Drag and drop probleme java

package DragandDrop; 


 import java.awt.Dimension; 
 import java.awt.Graphics; 
 import java.awt.Image; 
 import java.io.File; 
 import java.io.IOException; 
import javax.imageio.ImageIO; 
import javax.swing.JComponent; 

   
 public class CartePuce extends JComponent { 
   
  private String Num="192-1-25-21"; 
  private String Nom="Mr.snoop dog"; 
  public CartePuce(String num,String nom) 
  { 
   this.Num=num; 
   this.Nom=nom; 
  this.setMinimumSize(new Dimension(198,125)); 
  } 
   
   
  public void enableDrag() { 
       
         addMouseListener(new DragAndDropListener()); 
     } 
  public void setNom(String nom) { 
          
         this.Nom=nom; 
     } 

     
     public void setNum(String num) { 
          
        this.Num=num; 
     } 
   public String getNom() { 
          
         return Nom; 
     } 

     
     public String getNum() { 
          
         return Num; 
     } 
    
   
     public CartePuce getCartePuce() { 
      CartePuce cp = new CartePuce(Num, Nom); 
      setTransferHandler(new CartePuceTransferHandler()); 
         return cp; 
     }   
  public void paintComponent(Graphics g){ 
                 try { 
                         Image img = ImageIO.read(new File("carte.jpg")); 
                         g.drawImage(img, 0, 0,this); 
                       
                  
                 } catch (IOException e) { 
                         // TODO Auto-generated catch block 
                        g.drawString(this.Num, 30, 100); 
                        g.drawString(this.Nom, 20, 150); 
                             
                         
                         e.printStackTrace(); 
                 } 
                  
         }                
 }