;
   private List<Integer> scores;
   // static variable to maintain the ID count
   // starting from 0
   private static int count = 100;

   /**
   * @param n
   * @param l
   */
   Student(String n, List<Integer> l) {
       name = n;
       id = count++;
       scores = l;
   }

   public String getName() {
       return name;
   }

   public int getId() {
       return id;
   }

   // add score to arraylis
   public void addQuiz(int s) {
       scores.add(s);
   }

   // returns total score
   public int getTotalScore() {
       int sum = 0;
       for (int a : scores)
           sum += a;
       return sum;
   }

   // returns average score
   public double getAverageScore() {
       return ((double) getTotalScore()) / scores.size();
   }
}

public class TestStudent {
   public static void main(String[] args) {
       List<Integer> list = new ArrayList<Integer>();
       list.add(90);
       list.add(80);
       list.add(86);
       Student s1 = new Student("Uday", list);
       System.out.println("Name : " + s1.getName());
       System.out.println("Id : " + s1.getId());
       System.out.println("Total : " + s1.getTotalScore());
       System.out.println("Average: " + s1.getAverageScore());

   }
}