Syntax error with variable

I am having errors below and I am confused why this is a Lab to make a storage spot for a students information.

import java.util.Arrays;

I have a problem with the square brackets below

public class Student {
    private String studentID;
    private String studentName;
    private String studentMajor;
    private double studentGPA;
    private String studentGrad;
    private long[] ;

And a problem with Student() below

    public Student(){
        studentID = "";
        studentName = "";
        studentMajor = "";
        studentGPA = 0;
        studentGrad = "";
    }   

    public Student(String stuID, String stuName, String stuMajor, double stuGPA, String stuGrad) {
        studentID = stuID;
        studentName = stuName;
        studentMajor = stuMajor;
        studentGPA = stuGPA;
        studentGrad = stuGrad;
    }

    public void setID(String ID) {
        studentID = ID;
    }

    public void setName(String name) {
        studentName = name;
    }

    public void setMajor(String major) {
        studentMajor = major;
    }

    public void setGPA(double GPA) {
        studentGPA = GPA;
    }

    public void setGrad(String Grad) {
        studentGrad = Grad;
    }

    public String getID() {
        return studentID;
    }

    public String getName() {
        return studentName;
    }

    public String getMajor() {
        return studentMajor;
    }

    public double getGPA() {
        return studentGPA;
    }

    public String getGrad() {
        return studentGrad;
    }

    public void printData() {
        System.out.println("Student ID: "+studentID);
        System.out.println("Student Name: " +studentName );
        System.out.println("Student Major: "+studentMajor); 
        System.out.println("Student GPA: "+ studentGPA); 
        System.out.println("Student Year of Graduation: " +studentGrad);
    }
}