random file access and GUI

I have two assignments i must complete in two days which I don't know much about.
The first one:

Quote:

---

Write a program which allows the user to manage a random file of 15 maximum students who are taking this on-line course. Each student can have 6 different marks assigned to them: Thinking, Applications, Communications, Thinking, Exam, and Final Mark. Use the percentage breakdowns for this course to determine the final mark. Because students in on-line courses are at different points in the course, random access has been choosen. From a menu give the user the following options:

* enter initial class list of all student names
* add/delete a student
* enter a mark (Thinking, Applicatinos, Communications, Knowledge or Exam)
* modify a mark (Thinking, Applicatinos, Communications, Knowledge or Exam)
* calculate final mark

---

For this assignment, I am having trouble figuring out how to tackle the assignment. I am thinking of doing arrays but I don't know how to random file access with arrays. Also I'm not sure whether I should read the file under each function.
The second one: is about GUI. For now, I just need some good resources on GUI.

Here is my current class for the file accessing. This is only to contain methods of random file access, the actual menu, inputting and stuff is in a separate class.

Code:

---

// A class which defines a student record - StudentRecord
import java.io.*;
public class StudentRecord
{
    protected int studentnum;     
    protected String name;         
    protected int thinking, application, communication, knowledge, exam;   
    protected double finalmark;     
    protected static final int RECORD_SIZE = 57;

    // Constructor to read record from file
    public StudentRecord (RandomAccessFile input) throws IOException
    {
        //read student number
        studentnum = input.readInt();
        // read student name
        byte[] nameBytes = new byte [30];
        input.readFully (nameBytes);
        name = new String (nameBytes, 0);
        //read marks
        thinking = input.readInt();
        application = input.readInt();
        communication = input.readInt();
        knowledge = input.readInt();
        exam = input.readInt();
        finalmakr = input.readDouble();       
    }


    // Constructor uses data from keyboard
    public StudentRecord (int studentnum, String name, int thinking, int application, int communication, int knowledge, int exam, double finalmark)
    {
        this.studentnum = studentnum;
        this.name = name;
        this.thinking = thinking;
        this.application = application;
        this.communication = communication;
        this.knowledge = knowledge;
        this.exam = exam;
        this.finalmark = finalmark;
    }



    // Method to get student number
    public int getStudentnumber ()
    {
        return studentnum;
    }


    // Method to get student name
    public String getName ()
    {
        return name;
    }


    // Method to get thinking
    public String getThinking ()
    {
        return thinking;
    }


    // Method to get application
    public double getApplication ()
    {
        return application;
    }

    //Method to get communication
    public int getCommunication ()
    {
        return communication;
    }


    // Method to get knowledge
    public int getknowledge ()
    {
        return knowledge;
    }

    //Method to get exam
    public int getExam ()
    {
        return exam;
    }


    // Method to get final mark
    public int getFinalmark ()
    {
        return finalmark;
    }

    // Method to get record size.
    public static int recordSize ()
    {
        return RECORD_SIZE;
    }


    // Method to write a record to file.
    public void write (RandomAccessFile output) throws IOException
    {
        //output student number
        output.writeInt(studentnum);
        //output student name
        name=fillspace(name,30);
        byte[] nameBytes = new byte [30];
        name.getBytes(0, name.length (), nameBytes, 0);
        output.write(nameBytes);
        //output marks
        output.writeInt(thinking);
        output.writeInt(application);
        output.writeInt(knowledge);
        output.writeInt(communication);
        output.writeInt(exam);
        output.writeDouble(finalmark);
    }


    // Method to fill extra string room with spaces
    public static String fillspace (String word, int lengthtofill)
    {
        int stringlength, x;
        stringlength = word.length ();
        for (x = stringlength; x <= lengthtofill-1 ; x++)
        {
            word = word + " ";
        }
        return word;
    }
}

---

My biggest problem is with the main class... I don't really understand how the data goes into an actual file.