Question : Kilo Convertor Window Class

Im trying to figure out why i keep getting an error message for this code im working with and i cant seem to figure it out

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             import javax.swing.*;
   import java.awt.event.*;
 
    public class KiloConvertorWindow extends JFrame
   {
      private JPanel panel;
      private JPanel messageLabel;
      private JLabel mileageLabel;
      private JTextField kiloTextField;
      private JTextField milesTextField;
      private JButton calcButton;
   
      private final int WINDOW_WIDTH = 370;
      private final int WINDOW_HEIGHT = 150;
   
       public KiloConvertorWindow()
      {
         setTitle("Kilometer Convertor");
         setSize( WINDOW_WIDTH, WINDOW_HEIGHT );
         setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
      
         buildPanel();
      
         add(panel);
         setVisible( true );
      }
   
       public void buildPanel()
      {
         messageLabel	=	new	JLabel( "Enter a distance in Kilometers:");
         kiloTextField	=	new	JTextField( 10 );
         milesTextField	=	new	JTextField( "The Miles are: ");
         calcButton	=	new	JButton( "Calculate");
      
         milesTextField.setEditable( false );
      
         calcButton.addActionListener( new CalcButtonListener());
      
         panel	=	new	JPanel();
      
         panel.add( messageLabel );
         panel.add( kiloTextField );
         panel.add( mileageLabel );
         panel.add( milesTextField );
         panel.add( calcButton );
      }
   
       private class CalcButtonListener implements ActionListener
      {
          public void actionPerformed( ActionEvent evt )
         {
            String input;
            double miles;
         
            input	=	kiloTextField.getText();
         
            miles	=	Double.parseDouble( input ) * .06214;
         
            milesTextField.setText( Double.toString( miles ));
         
            JOptionPane.showMessageDialog( null, input + " Kilometers is: " +
               													miles + " Miles.");
         }
      }
   }

           
         

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Answer : Kilo Convertor Window Class

You don't have a main() method (which may be intentional).
You did not define messageLabel to be of type JLabel.
You did not instantiate mileageLabel.

                       
         
           
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             import javax.swing.*;
   import java.awt.event.*;
 
    public class KiloConvertorWindow extends JFrame
   {
      private JPanel panel;
      private JLabel messageLabel;
      private JLabel mileageLabel;
      private JTextField kiloTextField;
      private JTextField milesTextField;
      private JButton calcButton;
   
      private final int WINDOW_WIDTH = 370;
      private final int WINDOW_HEIGHT = 150;
   
       public KiloConvertorWindow()
      {
         setTitle("Kilometer Convertor");
         setSize( WINDOW_WIDTH, WINDOW_HEIGHT );
         setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
      
         buildPanel();
      
         add(panel);
         setVisible( true );
      }
 
       public static void main(String[]a){new KiloConvertorWindow();}
   
       public void buildPanel()
      {
         messageLabel   =       new     JLabel( "Enter a distance in Kilometers:");
         mileageLabel   =       new     JLabel("km");
         kiloTextField  =       new     JTextField( 10 );
         milesTextField =       new     JTextField( "The Miles are: ");
         calcButton     =       new     JButton( "Calculate");
      
         milesTextField.setEditable( false );
      
         calcButton.addActionListener( new CalcButtonListener());
      
         panel  =       new     JPanel();
      
         panel.add( messageLabel );
         panel.add( kiloTextField );
         panel.add( mileageLabel );
         panel.add( milesTextField );
         panel.add( calcButton );
      }
   
       private class CalcButtonListener implements ActionListener
      {
          public void actionPerformed( ActionEvent evt )
         {
            String input;
            double miles;
         
            input       =       kiloTextField.getText();
         
            miles       =       Double.parseDouble( input ) * .06214;
         
            milesTextField.setText( Double.toString( miles ));
         
            JOptionPane.showMessageDialog( null, input + " Kilometers is: " +
                                                                                                                miles + " Miles.");
         }
      }
   }

           
         

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