如何用Java创建学生花名册

Question

I have a homework assignment problem that looks like this:

(20 pts) Create a Student class with the following:

• A private String variable named “name” to store the student's name
• A private integer variable named “UFID” that contains the unique ID number for this student
• A private String variable named “DOB” to store the student's date of birth
• A private integer class variable named numberOfStudents that keeps track of the number of students that have been created so far
• A public constructor Student(String name, int UFID, String dob)

• Several public get/set methods for all the properties

   getName/setName getUFID/setUFID getDob/setDob 

• Write a test program, roster.java, that keeps a list of current enrolled students. It should have methods to be able to enroll a new student and drop an existing student.

I'm not asking anyone to do this assignment for me, I just really need some general guidance. I think I have the Student class pretty well made, but I can't tell exactly what the addStudent() and dropStudent() methods should do - should it add an element to an array or something or just increments the number of students? The code I have so far looks like this.

public class Student {
    private String name;
    private int UFID;
    private String DOB;
    private static int numberOfStudents;

    public Student(String name, int UFID, String DOB) {
        this.name = name;
        this.UFID = UFID;
        this.DOB = DOB;
    }

    public String getDOB() {
        return DOB;
    }

    public void setDOB(String dOB) {
        DOB = dOB;
    }

    public int getUFID() {
    return UFID; }

    public void setUFID(int uFID) {
    UFID = uFID; }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getNumberOfStudents() {
        return numberOfStudents;
    }

    public void setNumberOfStudents(int numberOfStudents) {
        Student.numberOfStudents = numberOfStudents;
    }

    public static void addStudent(String name, int UFID, String DOB) {
        numberOfStudents++;
    }

    public static void dropStudent(String name) {
        numberOfStudents--;
    }
}

Any guidance as I finish this up would be greatly appreciated.

Answer 1

The assignment writes itself: you need a Roster class that owns and maintains a collection of Students:

public class Roster {
    private Set<Student> roster = new HashSet<Student>();

    public void addStudent(Student s) { this.roster.add(s); }

    public void removeStudent(Student s) { this.roster.remove(s); }
}