Need to create a GUI

Question

Ok I posted a while back but my code has completely changed.
I need to be able to convert my InvTest into a gui. So that it will do what it does now but in GUI. Is there not an easy way to do this?
Do I need to change or add any code in my Inventory.java or just my in my InvTest?
From my book it seems that JTextField will do what I am trying to accomplish?
Here is my current code.
INVENTORY.JAVA
//The Inventory class
public class Inventory {
     String productnumber;
     String name;
     int numberofunits;
     double priceperunit;
     // Create a new instance of Inventory
     // main constructor for the class
     public Inventory(String Item_Number, String Item_Name, int Items_in_Stock,
               double Item_Price) {
          productnumber = Item_Number;
          name = Item_Name;
          numberofunits = Items_in_Stock;
          priceperunit = Item_Price;
     public void setItemName(String Item_Name)
     // sets the items name
          name = Item_Name;
     public void setItemNumber(String Item_Number) { // Sets the Product =Number
                                                                 // for the item
          productnumber = Item_Number;
     public void setItemsInStock(int Items_in_Stock) { // sets the =number of
                                                                      // units in stock
          numberofunits = Items_in_Stock;
     public void setItemPrice(double Item_Price) { // sets the price of =the
                                                                 // item
          priceperunit = Item_Price;
     public String getItemName() { // returns the Product Name of this item
          return name;
     public String getItemNumber() { // returns the Product Number of the =item
          return productnumber;
     public int getItemsInStock() { // returns how many units are in stock
          return numberofunits;
     public double getItemPrice() { // returns the price of the item
          return priceperunit;
     public double getInventoryValue() { // returns the total value of =the stock
                                                  // for this item
          return priceperunit * numberofunits;
     public static double getTotalValueOfAllInventory(Inventory [] inv)
          double tot = 0.0;
          for(int i = 0; i < inv.length; i++)
               tot += inv.getInventoryValue();
          return tot;
     public String toString()
          StringBuffer sb = new StringBuffer();
          sb.append("DVD Title: \t").append(name).append("\n");
          sb.append("Item #:      \t").append(productnumber).append("\n");
          sb.append("Number in stock:\t").append(numberofunits).append("\n");
          sb.append("Price: \t").append(String.format("$%.2f%n", priceperunit));
          sb.append("Inventory Value:\t").append(String.format("$%.2f%n", this.getInventoryValue()));
          return sb.toString();
DVD.java
public class DVD extends Inventory {
     String genre;                         // Genre of the DVD
     double restockingFee;               // percentage that is added to the base price as a restocking fee
                                             //( actual inventory value will be the base inventory value plus
                                             // the base inventory value times this amount ) (value + (value * restockFee))
     public DVD(String genre, double restockingFee, String Item_Number, String Item_Name, int Items_in_Stock,
               double Item_Price) {
          super(Item_Number, Item_Name, Items_in_Stock, Item_Price);
          this.genre = genre;
          this.restockingFee = restockingFee;
          // TODO Auto-generated constructor stub
     //returns the value of the inventory, plus the restocking fee
     public double getInventoryValue() {
          // TODO Auto-generated method stub
          return  super.getInventoryValue() + (super.getInventoryValue() * restockingFee);
     public String toString()
          StringBuffer sb = new StringBuffer("Genre      \t").append(genre).append("\n");
          sb.append(super.toString());
          return sb.toString();
INVTEST.JAVA
public class InvTest
     public static void main(String args[])
          double restockFee = 0.05;
          // initialize a new inventory object
          DVD[] inventory = new DVD[10];
          inventory[0] = new DVD("Action" ,restockFee, "00623","Lost" , 10, 20.00);
          inventory[1] = new DVD("Action" ,restockFee, "00564","Friends" , 10,  12.00);
          inventory[2] = new DVD("Comedy",restockFee, "00222","Click", 10,  15.00);
          inventory[3] = new DVD("Family",restockFee,"00153","Cinderella" , 10, 18.00);
          inventory[4] = new DVD("Drama", restockFee,"00589","Titanic", 10, 24.00);
          inventory[5] = new DVD("Drama",restockFee,"00662","Summerland" , 10,10.00);
          inventory[6] = new DVD("Family",restockFee,"00558","Cars" ,  10,16.00);
          inventory[7] = new DVD("Action",restockFee,"00789","Batman" ,10, 9.00);
          inventory[8] = new DVD("Action",restockFee,"00987","Superman" ,10,9.00);
          inventory[9] = new DVD("Action",restockFee,"00556","Supergirl" ,10, 9.00);
          DVD temp[] = new DVD[1];
//          sorting the array using Bubble Sort
          for(int j = 0; j < inventory.length - 1; j++)
              for(int k = 0; k < inventory.length - 1; k++)
                  if(inventory[k].getItemName().compareToIgnoreCase(inventory[k+1].getItemName()) > 0)
                      temp[0] = inventory[k];
                      inventory[k] = inventory[k+1];
                      inventory[k+1] = temp[0];
                  }//end if
              }//end for loop
          }//end for loop
          // print the inventory information
          for(int j = 0; j < inventory.length; j++)
               System.out.println(inventory[j].toString());
          System.out.printf("Total value of all inventory = $%.2f" , Inventory.getTotalValueOfAllInventory(inventory));
          return;

