定义的JLabel显示不出来？

我也是学JAVA的，刚才写代码时碰到一个问题，能否给解答一下？下面的这段代码编译正常，但是JLabel8就是显示不出来？
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.border.*;public class Register extends JFrame{
    JPanel panel1=new JPanel();
    JLabel jLabel1=new JLabel();
    JTextField nickname=new JTextField();
    JLabel jLabel2=new JLabel();
    JLabel jLabel3=new JLabel();
    JPasswordField password=new JPasswordField();
    JLabel jLabel4=new JLabel();
    JTextField email=new JTextField();
    JLabel jLabel5=new JLabel();
    JLabel jLabel6=new JLabel();
    JTextPane info=new JTextPane();
    JButton jButton1=new JButton();
    JButton jButton2=new JButton();
    JLabel jLabel7=new JLabel();
    JRadioButton boy=new JRadioButton();
    JRadioButton girl=new JRadioButton();
    ButtonGroup buttonGroup=new ButtonGroup();//设置按钮组，使其只能选其一
    JLabel jLabel8=new JLabel();
    JComboBox place=new JComboBox();
    ImageIcon[] icons=new ImageIcon[6];    public Register(){
      super();
      panel1.setLayout(null);
      this.setTitle("张朋，这是我用JAVA做的一个窗口");
      jLabel1.setText("昵称");
      jLabel1.setBounds(new Rectangle(9,45,41,18));
      nickname.setBounds(new Rectangle(50,44,128,22));
      jLabel2.setText("请填写以下内容");
      jLabel2.setBounds(new Rectangle(9,9,103,18));
      jLabel3.setText("密码");
      jLabel3.setBounds(new Rectangle(200,44,41,18));
      password.setBounds(new Rectangle(247,42,100,22));
      jLabel4.setText("电子邮件");
      jLabel4.setBounds(new Rectangle(2,102,58,18));
      email.setBounds(new Rectangle(55,96,124,22));
      jLabel5.setText("头像");
      jLabel5.setBounds(new Rectangle(193,96,51,18));
      for(int i=0;i<6;i++){
        icons[i]=new ImageIcon((i+1)+".gif");
      }
      ComboBoxModel mode=new AModel();
      JComboBox headpic=new JComboBox(mode);
      headpic.setBounds(new Rectangle(247,96,70,22));
      headpic.setRenderer(new ACellRenderer());
      headpic.setMaximumRowCount(3);
      /*ComboBoxModel model=new HeadPicCombobox(pics);
      ListCellRenderer renderer=new HeadpicCellRenderer();*/
      jLabel6.setText("个人资料");
      jLabel6.setBounds(new Rectangle(6,189,87,18));
      info.setBounds(new Rectangle(5,208,363,103));
      jButton1.setText("确定");
      jButton1.setBounds(new Rectangle(147,330,79,29));
      jButton2.setText("取消");
      jButton2.setBounds(new Rectangle(260,329,79,29));
      jLabel7.setText("性别");
      jLabel7.setBounds(new Rectangle(9,156,41,18));
      boy.setText("男");
      boy.setBounds(new Rectangle(43,152,38,26));
      buttonGroup.add(boy);
      girl.setText("女");
      girl.setBounds(new Rectangle(80,152,38,26));
      buttonGroup.add(girl);
      jLabel8.setText("来自");
      jLabel8.setBounds(new Rectangle(20,189,50,30));
      place.setBounds(new Rectangle(247,156,70,22));
      addWindowListener(new WindowAdapter(){
        public void windowClosing(WindowEvent e){
          System.exit(0);
        }
      });
      panel1.add(jLabel1);
      panel1.add(jLabel2);
      panel1.add(jLabel3);
      panel1.add(jLabel4);
      panel1.add(jLabel5);
      panel1.add(jLabel6);
      panel1.add(jLabel7);
      panel1.add(jButton1);
      panel1.add(jButton2);
      panel1.add(nickname);
      panel1.add(password);
      panel1.add(email);
      panel1.add(info);
      panel1.add(boy);
      panel1.add(girl);
      panel1.add(place);
      panel1.add(headpic);
      setLocation(100,100);
      setSize(300,500);
      setVisible(true);
      this.setContentPane(panel1);
    }
    
    public static void main(String[] args){
      Register r=new Register();
      r.show();
    }
    
    class AModel extends DefaultComboBoxModel{
       AModel(){
        for(int i=0;i<icons.length;i++){
          ItemObj obj=new ItemObj(icons[i]);
          addElement(obj);
        }
      }
  }
}class ItemObj{
    ImageIcon icon;
  
    public ItemObj(ImageIcon icon){
      this.icon=icon;
    } 
}class ACellRenderer extends JLabel implements ListCellRenderer{
    ACellRenderer(){
      setOpaque(true);
    }
    
    public Component getListCellRendererComponent(JList list,
                                                  Object value,
                                                  int index,
                                                  boolean isSelected,
                                                  boolean cellHasFocus){
      if(value!=null){
        setIcon(((ItemObj)value).icon);
      }
      if(isSelected){
        setBackground(list.getSelectionBackground());
        setForeground(list.getSelectionForeground());
      }else{
        setBackground(list.getBackground());
        setForeground(list.getForeground());
      }
      return this;
    }
}