[RESOLVED] JAVA 6 GroupLayout

Hello,
could anyone please tell me what is wrong with this code
code compiles but throw exception at runtime.

Code:

---

import java.awt.*;
import javax.swing.*;
public class TestGroup extends JFrame{
        JTextField UserText, PasswordText ;
        JLabel UserLabel, PasswordLabel ;
        JPanel pnl ;
        public static void main( String[] args ) {
        TestGroup test = new TestGroup();
        test.start();
        }

        void start(){
                this.getContentPane().setLayout( new FlowLayout() ) ;

                UserText = new JTextField() ;
                PasswordText = new JTextField() ;
                pnl = new JPanel() ;

                GroupLayout lout = new GroupLayout( pnl ) ;
                pnl.setLayout( lout ) ;
                lout.setAutoCreateGaps( true ) ;
                lout.setAutoCreateContainerGaps( true ) ;
                GroupLayout.SequentialGroup hgroup = lout.createSequentialGroup() ;
                hgroup.addGroup( lout.createParallelGroup().addComponent(UserLabel).addComponent( PasswordLabel ) ) ;
                hgroup.addGroup( lout.createParallelGroup().addComponent( UserText).addComponent( PasswordText ) );
               
                lout.setHorizontalGroup( hgroup ) ;



                GroupLayout.SequentialGroup vgroup = lout.createSequentialGroup() ;

                vgroup.addGroup( lout.createParallelGroup().addComponent( UserLabel ).addComponent( UserText ) ) ;
                vgroup.addGroup( lout.createParallelGroup().addComponent( PasswordLabel ).addComponent( PasswordText ) );
               
                lout.setVerticalGroup( vgroup ) ;
       
                this.getContentPane().add( pnl ) ;
                this.setSize( 500, 500 ) ;
                this.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ) ;
                this.setVisible( true );
        }
}

---

Error :

Exception in thread "main" java.lang.IllegalArgumentException: Component must be
non-null
at javax.swing.GroupLayout$ComponentSpring.<init>(Unknown Source)
at javax.swing.GroupLayout$ComponentSpring.<init>(Unknown Source)
at javax.swing.GroupLayout$Group.addComponent(Unknown Source)
at javax.swing.GroupLayout$ParallelGroup.addComponent(Unknown Source)
at javax.swing.GroupLayout$ParallelGroup.addComponent(Unknown Source)
at javax.swing.GroupLayout$Group.addComponent(Unknown Source)
at javax.swing.GroupLayout$ParallelGroup.addComponent(Unknown Source)
at TestGroup.start(TestGroup.java:24)
at TestGroup.main(TestGroup.java:9)

You forgot to initialize the components PasswordLabel and UserLabel before using them

oooooooooops silly mistake

thank you very much, my focus was on the grouplayout thats why i could not see that. it was running well if i comment that grouplayout portion so i thought i have done something wrong there only.

thanks again.