Answer 1

textArea.setText(inventory[0].toString());should be
ta.setText(inventory[0].toString());to match the 'ta' of
javax.swing.JTextArea ta = new javax.swing.JTextArea(10,20);in earlier posts i used textArea.setText... just as a descriptive reference
but object references are very basic java - you should really try to understand
the basics before getting into swing.
anyway, here's something else to play around with
(you can put all this into the one .java file)
there's no pre-loaded DVD's, enter the data into the 4 textfields, then click add.
after adding a few titles, click one of the titles in the list.
note: there's no error handling in this
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
class Testing
  java.util.List dvds = new java.util.ArrayList();
  JTextField tfTitle = new JTextField(15);
  JTextField tfProductNumber = new JTextField();
  JTextField tfPrice = new JTextField();
  JTextField tfQuantity = new JTextField();
  DefaultListModel dlm = new DefaultListModel();
  JList list = new JList(dlm);
  public void buildGUI()
    JButton btn = new JButton("Add");
    JPanel p1 = new JPanel(new BorderLayout());
    JPanel p = new JPanel(new GridLayout(4,2));
    p.add(new JLabel("DVD Title: "));
    p.add(tfTitle);
    p.add(new JLabel("Product Number: "));
    p.add(tfProductNumber);
    p.add(new JLabel("Price per Unit: "));
    p.add(tfPrice);
    p.add(new JLabel("Quantity on Hand: "));
    p.add(tfQuantity);
    p1.add(p,BorderLayout.NORTH);
    JPanel p2 = new JPanel();
    p2.add(btn);
    p1.add(p2,BorderLayout.CENTER);
    JFrame f = new JFrame();
    f.getContentPane().add(p1,BorderLayout.NORTH);
    JScrollPane sp = new JScrollPane(list);
    f.getContentPane().add(sp,BorderLayout.CENTER);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.pack();
    f.setLocationRelativeTo(null);
    f.setVisible(true);
    btn.addActionListener(new ActionListener(){
      public void actionPerformed(ActionEvent ae){
        dvds.add(new DVD(tfTitle.getText(),tfProductNumber.getText(),
                                Double.parseDouble(tfPrice.getText()),
                               Integer.parseInt(tfQuantity.getText())));
        setList();
        clearTextFields();
    list.addListSelectionListener(new ListSelectionListener(){
      public void valueChanged(ListSelectionEvent lse){
        if(lse.getValueIsAdjusting() == false)
          DVD dvd = (DVD)dvds.get(list.getSelectedIndex());
          tfTitle.setText(dvd.title);
          tfProductNumber.setText(dvd.productNumber);
          tfPrice.setText(""+dvd.price);
          tfQuantity.setText(""+dvd.quantity);
  public void setList()
    dlm.clear();
    for(int x = 0, y = dvds.size(); x < y; x++)
      dlm.addElement((DVD)dvds.get(x));
  public void clearTextFields()
    tfTitle.setText("");
    tfProductNumber.setText("");
    tfPrice.setText("");
    tfQuantity.setText("");
    tfTitle.requestFocusInWindow();
  public static void main(String[] args)
    EventQueue.invokeLater(new Runnable(){
      public void run(){
        new Testing().buildGUI();
class DVD
  String title;
  String productNumber;
  double price;
  int quantity;
  public DVD(String t,String pn, double p, int q)
    title = t; productNumber = pn; price = p; quantity = q;
  public String toString(){return title;}
}