延长似乎没有发生

Question

作为我课堂作业的一部分，我必须手动将教科书中的代码复制到 jgrasp 中。

刚刚抄完最新的作业，我检查了一下我抄的是否完美，代码在下面。但是当我尝试编译它时，出现以下错误。

FinalExam.java:30: error: cannot find symbol
      setScore(numericScore); 
      ^
  symbol:   method setScore(double)
  location: class FinalExam
1 error

我在GradedActivity类中写了setScore方法所以FinalExam类应该继承了它，我唯一能想到的解释错误的想法是它出于某种原因没有继承？有没有人对它为什么不起作用有想法或建议？

public class GradedActivity
{
   private double score;
   
   public GradedActivity()
   {
      score = 0.0;
   }
   
   private void setScore(double s)
   {
      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;
   }
}

/**   
   This class determines the grade for a final exam.   
*/
public class FinalExam extends GradedActivity
{
   private int numQuestions;  // Number of questions
   private int numMissed;     // Questions missed
   
   public FinalExam(int questions, int missed)
   {
      double numericScore;
      
      numQuestions = questions;
      numMissed = missed;
      
      numericScore = 100.0 - (missed * getPointsEach());
      
      // Call the inherited setScore method to   
      // set the numeric score.
      setScore(numericScore); 
   }
   
   public int getNumQuestions()
   {
      return numQuestions;
   }
   
   public int getNumMissed()
   {
      return numMissed;
   }
   
   public double getPointsEach()
   {
      return 100.0 / numQuestions;
   }
}

Answer 1

private

函数是 not 继承的。变化

private void setScore(double s)

到

protected void setScore(double s)