panel y GridBagLayout

[valdo_kof]

tengo el siguiente codigo;

Código Java:

public class Ventana extends JPanel //con JFrame visualiza lo que necesito realizar
 {    
     public Ventana() throws BarcodeException, FileNotFoundException, OutputException, IOException
     {
        super ();
         this.setLayout(new GridBagLayout());
         this.setSize(470, 350);
          this.setBackground(Color.white);
         GridBagConstraints constraints = new GridBagConstraints();
       Barcode barcode = BarcodeFactory.createCode39("N14U-93110-00",false);
barcode.setDrawingText(false);
 barcode.setBarHeight(50);
 barcode.setBarWidth(2);
 FileOutputStream fos = new FileOutputStream("c:/N14U-93110-00.jpeg");
  BarcodeImageHandler.writeJPEG(barcode, fos);
   ImageIcon icon = new ImageIcon("c:/N14U-93110-00.jpeg");
Barcode barcode_q = BarcodeFactory.createCode39("Q8",false);
barcode_q.setDrawingText(false);
 barcode_q.setBarHeight(50);
 barcode_q.setBarWidth(2);
 FileOutputStream fos_q = new FileOutputStream("c:/q8.jpeg");
  BarcodeImageHandler.writeJPEG(barcode_q, fos_q);
   ImageIcon icon_q = new ImageIcon("c:/q8.jpeg");
   Barcode barcode_l = BarcodeFactory.createCode39("L1111",false);
barcode_l.setDrawingText(false);
 barcode_l.setBarHeight(50);
 barcode_l.setBarWidth(2);
 FileOutputStream fos_l= new FileOutputStream("c:/l1111.jpeg");
 BarcodeImageHandler.writeJPEG(barcode_l, fos_l);
 ImageIcon icon_l = new ImageIcon("c:/l1111.jpeg");
 JLabel country=new JLabel("HARADA INDUSTRY OF AMERICA");
 country.setFont(new java.awt.Font("Arial", 1, 14));
 JLabel item=new JLabel("ITEM No.");
 item.setFont(new java.awt.Font("Arial", 1, 8));
 JLabel item_comp=new JLabel("(N)");
 item_comp.setFont(new java.awt.Font("Arial", 1, 8));
 JLabel item_no=new JLabel("14U-93110-00");
 item_no.setFont(new java.awt.Font("Arial", 1, 20));
 JLabel image=new JLabel();
 image.setIcon(icon);
 JLabel espacio=new JLabel(" ");
 JLabel qty=new JLabel("8");
 qty.setFont(new java.awt.Font("Arial", 1, 20));
 JLabel Quantity=new JLabel("Quantity");
 Quantity.setFont(new java.awt.Font("Arial", 1, 8));
 JLabel q=new JLabel("(Q)");
 q.setFont(new java.awt.Font("Arial", 1, 8));
 JLabel image_q=new JLabel();
 image_q.setIcon(icon_q);
 JLabel l=new JLabel("1111");
 l.setFont(new java.awt.Font("Arial", 1, 20));
 JLabel lot=new JLabel("Lot No.");
 lot.setFont(new java.awt.Font("Arial", 1, 8));
 JLabel lo=new JLabel("(L)");
 lo.setFont(new java.awt.Font("Arial", 1, 8));
 JLabel image_l=new JLabel();
 image_l.setIcon(icon_l);
 JLabel c=new JLabel("28200 9E000");
 c.setFont(new java.awt.Font("Arial", 1, 20));
 JLabel cus=new JLabel("Customer No.");
 cus.setFont(new java.awt.Font("Arial", 1, 8));
 JLabel country2=new JLabel("ASSEMBLED IN MEXICO.");
 country2.setFont(new java.awt.Font("Arial", 1, 14));
         constraints.gridx = 1;
         constraints.gridy = 0;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
        constraints.weightx=0;
        constraints.weightx=0;
         this.add (country, constraints);
         constraints.gridx = 0;
         constraints.gridy = 1;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (item, constraints);
         constraints.gridx = 0;
         constraints.gridy = 2;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (item_comp, constraints);
         constraints.gridx = 1;
         constraints.gridy = 2;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (item_no, constraints);
     constraints.gridx = 1;
         constraints.gridy = 3;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (image, constraints);
         constraints.gridx = 0;
         constraints.gridy = 4;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (espacio, constraints);
         constraints.gridx = 0;
         constraints.gridy = 5;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (Quantity, constraints);
         constraints.gridx = 0;
         constraints.gridy = 6;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (q, constraints);
         constraints.gridx = 1;
         constraints.gridy = 6;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (qty, constraints);
         constraints.gridx = 1;
         constraints.gridy = 7;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (image_q, constraints);
         constraints.gridx = 0;
         constraints.gridy = 8;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (espacio, constraints);
         constraints.gridx = 0;
         constraints.gridy = 9;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (lot, constraints);
         constraints.gridx = 0;
         constraints.gridy = 10;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (lo, constraints);
         constraints.gridx = 1;
         constraints.gridy = 10;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (l, constraints);
         constraints.gridx = 1;
         constraints.gridy = 11;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (image_l, constraints);
         constraints.gridx = 0;
         constraints.gridy = 12;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (espacio, constraints);
         constraints.gridx = 0;
         constraints.gridy = 13;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (cus, constraints);
         constraints.gridx = 1;
         constraints.gridy = 13;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (c, constraints);
         constraints.gridx = 1;
         constraints.gridy = 14;
         constraints.gridwidth = 1;
         constraints.gridheight = 1;
         this.add (country2, constraints);
          BufferedImage imagen = new BufferedImage(this.getWidth(), this.getHeight(), BufferedImage.TYPE_INT_RGB);
         Graphics g = imagen.getGraphics();
        this.paint(g);
       ImageIO.write(imagen,"jpg",new File("c:/prueba.jpg"));
     }
     public static void main(String args[]) throws BarcodeException, FileNotFoundException, OutputException, IOException{
     Ventana obj= new Ventana();
     obj.setVisible(true);
     }
}
 

lo ocupo para poder hacer el diseño de una etiqueta y guardarla en una imagen jpg

el codigo me crea la imagen pero solo me pone el panel en blanco sin ningun componente agregado en las lineas this.add (componente, constraints);

no se que estoy haciendo mal

si cambio public class Ventana extends JPanel por
public class Ventana extends JFrame

se puede ver el diseño de como necesito que quede mi imagen, bueno y tambien necesito encerrar cada segento en un rectangulo

con este codigo me crea los rectangulos q necesito y el tamaño adecuado en la cual debe de quedar mi imagen solo falta hacer q aparescan los componentes q se agregan con this.add (componente, constraints);

solo le agregue al codigo de arriba este pedacito

Código Java:

public class Ventana extends JFrame
 {
    
     public Ventana() throws BarcodeException, FileNotFoundException, OutputException, IOException
     {
        super ();
         this.setLayout(new GridBagLayout());
         this.setSize(300, 295);
.
.
.
         g.drawRect(1, 1, 296, 108);
         g.drawRect(1,109, 296, 72);
          g.drawRect(1,181, 296, 72);
          g.drawRect(1,253, 296, 38);
          g.setXORMode(Color.black);  
          this.paint(g);
          ImageIO.write(imagen,"jpg",new File("c:/prueba.jpg"));
     }
     public static void main(String args[]) throws BarcodeException, FileNotFoundException, OutputException, IOException{
     Ventana obj= new Ventana();
     obj.setVisible(true);
     }
}
 

si alguien puede ayudarme se los agradecere infinitamente