1  import java.util.ArrayList;

  2  

  3  public class MockGradeBook implements IGradeBook

  4  {

  5     private ArrayList<Double> scores;

  6  

  7     public MockGradeBook() { scores = new ArrayList<Double>(); }

  8  

  9     public void addScore(int studentId, double score) 

 10     {

 11        // Ignore studentId

 12        scores.add(score);

 13     } 

 14  

 15     public double getAverageScore(int studentId) 

 16     {

 17        double total = 0;

 18        for (double x : scores) { total = total + x; }

 19        return total / scores.size();

 20     }

 21  

 22     public void save(String filename)

 23     {

 24        // Do nothing

 25     }

 26  

 27     public void load(String filename)

 28     {

 29        // Add sample scores

 30        scores.add(1.0);

 31        scores.add(7.0);

 32        scores.add(2.0);

 33        scores.add(9.0);

 34     }

 35  }