错误：使用BlueJ

Question

我是编码的新手。我正在使用BlueJ并且下面的代码编译得很好但是当我尝试使用add方法时，我得到一个非法的表达式开始。

据我所知，我没有嵌套在主要或任何东西的方法。

寻求一点帮助。只想测试add方法，其他方法还没有真正完成。

import java.util.ArrayList;


public class Roster
{
    static ArrayList<Student> myRoster = new ArrayList<>();

    public static void main(String[] args)
    {
        printAll();
    }

    public static void add(int studentID, String firstName, String lastName, String eMail, int age, int grade1, int grade2, int grade3)
    {
        int[] grades = {grade1, grade2, grade3};
        Student newStudent = new Student(studentID, firstName, lastName, eMail, age, grades);
        myRoster.add(newStudent);

    }

    /**
     * An example of a method - replace this comment with your own
     *
     * @param  y  a sample parameter for a method
     * @return    the sum of x and y
     */
    public static void remove(int studentID)
    {

    }

    public static void printAll()
    {
        for(int i = 0; i < myRoster.size(); i++)
        {
            myRoster.get(i).print();
        }
    }

    public static void printAverageGrade(int studentID)
    {
        for(Student eachStudent : myRoster)
        {
            double average = (eachStudent.getGrades()[0] + eachStudent.getGrades()[1] + eachStudent.getGrades()[2]) / 3.0;
            System.out.println("Student ID: " + eachStudent.getStudentID() + " Average Grade: " + average);
        }
    }

    public static void printInvalidEmails()
    {

    }
}

这是学生班，我得到的信息是在界面上（新的，不知道它叫什么，见下一句），上面写着“错误：非法开始表达”。当我右键单击类名册并转到add方法时会发生这种情况。然后我输入输入并得到错误。它在输入Roster.add（）之前在顶部显示状态，这对我来说似乎不对。不应该说myRoster.add？

如果它有帮助，从代码板（我甚至不知道这是否是我想添加“学生数据”的地方）如果我手动输入添加方法它会得到一个无法找到符号的错误 - 方法添加（.....）

public class Student
{
    private String firstName;
    private String lastName;
    private int studentID;
    private String eMail;
    private int age;
    private int[] grades;

    /**
     * Constructor for objects of class Student
     */
    public Student( int studentID, String firstName, String lastName, String eMail, int age, int[] grades)
    {
        setStudentID(studentID);
        setFirstName(firstName);
        setLastName(lastName);
        setEMail(eMail);
        setAge(age);
        setGrades(grades);

    }

    /**
     * Gets the student's ID
     * @return  studentID
     */
     public int getStudentID()
    {
        return studentID;
    }
    //Mutator
    public void setStudentID(int studentID)
    {
        this.studentID = studentID;
    }

    /**
     * Gets the first name of the student
     * @return firstName
     */
    public String getFirstName()
    {
        return firstName;
    }
    //Mutator
    public void setFirstName(String firstName)
    {
        this.firstName = firstName;
    }

    /**
     * Gets the last name of the student
     * @return lastName
     */
    public String getLastName()
    {
        return lastName;
    }
    //Mutator
    public void setLastName(String lastName)
    {
        this.lastName = lastName;
    }

    /**
     * Gets the eMail of the student
     * @return eMail
     */
    public String getEMail()
    {
        return eMail;
    }
    //Mutator
    public void setEMail(String eMail)
    {
        this.eMail = eMail;
    }

    /**
     * Gets the student's age
     * @return age
     */
    public int getAge()
    {
        return age;
    }
    //Mutator
    public void setAge(int age)
    {
        this.age = age;
    }

    /**
     * Gets the student's grades
     * @return grades
     */
    public int[] getGrades()
    {
        return grades;
    }
    //Mutator
    public void setGrades(int[] grades)
    {
        this.grades = grades;
    }

    public void print()//prints specific student data
    {
        System.out.println("Student ID:\t" + getStudentID() + 
                            "\tFirst Name:\t" + getFirstName() + 
                            "\tLast Name:\t" + getLastName() + 
                            "\tEmail:\t" + getEMail() + 
                            "\tGrade1:\t" + getGrades()[0] + 
                            "\tGrade2:\t" + getGrades()[1] + 
                            "\tGrade3:\t" + getGrades()[2]);
    }
}