Confusion about overriding in the subclass

Question

So I was given the following GradedActivity class:

 public class GradedActivity
 {
    private double score;  // Numeric score

    public void setScore(double s)
    {
        if (s < 0)
        score = 0.0;
    else if (s > 100)
        score = 100.0;
        else
            score = s;
     }

    public double getScore()
    {
       return score;
    }


    public char getGrade()
   {
      char letterGrade;

      if (score >= 90)
         letterGrade = 'A';
      else if (score >= 80)
         letterGrade = 'B';
      else if (score >= 70)
         letterGrade = 'C';
      else if (score >= 60)
         letterGrade = 'D';
      else
         letterGrade = 'F';

      return letterGrade;
   }
}

and I was tasked with generating a constructor that accepts values for points Obtaned and pointsTotal as arguments, initializes them, and sets the corresponding score (points obtained divided by points total), accessors and mutators for pointsobtained and total.

So here is what I came up with:

public class ProgrammingAssignment extends GradedActivity 
{
   public int pointsObtained;
   public int pointsTotal;

   public ProgrammingAssignment(int p, int t)
   {

      pointsObtained = p;
      pointsTotal = t;
   } 

   public int getPointsObtained()
   {
      return pointsObtained;
   }

   public int getPointsTotal()
   {
      return pointsTotal;
   }

   public double getScore()
   {
     return pointsObtained / pointsTotal;
   }

   public void setPointsObtained(int p)
   {
      pointsObtained = p;

   }

   public void setPointsTotal(int t)
   {
      pointsTotal = t;
   }     
  }

Everything compiles without error, but getScore isn't computing obtained/total (it comes back 0) in my test class:

 public class PADemo
 {
   public static void main(String[] args)
   {
        ProgrammingAssignment p1 = new ProgrammingAssignment(28,30);
            GradedActivity p2 = new ProgrammingAssignment(0,30);

      System.out.println (p1.getPointsObtained());
      System.out.println (p1.getPointsTotal());
      System.out.println (p1.getScore());  
      System.out.println (p1.getGrade());  

      System.out.println (p2.getScore());  
      System.out.println (p2.getGrade());  

      p1.setPointsObtained(25);
      p1.setPointsTotal(40);
      System.out.println (p1.getScore());  
      System.out.println (p1.getGrade() == 'F');  
 }
 }

How do I obtain the score (points obtained/points total) with getScore()

Test class returns:

28
30
0.0
F
0.0
F
0.0
true

Answer 1

By the looks of it, the simplest thing to fix your problem would be to change getScore() to:

public double getScore()
   {
     return (pointsObtained * 100) / pointsTotal;
   }

What your code is doing is that it's giving you 0.93 instead of 93, and 0.93 gets truncated to 0 when put into an integer(as pointed out in the comments).