“等級”無法解析為變量

Question

我有這個練習，問題是如何解決錯誤“成績”無法解析為變量，而無需在 class 老師中聲明它。 我想這是我的代碼中唯一的錯誤。 對我來說很明顯為什么然后在我的 output 中只有等級變量沒有分配，但我不知道如何解決它。

public class App {
    public static void main(String[] args) throws Exception {

        Student studentOne = new Student("FraPedu");
        Student studentTwo = new Student("FraIla");
        Teacher teacherOne = new Teacher();
        
        teacherOne.teacherName = "Tiziana";

        teacherOne.assignGrade(studentOne,10);
        teacherOne.assignGrade(studentTwo,10);
        studentOne.getStudentDetails();
        studentTwo.getStudentDetails();
    }
}

public class Student {

    public String name;
    public int grade;

    public Student(String studentName) {

        System.out.println("Student object has been created succesfully!");
        name = studentName;
    }

    public void getStudentDetails() {

        System.out.println("Student name and grade: " + name + " " + grade);        
    }
}

public class Teacher {

    public String teacherName;

    public Teacher() {

        System.out.println("Teacher object has been created succesfully!");
    }

    public void assignGrade(Student alum, int finalGrade) {

        grade = finalGrade; 
    }
}

Answer 1

您需要將成績分配給您傳遞給assignGrade方法的Student object。

public class Teacher {

    public String teacherName;

    public Teacher() {

        System.out.println("Teacher object has been created succesfully!");
    }

    public void assignGrade(Student alum, int finalGrade) {

        alum.grade = finalGrade; // << this is the line I changed
    }
}