Copy items from one list to another list box

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MultipleSelection extends JFrame
     {
     private JList colorList, copyList;
     private JButton copy;
     private String colorNames[] =
         { "Black", "Blue", "Cyan", "Dark Gray", "Gray",
         "Green", "Light Gray", "Magenta", "Orange", "Pink",
     "Red", "White", "Yellow" };
   
     public MultipleSelection()
         {
         super( "Multiple Selection Lists" );
       
         Container c = getContentPane();
         c.setLayout( new FlowLayout() );
       
         colorList = new JList( colorNames );
         colorList.setVisibleRowCount( 5 );
         colorList.setFixedCellHeight( 15 );
         colorList.setSelectionMode( ListSelectionModel.MULTIPLE_INTERVAL_SELECTION );
         c.add( new JScrollPane( colorList ) );
       
         // create copy button
         copy = new JButton( "Copy >>>" );
         copy.addActionListener( new ActionListener()
             {
             public void actionPerformed( ActionEvent e )
                 {
                 // place selected values in copyList
                 copyList.setListData( colorList.getSelectedValues() );
             }
         });
         c.add( copy );
       
         copyList = new JList( );
         copyList.setVisibleRowCount( 5 );
         copyList.setFixedCellWidth( 100 );
         copyList.setFixedCellHeight( 15 );
         copyList.setSelectionMode( ListSelectionModel.SINGLE_INTERVAL_SELECTION );
         c.add( new JScrollPane( copyList ) );
       
         setSize( 300, 120 );
         show();
     }
   
     public static void main( String args[] )
         {
         MultipleSelection app = new MultipleSelection();
       
         app.addWindowListener( new WindowAdapter()
             {
             public void windowClosing( WindowEvent e )
                 {
                 System.exit( 0 );
             }
         } );
     }
}